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51.
Sesame seed is a rich source of dietary lignans 总被引:6,自引:0,他引:6
The variation in the contents of sesamin and sesamolin was studied in oils extracted from 65 samples of sesame seeds (Sesamum indicum L.) from plants with shattering (n=29), semishattering (n=7), and nondehiscent (n=29) capsules. The oil content ranged from 32.5 to 50.6% and was greater in white than black seeds (P<0.001). The sesamin and sesamolin contents in seeds ranged from 7 to 712 mg/100 g (mean±SD, 163±141 mg/100 g) and from 21
to 297 mg/100 g (101±58 mg/100 g), respectively, with no difference between black and white seeds. Thus, there was a wide
variation in the contents of sesamin and sesamolin, which were positively correlated (R
2=0.66, P<0.001). There were negative correlations between the contents of sesamin and the contents of sesaminol (R
2=0.37) and sesamolinol (R
2=0.36) and between the content of sesamolin and those of sesaminol (R
2=0.35) and sesamolinol (R
2=0.46) (P<0.001). Sesame seeds had an average of 0.63% lignans, making them a rich source of dietary lignans. 相似文献
52.
X Yao E Shang G Zhou Y Tang S Guo S Su C Jin D Qian Y Qin JA Duan 《International journal of molecular sciences》2012,13(8):10305-10315
The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years) are ignored and become obsolete after fruit harvest season (November). In this paper, we expand the tree age range (from one to 300 years) and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars. 相似文献
53.
H Yao X Du L Yang W Wang F Yang C Zhao X Meng L Zhang Y Zu 《International journal of molecular sciences》2012,13(7):8775-8788
The Brönsted acidic ionic-liquid [HO3S(CH2)4mim] HSO4, a novel dual catalyst–solvent, has been successfully applied in simultaneous microwave-assisted extraction and hydrolysis for the determination of flavonol glycosides in Ginkgo foliage. The parameters, namely the [HO3S(CH2)4mim]HSO4 concentration, microwave-irradiation power, microwave-irradiation time, and solid–liquid ratio, were optimized. The optimum conditions were: an amount of 1.5 M [HO3S(CH2)4mim]HSO4, a microwave-irradiation power of 120 W, an irradiation time of 15 min, and a solid–liquid ratio of 1:30 g/mL. Compared with traditional methods the proposed approach demonstrates higher efficiency in a shorter operating time, and is an efficient, rapid, and simple sample preparation method. 相似文献
54.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(2):345-355
Deoxynivalenol, T-2 and HT-2 toxins are mycotoxins frequently occurring in cereals and cereal-based products along with their conjugated forms. In this paper, we provide insights into the fate of deoxynivalenol, T-2 and HT-2 toxins and their glucoside derivatives during bread making, using naturally contaminated wheat flour. High-resolution mass spectrometry was used to assess the extent of degradation of the three mycotoxins during bread baking and to identify some glucoside conjugates, namely deoxynivalenol, T-2 and HT-2 mono-glucosides, detected both in the flour and in the respective breads. Our findings show deoxynivalenol's levels markedly increased upon baking, whereas those of HT-2 and T-2 toxins were decreased in the final bread with special regard to the T-2 toxin. 相似文献
55.
BACKGROUND: The application of tea seed extract (TSE) has been widely investigated owing to its biological activities. In this paper, two flavonol triglycosides found in TSE, camelliaside A (CamA) and camelliaside B (CamB), were subjected to hydrolysis in the presence of three commercial enzyme complexes of the Pectinex® series, 5XL, XXL and Ultra SP‐L (Ultra). RESULTS: XXL and 5XL induced stepwise deglycosylation of CamA and CamB to yield kaempferol diglycoside (nicotiflorin), kaempferol monoglycoside (astragalin) and kaempferol, while Ultra produced an additional new compound (1) that had not been observed in earlier studies. Upon hydrolysis of isolated CamA and CamB, compound (1) was obtained only from CamB. Both the molecular ion peak in liquid chromatography/mass spectrometry and the 1H and 13C nuclear magnetic resonance spectra of (1) isolated by Ultra‐induced hydrolysis of TSE indicated that (1) was kaempferol 3‐O‐β‐xylopyranosyl (1 → 2)‐β‐glucopyranoside (leucoside), formed by selective hydrolysis of the rhamnosyl moiety of CamB. CONCLUSION: Pure leucoside can be prepared by enzymatic partial hydrolysis of TSE. This is the first study to address the synthesis of pure leucoside from a natural source. Copyright © 2012 Society of Chemical Industry 相似文献
56.
绿茶茶汤中黄酮醇及其苷类的测定方法以及对茶汤色度的影响 总被引:7,自引:0,他引:7
黄酮醇及其苷类物质是构成绿茶汤色的重要组分。绿茶中含有20多种黄酮醇及其苷类物质,其中以槲皮素、杨梅素、山柰素的3种苷类物质为主。文中采用高效液相色谱法研究了绿茶茶汤酸水解前后槲皮素、杨梅素、山柰素的含量变化,建立了黄酮醇及其苷类含量的检测方法。利用正交实验方法得到茶汤水解的优化条件为:5 mL的茶汤中加15 mL纯甲醇、5 mL 6 mol/L HCl,在75℃下水解时间2h,芦丁的平均水解率为82.74%。对不同贮藏期间茶汤色度与黄酮醇及其苷类的相关性进行了研究,结果表明:茶汤贮藏过程中随着茶汤的红绿度(a)和黄蓝度(b)不断升高,杨梅素苷含量逐步下降,杨梅素苷与茶汤的红绿度、黄蓝度的相关系数分别为:-0.982 1、-0.882 6,但与茶汤明亮度(L)的相关性不显著。槲皮素和山柰素及其苷类与茶汤色泽变化关系不密切。 相似文献
57.
Carmen Goyoaga Carmen Burbano Carmen Cuadrado Alejandro Varela Eva Guillamón Mercedes M. Pedrosa Mercedes Muzquiz 《European Food Research and Technology》2008,227(5):1537-1542
This work examined the content and distribution of the pyrimidine glucosides vicine and convicine, and the nonproteic amino
acid l-DOPA in cotyledons and embryo axes along the germination and seedling growth of Vicia faba L. vars. Alameda and Brocal. The behaviour of these compounds was similar in both varieties. Vicine and convicine, implicated
in favism disease, slowly declined in cotyledons. In embryo axis, vicine levels were sharply reduced and convicine amount
was slightly increased as assay progressed. Total pyrimidine glucosides remained unchanged in the whole plant during the study.
l-DOPA only appeared in the embryo axis of V. faba seeds and the highest content was observed in Brocal variety at 6 DAI (days after imbibition). The information provided in
this study could be valuable for a possible role of embryo axis, rich in l-DOPA, for the treatment of Parkinson’s disease and also as a choice ingredient for functional foods or as nutraceutical. 相似文献
58.
59.
Qualitative analysis of the ethyl acetate extracts from three bayberry cultivars, Xiangshan, Biqi and Dongkui, was performed by means of a hyphenated technique of HPLC coupled to photodiode array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESIMS). Three phenolic compounds were identified (gallic acid, protocatechuic acid, and quercetin 3-glucoside) and seven others (two myricetin hexoside and two myricetin deoxyhexoside derivatives; quercetin hexoside and quercetin deoxyhexoside derivatives; kaempferol hexoside derivative) partially identified. Quantification of phenolic compounds was performed by HPLC-DAD, which revealed that gallic acid (2.6–7.0 mg/kg FW) was the major phenolic acid in all analysed cultivars. Myricetin glycosides (71.1 mg/kg FW) were the major flavonol glycosides in cultivar Xiangshan and quercetin glycosides (117.8 mg/kg FW) were the major ones in cultivar Biqi. Cultivar Dongkui had medium contents of quercetin glycosides (48.0 mg/kg FW) and myricetin glycosides (53.2 mg/kg FW). Kaempferol glyosides (3.1–4.6 mg/kg FW) were the lowest contents of flavonol glycosides in the assayed bayberries. These results are relevant not only from a nutritional point of view, but also in the control of color stability and haze formation during bayberry juice processing and storage. 相似文献
60.
J. Hemavathy 《Journal of the American Oil Chemists' Society》1991,68(9):651-652
Total seed lipids extracted fromMurraya koenigii (Linn), Rutaceae amounted to 4.4% of the dry seed. The total lipids consisted of 85.4% neutral lipids, 5.1% glycolipids and
9.5% phospholipids. Neutral lipids consisted of 73.9% triacylglycerols, 10.2% free fatty acids and small amounts of diacylglycerols,
monoacylglycerols and sterols. At least five glycolipids and seven phospholipids were identified. Sterylglucoside and acylated
sterylglucoside were major glycolipids, while digalactosyldiacylglycerol, monogalac-tosyldiacylglycerol and monogalactosylmonoacylglycerol
were present in small quantities. The phospholipids consisted of phosphatidylethanolamine, phosphatidylcholine, lysophosphatidylethanolamine
and lysophosphatidylcholine as major phospholipids and minor quantities of phosphatidylinositol, phosphatidylglycerol and
phosphatidic acid. The fatty acid composition of these different neutral lipids, glycolipids and phospholipids were determined. 相似文献