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排序方式: 共有583条查询结果,搜索用时 31 毫秒
571.
572.
Narisa Kamkaen Chuda Chittasupho Suwanna Vorarat Sarin Tadtong Watoo Phrompittayarat Siriporn Okonogi Pakakrong Kwankhao 《Molecules (Basel, Switzerland)》2022,27(10)
L-dopa, a dopaminergic agonist, is the gold standard for the treatment of Parkinson’s disease. However, due to the long-term toxicity and adverse effects of using L-dopa as the first-line therapy for Parkinson’s disease, a search for alternative medications is an important current challenge. Traditional Ayurvedic medicine has suggested the use of Mucuna pruriens Linn. (Fabaceae) as an anti-Parkinson’s agent. The present study aimed to quantify the amount of L-dopa in M. pruriens seed extract by HPLC analysis. The cytotoxicity and neuroprotective properties of M. pruriens aqueous extract were investigated by two in vitro models including the serum deprivation method and co-administration of hydrogen peroxide assay. The results showed the significant neuroprotective activities of M. pruriens seed extracts at a concentration of 10 ng/mL. In addition, the effects of L-dopa and M. pruriens seed extract on in vitro acetylcholinesterase activities were studied. M. pruriens seed extract demonstrated acetylcholinesterase inhibitory activity, while synthetic L-dopa enhanced the activity of the enzyme. It can be concluded that the administration of M. pruriens seed might be effective in protecting the brain against neurodegenerative disorders such as Parkinson’s and Alzheimer’s diseases. M. prurience seed extract containing L-dopa has shown less acetylcholinesterase activity stimulation compared with L-dopa, suggesting that the extract might have a superior benefit for use in the treatment of Parkinson’s disease. 相似文献
573.
Emad Karrar Isam A. Mohamed Ahmed Wei Wei Frederick Sarpong Charalampos Proestos Ryszard Amarowicz Emel Oz Aly Farag El Sheikha Ayman Y. Allam Fatih Oz Xingguo Wang 《Molecules (Basel, Switzerland)》2022,27(12)
In this study, the volatile compound profiles of gurum seed oil were determined using two methods: supercritical CO2 extraction (SFE) and the screw press process (SPP). For volatile compounds extraction and identification, headspace solid-phase micro-extraction (HS-SPME) and GC–MS were used, respectively. A total number of 56 volatile compounds were revealed and identified in oil extracted by SFE, while only 40 compounds were detected in extracted oil by SPP. Acids, aldehydes, esters, ketones, furans, and other components were present in the highest ratio in oil extracted by SFE. In contrast, alcohols and alkenes were found in the highest proportion in oil extracted by SPP. In this study, it was observed that SFE showed an increase in the amounts of volatile compounds and favorably impacted the aroma of gurum seed oil. The results reveal that different extraction methods significantly impact the volatile components of gurum seed oil, and this study can help evaluate the quality of the oil extracted from gurum seeds. 相似文献
574.
Yi-Fen Chiang Cheng-Pei Chung Jing-Hui Lin Wenchang Chiang Hsin-Yuan Chen Mohamed Ali Yin-Hwa Shih Kai-Lee Wang Tsui-Chin Huang Hsin-Yi Chang Li-Chun Lin Tzong-Ming Shieh Shih-Min Hsia 《Molecules (Basel, Switzerland)》2022,27(13)
The antitumor effects of Coix lacryma-jobi L. var. ma-yuen Stapf. (adlay seed) ethanolic extract have been increasingly shown. This study aimed to investigate the beneficial effects of both the fractions and subfractions of adlay seed ethanolic extract on the human breast (MCF-7) and cervical (HeLa) cancer cell lines, as well as exploring their possible mechanisms of action. The ethanolic extracts were obtained from different parts of adlay seed, including AHE (adlay hull extract), ATE (adlay testa extract), ABE (adlay bran extract) and PAE (polished adlay extract). The results of a 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl- tetrazolium bromide (MTT) assay showed that AHE-Ea and ATE-Ea showed significant growth inhibitory effects in a dose-dependent manner. The results also showed that the AHE-Ea-K, AHE-Ea-L, ATE-Ea-E and ATE-Ea-F subfractions inhibited cell proliferation, induced cell cycle arrest in the G0/G1 phase and decreased CDK4/Cyclin D1 protein expression. Finally, the extract activated caspase-3 activity and PARP protein expression, which induced MCF-7 and HeLa cell apoptosis. We then used liquid chromatography–mass spectrometry (LC/MS) to identify the potential active components., Quercetin showed an anticancer capacity. In conclusion, the AHE-Ea-K, AHE-Ea-L, ATE-Ea-E and ATE-Ea-F subfractions showed antitumor effects through the inhibition of MCF-7 and HeLa cell line viability, as well as inducing apoptosis and cell cycle arrest. 相似文献
575.
反相高效液相色谱法测定白肋烟烟叶中的游离氨基酸 总被引:1,自引:0,他引:1
建立了一种用于烟草中游离氨基酸测定的反相高效液相色谱法.实验采用超声波水解、邻苯二甲醛/3-巯基丙酸作为衍生剂进行柱前衍生.色谱柱为依利特C18柱(4.6mmi.d.×250mm,5μm),流动相A为18mmol/L的醋酸钠溶液(pH7.2)含体积分数为0.002%的三乙胺和0.3%的四氢呋喃,流动相B组成为:100mmol/L的醋酸钠溶液(pH7.2)-乙腈-甲醇(体积比为1:2:2),流速为1.0mL/min,柱温为40℃.荧光检测器,激发波长350nm,发射波长450nm.方法的回收率为95.3%~100.7%,RSD为2.32%~9.24%(n=6).该方法简便、准确、重现性好.测定了不同肥料配比生产的白肋烟烟叶中17种游离氨基酸的含量.结果表明,不论有机肥与无机肥怎样配比,天冬氨酸的含量与各氨基酸相比都是最高的;随着饼肥的加入,大部分氨基酸的含量是先增加后逐渐降低的趋势,15%饼肥+85%无机肥与30%饼肥+70%无机肥配比时,大部分游离氨基酸的含量接近,30%饼肥+70%无机肥配比时的游离氨基酸总量最高,综合考虑,30%饼肥+70%无机肥配比时的烟叶质量最好. 相似文献
576.
采用改进后的顶部籽晶熔渗生长(RE+011 TSIG)工艺,通过在固相先驱粉中掺杂不同含量的MgO来有效地提高NdBCO籽晶的熔化温度,从而成功地制备出直径为32 mm的大尺寸单畴SmBCO超导块材.结果表明,MgO的掺杂对NdBCO超导块材的熔化温度有着明显的提高,随着固相先驱粉中MgO掺杂量的增加,Mg2+离子逐渐进入到Nd123相的晶格中,当掺杂量达到16 wt%时呈现出饱和状态,且NdBCO超导块材的熔化温度提高近18℃,可有效地抑制在制备SmBCO超导块材的过程中出现的NdBCO籽晶熔化现象. 相似文献
577.
为对糯玉米种子热损伤粒进行无损快速鉴别并探索热损伤过程对糯玉米种子的影响,以糯玉米种子"京科糯2000"为例,用Videometer近紫外-可见-短波近红外多光谱成像仪分别以胚面向上和胚面向下方式采集糯玉米种子对照组及热损伤组多光谱成像数据,分别提取胚面向上胚部、胚面向上胚乳部、胚面向下胚乳部单点多光谱数据,并对胚面向上胚部和胚面向上胚乳部多光谱数据做初级融合;对多光谱数据进行基线校正预处理后计算各光谱数据样本标准差,进而通过光谱数据样本标准差的变化分析热损伤对糯玉米种子各部位的影响;基于多光谱数据采用偏最小二乘-判别分析算法建立糯玉米种子热损伤粒无损鉴别模型,对所建模型进行全交互验证,并与近红外光谱数据模型比较。结果表明,热损伤对糯玉米种子胚、胚乳有不同的影响,多光谱数据和近红外光谱数据表现出一致的变化趋势。采用多光谱数据建立热损伤粒鉴别模型,各模型前3主成分得分3D散点图中,对照组和热损伤组样品表现出一定的分离趋势,校正数据正确率在96%~100%之间,交互验证数据正确率在92%~100%之间,其中,糯玉米种子胚面向上胚部光谱和胚乳部光谱初级融合数据建模效果最好,校正数据正确率10... 相似文献
578.
Cactus is a tropical fruit with a high nutritional value; however, little information is available regarding the comprehensive utilization of its byproducts. This study aimed to explore the composition and nutritional value of cactus fruit seed oil (CFO) and reveal the effects of ultrasound-assisted extraction and traditional solvent extraction on oil quality. Foodomics analysis showed that CFO extracted using a traditional solvent is rich in linolenic acid (9c12cC18:2, 57.46 ± 0.84 %), α-tocopherol (20.01 ± 1.86 mg/100 g oil), and canolol (200.10 ± 1.21 μg/g). Compared to traditional solvent extraction, ultrasound-assisted extraction can significantly increase the content of lipid concomitants in CFO, whereas excessive ultrasound intensity may lead to the oxidation of oils and the formation of free radicals. Analysis of the thermal properties showed that ultrasound had no effect on the crystallization or melting behavior of CFO. To further demonstrate the nutritional value of CFO, a lipopolysaccharide (LPS)-induced lipid metabolism imbalance model was used. Lipidomics analysis showed that CFO significantly reduced the content of oxidized phospholipids stimulated by LPS and increased the content of highly bioactive metabolites such as ceramides, thus alleviating LPS-induced damage in C. elegans. Hence, CFO is a functional oil with high value, and ultrasound-assisted extraction is advocated. These findings provide new insights into the comprehensive utilization of cactus fruits. 相似文献
579.
《印度化学会志》2023,100(9):101072
The most crucial and demanding universal issue lies in the enrichment of sustainable drive technology. As traditional resource, petrochemical becomes increasingly scarce in the future; mankind must turn to renewable alternatives to yield liquefied fuels and valuable commodities through sustainable process. It has been reported that furan compounds serve as an excellent platform molecule derived from defatted rice bran. The current work aims at the synthesis of copper ferrite nano catalyst by microwave assisted solution incineration approach. The catalytic properties stood verified by X-ray diffraction, SEM, EDAX and BET techniques. The catalytic performance of the copper ferrite catalyst were reinforced through in-situ microwave assisted acetalization reaction of furfural with discrete solvents like methanol, ethanol, and 1-propanol at optimum reaction conditions for the preparation of wide range of commodity chemicals such as carboxylic acids, alkyl esters, di alkyl acetals, di ketones which are of commercial importance. The comparative study of relative yield of the products with different solvents is reported. The formation of the value-added products were confirmed by GC-MS, FT-IR technique. The catalysts from the reaction mixture are recovered by magnetic field. 相似文献
580.