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排序方式: 共有383条查询结果,搜索用时 31 毫秒
91.
D. T. Asilbekova 《Chemistry of Natural Compounds》2003,39(6):528-530
The composition of free and bound lipids from Capsicum annuum (Solanaceae) seeds was studied. Glycolipids, phospholipids, mono- and diacylglycerides, and free fatty acids were observed in the bound lipids. 相似文献
92.
Da-Le Guo Ling Qiu Dan Feng Xin He Xiao-Hua Li Zhi-Xing Cao 《Natural product research》2020,34(7):958-964
AbstractChemical epigenetic manipulation was applied to explore secondary metabolite of an endophytic fungus Penicillium herquei, which was obtained from the fruiting body of Cordyceps sinensis, and three previously undescribed polyketides with pyran-2-one scaffold were isolated from its fermentation broth containing 10?mg/L 5-aza-2-deoxycytidine (a frequently-used DNA methyltransferase inhibitor). The structures of these new compounds were identified by extensive spectroscopic analyses, and their absolute configurations were elucidated by quantum chemical ECD calculations. 相似文献
93.
A new sesquilignan from Selaginella sinensis (Desv.) Spring 总被引:1,自引:0,他引:1
Yan Zhi Wang Hui Chen Xiao Ke Zheng Wei Sheng Feng 《中国化学快报》2007,18(10):1224-1226
A new sesquilignan, namely sinensiol A, was isolated from the plant of Selaginella sinensis (Desv.) Spring. Its structure was identified on the basis of various spectroscopic data analysis. 相似文献
94.
M.K.-K. Figueiredo G.A. Romeiro R.N. Damasceno 《Journal of Analytical and Applied Pyrolysis》2009,86(1):53-57
The low temperature conversion (LTC) process applied to a castor seed sample at 380 °C produced pyrolysis oil (50%, w/w), pyrolytic char (29%, w/w), water (13%, w/w) and gas (8%, w/w) fractions. The oil fraction was subjected to analysis of by FTIR, 1H NMR, 13C NMR, GCMS and physical–chemical analysis such as sulfur content, distillation, density, flash-point, kinematic viscosity, Ramsbottom carbon residue, ash content, corrosivity to copper, water content and sediment, cold filter plugging point, and gross calorific value. 相似文献
95.
Summary TS-1 with relatively small crystal sizes (0.4-1.5 μm) was synthesized using inorganic sources of Ti and Si. The effects of
conditions in the preparation of seeds on the synthesized zeolites were studied. 相似文献
96.
Rita Celano Imma Pagano Sonia Carabetta Rosa Di Sanzo Luca Rastrelli 《Natural product research》2019,33(2):244-251
Consumers are aware of diet causing health problems and therefore there is an increased demand for natural ingredients that are expected to be safe and health-promoting. Many of these compounds belong to the class of flavonoids and can be divided into these five groups: flavanones, flavones, flavonols, flavanols, isoflavones and anthocyanidins. Extracts from citrus fruits are usually used as functional ingredients for several products. The aim of this paper was to develop an UHPLC-UV-ESI-HRMS method to define the metabolite profile of different parts of citrus fruit, of a particular cultivar called ‘Ovale Calabrese’, and in its main by-products. The high resolution mass spectrometry analysis allowed the identification of 27 compounds belonging to the classes of flavonoids and terpenoids. The high contents of phytochemical compounds, reveal the potential use of the ‘Ovale Calabrese’ as a rich source of nutraceutical compounds. 相似文献
97.
Fan-lin Wu Yong-hao Hu Peng Ji Chen-chen Li Jian He 《Biomedical chromatography : BMC》2022,36(6):e5362
98.
《Arabian Journal of Chemistry》2022,15(8):103985
This study aimed to investigate the effect of pumpkin (Cucurbita maxima) seed supplementation on the anthropometric measurements, biochemical parameters, and blood pressure (BP) of Indian women with metabolic syndrome (MetS). Initially, in vitro antioxidant activities of pumpkin seeds extract were assessed using standard methods. In vitro alpha-amylase, alpha-glucosidase, and dipeptidyl peptidase IV (DPP-IV) inhibition effects, along with glucose uptake assay using 3T3-L1 cell lines were performed to determine the antidiabetic effects of the seeds extract. Fatty acids and phytoconstituents were identified using gas chromatography-mass spectrometry (GC–MS). Indian women aged 30–50 years, having MetS were assigned either to intervention (n = 21) or control (n = 21) group on a random basis. Participants in the intervention group received 5 g of pumpkin seeds for 60 days. Participants in both intervention and control were advised to follow certain dietary guidelines throughout the study. Pumpkin seeds extract exhibited not only strong reducing power but also scavenged DPPH and ABTS●+ free radicals with low IC50 values. Pumpkin seeds inhibited alpha-amylase, alpha-glucosidase, and DPP-IV enzymes at varying concentrations with IC50 values of 138, 22, and 246 µg/mL, respectively. Furthermore, glucose uptake was enhanced by 213% at 300 ng/mL on the 3T3-L1 cell line. GC–MS analysis showed the presence of propyl piperidine, flavone, oleic acid, and methyl esters of fatty acids in the seed extract. On comparing the changes in mean reduction/ increment in the anthropometric measurements as well as biochemical parameters and BP between the groups, significant difference (P = 0.012) was observed only for fasting plasma glucose. Findings of the present study highlight the role of pumpkin seeds as a cost-effective adjunct in treating MetS. 相似文献
99.
Xinsheng Fang Jianhua Wang Xiaoliang Yu Guohui Zhang Jinpeng Zhao 《Journal of separation science》2010,33(8):1147-1155
An optimized microwave‐assisted extraction (MAE) method and an efficient HPLC analysis method were developed for fast extraction and simultaneous determination of oleanolic acid and ursolic acid in the fruit of Chaenomeles sinensis. The open vessel MAE process was optimized by using a central composite experimental design. The optimal conditions identified were microwave power 600 W, temperature 52°C, solvent to material ratio 32 mL/g and extraction time 7 min. The results showed that MAE is a more rapid extraction method with higher yield and lower solvent consumption. The HPLC–photodiode array detection analysis method was validated to have good linearity, precision, reproduction and accuracy. Compared with conventional extraction and analysis methods, MAE–HPLC–photodiode array detection is a faster, convenient and appropriate method for determination of oleanolic acid and ursolic acid in the fruits of C. sinensis. 相似文献
100.
Serge Kokot 《中国化学快报》2010,21(2):213-216
<正>High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets were combined into one matrix.The application of principal component analysis(PCA) for this data matrix showed that the samples were clustered into four groups in accordance with the plant sources and preparation procedures.Furthermore,partial least squares(PLS),back propagation artificial neural network(BP-ANN),and radial basis function artificial neural network(RBF-ANN) were effectively applied to predict the category of the four different samples in the test set. 相似文献