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161.
Ajoy Saha Narendra A. Gajbhiye Biraj B. Basak Ponnuchamy Manivel 《International journal of environmental analytical chemistry》2018,98(7):622-643
Since the discovery of aflatoxins (AFs) in the 1960s, much research has focused on detecting the toxins in contaminated food and feedstuffs. But the quality determination in medicinal plant matrices with respect to AFs is scare. Hence, a simple, accurate and sensitive high-performance liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) method was developed for simultaneous determination of AFs AFB1, AFB2, AFG1 and AFG2 in two Indian popular medicinal herbs i.e. senna (Cassia angustifolia) and kalmegh (Andrographis paniculata). AFs have been extracted from herb matrix using a QuEChERS (quick, easy, cheap, effective, rugged and safe)-based extraction procedure followed by applying primary secondary amine and C18 for further clean-up step and then were quantified under the multiple reaction monitoring together with positive ionisation modes. Matrix-matched calibration was used for quantification in order to reduce the matrix effect. Validation of the method was carried out in herbs by recovery experiments. Recoveries of the spiked samples were in the range of 61.9–111.5% with an inter-day and intraday relative standard deviation lower than 20.0%. Limits of detection and quantification ranged from 0.41 to 0.95 ng mL?1 and 1.2 to 3.8 μg kg?1, respectively. The expanded uncertainty of the method was <21% for all the toxins in both the herbs. Finally, the proposed method was successfully applied to determine AF residues in real field samples of senna and kalmegh obtained from different locations in India. 相似文献
162.
An MEKC method was developed for the determination of the five pharmaceutically important anthraquinones: chrysophanol (1), physcion (2), emodin (3), aloe-emodinin (4), and rhein (5) in Cassia obtusifolia (Leguminosae). A buffer solution (pH 9.00) composed of 20 mM sodium borate, 20 mM sodium deoxycholate (DOC), and 15% ACN was found to be the most suitable electrolyte for this separation. Regression equations revealed linear relationships (correlation coefficients: 0.9993, 0.9992, 0.9996, 0.9989, and 0.9991) between the peak area of each compound (1, 2, 3, 4, and 5) and its concentration. The RSDs of migration times and peak areas were <1.23 and 2.72% within 1 day, respectively. The effects of pH value, surfactant (DOC) concentration, and organic modifier on the migration were also studied. By this way, the contents of five anthraquinones in the extracts of the seed of C. obtusifolia (Leguminosae) from different sources were successfully determined within 14 min. 相似文献
163.
Tomato and pomegranate seeds were analyzed quantitatively. Lignin hydrochloride was isolated from their seeds and characterized. Lignocarbohydrate complexes were isolated by base hydrolysis. Their elemental composition, IR spectra, and molecular weights were determined. 相似文献
164.
ZhongJunMA IsaoFUJII YutakaEBIZUKA XianLI 《中国化学快报》2004,15(1):58-60
Two novel compounds, named sphaerophyside SC and SD were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula. The structures of the compounds were elucidated on the basis of the NMR data, especially the 2D NMR technique. 相似文献
165.
Winkler Elisabeth Foidl Nikolaus Gübitz Georg M. Staubmann Ruth Steiner Walter 《Applied biochemistry and biotechnology》1997,(1):449-456
Jatropha curcas is a tropical plant widely distributed in arid areas. The seeds contain about 55% of oil, which is mainly used for the production
of soap as a fuel and after transesterification as biodiesel. Various methods for recovering of oil from the seeds, including
extraction with organic solvents and water, have been investigated. Compared to hexane extraction (98%) the oil extraction
using water only yielded 38% of the total oil content of the seeds. Using several cell wall degrading enzymes during aqueous
extraction a maximum yield of 86% was obtained. The influence of cellulolytic, hemicellulolytic enzymes, as well as proteases
was studied. The experiments were carried out at different pH-values and temperatures to find out the optimum for oil recovering
using enzymes. , Surprisingly, the best results (86%) were obtained using an alkaline protease. Combinations of proteases
with hemicellulases and/or cellulases did not further increase the extraction yield. The enzyme-supported aqueous extraction
offers a nontoxic alternative to common extraction methods using organic solvents with reasonable yields. 相似文献
166.
Mohamed Bouhrim Hayat Ouassou Salima Boutahiri Nour Elhouda Daoudi Hamza Mechchate Bernard Gressier Bruno Eto Hamada Imtara Amal A. Alotaibi Mohammed Al-zharani Abderrahim Ziyyat Hassane Mekhfi Abdelkhaleq Legssyer Mohammed Aziz Mohamed Bnouham 《Molecules (Basel, Switzerland)》2021,26(6)
Opuntia dillenii Ker Gawl. is one of the medicinal plants used for the prevention and treatment of diabetes mellitus (DM) in Morocco. This study aims to investigate the antihyperglycemic effect of Opuntia dillenii seed oil (ODSO), its mechanism of action, and any hypoglycemic risk and toxic effects. The antihyperglycemic effect was assessed using the OGTT test in normal and streptozotocin (STZ)-diabetic rats. The mechanisms of action were explored by studying the effect of ODSO on the intestinal absorption of d-glucose using the intestinal in situ single-pass perfusion technique. An Ussing chamber was used to explore the effects of ODSO on intestinal sodium-glucose cotransporter 1 (SGLT1). Additionally, ODSO’s effect on carbohydrate degrading enzymes, pancreatic α-amylase, and intestinal α-glucosidase was evaluated in vitro and in vivo using STZ-diabetic rats. The acute toxicity test on mice was performed, along with a single-dose hypoglycemic effect test. The results showed that ODSO significantly attenuated the postprandial hyperglycemia in normal and STZ-diabetic rats. Indeed, ODSO significantly decreased the intestinal d-glucose absorption in situ. The ex vivo test (Ussing chamber) showed that the ODSO significantly blocks the SGLT1 (IC50 = 60.24 µg/mL). Moreover, ODSO indu\ced a significant inhibition of intestinal α-glucosidase (IC50 = 278 ± 0.01 µg/mL) and pancreatic α-amylase (IC50 = 0.81 ± 0.09 mg/mL) in vitro. A significant decrease of postprandial hyperglycemia was observed in sucrose/starch-loaded normal and STZ-diabetic ODSO-treated rats. On the other hand, ODSO had no risk of hypoglycemia on the basal glucose levels in normal rats. Therefore, no toxic effect was observed in ODSO-treated mice up to 7 mL/kg. The results of this study suggest that ODSO could be suitable as an antidiabetic functional food. 相似文献
167.
STUDIES ON THE IMBIBITIONAL CHILLING INJURY AND THE REPARATION OF DAMAGED MEMBRANE SYSTEMS IN SOYBEAN SEEDS 总被引:1,自引:0,他引:1
Two soybean (Glycine max Merrill.) cultivars, Jilin No. 3 and Heihe No. 3 which are sensitive to imbibitional chilling injury were used to investigate the difference between the damaged seeds and control in a series of items, including the leakage of soaking solution (K~+, Na~+, Ca~(++), Mg~(++), Fe~(++) and Zn~(++) various mineral elements, phosphorus, sugars, proteins and more than 10 amino acids, etc.), ATPase activity, the morphological character of the cell wall and the development of organelles. Comparisons between the PEG priming and the chilling injury seeds were also conducted for confirmation.This paper deals with the above experimental results and some mechanisms about the imbibitional chilling injury in seeds are also discussed. The authors stress that investigation of the mechanism of imbibitional chilling injury must be conducted from the points of the reparation in a broad sense, not only limited to the membrane itself, but also including the physical membrane reparation as well as recove 相似文献
168.
A. Zielenkiewicz 《Journal of Thermal Analysis and Calorimetry》1995,45(4):811-821
The results of calorimetric studies of 5SrRNA solutions isolated from lupin seeds in the pressence of the ClO 4 ? , NO 3 ? , Br 4 ? , SO 4 2? , Cl?, COO? (maleic and fumaric acids) anions were reported. The plots of calorimetric curves, enthalpy of conformational changes of two state transitions were presented. Using the deconvolution method proposed by Freire and Biltonen the elementary transitions were distinguished and discussed. 相似文献
169.
Bao-jun Shi Wei-dong Zhang Hong-fang Jiang Yu-yao Zhu Lei Chen Xiao-ming Zha 《Natural product research》2016,30(1):35-41
Seeds of Cassia obtusifolia L. are known as homology of medicine and food material, which is a commonly consumed beverage in China. One new compound, 8-hydroxy-1,7-dimethoxy-3-methylanthracene-9,10-dione-2-O-β-d-glucoside (1), together with 11 known compounds, including seven anthraquinones (2–8), was isolated from the seeds. The 2D NMR data of compound 2 are reported for the first time. The structures of the compounds were established on the basis of 1D and 2D NMR, IR and HR-ESI-MS spectra. The cytotoxic activities of all the compounds against five cell lines (LO2, HCT-116, A549, HepG2 and SGC7901) were evaluated by using CCK8 methods. Compounds 1, 3 and 7 show moderate cytotoxicity towards HCT-116 cells compared with oxaliplatin. 相似文献
170.