http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Chemical Composition and Active Antioxidants of Eucommia ulmoides Oliv. Bark
Guan-Zheng Qu,Chuan-Ling Si,Yu Yin,Myeong-Hyeon Wang 한국영양학회 2006 Nutritional Sciences Vol.9 No.4
??Chemical composition of the Eucommia ulmoides bark, including extractives, proximate, mineral, fatty acid and monosaccharide compositions, was studied The most abundant mineral was calcium (533.17 ㎎/100 g). α-linolenic acid (24.7%) and linoleic acid (24.3%), showed higher contents among the fatty acids. Major monosaccharides of E. ulmoides bark were arabinose (13.94 ㎎/g), xylose (18.91 ㎎/g) and glucose (119.7 ㎎/g). From the bark of E. ulmoides, four compounds were isolated and their structures were elucidated as caffeic acid (Ⅰ), kaempferol (Ⅱ), quercetin (Ⅲ) and isoquercitrin (Ⅳ) by spectroscopic analysis such as NMR and MS, including cellulose TLC and other chemical evidence such as hydrolyzation and acetylation. The antioxidant activities of four isolated compounds were evaluated by DPPH free radical scavenging, hydroxyl scavenging and reducing power assays. The results indicated that all the isolated compounds showed higher DPPH radical scavenging activity than α-tocopherol and BHT that were used as positive controls and these four compounds exhibited considerable reducing power and hydroxyl radical (OH') scavenging activity. Considering from the results above, it suggests that the E. ulmoides bark is a potential natural source of antioxidant material.
Antioxidant Constituents from Leonurus japonicus
Guan-Zheng Qu,Chuan-Ling Si,왕명현 한국생약학회 2006 Natural Product Sciences Vol.12 No.4
phenolic acids, gallic acid (1) and syringic acid (2), and five flavonoids, apigenin (3), luteolin (4),kaempferol (5), quercetin (6), and myricetin (7), were isolated from the aerial parts of Leonurus japonicus. Theirstructures were elucidated by chemical and spectral analysis. The antioxidant activities of the crude extracts,partitioned fractions and isolated compounds were evaluated by DDPH fre radical-scavenging assay. Resultssuggested that the EtOAc partitioned fraction and compounds 1, 4, 5, 6, and 7 showed significantly highα-tocopherol and BHT, which were used as controls.KeywordsAerial parts, antioxidant, constituents, Leonurus japonicus
Antioxidant and Antidiabetic Activities of Eucommia ulmoides Bark
Qu, Guan-Zheng,Heo, Seong-Il,Wang, Myeong-Hyeon The Korean Society for Applied Biological Chemistr 2006 Journal of Applied Biological Chemistry (J. Appl. Vol.49 No.3
Eucommia ulmoides bark extracts by cold water, boiling water, 100% EtOH, 70% EtOH, 100% MeOH, 70% MeOH and $CHCl_3$ were assayed for their medicinal effects. The antioxidant activity of the extracts ranged from $IC_{50}$ 125.2 to $IC_{50}\;872.7{\mu}g/ml$ in the 1,1-diphenyl-2-picrylhydrazyl (DDPH) free radical-scavenging assay, and cold water extracts had the highest antioxidant activity. $CHCl_3$ extracts had the highest inhibitory effect on angiotensin I-converting enzyme (ACE) giving inhibition of up to 56.4% at a concentration of 1 mg/ml. Extracts in 100% EtOH had the greatest inhibitory effect on $\acute{a}-amylase$ activity ($IC_{50}=174.6{\mu}g/ml$), and 70% MeOH extracts had the greatest inhibitory effect on ${\alpha}-glucosidase$ activity ($IC_{50}=14.0{\mu}g/ml$). Taken together, these results provided the in vitro evidence on the ACE, amylase and glucosidase inhibitory actions of E. ulmoides bark that form the pharmacological basis for its antihypertensive and antidiabetic action.
Antioxidant, Antidiabetic and Cytotoxic Effects of Eucommia ulmoides Oliv. Bark in vitro
Qu, Guan-Zheng,Lee, Sung-Hyun,Wang, Myeong-Hyeon The Korean Society for Applied Biological Chemistr 2006 Journal of Applied Biological Chemistry (J. Appl. Vol.49 No.4
The aim of this study is to investigate in vitro biological properties of Eucommia ulmoides Oliv. bark. Ethyl acetate(EtOAc) fraction from aqueous extract of Eucommia bark showed strong antioxidant activity of $IC_{50}$ 19.2 ${\mu}g/ml$ by 1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical-scavenging assay. The Eucommia bark extract showed $\alpha$-glucosidase inhibitory activity and inhibited growth of human liver cancer cell, suggesting its potential biological value of anticancer.