Pearl Mother Cooked Before And After Separation Of Oligopeptides Purification And Activity Comparison Study

Mother-of-pearl is shells of Unionidae animals such as Hyriopsis cumingii (Lea), Cristaria plicata (Leach), Pteria martensii (Dunker). As a kind of traditional Chinese medicine, it is contained in various versions of pharmacopoeia. Mother-of-pearl has the effect of calming the liver, suppressing yang, arresting convulsion and improving acuity of vision.That can be used for headache, dizziness, fidgety, insomnia, hepatic heat, red eyes, hepatic asthenia and dysopia.In this study, we conducted a decoction extraction to three kinds of mother-of-pearl samples such as crude products, submicron powder and processed products. We could find the yield of submicron powder and processed products were higher than that of raw products by comparison. Therefore we could conclude the dissolution rate would be higher if degree of grinding of mother-of-pearl became higher or had been concocted already. So we selected mother-of-pearl via superfine grinding of crude products and processed products for our experimental materials.We adopted Hydroxyl radical scavenging method to research the anti-oxidant activity of water extract of freeze-dried powder of mother-of-pearl crude products and processed products. Results showed that mother-of-pearl crude products and processed products all have a certain degree of anti-oxidant activity, but the capacity of anti-oxidant of mother-of-pearl processed products was obviously seven times stronger than that of mother-of-pearl crude products. All above cleared and definited its anti-oxidant active ingredients further and pointed out the direction for extraction and separation of mother-of-pearl in future.We used Biuret and Phenol-sulfuric acid method to survey and evaluate total peptide and sugar content of crude products and processed products of mother-of-pearl. The results showed that total peptide content of mother-of-pearl crude products was 0.0895% and sugar content of that was 0.000478% while what were0.085% and 0.0001088% in processed products of mother-of-pearl. The diversification of peptide composition of mother-of-pearl concocted in hot conditions provided the basis for the modern theory of heat shock according with peptide bond theory of heat shock. Simultaneously, changes in sugar content made clear that the stability of anhydride group O-glycosidic bond with a strong electron-withdrawing ability was weaker than N-glycosidic bond and peptide bond, so it was easier to break than the peptide bond.The crude products′active site of mother-of-pearl was determined through activity tracking. We could get a further purified single oligopeptide compounds from freeze-dried powder of mother-of-pearl crude products by repeated column chromatography and high-performance liquid. Application the spectroscopy techniques and peptide bond fragmentation was deduced its structure.we could appraise the structure was COOH-N-V-A-NH2, three-peptide compounds with the molecular weight of 303. This was the first isolated from the mother-of-pearl.We adopted LC-MS techniques to analyze peptide mixture in crude products and processed products of mother-of-pearl, and we could speculate the structure of the four compounds preliminary. Respectively, they were dipeptide m/z for 218, dipeptide m/z for 232, tripeptide m/z for 303, tetrapeptides m/z for 374. These compounds were first identified in mother-of-pearl.