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621.
The analgetic activity of Carica papaya leaves (CPL) extracts (n-hexane, ethyl acetate, ethanol) was investigated in mice model using acetic acid induced pain (Siegmund method). Experimental animals were divided into 11 groups and received n-hexane, ethyl acetate, and ethanol extracts at doses of 0.175, 0.35, 0.70 mg/kg bw orally; CMC-Na 0.5% (control group); 50 mg/ kg bw of aspirin. The results showed that all extracts at the doses of 0.175, 0.35 and 0.70 mg/kg bw gave significant analgetic activity (p<0.05) compared to control group. Ethanol extract of CPL dose of 0.70 mg/kg bw showed the best analgetic activity that was comparable to aspirin. 相似文献
622.
Jisheng Li Qiqi Wang Yao Wang Mencuo La Ruisha Mian Liangliang He Ji Suonan Denglang Zou 《Journal of separation science》2023,46(19):2300320
This study presents an efficient strategy for large-scale preparation of low polarity gingerols directly from ginger crude extract by high-speed countercurrent chromatography with different rotation mode. The ultrasonic-assisted extraction conditions were optimized by response surface methodology and the results showed the major low polarity gingerols could be well enriched under the optimized extraction conditions. Then the crude extract without any pretreatment was directly separated by high-speed countercurrent chromatography with different rotation mode using n-hexane/ethyl acetate/methanol/water (6:4:6:4, v/v/v/v) as the solvent system. In about 400 min, five major gingerols including 150 mg of [6]-gingerol, 50 mg of [8]-gingerol, 20 mg of [6]-shogaol, 43 mg of [6]-dehydrogingerdione, and 40 mg of [10]-gingerol were obtained from 1.2 g of crude extract in a single run with repeated injection. Their structures were identified by 1H-NMR spectroscopy. 相似文献
623.
《Arabian Journal of Chemistry》2023,16(6):104719
This study was carried out to investigate the antimicrobial activity of methanolic flower extract of Plumeria alba and identification of the possible antimicrobial compounds through GC–MS analysis. Antimicrobial efficacy of the methanolic extract of 5 ppm to 1000 ppm concentrations was assessed against five fungal (Trichoderma viride, T. reesei, T. harzianum, T. hamatum and T. koningii) and five bacterial species (Escherichia coli, Salmonella sp., Pseudomonas sp., Bacillus sp. and Staphylococcus sp.). In general, all the concentrations of the extract significantly reduced growth of all the fungal and bacterial species. However, there was a significant variation in susceptibility of different fungal and bacterial species to the applied concentrations of the extract. The extract was the most effective against T. reesii followed by T. viride, T. harzianum, T. hamatum and T. koningii causing 11–97%, 36–90%, 24–86%, 7–77% and 9–76% reduction in their growth. Similarly, there was 23–93%, 12–92%, 36–90%, 19–90% and 8–84% reduction in growth of Bacillus sp., Staphylococcus sp., E. coli, Pseudomonas sp., and Salmonella sp., respectively, due to different concentrations of methanolic extract. GC–MS analysis of the extract showed the presence of 21 constituents. The most abundant compound was benzofuran, 2,3-dihydro- (27.95%). Other important compounds included cyclononanone (14.59%), 9-octadecyne (14.29%), 9,12,15-octadecatrienoic acid, methyl ester, (Z,Z,Z)- (10.28%), benzyl alcohol (5.57%), 1-decanol, 2-hexyl- (5.44%), 2,6-octadien-1-ol, 3,7-dimethyl-, acetate, (Z)- (3.76%), 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- (2.48%) and heptadecane (2.43%). It is concluded that methanolic extract of P. alba flowers has the potential to control both fungal as well as bacterial growth. 相似文献
624.
Duarte LC Carvalheiro F Lopes S Neves I Gírio FM 《Applied biochemistry and biotechnology》2008,148(1-3):119-129
Yeast single-cell protein and yeast extract, in particular, are two products which have many feed, food, pharmaceutical, and
biotechnological applications. However, many of these applications are limited by their market price. Specifically, the yeast
extract requirements for culture media are one of the major technical hurdles to be overcome for the development of low-cost
fermentation routes for several top value chemicals in a biorefinery framework. A potential biotechnical solution is the production
of yeast biomass from the hemicellulosic fraction stream. The growth of three pentose-assimilating yeast cell factories, Debaryomyces hansenii, Kluyveromyces marxianus, and Pichia stipitis was compared using non-detoxified brewery’s spent grains hemicellulosic hydrolyzate supplemented with mineral nutrients.
The yeasts exhibited different specific growth rates, biomass productivities, and yields being D. hansenii as the yeast species that presented the best performance, assimilating all sugars and noteworthy consuming most of the hydrolyzate
inhibitors. Under optimized conditions, D. hansenii displayed a maximum specific growth rate, biomass yield, and productivity of 0.34 h−1, 0.61 g g−1, and 0.56 g l−1 h−1, respectively. The nutritional profile of D. hansenii was thoroughly evaluated, and it compares favorably to others reported in literature. It contains considerable amounts of
some essential amino acids and a high ratio of unsaturated over saturated fatty acids. 相似文献
625.
Qiang Wang Zhang Rong Jie Teng Yoshihisa Takaishi Hong Quan Duan 《中国化学快报》2008,19(2):187-189
Two new diterpenes, 15-ethyl-18-methyl pinifolate (1) and 18-hydroxy-labda-8(17), 13E-dien-15-acetate (2), were isolated from the needles of Pinus sylvestris. Their structures were elucidated by spectroscopic methods, including 2D-NMR spectra. Compound 1 exhibited the significant cytotoxic activity against the human carcinoma cell lines Hela, SK-N-SH and BEL-7402 in vitro. 相似文献
626.
We elucidated the structure and metabolite profile of eleutheroside B, a component derived from the extract of Acanthopanax senticosus Harms, after oral administration of the extract in rats. Samples of rat plasma were collected and analyzed by selective high‐resolution liquid chromatography/quadrupole time‐of‐flight mass spectrometry (UPLC/Q‐TOF MS) automated data analysis method. A total of 11 metabolites were detected: four were identified, and three of those four are reported for the first time here. The three new plasma metabolites were identified on the basis of mass fragmentation patterns and literature reports. The major in vivo metabolic processes associated with eleutheroside B in A. senticosus include demethylation, acetylation, oxidation and glucuronidation after deglycosylation. A fairly comprehensive metabolic pathway was proposed for eleutheroside B. Our results provide a meaningful basis for drug discovery, design and clinical applications related to A. senticosus in traditional Chinese medicine. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
627.
针对核主元分析在人脸识别中的时间开销过大的不足,提出了一种核主元分析的DSP实现方法.介绍了核主元分析算法原理,给出了DSP平台的硬件框架和程序优化方案.在DSP硬件平台上的测试结果表明:系统运行稳定,与通用计算机平台相比,明显提高了识别速度,同时保证了人脸识别率,具有一定的实用价值. 相似文献
628.
The biological synthesis of gold nanoparticles (AuNPs) of various shapes (triangle, hexagonal, and spherical) using hot water olive leaf extracts as reducing agent is reported. The size and the shape of Au nanoparticles are modulated by varying the ratio of metal salt and extract in the reaction medium. Only 20 min were required for the conversion into gold nanoparticles at room temperature, suggesting a reaction rate higher or comparable to those of nanoparticles synthesis by chemical methods. The variation of the pH of the reaction medium gives AuNPs nanoparticles of different shapes. The nanoparticles obtained are characterized by UV–Vis spectroscopy, photoluminescence, transmission electron microscopy (TEM), X-ray diffraction (XRD), FTIR spectroscopy and thermogravimetric analysis. The TEM images showed that a mixture of shapes (triangular, hexagonal and spherical) structures was formed at lower leaf broth concentration and high pH, while smaller spherical shapes were obtained at higher leaf broth concentration and low pH. 相似文献
629.
630.
采用SPE柱净化、高效液相反相离子对色谱分离、紫外检测器(HPLC/UV)测定乳制品及其原料中的硫氰酸盐。试样经乙酸沉淀蛋白、Oasis WAX SPE柱净化和浓缩,以甲醇和磷酸盐缓冲液加离子对试剂为流动相,经Symmetry C18色谱柱分离,在231 nm波长处进行检测,外标法定量。结果表明,硫氰酸盐浓度在0.2~50 mg/L范围内线性良好,相关系数大于0.999,方法检出限为0.05 mg/kg,定量下限为0.15 mg/kg,在加标量为1、5、25 mg/kg时的回收率为77%~104%。该方法重现性好、检测时间短,灵敏度高,为乳制品及其原料中硫氰酸盐的定量检测提供了较为理想的方法。 相似文献