Preparation Of Essence From Corbicula Fluminea And Investigation Of Its Active Substance

corbicula fluminea is one of important economic shellfish in China.Its meat is tender and rich in nutrition;it also has many medicinal effects.Poyang Lake Freshwater Shellfish-Corbicula Fluminea has been used as raw materials to produce an aquatic flavouring with Uhrasonic-assisted extraction technology in this paper.Polypeptide products and polysaccharide products were obtained by enzyme engineering and biotechnology,the physico-chemical properties and functional properties were studied.The main research contents and results were as follows:?1?Ultrasound-assisted extraction was adopted to extract water-soluble protein from corbicula fluminea.the extraction yield of water-soluble protein was regarded as an index to research the best extraction process conditions.solid-to-liquid ratio,extracting time,extracting temperature,uhrasonic power were as factors affects,using response surface analysis to optimize design moreover the anti-oxidation effect of extract was researched.The results showed that,solid to liquid ratio?m/V?1:20,extracting time 23 min,extracting temperature 48?,ultrasonic power 920 W were the best conditions.Under this condition,water-soluble protein extraction rate was 67.7%.The activity of scavenging DPPH(IC₅₀=0.051%),superoxide free radical(IC₅₀=0.029%)and iron reduction capability?The FRAP was 148.46?mol/mg when concentrations of protein was 0.135%?were stronger than hydroxyl radical.?2?With TCA-SN as indicators,Compared several different enzymes for protein hydrolysis effect.The results indicated that Alcalase was the best hydrolytic enzymes.Hydrolysis temperature,hydrolysis time,the dosage of enzyme,p H,the substrate concentration were as factors affects.The hydrolysis parameters was defined by the orthogonal test.The results showed that the temperature was 50?,the dosage of enzyme was 2%,the substrate protein concentration was 2%,the pH was 8.5,time was3 h,which the TCA-SN was 26.95%.The adsorption capacity of several different macroporous adsorption resins?MAR?for Corbicula Fluminea peptides were investigated.The DA201-C MAR had the optimum adsorption property for Corbicula Fluminea peptides,The best condition was feeding amount 1BV/h,feeding concentration was 30 mg/m L,Ethanol elution volume fraction was 75%,eluent were decompressed enrichment and freeze-drying,The percentage composition of peptides was 82.19%.?3?The functional properties and antioxidation activity of Corbicula Fluminea polypeptide were studied.The functional properties including foaming ability and foam stability,protein solubility,thermostability,oil absorption were tested,Then the relative molecular weight and amino acids composition were identified by high performance liquid chromatography?HPLC?and amino acid analyzer respectively,Antioxidation activity was researched by measuring the scavenging rates to DPPH·,·OH,O^2-·and iron reduction capability,The results showed that the functional characteristics were very well by measuring foaming and foam stability,solubility,thermal stability and oil absorption.the relative molecule weight of Corbicula Fluminea polypeptide is in the range of 70-2 000 Da,the peptides that number-average the relative molecular weight about 72 Da were the most,about 36.38%.The contents of essential amino acids and flavor amino acids were high,about 42.69%,34.88%respectively.The activity of scavenging DPPH(IC₅₀=2.55 mg/mL)and iron reduction capability?The FRAP was 95.52 umol/mL when peptide concentration was 1mg/ml.?were stronger than superoxide free radical and hydroxyl radical.?4?The crude Corbicula fluminea polysaccharide were purified by DEAE-52cellulose anion-exchange column chromatography and Sephadex TMG-100 gel-filfration column chromatography successively.Two mainly fraction,named as CFP-1 and CFP-2,were obtained.Results of Uv spectroscopy scanning showed that CFP-1and CFP-2 contained a few protein,as evident by no significant absorption peaks in260-280 nm place.In FTIR spectrum,characteristic absorptions of polysaccharides,carboxyl group and beta pyranoid glycosidic bond were all observed in CFP-1 and CFP-2.Purity of CFP-1 and CFP-2 was further confirmed by using HPLC,and the results showed that it was Corbicula fluminea polysaccharide and the average the relative molecular weight are1172 kD and 3627 kD.Proliferation inhibitory activities of CFP-1 and CFP-2 for tumor cell lines?Hep G2?were evaluated by MTT assay.The result showed that CFP-1 could significantly inhibit proliferation of HepG2 than CFP-2,In addition,radical scavenging tests revealed that CFP-2 showed significant function of antioxidation activity.In summary,this paper separated and purified the naturally occurring small molecule peptides and polysaccharide in Corbicula Fluminea and studied their biological activity.Systematic steps of separation and purification on polypeptide and polysaccharide from Corbicula Fluminea were developed.Our results provided a theoretical foundation for the in-depth study of the clam polypeptides,and are expected to promote the development in the field of functional food and drug utilization of the Corbicula Fluminea.