The Study Of Oolong Tea Polyphenols On The Role Of Digestive Enzymes

Obesity is caused by the anabolic of fat cells greater than catabolism.By reducing blood glucose,fatty acids and cholesterol levels,can we reach a certain weight loss.In ancient,Oolong tea had slimming effect.Oolong tea is a unique kind of semi-fermented tea,which has a long history of production at home and abroad.Oolong tea contains a complex chemical composition,mainly tea polyphenols,pigments,alkaloids,amino acids,carbohydrates and so on.The main component of Oolong tea is tea polyphenols,which is the primary function of weighting loss ingredients in Oolong tea.In recent years,numerous studies have demonstrated that the most abundant catechin polyphenol monomer EGCG,and methylated forms EGCG3 "Me,played an important role in lossing weight.Based on the current research status,Oolong tea polyphenols and monomer EGCG,EGCG3"Me were extraced and purificated with Chinese Oolong tea as raw material.And the inhititory effect of Oolong tea polyphenols,EGCG and EGCG3"Me on digestion enzyme,such as a-amylase,a-glucosidase and pancreatic lipase,bovine serum albumin were studied.The main findings are as follows:1.Oolong tea polyphenols,EGCG and EGCG3"Me were separated and purificated from specific varieties of Oolong tea.Crude extract of Oolong tea was passed through columns of polyamide,by eluting with water and 80%ethanol.And then the mixture was loaded on a specific macroporous resin(HW-40),eluted with ethanol and the fraction were collected,to obtain EGCG and EGCG3"Me monomer of high purity(95%).And the chemical structures of the monomers were determined by ESI-TOF-MS and ~1H-NMR.2.The inhititory effect of Oolong tea polyphenols,EGCG and EGCG3"Me on a-amylase,a-glucosidase and pancreatic lipase were studied.By enzyme kinetics experiment,inhibition rate and types were investigaed.UV spectrophotometer showed that three samples made the enzyme's change in wavelength.Fluorescence spectrophotometer showed that with the addition of three samples,the structures of digestive enzymes were changed,further influenced the inhibition mechanism of the enzyme.These results showed that three samples all have strong inhibition and quenching effect on the digestive enzymes.3.The binding of Oolong tea polyphenols,EGCG and EGCG3"Me with bovine serum albumin,P-lactoglobulin protein.Using 3D fluorescence wavelength scanning and synchronous fluorescence methods to study and explore the binding mechanism.They all have a strong ability to bind and inhibit protein,which quenched by phenolic hydroxyl group and hydrophobic forces.The quenching mechanisms are dynamic quenching.