Authors:G. Zsivanovits, Ts. Grancharova, I. Dimitrova-Dyulgerova, D. Ivanova, S. Kostadinova and M. Marudova
The research presents the effect of novel edible coatings based on low molecular weight chitosan on some properties of fresh-cut melon fruits – weight loss, total soluble solids, total acidity, mechanical strength and bacteria growth. Three different compositions were used as coatings – pure chitosan, chitosan and Ca lactate and alginate/chitosan multilayers. It was shown that the additional alginate layer substantially improves the protective properties of pure chitosan coating, resulting in preservation of cell structure. Negligible negative effect on the antibacterial activity of pure chitosan is demonstrated.
Authors:Balázs Lemmer, Szabolcs Kertész, Gábor Keszthelyi-Szabó, Kerime Özel and Cecilia Hodúr
Membrane separation processes are currently proven technologies in many areas. The main limitation of these processes is the accumulation of matter at the membrane surface which leads to two phenomena: concentration polarization and membrane fouling. According to the publications of numerous authors permeate flux could be increased by sonication. Our work focuses on separation of real broth by sonicated ultrafiltration. The broth was originated from hydrolysis of grounded corn-cob by xylanase enzyme. The filtration was carried out in a laboratory batch stirred cell with a sonication rod sonicator. In our work the effect of the stirring, the intensity of sonication and the membrane-transducer distance was studied on the efficiency of the ultrafiltration and on the quality of separated enzymes. Results reveal that xylanase enzyme can be effectively separated from real fermentation broth by ultrafiltration and enzymes keep their activity after the process. Enzyme activity tests show that low energy sonication is not harmful to the enzyme.
Authors:Monika Božiková, Peter Hlaváč, Vlasta Vozárová, Zuzana Hlaváčová, Ľubomír Kubík, Peter Kotoulek and Ján Brindza
Knowledge of bee products’ physical properties has a decisive importance for the monitoring of their quality. Thermophysical parameters are very important properties. Thermal conductivity and thermal diffusivity of selected bee products (honey, bee pollen and perga) were measured by two different methods. For identification of thermal conductivity and thermal diffusivity transient methods were used: Hot Wire (HW) and Dynamic Plane Source (DPS) method with an instrument Isomet 2104. The principle of measuring process is based on the analysis of timetemperature relation. In the first series of measurements thermal conductivity and diffusivity at constant laboratory temperature of 20 °C were measured. The second series was focused on identification of the changes in the thermophysical parameters during temperature stabilisation in the temperature range of 5–25 °C. For samples with constant temperature standard deviations and probable errors in % were calculated. For relations of thermal parameters to temperature graphical dependencies were obtained. Two different thermophysical methods were used for improvement of data reliability and data statistics.
The study focused on the efficacy of ultrasonic method for identifying vegetable oils and their mixtures in the formulation of frying oil and its ability in authentication of virgin olive oil. The ultrasonic propagation properties (velocity and Time of Flight (TOF)) were used to classify oil samples and their mixtures at 1 MHz. The results revealed the ability to classify oil types in terms of their level of un-saturation, besides it is to identify oil mixtures. Each oil sample could be grouped into different clusters using ultrasonic parameters. Hence, ultrasonic could be used to discriminate the vegetable oil types and their mixtures effectively as a rapid and continuous method in the industrial in-line quality control system of vegetable oils and their mixtures.
Authors:Péter Bor, József Csanádi, Gábor Veréb, Sándor Beszédes, Zita Šereš, Zsuzsanna László, Cecilia Hodúr and Szabolcs Kertész
To meet the requirements defined by environmental protection regulations effective wastewater treatment is required to process effluents before discharging them into sewers or living waters. While membrane separation offers a quite advantageous method to reduce the organic load of wastewaters, membrane fouling is still limiting its application in wastewater treatment.
In this study, the possibility of membrane fouling reduction by increased shear rates on the surface of the membrane was investigated. 7 and 10 kDa MWCO ultrafiltration and 240 Da nanofiltration membranes were studied, with the use of a laboratory mode Vibratory Shear Enhanced Processing. This work mostly focused on studying the effects of module vibration and recirculation feed flow rate on permeate flux, specific energy demand and membrane rejections. Using the same operation parameters, vibration and non-vibration mode experiments were carried out with high and low recirculation flow rate to have a deeper understanding of the shear rate effects. It can be concluded that higher shear rate had a positive effect on the process: increased shear rate resulted in higher flux, higher overall rejection values, as well as a significantly decreased specific energy demand. By calculating and comparing the shear rates in experiments with different operating parameters, both vibration and nonvibration mode, both low and high recirculation flow rate, we have reached the conclusion that vibration causes a significantly higher shear rate increase than setting the recirculation flow rate high.
Authors:M. Jolánkai, Á. Tarnawa, H. F. Nyárai, Z. Szentpétery and M. K. Kassai
Long-term trials are established in order to explore and observe plant and soil interrelationships in situ. Long-term trials can be described as live instruments providing ceteris paribus conditions in temporal sequences.
This review provides an introduction to major long-term trials in Hungary and in other parts of the world. It gives a brief summary of the origins of plant nutritional research, beginning with some data from Homer and the willow tree experiment of van Helmont, as well as the discovery of physiological processes by von Liebig, Lawes and Boussingault. The most profound long-term trials, like the Orto Botanico in Padova, the Linné Garden in Uppsala and the Broadbalk in Rothamsted are presented in the paper.
The agronomic, educational and scientific benefits of the major Hungarian long-term trials are also discussed, from Westsik (1929) to Martonvásár and the National Plant Nutrition Trials (OMTK) set up in 1963. There is a list of experimental sites giving information on the most important recent long-term trial locations and their activities.
Authors:R. K. Gangwar, M. Makádi, M. Fuchs, Á. Csorba, E. Michéli, I. Demeter and T. Szegi
Soil samples were collected from salt-affected soils (Solonetz) under different land uses, namely arable (SnA) and pasture (SnP), to investigate the effects of land use on microbiological [basal soil respiration (BSR), microbial biomass carbon (MBC), dehydrogenase activity (DHA) and phosphatase activity] and chemical properties [organic carbon (OC), humic ratio (E4/E6), pH, electrical conductivity (EC), ammonium nitrogen (NH4-N), nitrate nitrogen (NO3-N), available forms of phosphorus (P2O5), potassium (K2O), calcium (Ca2+), magnesium (Mg2+), sodium (Na+)] and on the moisture content.
The results showed that the two sites, SnA and SnP, were statistically different from each other for all the microbiological and chemical parameters investigated except Na+ and moisture content. Higher values of MBC (575.67 μg g-1), BSR (9.71 μg CO2 g-1 soil h-1), DHA (332.76 μg formazan g-1 day-1) and phosphatase activity (0.161 μmol PNP g-1 hr-1) were observed for the SnP soil. Great heterogeneity was found in SnP in terms of microbiological properties, whereas the SnA plots showed more homogeneous microbiological activity due to ploughing. 75.34% of variance was explained by principal component one (PC1), which significantly separated SnA and SnP, especially on the basis of soil MBC and P2O5. Moreover, it was concluded that the pasture land (SnP) was microbiologically more active than arable land (SnA) among the Hungarian salt-affected soils investigated.
Authors:Peiwu Geng, Jing Zhang, Bingbao Chen, Qianqian Wang, Shuanghu Wang and Congcong Wen
Dauricine is the major bioactive component isolated from the roots of Menispermum dauricum D.C., a bisbenzylisoquinoline alkaloid derivative, and has shown multiple pharmacological properties. In this work, a sensitive and selective ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed for determination of dauricine in rat plasma and its application to pharmacokinetic study of dauricine after intravenous and oral administration in rats. After addition of daurisoline as an internal standard (IS), protein precipitation by acetonitrile was used to prepare samples. Chromatographic separation was achieved on a UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) with 0.1% formic acid and acetonitrile as the mobile phase with gradient elution. An electrospray ionization source was applied and operated in positive ion mode; multiple reactions monitoring (MRM) mode was used for quantification. Calibration plots were linear throughout the range 2–600 ng mL−1 for dauricine in rat plasma. Relative standard deviation (RSD) of intra-day and inter-day precision was less than 13%. The accuracy of the method was between 95.8% and 105.9%. Matrix effect of dauricine in rat plasma ranged from 88.0% to 90.3%. Mean recoveries of dauricine in rat plasma ranged from 91.5% to 95.1%. The method was successfully applied to pharmacokinetic study of dauricine after intravenous and oral administration in rats. The bioavailability of dauricine was found to be 55.4% for the first time.
Authors:Yunfang Zhou, Bingbao Chen, Junyan Chen, Yanwen Dong, Shuanghu Wang, Congcong Wen, Xianqin Wang and Xiaomin Yu
In this work, a sensitive and selective ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed and fully validated for determination of jaceosidin in rat plasma. Avicularin was used as the internal standard (IS), and protein precipitation by acetonitrile was used to prepare samples. Chromatographic separation was achieved on a UPLC BEH C18 column (2.1 mm × 100 mm, 1.7 μm) with 0.1% formic acid and acetonitrile as the mobile phase with gradient elution. An electrospray ionization (ESI) source was applied and operated in positive ion mode; multiple reaction monitoring (MRM) mode was used for quantification. Calibration plots were linear throughout the range 2–500 ng mL−1 for jaceosidin in rat plasma. Relative standard deviation (RSD) of intra-day and inter-day precision was less than 12%. The accuracy of the method was between 88.7% and 109.7%. Mean recoveries of jaceosidin in rat plasma ranged from 65.4% to 77.9%. The developed UPLC–MS/MS method was successfully applied to pharmacokinetic study of jaceosidin after intravenous administration of 2 mg kg−1 in rats. We could find that the jaceosidin rapidly eliminated, the t1/2 was 0.7 ± 0.3 h, and clearance (CL) was 22.4 ± 3.0 L h−1 kg−1.
Authors:Maosheng Ran, Ping Xie, Xiaohai Tang, Guangfu Zeng and Jinliang Yang
A newly proposed method for detecting content of adriamycin in pectin–adriamycin conjugate has been developed and evaluated. The content of adriamycin was detected by selective degradation of adramycin to adriamycinone. It was realized by a two-phase reaction system (water–chloroform reaction system), in which adriamycin was quantitatively converted to adriamycinone. Therefore, the latter can be used to calculate the precise content of adramycin in the polymer drug. To develop the method, the catalyst for degradation, the extraction solvent for adriamycinone, the temperature and time of degradation, and the ratio of pectin–adriamycin conjugate were investigated. The optimal reaction condition was as follows: 30 mg of pectin–adriamycin conjugate dissolved in 25 mL of water was added to a mixture of 25 mL of hydrochloric acid (1.5 mol/L) and 50 mL of chloroform; the mixture was heated to 40 °C to react for 1.5 h; after that, the mixture was extracted with chloroform for three times, and then the organic layer was combined and, subsequently, evaporated to remove solvent. Under this condition, adriamycinone generation rate reached 99.87%. The quantitative method was evaluated for linearity, the limit of detection (LOD) and limit of quantitation (LOQ), recovery, accuracy, robustness, and precision. The recoveries were between 99.47% and 101.07% with relative standard deviation <1.23%. The LOD and LOQ were 0.06 and 0.17 μg/mL, respectively. Compared to the traditional ultraviolet (UV) detection, this method is considered to be more precise for detecting content of adriamycin in its polymer conjugate.
A novel multi-walled carbon nanotubes (MWCNTs) dispersive solid phase extraction (d-SPE) method which combined with gas chromatography (GC) coupled with electron capture detector (ECD) was developed for the determination of five pyrethroid pesticides in liquid milk for the first time. The effect of d-SPE conditions on the kinds of sorbent, MWCNTs and magnesium sulfate anhydro mass ratio, and extraction condition were researched, and then, the suitable method was found. Under the optimal conditions, the linear range was from 20 to 500 μg kg−1. The recoveries were from 81.8% to 112.1%, with the corresponding relative standard deviations (RSDs) less than 6%, correlation coefficients from 0.9978 to 0.9990, and limits of detection and quantification from 2.62 to 4.86 μg kg−1 and 8.73 to 16.2 μg kg−1. The proposed method is simple, fast, safe, and has high recovery and sensitivity applicable to analyze pyrethroid pesticides in liquid milk sample.
Authors:Marcin Gackowski, Marcin Koba, Katarzyna Mądra-Gackowska, Robert Pluskota, Emilia Główczewska-Siedlecka, Zygmunt Siedlecki and Michał P. Marszałł
This study describes the development and validation of some analytical methods as high-performance thin-layer chromatography (HPTLC), ultraviolet (UV)–densitometry, UV–high-performance liquid chromatography (HPLC), and derivative spectrophotometry elaborated for the estimation of lormetazepam in pharmaceutical formulations. HPTLC method was performed using silica plates, a mobile phase composed of acetonitrile‒water (6:4, v/v), and a densitometric detection at 241 nm. UV‒derivative spectrophotometry method was applied, and at first, the direct spectrum was recorded, then first-, second-, and third-derivative spectra were obtained and measured by peak-zero (P-0) or peak-peak (P-P) techniques. Moreover, HPLC method was performed using a Gemini C18 column and isocratic elution mode with a mobile phase composed of acetonitrile–water (65:35, v/v) and delivered at a flow rate of 0.5 mL min−1. In the case of HPTLC analysis, the quantification was achieved with acceptable precision (relative standard deviation [RSD] = 5.39%) and recovery of 98.53%, using a nonlinear calibration curve. For the UV‒derivative spectrophotometry method, all derivatives and wavelengths studied proved good linearity, precision (RSD = 2.30–6.13), and recovery (91.17–98.70%). On the other hand, the elaborated HPLC method provided good results of precision (RSD = 2.16%) and recovery of 97.60% in the concentration range of 1.95–62.5 μg mL−1 using linear regression analysis. It was concluded that the best results were found for HPLC method; however, all the developed methods can be considered comparable and successfully applied to the routine quality control of this drug in dosage form.
The contents of the four components in different growth stages of Artemisia rupestris L. was determined by thin-layer chromatographic scanning. Chloroform, methanol, formic acid, and water with the proportion of 6.35:0.63:0.17:0.07 were used as the developing solvent. The temperature was 28–32°C. The humidity was less than 30%. The scanning wavelengths were 250 nm and 352 nm. The linearity ranges of rupestonic acid, vitexicarpin, apigenin, and luteolin were 0.128–0.725, 0.0706–0.400, 0.0255–0.145, and 0.0172–0.0976 μg, respectively. The components had the corresponding correlation coefficients of 0.9909, 0.9908, 0.9971, and 0.9934, which showed a good linear relationship. Precision analyses showed a relative standard deviation of <5.0%. Stability studies showed that rupestonic acid, vitexicarpin, apigenin, and luteolin can be stable for at least 30 min at room temperature. Their average recovery percentages were 99.9%, 103.6%, 98.07%, and 99.9%, respectively. The contents of the four components in the different growth stages of A. rupestris L. were studied. The obvious changes of the four components could be used as the control for the quality of A. rupestris L. and the determination of the time of harvest.
Authors:Vladimir Dobričić, Aleksa Stanišić, Sote Vladimirov and Olivera Čudina
Octanol–water partition coefficients (log Po/w) of fifteen previously synthesized 17β-carboxamide glucocorticoid derivatives and prednisolone were determined using shake-flask method. The retention behavior of selected compounds was tested in five reversed-phased thin-layer chromatography (RP-TLC) systems, consisting of water and organic solvent (acetonitrile, acetone, ethanol 96%, methanol, or tetrahydrofuran), and chromatography parameters (RM0, S, and C0) were calculated. Simple linear regression (SLR) analysis was performed, and the correlation between log Po/w and chromatography parameters was tested. The most appropriate RP-TLC system for log Po/w prediction was that consisting of water and ethanol 96% as the mobile phase. Statisitical evaluation of the quality of models created using this system proved their reliability for log Po/w prediction of new 17β-carboxamide glucocorticoid derivatives, and the model with the most favorable statistical parameters was underlined.
Authors:Bárbara Borges, Armindo Melo, Isabel M.P.L.V.O. Ferreira and Catarina Mansilha
A new method for simultaneous extraction and quantification of 6 nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) and 16 parent polycyclic aromatic hydrocarbons (PAHs) in water matrices was optimized and validated.
The extraction procedure was based on dispersive liquid-liquid microextraction technique, followed by gas chromatography-mass detection. The optimum conditions of extraction (volume of the extraction solvent, dispersive solvents and amount of salt) were selected using central composite design. The best results were found by using 200 μL of acetonitrile as dispersive solvent, 60 μL of chloroform as extraction solvent, and 10% (w/v) NaCl. Excellent linearity was observed in the range of 10–150 ng L−1 with correlation coefficients (r2) ranging between 0.9996 and 0.9999 for nitro-PAHs and in the range of 5–150 ng L−1 with r2 ranging from 0.9998 to 1.000 for PAHs. The limits of detection for the nitro-PAHs studied ranged from 0.82 to 3.37 ng L−1, whereas for PAHs ranged from 0.62 to 3.48 ng L−1. The intra- and inter-day precisions for nitro-PAHs were in the range of 0.45 to 19.54% and 0.43 to 19.62%, respectively, and for PAHs ranged between 0.45 to 17.42% and 0.38 to 18.97%, respectively. The proposed method was successfully applied in analyses of groundwater, sea, rain water and river water, being appropriate for routine analyses.
This article enfolds a rapid and sensitive high-performance thin-layer chromatographic (HPTLC) method for the estimation of four triterpenoids, namely, betulin (BU), betulinic acid (BA), lupeol (LU), and oleanolic acid (OA), from the bark, roots, and leaves of Betula utilis D. Don, an endangered Himalayan tree. All the four phytoconstituents have high therapeutic value. Separation was performed on thin-layer chromatography (TLC) aluminum plates precoated with silica 60 F254 (20 × 20 cm) followed by detection of betulin, lupeol, and oleanolic acid carried out by derivatizing the plate with ceric ammonium sulfate followed by heating at 110°C for 5 min. For betulinic acid, the plate was dried and visualized after spraying with Liebermann‒Burchard reagent. CAMAG TLC Scanner 4 equipped with winCATS software was used for densitometric scanning at 500–550 nm. The proposed technique was further validated in terms of linearity, precision, accuracy, and sensitivity as per the International Conference on Harmonisation (ICH) guidelines. A good linear relationship was obtained for the calibration plots with r2 = 0.9994, 0.9995, 0.9969, and 0.9998 for betulin, lupeol, oleanolic acid, and betulinic acid, respectively. Accuracy of the method was checked by recovery study conducted at three different levels with the average recovery between 98.9% and 99.3% for all the four markers.
The extraction of crude drugs by using different solvents provides polarity-based fractions containing specific types of secondary metabolites. Averrhoa carambola L. fruits were extracted and fractionated, and petroleum ether extract was processed by fatty acid methyl ester (FAME) technique for characterization by gas chromatography‒mass spectrometry (GC‒MS) analysis. The remaining part was extracted with methanol for high-performance thin-layer chromatography (HPTLC) analysis, for simultaneous quantitative determination of gallic acid, protocatechuic acid, and quercetin in methanolic fractions. Petroleum ether and methanol fractions were found to be the best for the highest possible recovery of target analytes. The chromatographic elutions of FAME compounds generated from ether extract were evaluated by GC‒MS profiling. Ten fatty acid compounds were separated with the highest quantity of oleic acid methyl ester (42.88%). On other hand, polar fraction was processed by HPTLC profiling. For achieving good separation, a mobile phase of toluene‒ethyl acetate‒formic acid (5:4:1, v/v) was used. The densitometric determination was carried out at 310 nm in reflection–absorption mode. The calibration curves were linear in the range of 100–600 ng per spot for gallic acid, protocatechuic acid, and quercetin. During the analysis, the dried raw material from A. carambola L. fruits showed the presence of gallic acid (0.96%), protocatechuic acid (0.05%), and quercetin (0.40%). The proposed method is simple, precise, specific, and accurate. The statistical analysis of the data obtained proves that the method is reproducible and selective and can be used for the routine analysis of the reported phenolic compounds in crude drug and extracts. The results indicated that the methanolic extracts of the plant contained a considerable amount of bioactive compounds. The presence of phytochemicals especially phenolics and flavonoids explains its use in various diseases. It may be concluded that the results obtained from the quantitative evaluation of quercetin by HPTLC fingerprinting could be useful in its authentication, the quality control of the drug, and in ensuring therapeutic efficacy.
Authors:Ahmed I. Foudah, Prawez Alam and Maged S. Abdel-Kader
Novel, simple, and sensitive high-performance thin-layer chromatography (HPTLC) with fluorescence detection method has been successfully established and validated for the simultaneous determination of vulgarin and epivulgarin in different collections of Artemisia judaica. HPTLC method was carried out using glass plates coated with silica gel 60 F254 using petroleum ether‒acetone (7:3, v/v) as the mobile phase. After development, the plates were scanned and quantified densitometrically at 224 nm for both vulgarin and epivulgarin. The two compounds’ peaks from A. judaica were identified by comparing their single spot at RF = 0.30 ± 0.02 and RF = 0.36 ± 0.01, respectively, with those of vulgarin and epivulgarin. Linear regression analysis revealed a good linear relationship between peak area and amount of vulgarin and epivulgarin in the range of 100–700 ng band−1 for both compounds. The method was validated, in accordance with the International Conference on Harmonization (ICH) guidelines, for precision, accuracy, and robustness. The proposed method will be useful to measure the therapeutic dose of vulgarin and epivulgarin in A. judaica extracts.
Authors:Cornelia Locher, Edith Tang, Jonas Neumann and Tomislav Sostaric
This article presents the findings of an in-depth study on high-performance thin-layer chromatographic (HPTLC) profiling of Jarrah (Eucalyptus marginata) and Manuka (Leptospermum spp.) honeys following a simple one-step solvent extraction process. The study demonstrates that different HPTLC fingerprints are obtained from honeys from varying floral sources and that honeys of the same floral origin present a consistent reproducible HPTLC profile. In addition, the linearity and reproducibility of this technique as well as its ability to detect (accidental or deliberate) contaminations with honeys of different floral sources are demonstrated. The study thus illustrates the usefulness of HPTLC profiling as a potential quality control tool that might complement other analytical techniques used in the authentication of monofloral honeys.
Authors:Vania Maslarska, Boyka Tsvetkova, Lily Peikova and Stanislav Bozhanov
A high-performance liquid chromatography (HPLC) method with ultraviolet (UV) detection for simultaneous determination of metronidazole, methylparaben, and propylparaben in vaginal gel formulation was described. The chromatography was carried out on a C18 (250 mm × 4.6 mm, 5 μm) column with acetonitrile and 0.3% phosphoric acid solution (20:80 v/v) modified by 0.1% triethylamine as mobile phase, at a flow rate of 1.0 mL min−1, with detection at 260 nm. Under these chromatographic conditions, the obtained retention times were approximately 3.43 min for metronidazole, 5.17 min for propylparaben, and 15.12 min for methylparaben.
Analytical parameters specificity, linearity, accuracy, and precision were determined by validation procedure and found to be satisfactory. Overall, the proposed method was found to be simple, precise, and accurate for quality control of metronidazole in the presence of preservatives in gel formulation.
Authors:Y. C. Xiao, L. T. Liu, J. J. Bian, C. Q. Yan, L. Ye, M. X. Zhao, Q. S. Huang, W. Wang, K. Liang, Z. F. Shi and X. Ke
Shuganjieyu (SGJY) capsule is a classical formula widely used in Chinese clinical application. In this paper, an ultra-performance liquid chromatography coupled with electrospray ionization and ion trap mass spectrometry has been established to separate and identify the chemical constituents of SGJY and the multiple constituents of SGJY in rats. The chromatographic separation was performed on a C18 RRHD column (150 × 2.1 mm, 1.8 μm), while 0.1% formic acid–water and 0.1% formic acid–acetonitrile was used as mobile phase. Mass spectral data were acquired in both positive and negative modes. On the basis of the characteristic retention time (Rt) and mass spectral data with those of reference standards and relevant references, 73 constituents from the SGJY and 15 ingredients including 10 original constituents and 5 metabolites from the rat plasma after oral administration of SGJY were identified or tentatively characterized. This study provided helpful chemical information for further pharmacology and active mechanism research on SGJY.
Authors:László Simon, Béla Szabó, György Vincze, Miklós Szabó and József Koncz
Willow was cultivated as an energy crop in a field experiment. The brown forest soil was treated with an inorganic fertilizer (ammonium nitrate−AN: 100 kg ha-1) or with various organic or mineral soil amendments (municipal biocompost–MBC: 20 t ha−1; municipal sewage sludge compost–MSSC: 15 t ha−1; rhyolite tuff–RT: 30 t ha−1; willow ash−WA: 600 kg ha−1), or their combinations (AN+MBC; AN+RT; AN+WA, MSSC+WA) in four replications. Nineteen months after the soil treatments the macroelement-rich amendments (MBC, MSSC) enhanced the harvested fresh shoot yield most significantly (up to 41% as compared to the untreated control), and also the shoot diameter and shoot height of the willow plants. Most of the treatments enhanced the uptake of N (9.8-23.5%) and K in willow leaves, but the concentrations of P, Mg, Ca, Fe and Zn in the leaves were reduced. The toxic element (As, Cd, Pb) accumulation of willow shoots was negligible.
In a 4-year field experiment the effects of the mineral fertilizers AN and AN+calcium-magnesium carbonate (CMC) were studied on the mineral nutrition of the leaves and wood yield of black locust trees cultivated as an energy crop. The brown forest soil was treated with 300 kg ha−1 annual doses of these fertilizers as top-dressing in June 2009, May 2010 and May 2011. Both fertilizers caused a three to four times increase in the nitrate content of the upper soil soon after their application in June. By the end of the vegetation period (in December) the nitrate concentration in the soil was similar to that in the control plots. The nitrogen content of the leaf stalks (petioles) and leaves, however, was only slightly higher in the treated plots. As a trend, fertilization increased the phosphorus and reduced the calcium uptake in the leaf stalks and leaves, while the magnesium content was not influenced. In March 2012, when the whole trees were harvested, 22% or 28% higher aboveground fresh shoot weight was detected in the AN or AN+CMC treatments than in the control.
Authors:Anita Takács, Katalin Kovács, Gábor Halász, Zoltán Győri, Ilona Fekete, György Heltai and Márk Horváth
The estimation of environmental risk caused by pollution with potentially toxic elements (PTE) is usually carried out using the (3+1) step sequential extraction procedure suggested in 1993 by the Community Bureau of Reference (BCR). In the 1st step the water-soluble, exchangeable and carbonate-bound element content is extracted with acetic acid. In 2002 a fractionation procedure based on the application of supercritical CO2, subcritical H2O and of a mixture of subcritical H2O/CO2 was proposed, which allowed the water-soluble and carbonatebound element contents to be extracted separately from sediment or soil samples weighed into the preparative column of a supercritical fluid extractor and diluted with quartz sand in a mass ratio of 1:20. The aim of the present study was to develop a new reduced-size column construction with which this dilution rate could be decreased to 1:2. A kinetic study was performed to determine the extraction time necessary for samples with different carbonate contents and the extracted element contents were compared to the results of the BCR sequential procedure on the same samples. It was established that fractionation using the reduced-size column may be a rapid way to obtain more reliable information on the easily mobilizable (watersoluble and carbonate-bound) PTE content of soils and sediments than was previously available to supplement BCR fractionation.
Authors:János Kátai, Thomas Döring, Magdolna Tállai, Andrea Balla-Kovács, István Henzsel, Marianna Makádi, Zsolt Sándor and Imre Vágó
The size of the arable land is constantly decreasing all over the world due to severe anthropogenic disorders. Plant production therefore has to be adapted to changing environmental conditions along with the proper selection of crop varieties and the application of sustainable environmental technologies which also consider economic aspects. The investigations were carried out in the Westsik long-term fertilization experiment near Nyíregyháza, East Hungary, which was set up in 1929 (89 years ago). Alternative forms of nutrient supplies (A) (green manure, straw with and without fermentation, organic fertilizer with and without inorganic fertilizer supplements) were used in different crop rotations. The test plant was potato (Solanum tuberosum L.) and the soil type sand with a low humus content (Arenosols). A further long-term experiment is located on calcareous chernozem soil (Chernozems) in Debrecen (set up in 1983, 35 years ago). In one part of this experiment, organic farming (OF) has been carried out with a pea, winter wheat and maize crop rotation for over 15 years with no inorganic fertilization. In another block in this experiment, changes in soil properties as a result of the medium and high doses of fertilizers applied in intensive farming (I) were evaluated with a maize (Zea mays L.) monoculture as the test plant.
The results obtained with alternative nutrient supplies (green manure, fermented and unfermented straw, farmyard manure, fertilization) proved that the soil organic carbon content increased to varying degrees in humus-poor, acidic sand soil. The organic matter content of the soils increased in response to the treatments, contributing to a significant enhancement in soil microbial parameters (MBC, saccharase, dehydrogenase and phosphatase enzyme activities).
The carbon dioxide production and saccharase enzyme activity in organic plots (OF) were significantly lower than in intensively farmed (I) soils. At the same time, in the case of organic farming (OF) the microbial biomass carbon, phosphatase and dehydrogenase activity were significantly higher in OF plots than in I plots. Compared to the control soil, MBC was 7-8 times higher in organic plots and 1.3-3.8 times higher in intensive plots.
Organic farming on chernozem soil generally resulted in higher microbial activity (MBC, phosphatase, saccharase and dehydrogenase enzyme activity) than in either intensively farmed chernozem or in the case of alternative farming (A) on sandy soil.
Authors:Perwez Alam, Tawfeq A. Alhowiriny, Nasir A. Siddiqui, Saleh I. Alqasoumi, Omer A. Basudan, Azmat Ali Khan, Abdullah T. Alhowiriny and Nawazish Alam
Extensive research on Ficus species has shown their excellent cytotoxic potential which motivated the authors for further evaluation of its other species. In this article, the β-sitosterol content in the chloroform extract of the leaves of five Ficus species (Ficus carica [FCCE], Ficus nitida [FNCE], Ficus ingens [FICE], Ficus palmata [FPCE], and Ficus vasta [FVCE]) was estimated by a validated high-performance thin-layer chromatography (HPTLC) method along with cytotoxic activity. The chromatography was performed on glass-backed silica gel 60 F254 HPTLC plates with hexane and ethyl acetate (8:2, v/v) as the mobile phase. The developed plate was derivatized with p-anisaldehyde reagent, scanned, and quantified at λ = 550 nm. It furnished a compact and intense peak of β-sitosterol at RF = 0.17 ± 0.001. The contents of β-sitosterol (μg mg−1 of the dried weight of the extract) in the selected Ficus species were found as: FCCE (1.047 μg mg−1) > FVCE (0.771 μg mg−1) > FNCE (0.372 μg mg−1) > FPCE (0.309 μg mg−1), while it was absent in F. ingens. Methylthiazol tetrazolium (MTT) assay was used to compare the cytotoxic potential of all Ficus species against HepG2 (liver), HEK-293 (kidney), MCF-7 (breast), and MDA-MB 231 (breast) cell lines. The FCCE exhibited good cytotoxic property against HepG2, HEK-293, and MDA-MB-231 cells (IC50: 32.5, 41.4, and 47.3 μg mL−1, respectively), while FICE showed against HepG2 and MDA-MB-231 cells (IC50: 31.4 and 41.2 μg mL−1, respectively). The remaining Ficus extracts were found to be very less effective or insignificant. The cytotoxic property of FCCE is also supported by the HPTLC estimation of β-sitosterol which is reported to exhibit anticancer properties by interfering with multiple cell signaling pathways, including cell cycle, apoptosis, and proliferation. Our data suggest that the developed HPTLC method can be further employed in the analysis of marketed herbal formulations, and the active Ficus species can be further subjected to isolation of cytotoxic phytoconstituents.
Authors:Huijuan Zou, Guanghao Guo, Minglong Wang, Jianguo Cao and Guozheng Huang
By application of preparative high-speed counter-current chromatography (HSCCC) to the crude quinolone alkaloids (1.1 g) from the fruit of Tetradium ruticarpum, 1-methyl-2((6Z,9Z)-pentadecadienyl)-4(1H)-quinolone (1, 8.4 mg), dihydroevocarpine (2, 27.0 mg), and 1-methyl-2-pentadecyl-4(1H)-quinolone (3, 18.8 mg) were isolated in one step with sufficient purity using the solvent system composed of hexane–ethyl acetate–methanol–water (Hex–EtOAc–MeOH–H2O, 5:2:5:3). Further purification of the subfraction was performed by amending the solvent composition and achieved another three quinolone alkaloids, i.e., 1-methyl-2-undecylquinolin-4(1H)-one (4, 13.7 mg), (Z)-1-methyl-2-(tridec-5-en-1-yl) quinolin-4(1H)-one (5, 14.0 mg) from subfraction FR3-A3-85 using Hex–EtOAc–MeOH–H2O (5:3.5:8.75:8.25), and 1-methyl-2-nonylquinolin-4(1H)-one (6, 15.1 mg) from subfraction FR3-A3-36 using Hex–EtOAc–MeOH–H2O (5:3.8:5:4.8). The relationship between the structure of the six alkaloids and their affinities for bovine serum albumin (BSA) was investigated using fluorescence titration analysis. The length and the presence of double bond of the side chain affected their binding process with BSA. The binding behavior might influence their other biological activities.
Authors:László Simon, Marianna Makádi, György Vincze, Zsuzsanna Uri, Katalin Irinyiné Oláh, László Zsombik, Szabolcs Vígh and Béla Szabó
A small-plot long-term field fertilization experiment was set up in 2011 with willow (Salix triandra x Salix viminalis ’Inger’) grown as an energy crop in Nyíregyháza, Hungary. The brown forest soil was treated three times (in June 2011, May 2013, May 2016) with municipal biocompost (MBC), municipal sewage sludge compost (MSSC) or willow ash (WA), and twice (June 2011, May 2013) with rhyolite tuff (RT). In late May – early June 2016 urea (U) and sulphuric urea (SU) fertilizers were also applied to the soil as top-dressing (TD). These fertilizers and amendments were also applied to the soil in 2016 in the combinations; MBC+SU, RT+SU, WA+SU and MSSC+WA. All the treatments were repeated four times. In July 2016 the highest nitrogen concentrations in willow leaves were measured in the U (3.47 m/m%) and SU (3.01 m/m%) treatments, and these values were significantly higher than the control (2.46 m/m%). An excess of nitrogen considerably reduced the Zn uptake of the leaves, with values of 39.5 μg g-1 in the U treatment, 53.4 μg g-1 in the SU treatment, and 63.5 μg g-1 in the control. All other amendments or TDs, except for WA, enhanced the specific potassium concentrations in willow leaves compared to the control. No significant quantities of toxic elements (As, Ba, Cd, Pb) were transported from soil amendments or TDs to the willow leaves. In July 2016 the most intensive leaf chlorophyll fluorescence was observed in the MSSC and MSSC+WA treatments.
Authors:Nóra Péterfalvi, Boglárka Keller and Marianna Magyar
The emission of particulate matter from agricultural sources is a worldwide environmental issue due to health concerns.
The main factors influencing PM10 emission from crop production are the origin of particles, the physical and chemical properties of soils, meteorological conditions, and the mechanical impacts of farm operations. Several studies have been made to determine PM10 emission factors for tillage operations, but these emission factors varied depending on soil properties, especially soil texture and water content, and environmental conditions (e.g. relative humidity, and variability in wind speed and direction). This is why the use of a single emission factor for a given tillage operation is inadequate.
To estimate the yearly amount of PM10 emitted from agricultural soils and crop production, emissions originating from different sources at different temporal division must be summarized. Because 56 % of the total territory of Hungary is cropland, relatively high PM10 emission occurs from crop production and agricultural soils. If this is to be reduced, research should focus on the identification of soil and environmental properties related to PM10 emission on characteristic Hungarian soils.
Authors:G. Gelybó, E. Tóth, C. Farkas, Á. Horel, I. Kása and Z. Bakacsi
Climate change is expected to have a vigorous impact on soils and ecosystems due to elevated temperature and changes in precipitation (amount and frequency), thereby altering biogeochemical and hydrological cycles. Several phenomena associated with climate change and anthropogenic activity affect soils indirectly via ecosystem functioning (such as higher atmospheric CO2 concentration and N deposition). Continuous interactions between climate and soils determine the transformation and transport processes. Long-term gradual changes in abiotic environmental factors alter naturally occurring soil forming processes by modifying the soil water regime, mineral composition evolution, and the rate of organic matter formation and degradation. The resulting physical and chemical soil properties play a fundamental role in the productivity and environmental quality of cultivated land, so it is crucial to evaluate the potential outcomes of climate change and soil interactions. This paper attempts to review the underlying long-term processes influenced by different aspects of climate change. When considering major soil forming factors (climate, parent material, living organisms, topography), especially climate, we put special attention to soil physical properties (soil structure and texture, and consequential changes in soil hydrothermal regime), soil chemical properties (e.g. cation exchange capacity, soil organic matter content as influenced by changes in environmental conditions) and soil degradation as a result of longterm soil physicochemical transformations. The temperate region, specifically the Carpathian Basin as a heterogeneous territory consisting of different climatic and soil zones from continental to mountainous, is used as an example to present potential changes and to assess the effect of climate change on soils. The altered physicochemical and biological properties of soils require accentuated scientific attention, particularly with respect to significant feedback processes to climate and soil services such as food security.
Authors:W. J. Duan, Q. Liu, R. X. Zhao, Y. Mu, L. P. Guo, D. P. Li and X. Wang
A method was developed for the preparative separation of two alkaloids from the crude extract of the radix of Rauvolfia verticillata (Lour.) Baill. in a single run. The two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:2:8, v/v), where triethylamine (40 mmol/L) was added to the upper organic phase as the stationary phase and hydrochloric acid (10 mmol/L) was added to the lower aqueous phase as the mobile phase, was selected for this separation by pH-zone-refining counter-current chromatography (PZRCCC). For the preparative separation, the apparatus was rotated at a speed 850 rpm, while the mobile phase was pumped into the column at 2 mL/min. As a result, 112 mg of reserpine and 21 mg of yohimbine were obtained from 3 g of crude extract in a single run. The analysis of the isolated compounds was determined by high-performance liquid chromatography (HPLC) at 230 nm with purities of over 91.0%, and the chemical identification was carried out by the data of electrospray ionization–mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR) spectroscopy. The technique introduced in this paper is an efficient method for preparative separation of reserpine and yohimbine from devil pepper radix. It will be beneficial to utilize medicinal materials and also useful for the separation, purification, and pharmacological study of Chinese herbal ingredients.
Hypoxis (Hypoxidaceae) consists of about 90 species of plants reported worldwide, of which 76 occur in Africa. As many as 41 species are indigenous to countries belonging to the Southern African Development Community (SADC), including South Africa. Of all the Hypoxis species, Hypoxis hemerocallidea has versatile application in traditional health care system of over 85% of South Africans and is regarded as one of the most ethnomedicinally important and most marketed species in South Africa. H. hemerocallidea corm’s water or alcoholic extract is widely used as traditional medicine for the treatment of benign hypertrophy and urinary tract infections as well as for boosting the immune system of people living with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) among others. However, the use of other parts of Hypoxis plant as medicine is vital for conservation purposes. The roots attached on the corm of H. hemerocallidea contain hypoxoside, but the roots are usually ripped off during the preparation of Hypoxis-containing traditional medicines and other herbal products. A developed and validated, affordable but reliable high-performance thin-layer chromatography (HPTLC) densitometry for the rapid and repeatable visualization and quantitative determination of hypoxoside from the roots of H. hemerocallidea was performed. After thin-layer chromatography analysis, the hypoxoside resolved and was visualized at RF of 0.30 in CHCl3‒MeOH‒H20 (70:30:2 v/v). The method was linear with R2 of 0.9876 over a calibration range of 0.20 × 10−4–1.80 × 10−3 mg mL−1. The limits of detection (LOD) and quantification (LOQ) were 5.08 × 10−4 and 1.65 × 10−3 mg mL−1, respectively, while the percentage recovery and the method repeatability (%RSD) were 84.10 and 4.98, respectively. The roots of H. hemerocallidea were found to contain 4.101 × 10−4 mg mL−1 of hypoxoside.
Authors:Sagnik Haldar, Satyabrata Mohapatra, Rahul Singh and Chandra Kant Katiyar
Asparagus racemosus has been gaining importance due to its recently detected pharmacological activities. There has been a need to develop a simple isolation method for the major bioactive phytochemical and its quantitative evaluation in the herb. Hence, a rapid, sensitive, and reproducible high-performance thin-layer chromatography (HPTLC) method has been developed for determining its major bioactive marker, shatavarin IV. HPTLC silica gel F254 pre-coated plates were used with ethyl acetate‒methanol‒water (7.5:1.5:1, v/v) as the mobile phase. The plates were developed to a distance of 60 mm at 23 ± 4°C in twin-trough chamber, previously saturated for 5 min. Under these conditions, the retention factor (RF) of shatavarin IV was 0.43 and it was quantified at 425 nm, the wavelength of maximum absorbance after derivatization in anisaldehyde‒H2SO4 reagent. Shatavarin IV showed a linear function of amount 600 to 1800 ng per band; the correlation coefficient was 0.9934, indicating a good relationship between peak area and amount. The limits of detection (LOD) and quantitation (LOQ) were 14.35 ng and 43.50 ng, respectively. The method was validated for precision, repeatability, and accuracy. Recovery was determined by spiking samples with shatavarin IV before extraction and it was found to be 96.17%. Shatavarin IV was found to be present in roots (0.40%) and in enriched fraction (61.20%).
Remimazolam is a new chemical entity belonging to the benzodiazepine class of sedative drugs. A sensitive and rapid method based on ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) has been developed and validated for the determination of remimazolam and its major carboxylic acid metabolite (M1) in human urine. Urine samples were prepared by dilution and analyzed using an isocratic chromatographic separation. Inter- and intra-batch results for remimazolam were within 10.7% for accuracy and 5.5% for precision, and for M1, within 5.8% for accuracy and 4.2% for precision, respectively. This study represents the first reported example for the quantification of remimazolam and its main metabolite in human urine. Furthermore, this method has been successfully applied for the urine recovery study of remimazolam in Chinese healthy subjects. Only about 0.01% of the administered remimazolam dose was eliminated in the urine over the 24 h period in the form of unchanged remimazolam, and more than 75.1% of the administered dose was eliminated in the form of M1. Remimazolam is excreted mainly in the form of M1 in urine after intravenous administration, and there is no excessive accumulation in vivo after administration of remimazolam.
Authors:Emese Szabó, László Huzsvai, Rita Kremper and Jakab Loch
The traditional Hungarian method for determining soil phosphorus (P) status is ammonium-lactate acetic acid (AL) extraction. AL is an acidic solution (buffered at pH 3.75), which is also able to dissolve P reserves, so there is a need for extraction methods that also characterize the mobile P pool.
0.01 M CaCl2-P is considered to directly describe available P forms, because the dilute salt solution has more or less the same ionic strength as the average salt concentration in many soil solutions.
The amount of AL-P may be two orders of magnitude greater than that of CaCl2-P. Previous studies suggested that the relationship between AL-P and CaCl2-P was influenced by soil parameters. Regression analysis between AL-P and CaCl2-P showed medium or strong correlations when using soils with homogeneous soil properties, while there was a weak correlation between them for soils with heterogeneous properties.
The objective of this study was to increase the accuracy of the conversion between AL-P and CaCl2-P, by constructing universal equations that also take soil properties into consideration.
The AL-P and CaCl2-P contents were measured in arable soils (n=622) originating from the Hungarian Soil Information and Monitoring System (SIMS). These soils covered a wide range of soil properties.
A weak correlation was found between AL-P and CaCl2-P in SIMS soils. The amounts and ratio of AL-P and CaCl2-P depended on soil properties such as CaCO3 content and texture. The ratio of AL-P to CaCl2-P changed from 37 in noncalcareous soils to 141 on highly calcareous soils. CaCl2-P decreased as a function of KA (plasticity index according to Arany), which is related to the clay content, while the highest AL-P content was found on loam soils, probably due to the fact that a high proportion of them were calcareous.
The relationships between AL-P, CaCl2-P and soil properties in the SIMS dataset were evaluated using multiple linear regression analysis. In order to select the best model the Akaike Information Criterion (AIC) was used to compare different models. The soil factors included in the models were pHKCl, humus and CaCO3 content to describe AL-P, and KA, CaCO3 content and pHKCl to describe CaCl2-P. AL-P was directly proportional to pHKCl, humus and CaCO3 content, while CaCl2-P was inversely proportional to KA, CaCO3 content and pHKCl. The explanatory power of the models increased when soil properties were included. The percentage of the explained variance in the AL-P and CaCl2-P regression models was 56 and 51%, so the accuracy of the conversion between the two extraction methods was still not satisfactory and it does not seem to be possible to prepare a universally applicable equation. Further research is needed to obtain different regression equations for soils with different soil properties, and CaCl2-P should also be calibrated in long-term P fertilization trials.
Authors:P. R. Desai, P. J. Mehta, S. K. Ojha and A. B. Chokshi
A novel, simple, robust, and rapid reversed-phased high-performance liquid chromatographic method has been developed for the separation and quantitative determination of the related substances of ezetimibe and simvastatin in combined dosage forms. Successful separation of the drug from the process-related impurities and degradation products formed under stress conditions was achieved on Inertsil ODS-3V (150 × 4.6 mm, 5.0 μm) column. The gradient liquid chromatography (LC) method employs solution A and solution B as mobile phase. The solution A contains 0.1% orthophosphoric acid solution in water, and solution B contains 0.1% orthophosphoric acid solution in acetonitrile. Flow rate was monitored at 2.0 mL/min, and the ultraviolet (UV) detection, at 238 nm. In forced degradation studies, the effect of acid, base, oxidation, UV light, and temperature was investigated, showing that good resolution between the peaks corresponds to process-related impurities and degradation products from both analyte. The performance of the method was validated according to the present International Conference on Harmonization (ICH) guidelines for specificity, limit of detection, limit of quantification, linearity, accuracy, precision, ruggedness, and robustness. To the best of our knowledge, a rapid LC method, which separates all the impurities of ezetimibe and simvastatin in combined dosage forms, disclosed in this investigation was not published elsewhere.
Authors:János Jóvér, Elza Kovács, Péter Riczu, János Tamás and Lajos Blaskó
One option for adaptation to climate change is to grow a wider variety of plant species. Sorghum (Sorghum bicolor (L.) Moench) is known to tolerate unfavourable environmental conditions, so it may be feasible to grow it on areas with extreme conditions to replace other species such as maize. Nowadays, spatial decision supporting systems primarily support the crop production process rather than crop structure adjustment. In this study, potential sorghum production sites in the Great Hungarian Plain were selected based on soil characteristics including genetic soil type, parent material, physical soil type, clay composition, water management, pH, organic matter content, topsoil thickness and fertility, as well as climatic data, particularly precipitation. For all the parameters the aim was to find the extreme values at which sorghum, which is less sensitive than maize, may still give an acceptable yield. By combining map layers of soil characteristics, it could be concluded that although the soil is suitable for sorghum on 40.46% of the Great Hungarian Plain, maize is generally a better choice economically. On the other hand, the soil conditions on 0.65% of the land are still suitable for sorghum but unfavourable for maize. As regards the precipitation demand of sorghum, May is the critical period; on 698,968 ha the precipitation required for germination was only recorded once in the period 1991-2010, so these areas cannot be considererd for sorghum. As a consequence, in an alternative crop rotation system sorghum could be competitive with maize, but both the soil and climate conditions and the demands of the crop need to be assessed. The lack of precipitation in critical phenophases significantly decreases the area where maize can survive. Sorghum, however, may produce an acceptable yield, as it is a drought-resistant species.
The present article discusses the applicability of thermoanalytical methods in the analysis of Hungarian soils formed on carbonate rocks. Up to now only limited mineralogical and soil chemical research has been done on these soils. Soils from the Bükk Mountains, the most varied limestone region in Hungary, were used for the investigations. The aim was to extend our incomplete knowledge on the mineral composition and formation processes of these soils and to demonstrate the possibilities and evaluation potential of thermoanalytical techniques. All the soils investigated were formed on limestone and had different surface soil thickness, influenced by the accumulation of silicate debris and the microterrain. The results of soil mineralogical analysis revealed an extraordinarily high proportion of quartz compared to that of other minerals (especially calcite), indicating that these soils could not have originated solely from the weathering of the limestone bedrock. The results also showed that thermoanalytical methods could complement classical chemical and instrumental (XRPD) methods in research on the genesis of soils formed on limestone.
Authors:Mamdouh R. Rezk, Abd El-Aziz B. Abd El-Aleem, Shaban M. Khalile and Omneya K. El-Naggar
Lavender and rosemary are shrubs that have many medicinal uses. Like any other shrubs, they are susceptible to pest infection which needs pesticides treatment. Residues of pesticides in lavender and rosemary leaves may be hazardous to human health. The main objective of this study was to develop accurate and sensitive methods for the determination of residues of pesticides, namely, diazinon and chlorpyrifos, in lavender and rosemary leaves. Thin-layer chromatography (TLC) fractionation was applied to separate the desired pesticides to be analyzed and to determine the rate of the disappearance of these pesticides from lavender and rosemary leaves. Diazinon and chlorpyrifos were separated from extracts of leaves using silica gel 60 F254 plates. The mobile phase was formed of petroleum ether–ethanol–glacial acetic acid (9.5:0.5:0.1, v/v) and (9.0:1.0:0.1, v/v) as the developing systems for diazinon and chlorpyrifos, respectively, followed by densitometric measurement at 254 nm for both pesticides. The methods were validated over a range of 0.01–l.6 μg band−1 for diazinon and 0.04–2.0 μg band−1 for chlorpyrifos. The detection limits of diazinon and chlorpyrifos were 0.003 and 0.012 μg band−1, respectively. The safe harvest interval (pre-harvest interval; PHI), time in days between the last pesticide application to the crop and the time it can be safely harvested, was suggested to be 21 and 24 days for diazinon and chlorpyrifos, respectively. The developed TLC methods were used for sample cleanup and estimation of the studied pesticides residues in leaves extracts, in addition to the determination of the pre-harvest interval.
Authors:Zhaojun Sheng, Ruhan Ye, Siyuan Ge, Chenggang Wang, Xuetao Xu, Guangwen Zhang and Ping Luo
An efficient and convenient reversed-phase high-performance liquid chromatography method has been developed and validated for the quantitative determination of cholic acid bulk drugs and their related impurities. Chromatographic separation was performed on a YMC-Pack ODS-AQ column (250 mm × 4.6 mm, S-5 μm, 12 nm), and the mobile phase consisted of acetonitrile, methanol, and diluted formic acid solution (pH 2.5) at a flow rate of 1.0 mL/min. The analytes were monitored using a refractive index detector at 30 °C, and the column temperature was 30 °C. Under the above chromatographic conditions, the method has good specificity and specified impurities can be effectively separated. The proposed method is found to have linearity in the 2.0–80.0 μg/mL concentration range with correlation coefficients of not less than 0.9999. The compounds analyzed in the solutions are stable for at least 7 days, and spike recoveries for all specified impurities range from 91.3% to 109.3% with relative standard deviations (RSDs) not more than 7.3%. The limit of detection and the limit of quantification for the analytes are 0.060 μg/mL and 2.0 μg/mL, respectively. The proposed method can be applied in the quality control assay of cholic acid bulk drugs, with the advantages of simplicity, accuracy, robustness, good selectivity, and high sensitivity.
The present research evaluated the chemical composition as well as the antioxidant and antimicrobial properties of the essential oil from the bark of Ocotea quixos (Lam.) Kosterm. The major components of the essential oil were cinnamaldehyde <(E)-> (30.69%), methoxy cinnamaldehyde <(E)-o-> (16.29%), cinnamyl acetate <(E)-> (12.18%), and methyl cinnamate <(E)-> (5.72%). The antioxidant capacity showed to be superior to that of the essential oil of Tymus vulgaris. The results show low half maximal inhibitory concentration (IC50) values, which means that the essential oil has a high activity: 2,2-diphenyl-1-picrylhydrazyl (DPPH) IC50, 2.786 ± 0.150 mg mL−1; 2,2′-azino-di-(3-ethylbenzthiazoline sulfonic acid (ABTS) IC50, 0.240 ± 0.034 mg mL−1; and IC50 β-carotene test, 0.496 ± 0.017 mg mL−1. The essential oil was active with all the microorganisms evaluated, being very active against: Escherichia coli ATCC (American type culture collection) 25922, Staphylococcus aureus ATCC 29213, Listeria grayi ATCC 19120, Micrococcus luteus ATCC 4698, Trichophyton mentagrophytes ATCC 9533, and Trichophyton rubrum ATCC 13803. The bioautography assays showed that bergamoteno <α-trans-> and methoxy cinnamaldehyde <€-o-> were the responsible molecules for the antioxidant activity and cinnamyl acetate <€-> was the molecule responsible for the antimicrobial activity.
The aim of this work was the application of thin-layer chromatography to the lipophilicity analysis of selected quinobenzothiazine derivatives. These are newly synthesized compounds, which were previously analyzed taking into consideration biological activity and their antiproliferative activity. Experimental lipophilicity parameters (RM0 and log PTLC) were determined by use of thin-layer chromatography, and also some theoretical values of lipophilicity were calculated by use of computer programs. The correlation between the experimental and the theoretical values of lipophilicity was found. Also, cluster analysis was performed for the data obtained. Phenothiazine derivatives were modified mainly by introduction of substituents into the nitrogen atom of the thiazine ring. The computer programs applied based on different theoretical approaches gave different values of lipophilicity parameters depending on the kind of substituent in the quinobenzothiazine system. None of the computer programs took into consideration the influence of substituents in a structure of the tested compounds, and in this case, the calculated lipophilicity parameter had the same value for all isomers with the same substituent. Also, none of the computer programs gave values of lipophilicity parameters close to these obtained by experimental method. The results of log Pcalc for the compounds 1–13 were quite different according to the computer program used (log Pcalc = 1.69–5.98). No computer programs gave values of log Pcalc close to values of log PTLC obtained experimentally. The reason can be the specific special structure of the tested phenothiazine derivatives consisting of tetracyclic system with additional nitrogen atom. It shows that calculation methods can be useless for the preliminary lipophilicity determination of such a kind of compounds.
Authors:Raman Preet, Raghbir Chand Gupta and Saroj Kumar Pradhan
Among the complex mixture of biologically active compounds in Leptadenia pyrotechnica, three compounds have been used as analytical markers. A sensitive high-performance thin-layer chromatographic (HPTLC) method has been developed for the estimation. Methanolic extracts of whole plants from three populations were used on aluminum pre-coated silica gel 60 F254 plates with different mobile phases to determine the amount of β-sitosterol, lupeol, and oleanolic acid with RF value of 0.64, 0.84, and 0.47, respectively. The calibration curve was linear in the range of 2–10 μg. The method is reliable for the quantification, separation, and good resolution of these compounds from other constituents of L. pyrotechnica. To ascertain the purity of the peak from the test sample, its in-situ reflectance spectrum was compared with that from standards; the clear superimposability indicated the purity of the peaks.
A simple, sensitive, and precised high-performance thin-layer chromatography (HPTLC) method has been developed for the analysis of lawsone in natural vis-à-vis micropropagated plant parts of Lawsonia inermis L. Separation of the components was perfectly achieved on high-performance thin-layer chromatography (TLC) plates using optimized tertiary mobile phase of benzene‒ethyl acetate‒ acetic acid (7.5:2.5:0.1, v/v). Densitometric scanning was performed before derivatization of the plate in absorption/reflection mode, and lawsone was quantified at its maximum absorbance of wavelength of 275 nm. Linearity of the method was obtained in the concentration range of 50 to 350 ng spot−1 with a correlation coefficient (r2) of 0.9999, indicating good relationship between concentrations in opposition to the peak area. The limit of detection and limit of quantification were found to be 16 and 50 ng spot−1, respectively. The obtained recovery ranges from 95.09% to 96.90% with an average value of 96.02% proved the excellent accuracy of the method. The developed method was found to be highly sensitive, and the mobile phase enables outstanding separation of lawsone from other components present in the mixture. The International Conference on Harmonization (ICH) guidelines were followed for validation of the HPTLC method in terms of precision, repeatability, and accuracy. The maximum content of lawsone was reported in the leaves of the micropropagated plant.
Authors:Renuka Munshi, Namrata Gawde, Salman Dalal and Deepali Ganachari
A simple and reliable high-performance thin-layer chromatographic (HPTLC) method has been developed and validated for the determination of topiramate in human serum which will help in therapeutic drug monitoring that aids in the clinical management of patient therapy. This method uses dipping method of derivatization to make the non-chromophore topiramate visible for detection. Pre-coated silica gel F254 HPTLC plates were used to carry out chromatographic separation using a mixture of toluene–ethanol (9:1) as the mobile phase. Derivatization was carried out using dipping method. Betamethasone was used as internal standard. Densitometric detection was carried out at 417 nm. The method was validated for linearity, precision, selectivity, limit of detection and limit of quantification and accuracy. Linear calibration curves in the range of 0.25 to 40 μg band−1 gave a correlation coefficient of 0.9963. The intra-day (n = 6) and inter-day (n = 18) precision, expressed as the relative standard deviation, were in the range of 2.89% to 3.41% and from 2.97% to 4.20%. The limit of detection and the limit of quantification were found to be 0.36 μg band−1 and 1.10 μg band−1. The accuracy was calculated as percentage recovery and was found to be 97.41% and 110.7%. The method was specific and showed no matrix interference. Compared to other methods employed in the determination of topiramate from blood, this method is cost-effective, simple, and reliable to carry out therapeutic drug monitoring of topiramate.
Presently, sterols like stigmasterol, β-sitosterol, campesterol, and ergosterol are identified and quantified from leaves, stem, and inflorescence of Heteropogon contortus. (L.) Beauv (family: Poaceae) from Rajasthan, India, using high-performance thin-layer chromatography (HPTLC). H. contortus is reported with various medicinal properties. In the present study, a HPTLC–densitometric method was developed for the quantification of sterols by using toluene‒methanol‒formic acid (9:1:0.3 v/v) as the mobile phase. Post-derivatization of the plates was done by using freshly prepared anisaldehyde–sulfuric acid, heated at 110–120°C and scanned at 530 nm absorbing wavelength. The maximum contents of stigmasterol, campesterol, and ergosterol were estimated in inflorescence extracts (11.64 ± 017, 19.90 ± 0.18, and 16.64 ± 0.81 mg g−1 of dry wt. w/w, respectively), whereas β-sitosterol was found maximum in leaves, i.e., 56.52 ± 1.25 mg g−1 of dry wt (w/w). This HPTLC method is found to be simple, precise, specific, sensitive, and accurate. It can be easily used in the routine quality control of raw materials.
Authors:Dominik Mieszkowski, Wiktor Dariusz Sroka and Michał Piotr Marszałł
High-performance thin-layer chromatography (HPTLC)–densitometric method of haloperidol (HP) and its two metabolites (reduced haloperidol [RHP], 4-(4-chlorophenyl)-4-hydroxypiperidine [CPHP]) from human plasma has been developed by use of mobile-phase additives. The influence of the type of inorganic/ organic additive on the retention of the studied compounds was evaluated. The chromatographic process was carried out with traditional mobile phase modifiers and 1-alkyl-imidazolium ionic liquid as separation enhancers, in the presence of chlorpromazine as internal standard. 1-Ethyl-3-methylimidazolium tetrafluoroborate ([emim][BF4]) ionic liquid offered good selectivity in comparison with traditional mobile phase additives. The studied drugs were well distributed as the RF values were 0.31 for chlorpromazine hydrochloride (CPZ), 0.38 for HP, 0.44 for CPHP, and 0.58 for RHP, respectively, with no apparent broadening and overlapping of spots. The test compounds were extracted using acetonitrile as precipitation agent. The identity of the bands from human plasma was additionally confirmed by rapid and contamination-free CAMAG thin-layer chromatography–mass spectrometry (TLC–MS) interface. The limit of detection (LOD) values obtained by densitometry scanning were 0.1807, 0.3158, and 0.3924 μg spot−1 (for HP, RHP, and CPHP), whereas the limit of quantification (LOQ) values for the presented method were 0.5476, 0.9570, and 1.1892 μg spot−1 (for HP, RHP, and CPHP). Recovery values of all tested compounds were in the range from 95.43% to 99.60% (intra-day) and 96.13% to 103.18% (inter-day); %RSD did not exceed the value of 5%. The results confirm the positive effect of ionic liquids in the separation process related to their silanol blocking properties and their suitability for use in thin-layer chromatography/mass spectrometry method.
A sensitive, reliable, and rapid densitometric high-performance thin-layer chromatography (HPTLC) method has been developed for the quantification of hydroxysafflor yellow A (HSYA) in safflower. Chromatographic analysis was performed using the methanol extract of safflower. Polyamide TLC plates were used with the solvent system containing 3.6% hydrochloric acid, methanol, and ethyl acetate (7:3:1, v/v). Densitometric analysis of HSYA was performed at the absorbance mode of 399 nm. This system was found to give compact and dense spots for HSYA (RF value of 0.60 ± 0.03). The method showed a good linear relationship in the range of 61.0– 79.3 ng with r = 0.9991. The limit of detection, limit of quantification, and average recovery were 59 ng, 169 ng, and >95%, respectively. The proposed validated HPTLC method is an easy-to-use, accurate, and convenient method that can be successfully used for the standardization and quality analysis of herbal materials with different species of safflower.
Authors:Joanna Nowakowska, Krzesimir Ciura, Piotr Kawczak, Bartosz Wielgomas and Tomasz Bączek
Synthetic pyrethroids are pesticides derived from naturally occurring pyrethrins. Nowadays, they are one of the most commonly used insecticides. Synthetic pyrethroids are applied in many areas including agriculture, veterinary medicine, households, and public health. The chromatographic properties of 7 synthetic pyrethroids with known lipophilicity have been studied by use of planar chromatography. Reversed-phase and normal-phase thin-layer chromatography approaches were applied. The main goal of this study was to evaluate retention parameters as the possible measure of the lipophilicity of synthetic pyrethroids. Upon the obtained results, it can be concluded that the best chromatographic system to predict log P is reversed-phase thin-layer chromatography and a mixture of tetrahydrofuran and water (r = 0.972). This conclusion was also confirmed by the performed principal component analysis. Furthermore, the utilization of computational descriptors, calculated by Dragon software, showed which physicochemical properties of molecules govern the retention in normal-phase thin-layer chromatography.
Authors:Prawez Alam, Y.T. Kamal, Mohammed H. Alqarni, Hala H. Zaatout and Maged S. Abdel-Kader
A new rapid, simple, economical, and environment-friendly reversed- phase high-performance thin-layer chromatography (RPHPTLC) method has been established for the simultaneous determination of glycyrrhizin and glabridin in Glycyrrhiza glabra roots, rhizomes and selected herbal formulations. The method was carried out using RP-18 silica gel 60 F254S HPTLC glass plates and methanol–water (7:3 v/v) as the mobile phase. The developed plates were scanned and quantified densitometrically at 256 and 233 nm for glycyrrhizin and glabridin, respectively. Glycyrrhizin and glabridin peaks from G. glabra roots and rhizomes and herbal formulations were identified by comparing their single spots at RF = 0.63 ± 0.02 and RF = 0.28 ± 0.01, respectively. Linear regression analysis revealed a good linear relationship between the peak areas and the amounts of glycyrrhizin and glabridin in the ranges of 1000–7000 and 100–700 ng band−1, respectively. The method was validated, in accordance with the International Conference on Harmonization (ICH) guidelines for precision, accuracy, and robustness. The proposed method will be useful to determine the therapeutic doses of glycyrrhizin and glabridin in herbal formulations as well as in bulk drug.
Authors:Roshdy E. Saraya, Randa A. Abdel Salam and Ghada M. Hadad
A new, simple, precise, accurate, stability-indicating, and rapid high-performance thin-layer chromatography (HPTLC) method was developed and validated for the determination of ondansetron hydrochloride in pure form and pharmaceutical formulations. The method used Merck HPTLC aluminum plates precoated with silica gel 60 F254 as the stationary phase. The mobile phase consisted of chloroform–methanol–ethyl acetate (7:2:1, v/v). This system was found to give a compact spot of ondansetron (RF value of 0.67 ± 0.011); ondansetron was subjected to acid and alkali hydrolysis, oxidation, and photodegradation. The wavelength of TLC scanner was set at 302 nm for both detection and quantitation. The calibration curves were linear over the range of 25–500 ng spot−1. The limit of detection was 4.9 ng spot−1, and the limit of quantitation was 14.7 ng spot−1. The proposed analytical method was validated according to the International Conference on Harmonization (ICH) guidelines, and the results were acceptable. The proposed method has been successfully applied to the determination of the studied drug in its pharmaceutical preparations and it gave excellent % of recovery. The results showed excellent agreement with the reported method with respect to precision and accuracy.
Authors:Yonggang Li, Xiaohong Liu, Rui Zhang, DerGer ZomPa, Ping Luo, Lin Tang, Xiao Liu, Yan Zhou and Sheng Wen
A reliable isotope dilution method for the determination of chloramphenicol (CAP) in drinking water was developed by using an evaporation preparative step. Each sample was monitored by ultrahigh-pressure liquid chromatography (UHPLC) coupled to tandem mass spectrometry (MS/MS) using an electrospray ionization interface (ESI) in negative ion modes. Recoveries of spiked samples were in the range from 93.2% to 95.7% with intra-day relative standard deviation lower than 6.7% and inter-day relative standard deviation lower than 8.2%. Limit of quantification (LOD) was 0.002 ng/mL. The developed method was successfully applied to the analysis of CAP in drinking water of Shannan region of Tibet.
Authors:Ebru Büyüktuncel, Esra Porgalı and Serpil Özkara
A new molecularly imprinted polymer (MIP) was prepared by using catechin (C) as the template molecule. The polymer was characterized by swelling tests, scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), and Fourier transform infrared (FTIR) spectroscopy. The MIP with high recovery was selected as a solid-phase extraction (SPE) sorbent in this work. The standard solutions were directly applied onto the SPE cartridges following loading, washing, and elution procedures. A solution of the collected fractions was analyzed by high-performance liquid chromatography–diode-array detection (DAD) and fluorescence detector. The optimization of the method and validation was achieved on a C18 column (5 μm, 250 × 4.6 mm) with methanol–water (35:65, v/v) mixture adjusted pH 2.5 as the mobile phase at a flow rate of 1 mL min−1 at room temperature. The selectivity coefficient (k) of imprinted p(HEMA–MAH) cryogel was 5.1-fold that of non-imprinted cryogel. It showed good selectivity and affinity for C molecule. A comparison was made between the results obtained with the MIP cartridges and a traditional C18 reversed-phase cartridge. It was observed that 2.3 times higher recovery of C can be obtained on catechin-MIP cryogel. The results of the presented work showed that the prepared MIP can be used as SPE sorbent for extracting of C from red wines.
Novel magnetic solid-phase extraction using carboxylated multiwalled carbon nanotubes was proposed with ultra high-performance liquid chromatography–tandem mass spectrometry for the determination of silodosin in biological samples. The effects of various experimental parameters including adsorbent amount, pH, adsorption time, desorption conditions, and adsorbent reusability were systematically validated. Under the optimized conditions, the calibration curve was linear within the concentration range of 1.0–800 ng mL−1 with the correlation coefficient of 0.9997 and the lower limit of detection was 0.3 ng mL−1. The extraction recoveries were over 90.0% with relative standard deviation (RSD) of less than 5.0%. All these results suggested that magnetic extraction method can be used for enrichment and quantification of silodosin in biological samples.
Authors:Liyi Li, Liming Hu, Bingbao Chen, Yanwen Dong, Zixia Lin, Zhiyi Wang, Congcong Wen, Xianqin Wang and Shuanghu Wang
In this study, we developed a urine metabolomic method by gas chromatography–mass spectrometry (GC–MS) combination with biomedical results to evaluate the effect of activated carbon on methomyl poisoning rats. The rats were divided into four groups, methomyl group, two activated carbon treatment group, and control group. According to the biochemical results, it indicated that activated carbon treated rats could cause liver and kidney function changes. According to the urine metabolomics results, activated carbon treatment group (10 min) and activated carbon treatment group (30 min) could be distinguished from methomyl group, and activated carbon treatment group (10 min) could be separated from activated carbon treatment group (30 min) rats, which indicated that the treatment of rats by activated carbon in different time had a different effect. The results indicate that metabolomic method by GC–MS may be useful to elucidate activated carbon treated on methomyl poisoning rats.
Authors:Shuanghu Wang, Zixia Lin, Ke Su, Jing Zhang, Lijing Zhang, Zhimou Gao, Zhiyi Wang, Jianshe Ma and Xianqin Wang
The rats were randomly divided into paraquat group, curcumin treatment group, and pirfenidone treatment group. The concentration of paraquat in rat plasma was determined by an ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method over the range of 10–2000 ng mL−1. Chromatographic separation was achieved on a BEH HILIC (2.1 mm × 100 mm, 1.7 μm) column. The mobile phase was consisted of acetonitrile and 10 mm ammonium formate buffer (containing 0.1% formic acid) with gradient elution pumped at a flow rate of 0.4 mL min−1. Protein precipitation with acetonitrile was used as sample preparation. Compared with the paraquat group, there is statistical toxicokinetic difference for curcumin treatment group and pirfenidone treatment group, AUC(0 − t) decreased (P < 0.05), clearance (CL) increased (P < 0.05) for curcumin or pirfenidone treatment group, and Cmax decreased (P < 0.05) for curcumin treatment group. The results showed that treatment by curcumin and pirfenidone could relieve acute paraquat poisoning in rats.