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Ösztrogének és ösztrogénhatású anyagok a növénytermesztésben
Authors: Eduard Gubó, Pál Szakál and Judit Plutzer

Összefoglalás

Egy vegyület akkor tekinthető ösztrogén hatásúnak, ha alacsony affinitással is, de az ösztrogén receptorokhoz (ER) kötődni képes, az ösztrogén érzékeny sejtekben, szövetekben biológiai hatást képes kiváltani, melyek hasonlóak a petefészek eredetű ösztrogén hormonok által előidézett folyamatokhoz.

Irodalmi adatok alapján a hígtrágyával történő öntözés és intenzív állattartásból származó trágya termőföldre juttatása következtében a szteroid ösztrogének, beleértve az ösztron E1, ösztradiol E2, ösztriol E3, valamint a szintetikus ösztrogén EE2, mindenütt jelen vannak a termőtalajban. A növények felhalmozhatják az ösztrogéneket gyökereikben és hajtásaikban, bekerülve a táplálékláncba akár hatást fejthetnek ki a humán egészségre. A vegyületek ösztrogén potenciálját legtöbbször a 17β-ösztradiol referencia vegyülethez viszonyított relatív potenciálként fejezik ki. Meghatározó szerepe van a vegyületek minőségének, ugyanis az egyes ösztrogénhatású vegyületek különböző hatással lehetnek a receptorokra

Ahogy korábban említettük, hígtrágya csak talajtani szakvéleményre alapozott talajvédelmi hatósági engedély birtokában juttatható ki mezőgazdasági területre, melyben az is meghatározásra kerül, hogy a területre milyen mennyiségű hígtrágya helyezhető el. A különböző típusú hígtrágyák nemcsak tápanyag összetételben, hanem EDC tartalomban is különböznek egymástól. A természetes hormon kiválasztódás és a hormonhatású készítmények felhasználása tekintetében fontos az állatállomány ivararányát és korcsoportját figyelembe venni. A jövőre nézve fontos, hogy toxikológiai vizsgálatokat végezzünk, és nagyobb hangsúlyt fektessünk a mezőgazdasági melléktermékek által kijuttatott hormonhatású anyagok mennyiségére és lehetséges hatásaira.

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Atractylenolide III is one of the major bioactive compounds in Atractylodes japonica rhizome; it has been used clinically for the treatment of gastrointestinal disorders. In the present study, a simple, rapid, and selective analytical method was developed and validated for the quantification of atractylenolide III in rat plasma samples using ultra-performance liquid chromatography–ion trap mass spectrometry (UPLC–ion trap MS). Liquid–liquid extraction with ethyl acetate was used for plasma sample preparation. Bergapten was used as an internal standard (IS). The separation of compounds was carried out on a C18 column, with isocratic elution of 0.1% formic acid in water–acetonitrile (45:55, v/v) at 35 °C. Mass detection was performed in the positive ion mode, under optimized conditions for an electrospray ionization source at m/z 249.1 for atractylenolide III and m/z 217.0 for the IS. The methods of instrumental analysis and plasma sample extraction were validated in terms of precision, accuracy, matrix effect, and extraction recovery, with acceptable values. The present method was successfully applied to the pharmacokinetic study of atractylenolide III in rat plasma samples after oral administration of A. japonica rhizome extract.

Open access
Phosphorus-induced zinc deficiency in maize (Zea mays L.) on a calcareous chernozem soil
Authors: Péter Csathó, Tamás Árendás, Anita Szabó, Renáta Sándor, Péter Ragályi, Klára Pokovai, Zoltán Tóth and Rita Kremper

Abstract

A long-term fertilizer experiment was set up on a calcareous chernozem soil with a wheat-maize-maize-wheat crop rotation, as part of the National Long-Term Fertilization Experiments (NLTFE) Network, set up with the same experimental pattern under different soil and agro-climatic conditions in Hungary. The effect of P fertilization on the soil, on maize yields, and on leaf P and Zn contents in the flowering stage were examined in the trials. In certain years, foliar zinc fertilizer was applied, in order to prove that yield losses due to P-induced Zn deficiency can be compensated by Zn application. Calcium-ammonium nitrate, superphosphate and 60% potassium chloride were used as NPK, and Zn-hexamine (in 1991) and Zn-sulphate (in 2006) as foliar Zn fertilizers.

In the years since 1970, averaged over 36 maize harvests, treatments N3P1K1 and N4P1K1, involving annual rates of 150 to 200 kg ha−1 N, 100 kg ha−1 K2O and 50 kg ha−1 P2O5, gave the highest yields (8.3 t ha−1 grain on average). As the years progressed, treatments exceeding 50 kg ha−1 P2O5 a year were found to have an increasingly unfavourable effect. Based on the yields of ten cycles (36 maize years), variants P2, P3 and P4 resulted in 16–30–45 t ha−1 grain yield losses in comparison to variant P1.

Investigations carried out in 1987, 1991 and 2006 showed that the leaf Zn content on plots with more than 150 to 200 mg kg−1 AL (ammonium lactate)-soluble P2O5 (over 30 mg kg−1 Olsen-P) dropped below 15 mg kg−1 and the P/Zn ratio rose to above 150 or even 250 in the flowering stage in two years. As a consequence of P-induced Zn deficiency, maize grain yields fell by 2 t ha−1 in two of the years investigated and by almost 5 t ha−1 in one year at the P4 level (200 kg ha−1 P2O5 year−1), in comparison to the P1 variant (50 kg ha−1 P2O5 year−1).

When 1.2 kg ha−1 foliar Zn was applied in the form of zinc hexamine, 1.7 to 1.8 t ha−1 maize grain yield surpluses were obtained on plots with higher P levels in 1991. In 2006 the P-induced Zn deficiency caused unexpectedly high (almost 5 t ha−1) grain yield losses on plots with higher P levels, so the maize grain yield surpluses obtained in response to 1.2 kg ha−1 foliar Zn application, in the form of zinc sulphate, were as high as 1.6 to 3.8 t ha−1.

The data clearly indicate that maize yields are impeded by both poor and excessive P status. Soil and plant analysis may be useful tools for monitoring the nutritional status of plants.

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Summary

The objective of this study was to develop a new rapid and robust high-performance thin-layer chromatographic (HPTLC) method for the estimation of rivaroxaban (RRB) in tablet dosage form using a quality by design approach. Chromatography was performed using a pre-coated silica gel aluminum plate 60 F254 (10 cm × 10 cm) as the stationary phase and toluene–methanol (7:3, V/V) as the mobile phase. Detection was carried out at 250 nm. The linear regression analysis data for the calibration plots showed r2 > 0.99 with a concentration range from 100–600 ng per band. A Box-Behnken experimental design with a response surface methodology was applied to study the effects of chamber saturation time, band length, and solvent front on the R F value and area of RRB. The R F value was predicted to be 0.63 ± 0.05 for RRB to optimize the chromatographic conditions based on the preliminary trials. The optimized HPTLC method was validated according to the International Conference on Harmonization (ICH) guideline Q2 (R1). The results of this study indicate that the quality by design (QbD) concept could be effectively applied to optimize a HPTLC method with a minimum number of experimental runs. The developed HPTLC method was successfully applied for routine analysis of RRB in tablet dosage form.

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A Rapid High-Performance Thin-Layer Chromatographic Method to Estimate Quercetin in Benincasa hispida (Thunb.) Cogn. Fruit Pulp
Authors: Anshul Shakya, Sushil Kumar Chaudhary, Hans Raj Bhat, Neelutpal Gogoi and Surajit Kumar Ghosh

Summary

Background: Ayurvedic medicines show great promise due to their holistic approach in the treatment of diseases. However, proper standardization is necessary for their integration into mainstream medicine. One such well-known Ayurvedic trailing herb is Benincasa hispida (Thunb.) Cogn. Its fruit contains numerous secondary metabolites, including quercetin, and is used to treat urinary calculi, blood disease, insanity, epilepsy, jaundice, dyspepsia, fever, and menstrual disorders. Objective: The current investigation was undertaken to develop and validate a rapid, sensitive, and reproducible method for quantifying quercetin in the hydroalcoholic extract of B. hispida fruit pulp (HABH). Materials and methods: The pre-coated thin-layer chromatography (TLC) aluminum plates with silica gel 60 F254 were used with solvent system comprising toluene-ethyl acetate-formic acid (5:4:0.2, V/V). Determination and quantification were performed by densitometric scanning using a deuterium lamp in the absorbance mode at 262 nm. The validation of precision, accuracy, and reproducibility of the developed high-performance thin-layer chromatographic (HPTLC) method were done as per the International Conference on Harmonization (ICH) guidelines. Results: The mobile phase used for the development of HPTLC/TLC plate yields a distinct band for quercetin (RF = 0.392). The limit of detection and limit of quantification for the method were found to be 20 and 60 ng per band, respectively. The quantified quercetin content was found to be 193.77 ± 2.86 µg in 10 mg of HABH, i.e., 1.94% w/w of HABH. Conclusion: This HPTLC method can be successfully employed for the standardization and quantitative analysis of quercetin in formulation containing B. hispida fruit pulp and it will be helpful in the quality control/assurance of such formulations.

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Summary

A thin-layer chromatography (TLC)–bioautography–mass spectrometry (MS) method coupled with a liquid chromatography–MS-controlled autopurification system was developed and applied for screening and isolating natural dipeptidyl peptidase IV (DPP IV) inhibitor from plant extracts. An unknown constituent with potential DPP IV inhibitory activity from bulbs of Fritillaria cirrhosa was discovered using TLC–bioautography, followed by using a TLC interface with mass spectrometry to obtain m/z of the target compound, and the purification of the compound was directly achieved with a mass-directed autopurification system for 40 runs of injection. Finally, 2.1 mg of the compound was obtained and identified as peimisine by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. The half maximal inhibitory concentration (IC50) of DPP IV inhibitory activity was determined at 80.5 µm comparing to 58.0 µm of the standard DPP IV inhibitor diprotin A by a spectrophotometric method.

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Rapid resolution liquid chromatography method for determination of malathion in pesticide formulation
Authors: L. Velkoska-Markovska and B. Petanovska-Ilievska

This paper presents a new, simple, precise, and accurate rapid resolution liquid chromatography (RRLC) method for determination of an active ingredient malathion in the pesticide formulation. The analysis was performed on a Poroshell EC 120-C18 (50 mm × 3 mm, 2.7 μm) analytical column using isocratic elution with a mobile phase consisted of acetonitrile–water (50:50, v/v), a flow rate of 1 mL/min, a constant column temperature at 25 °C, and ultraviolet-diode array detection (UV-DAD) at 220 nm. The specificity, selectivity, linearity, precision, and accuracy were tested for the method validation according to the Collaborative International Pesticides Analytical Council (CIPAC) and Directorate General Health and Consumer Protection (SANCO) guidelines and all tested parameters were found within acceptance criteria. The obtained results indicated that the proposed method can be used for routine analysis of the active ingredient malathion in the pesticide formulation “Etiol tecni” following the CIPAC and SANCO rules. The run time of analysis under the stipulated chromatographic conditions was about 2.5 min, meaning that the proposed method requires a small volume (< 1.5 mL) of the organic solvent (acetonitrile) making it cost-effective.

Open access
Secondary Metabolites in Arctium lappa L.: Variation Among Plant Parts and Phenological Stages
Authors: Nusrat Fayaz Bhatt, Raghbir Chand Gupta and Yogita Bansal

Summary

Arctium lappa L. (Asteraceae) occupies a prominent position in the ethnotherapeutics practices. The herb is known to contain a number of bioactive metabolites, which have immense therapeutic value. The objective of our present investigation was to estimate the variation of metabolites in different parts and phonological stages of A. lappa. This investigation has been done using a high-performance thin-layer chromatography technique. The present analysis reveals that the root (vegetative stages) holds the significantly high content of triterpenoids (betulinic acid, oleanolic acid, and lupeol), in comparison to the reproductive stage.

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Abstract

Various methods can be used for soil acidification monitoring, which can be useful towards remediation or preventing environmental degradation. It has been demonstrated that acidification can be made evident over the span of a few years, with proper monitoring. However, a reliance on pH as a main indicator can lead to detection inadequacies, especially where soils are relatively well buffered against acidity and acid deposition is negligible. A technique employing acid-neutralising capacity (ANC) derivation was applied to cultivated and uncultivated Alluvial Meadow soils to find out whether ANC data could prove effective in determining the occurrence and degree of acidification. Sampling and lab work were carried out between 2009 and 2010 on 33 sites under various land uses. Unlike pH, ANC, soil organic matter (SOM), and cation exchange capacity (CEC) decreased significantly. ANC analysis appears to be effective in detecting acidification trends over short periods and, in contrast to previous studies, under ostensibly unremarkable conditions.

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Simultaneous Densitometric Determination of Aspirin and Omeprazole by High-Performanee Thin-Layer Chromatography
Authors: Arun Maruti Kashid and Omkar Haribhau Kolhe

Summary

A new, simple, accurate, and precise high-performance thin-layer chromatographic (HPTLC) method has been developed for the separation and simultaneous estimation of aspirin and omeprazole. Standard and sample solutions of aspirin and omeprazole were applied to aluminum foil silica gel G 60 F254 HPTLC plates. The plates were developed with ethyl acetate-dichloromethane-glacial acetic acid 8:2:0.1 (V/V) as the solvent system. HPTLC detection was performed densitometrically at 241 nm. The linear range was 160–960 ng per band for aspirin and 80–480 ng per band for omeprazole, and the correlation coefficients (R 2) were 0.991 and 0.998, respectively. The limits of quantification (LOQ) were 31.89 and 8.01 ng per band, respectively, and the respective limits of detection (LOD) were 10.53 and 2.64 ng per band. Analysis of standard solutions revealed that precision and repeatability were good for both compounds studied.

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