Natural Product Communications
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2014
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IF 0.924
Zihao Zhou,Jun Tang,Xueping Song
The chemical composition of the essential oil from roots and rhizomes of Ligularia hodgsonii was analyzed by gas chromatography (GC) and GC-mass spectrometry (MS). Forty-seven components were identified, representing 77.0% of the total oil. The main constituents were l-(+)-ascorbic acid 2,6-dihexadecanoate (15.7%), selina-6-en-4-ol (8.4%) and 9,10-dimethyl-1,2,3,4,5,6,7,8-octahydroanthracene (6.6%). The free radical scavenging activities of the essential oil, aqueous extract, ethanolic extract, and crude polysaccharides of L. hodgsonii, as well as some of their major components, were investigated using DPPH and ABTS assays. The essential oil displayed a lower capacity to quench free radicals than the extracts; the ethanolic and aqueous extracts showed considerably higher antioxidant potential that deserves further study.
研究领域:
植物化学
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药理学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2015
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IF 4.169
L.X. Chen,D.J. Hu,S.C. Lam,L. Ge,D. Wu,J. Zhao,Z.R. Long,W.J. Yang,B. Fan,S.P. Li
Snow chrysanthemum ( Coreopsis tinctoria Nutt.), a world-widely well-known flower tea material, has attracted more and more attention because of its beneficial health effects such as antioxidant activity and special flavor. In this study, a high performance liquid chromatography coupled with diode array detection and mass spectrometry (HPLC-DAD-MS) and 2,2′-azinobis(3-ethylbenzthiazoline-sulfonic acid)diammonium salt (ABTS) based assay was employed for comparison and identification of antioxidants in different samples of snow chrysanthemum. The results showed that snow chrysanthemum flowers possessed the highest while stems presented the lowest antioxidant capacities. Fourteen detected peaks with antioxidant activity were temporarily identified as 3,4′,5,6,7-pentahydroxyflavanone-O-hexoside, chlorogenic acid, 2R-3′,4′,8-trihydroxyflavanone-7-O-glucoside, flavanomarein, flavanocorepsin, flavanokanin, quercetagitin-7-O-glucoside, 3′,5,5′,7-tetrahydroxyflavanone-O-hexoside, marein, maritimein, 1,3-dicaffeoylquinic acid, coreopsin, okanin and acetyl-marein by comparing their UV spectra, retention times and MS data with standards or literature data. Antioxidants existed in snow chrysanthemum are quite different from those reported in Chrysanthemum morifolium , a well-known traditional beverage in China, which indicated that snow chrysanthemum may be a promising herbal tea material with obvious antioxidant activity.
研究领域:
植物化学
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食品科学
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药用植物研究
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DOI
高影响因子
Natural Product Communications
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2015
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IF 0.906
Jian-Wei Dong,Le Cai,Yun Xing,Jing Yu,Zhong-Tao Ding
2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS•+) is a stable free radical frequently used for estimating the total antioxidant capacity (TAC) of natural products. The existing methods for ABTS•+ radical-scavenging activity assays are diverse in pre-diluting solvents and reaction time, which lead to errors in the TAC estimations. To develop an effective and universal method for estimating the ABTS•+ capacity accurately and reasonably, five pre-dilution solvents [methanol, ethanol, phosphate buffer (Na2HPO4-NaH2PO4, 200 mM, pH = 7.4), PBS buffer (Na2HPO4-NaH2PO4-NaCl, 200 mM, pH = 7.4), and distilled water] and different reaction times were investigated in ABTS•+ assays of five typical antioxidants. The results showed that the solvent effects were very significant. When using different pre-diluting solvents, different detection wavelengths should be selected. ABTS-+ assay could be measured within 2–10 min to obtain a rough result, which was mostly 6 min in the literature. However, full and accurate evaluation of antioxidant reactivity rather than capacity requires recording ABTS•+ loss continuously during the whole reaction period. The present study makes a recommendation for estimating the ABTS•+ capacity accurately and reasonably.
研究领域:
生物化学
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分析化学
✓ 已验证
DOI
高影响因子