Extraction And Purification Of Anthocyanin From Solanum Nigrum And Its Antimicrobial Activity Against Several Pathogens

Anthocyanins,another named Anthocyanidin,is a kind of ubiquitous water-soluble natural pigment existed broadly in plant kingdom.It takes many physiological functions including antioxidant,antibacterial and anti-inflammatory,antitumor and protect eyesight.As the natural products related to the chemical synthesis pigment,it was promising in many fields such as food,health care and medicine.Recently,the international studies were focused on the structural characterization,metabolic synthesis,crude extraction and bioactivity identification.The rare study has been reported to high purification of anthocyanins and the separation of monomers.Alternatively,the studies on anthocyanins were concentrated on grape,blueberry,purple sweet potato,purple corn,black matrimony vine and balck rice,rather than the fruit of Solanum nigrum.This subject mainly focus on the best method of purity detection,technology of extraction and purification,and antimicrobial activity towards several phytopathogens of nightshade anthocyanins.The following conclusions were achieved.Firstly,we comprehensively compared and analyzed the purity of nightshade and blueberry anthocyanins by three different methods including ultraviolet-visible spectrophotometry,high performance liquid chromatography(HPLC)and pH differential method,and determined that HPLC was the optimal detection method of nightshade anthocyanins;Secondly,through the single factor experiments,we optimized the extraction as well as purification process of nightshade anthocyanins,and ascertained the best extraction and eluent agents was aqueous hydrochloric acid solution(p H 1.0)and hydrochloric acid ethanol solution(pH 1.0),respectively.Besides,most of the flavonoids could be removed from the nightshade anthocyanins by extraction three times;Thirdly,by In vitro antifungal activity assay of nightshade anthocyanins against phytopathogens,we found the concentration of nightshade anthocyanins showed a positive correlation with the resistance to Rhizoctonia solani YWK62,Ustilaginoidea virens and Xanthomonas oryzae RS105.Taken together,it is expected to provide the theoretical basis reference for the purity detection,extraction,purification process and application in plant disease prevention.