Study On The Composition Analysis And Antibacterial Mechanism Of Alliin Degradation Products

Garlic is an important edible and medicinal plant.Garlic has multiple biological activities.Modern scientific research indicated that alliin and its analogues were the precursor substances of bioactive functions.This essay mainly studied the antibacterial activity of alliin enzymatic degradation products and alkali heat treatment products,and discussed their antibacterial mechanism and analyzed the composition,and studied the structure-function relationship.In order to find out the functional factor of alliin degradation products,and provide theoretical and technical support for the development of antibacterial products of garlic.The methods and results of the experiments were as follows:In the antibacterial tests of alliin degradation products,The preparation of enzymatic degradation products were prepared as follows:alliin mixed with crude allinase and then reacted lmin,adding trichloroacetic acid(TDA)to terminate the reaction.The preparation of alkali heat treatment products were prepared as follows:alliin mixed with alkali solution,treated 15min under 121?,0.1MPa.The study on the antibacterial activity of alliin degradation products were using the method of agar diffusion method.Antimicrobial test showed that the antimicrobial efficiency is positively correlated with the concentration of degradation products.The enzymatic degradation products are more effective than the alkali heat treatment products.Enzymatic degradation products had antimicrobial activity against bacterium,moulds,actinomycetes.Bacterium were more sensitivity to the alkali heat treatment products than moulds,but the alkali heat treatment products had no antibacterial activity to actinomycetes.The MIC was measured by the double broth dilution method,the MIC of enzymatic degradation products and alkali heat treatment products were 7.81?g·ml-1 and 312.5?g·ml-1.The antibacterial mechanism of alliin degradation,the electrical conductivity of the E.col liquid of the alliin enzymatic degradation products and alkali heat treatment products were increased 11%and 10%,respectively.The 260nm UV-absorption was increased,which showed that the products changed the permeability of cell membrane was destructed.The changes of cell morphology was observed by scanning electron microscope.And the apoptosis and necrosis of the cells were determined by the Hochest33342/PI method.The determination of the utilization rate of bacterial protein was using Kaumas Bradford method,the utilization rate felled by 70%,the results indicated that degradation products restrained the utilization and synthesis of proteins.The degradation products hindered the absorption of phosphorus in the environment,which showed not only destroyed the functional structure of the cell membrane but also interfered with the synthesis of nucleic acids.In the component analysis of alliin degradation products,they were identified as antibacterial substance by GC-MS and HPLC-MS.The sulfur compounds in enzymatic degradation products was more than 80%,which were mainly allyl disulfide and dithiene.The sulfur compounds in alkali heat degradation products was 40%,The rest are alkanes,esters and alcohols.The enzymatic degradation product was prepared by semi-HPLC and analyzed by HPLC-MS-MS.The results showed that the sample was a mixture of glutamine(85%)and methyl ester.