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The use of organic fertilization is declining in Hungary due to the sharp fall of livestock stand since the middle of the 1980s. Most farmers are forced to use solely chemical crop enhancers. A bifactorial small plot experiment was carried out between 10 May 2023 and 19 October 2023 in Keszthely, in order to examine the effects of farmyard manure (M), green manure (GM) and stem residues (SR) on the nutrient uptake and nitrogen utilization efficiencies of maize at equidistantly increasing (0–70–140–210–280 kg N ha–1) nitrogen doses. The relationship between some vegetative traits (dry biomass weight, Leaf Area Index (LAI)) and yield, furthermore leaf relative water content (RWC) was also examined. According to the results, organic fertilizer substitution significantly increased the N content both in whole plant and grain samples of NPK+M and NPK+GM+SR treatments, compared to the chemically fertilized control (NPK). In case of P and K only slight differences were observed. Whole plant K contents of NPK+M were significantly higher than in the other treatments (P = 0.045; P = 0,005), furthermore P contents in grain samples were significantly higher in NPK+M (P = 0.004) and NPK+GM+SR (P = 0.05) than in control. Harvest index (HI [%]) of NPK+M and NPK+GM+SR were 1.06 and 1.05 times higher than in NPK. Depending on the treatment, P0023 maize hybrid absorbed 58.7–74.64% of total N uptake in the grain (HIN%), and the utilization of 1 kg N fertilizer for the extra yield above the yield of the individual control was 0.39–1.38 kg (AREN). Significant positive correlations were observed between dry biomass weight and yield (NPK: r = 0.937, P = 0.019; NPK+M: r = 0.971, P = 0.006; NPK+GM+SR: r = 0.88, P = 0.049), furthermore LAI and yield (NPK: r = 0.9, P = 0.037; NPK+M: r = 0.983, P = 0.003; NPK+GM+SR: r = 0.784, P = 0.117). Highest RWC values – which may be related to better soil aggregate stability – were measured in NPK+GM+SR treatment, therefore there may be a great potential in this treatment among drought conditions. The effect of organic amendments is particularly noticeable with smaller nitrogen doses so they should be used to reduce inorganic fertilizer application and the resulting environmental risks.

Open access

Abstract

A simple, fast and selective analytical method has been developed for the simultaneous determination of allantoin and D-panthenol in cosmetic products containing Aloe vera extracts. The proposed method depends on reversed-phase liquid chromatography with isocratic flow profile of the mobile phase composed of acetonitrile–10 mM phosphoric acid (pH 2.5) (85:15, v/v), with a C18 column at 30 °C. The analytes were detected with UV–vis. detector at 210 nm. The injection volume was 20 μL. The linearity ranges were found to be 0.2–20 and 0.1–10 μg mL−1 for allantoin and D-panthenol, respectively. LOD values were found to be 0.07 μg mL−1 and 0.03 μg mL−1, LOQ values were found to be 0.2 and 0.1 μg mL−1 for allantoin and D-panthenol, respectively. No interference was observed from concomitants. The developed method was applied to the analysis of 10 different type cosmetic products. It is foreseen that the method will be able to be used in order to carry out routine analysis, quality control and standardization in cosmetic products containing allantoin and D-panthenol.

Open access

Abstract

A simple, rapid, and green high-performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed for determination of tauroursodeoxycholic acid (TUDCA), taurocholic acid (TCA), and taurochenodeoxycholic acid (TCDCA) in bio-transformed Jindanfen (BTJDF), which is obtained from chicken bile through a bioconversion process. The sample was prepared using water. The HPLC separation was operated on a poroshell 120 EC-C18 column with a 2.0 min gradient elution procedure. Detection was performed on a single quadrupole mass spectrometer in negative mode with selected ion monitoring mode (SIM). This developed HPLC-MS method presented good linearity (r > 0.997) and sensitivity (limit of quantification, 30.0–80.0 pg) for three analytes. The relative standard deviations (RSDs) for precision, repeatability, and stability were all below 3.00%. The matrix effects and average recoveries of three analytes were 91.2–97.9% (RSDs < 1.50%) and 95.4–103% (RSDs < 3.00%), respectively. The average contents of TUDCA, TCA, and TCDCA in ten batches of samples were 33.8, 13.2, and 20.5%, respectively. Finally, the greenness of the developed method was validated by Analytical Eco-Scale and Complex-GAPI. The developed method was proved to be an eco-friendly, effective, and reliable approach for assaying the three cholic acids in BTJDF, which is help to improve the quality evaluation level of the BTJDF industry.

Open access

Abstract

The current technologies for substandard and counterfeit drug detection are either too expensive for low-resource settings or only provide qualitative or semi-quantitative results. GPHF minilab™ is one of them based on thin layer chromatography(TLC) principles with a semi-quantitative capability by visual observation of the spot area and intensity for medicine quality analysis. Thus, its use as a quality control tool for pharmaceutical products has limitations as spot area and intensity visual observation by the naked eye highly varies from analyst to analyst. As such, in this study, the semi-quantitative technique has been transferred to a quantitative approach by capturing the developed TLC plate image using an Android-based mobile phone inside a simple carton box. Then, the spot area was quantified using justTLC software. The quantitative results were compared with the-high performance liquid chromatography (HPLC) method as the golden standard. Accordingly, linearity was observed in the assayed range (80–120% label claim), and the correlation coefficients found were (R 2 = 0.958, 0.997, 0.941, and 0.956 for Albendazole, Mebendazole, Artemether, and Lumefantrine, respectively.). The values are satisfactory. The %RSDs found were less than 2% for all drugs [intraday (n = 6) (RSD = 1.17, 1.61, 1.87, and 1.64), and interday (n = 18) (RSD = 1.16, 0.72, 1.12, and 1.18) for Artemether, Lumefantrine, Mebendazole, and Albendazole, respectively]. Moreover, comparisons of results obtained from the sophisticated CAMAG UV cabinet (R 2 =0.991, 0.971, 0.946, and 0.967) and the developed simple carton box (R 2 = 0.958, 0.997, 0.941, and 0.956) for Albendazole, Mebendazole, Artemether, and Lumefantrine, respectively. The values are comparable and reveal the accuracy of the method. Robustness testings' that were performed under different altered conditions revealed the robustness of the method (RSD less than 2% for all factors). Additionally the deviations from the golden HPLC results were on average −8.62% for albendazole, −3.79% for artemether, and −4.52% for lumefantrine samples. The developed method shows a satisfactory performance capability to utilize the GPHF minilab™ as a quantitative technique for medicine quality control purposes. It will be a very useful tool in a resource-limited setting. The target method profile, which encompasses a simple, low-cost, linear, precise, robust, accurate, and quantitative GPHF minilab™ system, was obtained for Albendazole, Mebendazole, and Arthemeter lumefantine combinations (Co-artem). The proposed method was successfully applied to analyze the content of the marketed medicines in the above mentioned tablets and offered acceptable deviations from the golden HPLC method. Automation of quantitative GPHF minilab™ was highly recommended to enhance the appropriateness and use of this system.

Open access
Acta Chromatographica
Authors:
Mira Mikulić
,
Darija Sazdanić
,
Nebojša Kladar
,
Jovana Radulović
,
Branislava Srđenović Čonić
, and
Milica Atanacković Krstonošić

Abstract

Due to the frequent use of paracetamol formulations, it is useful to develop an analytical technique for the determination of intact paracetamol in presence of other drugs and excipients or the degradation products. In this study, a simple, isocratic, fast, specific, accurate and precise stability-indicating high performance liquid chromatography (HPLC) method has been developed and validated for simultaneous quantitative determination of paracetamol (PCM) and potassium sorbate (PS) in oral liquid formulations. The chromatographic separation was achieved on Zorbax SB C18 column (150 × 4.6 mm, 5 µm) with Zorbax SB C18 precolumn (12.5 × 4.6 mm, 5 µm) using distilled water pH 2 with ortho-phosphoric acid and acetonitrile (70:30, v/v) as a mobile phase, and UV detection at 235 nm. The temperature of the column was kept constant at 25 °C. The method was validated according to International Conference on harmonization (ICH) guidelines. The method demonstrated excellent linearity, with a correlation coefficient of 0.9996 and 0.9998 for PCM and PS, respectively, over the concentration ranges of 10–600 μg mL−1 (PCM) and 6–500 μg mL−1 (PS). The retention time was found to be 1.98 and 4.86 min for PCM and PS, respectively. Oral liquid formulation samples were subjected to various stress conditions (acidic and alkaline hydrolysis, as well as oxidative, heat and photolytic degradation) for the purpose of forced degradation study. The major degradation of paracetamol was achieved in acidic and basic stress conditions, while thermal and photolytic degradation generally had the least influence. On the other hand, potassium sorbate was highly susceptible to photolytic degradation. It was also shown that the formulation has strong influence on stability of tested compounds. Forced degradation studies demonstrated the stability-indicating power of the method and can be used to assess the stability of paracetamol and potassium sorbate in oral liquid formulations.

Open access

Abstract

Baricitinib (BRT) is a drug substance with potent anti-inflammatory activity indicated in rheumatoid arthritis, atopic dermatitis, severe alopecia areata and recently for the treatment of Covid-19. Process impurities of the drug during its formulation are quite known, however studies regarding its degradation products (DPs) under stress conditions are limited. In this study, the drug was subjected to forced degradation under various degradation conditions, including acidic hydrolysis, alkaline hydrolysis, oxidative and thermal, to determine its inherent stability. To this purpose, a novel HPLC method was developed for the determination of degradation impurities of BRT. Alkaline hydrolysis test showed a selectivity towards breaking C–C bonds. This resulted to five DPs formed by chain scission reactions occurred at the pyrrolo-pyrimidine group between C6–C10 and C8–C9. Also, the ethylsulfonyl-azetidin-ylidene group was subjected to C–C bond cleavage at C12–C15 and C16–C18. Degradation products were further characterized with the use of liquid chromatography quadrupole time of flight tandem mass spectrometry (LC-Q-TOF-MS/MS).

Open access

Abstract

A gradient high-performance liquid chromatography (HPLC) method has been developed to determine the concentrations of latanoprost (LP) and latanoprost free acid (LPA) in aqueous solutions. It is novel due to a combination of its simplicity, speed, and detection capability in aqueous solutions for both active drug (LPA) and prodrug (LP). This method is applicable for the research and development of novel drug delivery devices and quality control assays for experimental and commercial laboratory settings, as it allows for a high sample throughput. Samples were chromatographed across a C18 + 2.7 µm 4.6 × 7.5 mm reversed-phase column with gradient elution using a mobile phase of aqueous acetic acid (pH 3.1) and acetonitrile with 0.1% acetic acid. UV spectrophotometry was used to monitor the eluents at 210 nm. Drug concentrations from 1.0 to 150 μg mL−1 were tested, with good linearity observed across the range. LPA had a signature peak at approximately 4.82 min (SD < 0.08) and LP at 9.27 min (SD < 0.07). For both drug and pro-drug, LOD and LOQ were 1.0 and 2.5 μg mL−1, respectively. This assay which accurately measures both prodrug and drug in a single injection, has significant applicability in determining the release kinetics of novel LP drug delivery systems.

Open access

The rice plant is sensitive to soil salinity. Calcium (Ca) acts as an ameliorative agent that helps plants induce salt tolerance. This study was carried out with a comparison of the ameliorative effect of calcium on salt-stressed rice seedlings, the determination of the role of salt-responsive protein groups, and the analysis of their genetic expressions in 21-day-old rice seedlings of ten locally cultivable varieties of West Bengal. For this study, 15-day-old seedlings were treated with 200 mM of sodium chloride (NaCl) solutions along with 10 mM of calcium sulfate (CaSO4) treatment. The determination of the relationship between the salt-responsive proteins and the analysis of the gene expression of those corresponding proteins were not carried out earlier on the selected ten locally cultivable rice varieties of West Bengal. The NaCl crystals were visible on the abaxial leaf surface of salt-stressed rice seedlings. The superoxide dismutase activity was increased in rice varieties, and a similar result was also expressed with calcium treatment. The fourier transform infrared spectroscopy-attenuated total reflection spectral result gave strong evidence for the presence of several salt-tolerant proteins and their genetic expression. STRING database results have suggested that the calcium treatment, coupled with the expression of the CBL4 protein, has regulated the P5CR protein of proline biosynthesis for better salt tolerance and osmotic protection. The quantitative real-time polymerase chain reaction and SDS-PAGE gel electrophoresis analysis showed that salt-tolerant varieties, Chinsurah_nona_1, and Jarava had high calcium signaling mechanisms and osmo-protection abilities.

Restricted access

Abstract

The advection-convection models (ACM) have practical applications in the investigation of separation processes, where mass (heat) is transferred by convection and diffusion (dispersion) along mass/heat exchanger, eq. adsorption, chromatography column, tubular reactor, etc. The ACM consists of nonlinear partial differential equations which can be solved only with numerical methods. In the article, a comparison of the volume method (VM) and orthogonal collocation on finite elements (OCFE) is presented in terms of their reliability, accuracy of calculations, and speed of calculation. The OCFE proved to be more robust than VM.

The linear ACM model for the chromatography column has an analytical solution in the form of the equation for the number of theoretical plates (N). This equation is often applied in the interpretation and evaluation of model parameters. However, the versions of N equation published in the literature are not correct. The error can lead to significant imprecision for specific cases. Here, in the paper, the revised equations are presented and discussed for the most frequently used chromatography column models.

Open access

Abstract

This study attempted to optimize pectin extraction from queen pineapple (Qp) peels using microwave-assisted method. A three-factor factorial experimental design was employed to test the interaction of moisture content of pineapple peel, pH of the citric acid solution and extraction time. The three-way interaction among the factors has a significant effect on pectin recovery. Two-way interaction between moisture content and pH level, as well as pH level and extraction time caused significant difference in the pectin recovery. Pectin recovery increases with lower moisture content while longer extraction time does not significantly increase pectin recovery. The optimum combination of the parameters is 12% moisture content, pH level 2 of the citric acid solution, and extraction duration of 2 min, which yielded 1.01 ± 0.01% pectin recovery. This is lower than the results from previous studies on pineapple with 3.88–13.06% pectin recovery using acid extraction method. Hence further optimization is recommended.

Restricted access