Résumé
An alpha-amylase inhibitor (alpha-AI) was isolated from white kidney beans (Phaseolus vulgaris L) by ethanol fractional precipitation, ion exchange chromatography and gel filtration column chromatography. It was a homogeneity glycoprotein demonstrated by SDS-PAGE and gel filtration on CL-6B. The glycoprotein contained 88.2% protein and was rich in aspartic acid, glutamic acid, leucine, threonine and serine. The carbohydrate moiety was consisted of Man, Glc, Gal and Xyl in a mole ratio of 2.42: 1.50: 1.52: 1.00. The glycan and the core protein backbone was connected by O-linkage as determined by beta-elimination reaction. The continuous oral administration of the alpha-AI (150 mg x kg(-1) x d(-1)) for 7 days can lower fasting blood glucose and 300 mg x kg(-1) x d(-1) alpha-AI for 7 days can improve the sugar tolerance on alloxan-dependent diabetic model rats. The result showed the alpha-AI obtained from white kidney beans had good hypoglycemic effect on alloxan induced diabetic rats and may have high potential pharmaceutical value as a regulative digestive-starch degradation in patients suffering from diabetes.
Sujets)
Animaux , Femelle , Rats , Alloxane , Acides aminés , Glycémie , Métabolisme , Diabète expérimental , Sang , Glycoprotéines , Chimie , Pharmacologie , Masse moléculaire , Oses , Phaseolus , Chimie , Lectines végétales , Chimie , Pharmacologie , Plantes médicinales , Chimie , Rat Sprague-Dawley , Protéines de légume , alpha-AmylasesRésumé
<p><b>AIM</b>To synthesize gastrodin via biotransformation of microorganism using p-hydroxybenzaldehyde as substrate.</p><p><b>METHODS</b>Using resting cell techniques with TLC and HPLC analysis, a strain of Rhizopus chinensis Staito AS3. 1165 which has the capability of biotransforming p-hydroxybenzaldehyde into gastrodin was screened from 50 strains of microorganisms. Preparative scale biotransformation was carried out under the optimal transforming condition. The product was obtained by chromatography, and characterized on the basis of its physical and spectral data.</p><p><b>RESULTS</b>The product was identified as gastrodin on the basis of its 1H NMR, 13C NMR and EI-MS spectral data.</p><p><b>CONCLUSION</b>The fact that gastrodin could be synthesized by microbial transformation implies a new approach to gastrodin production. As a result, this research will be of a great economic and social value.</p>