Studies on Extraction and Activity of Peptides from Haemadipsa hainana

[Objectives]Peptides was extracted from Haemadipsa hainana and its activity was studied.[Methods]Electric stimulation,water extraction and ultrasonic extraction were used to extract the peptides from H.hainana.Then the protein content and molecular weight distribution of H.hainana peptides were detected by the BCA method and SDS-PAGE method,respectively.The antithrombin activity and analgesic activity of the three peptide extracts of H.hainana were detected by Markwardt thrombin titration method and mouse hot plate experiment,respectively.[Results]There extraction methods of electric stimulation,water extraction and ultrasonic extraction were used to extract the peptide extract of H.hainana,and the yields were as follows:water extraction>electrical stimulation>ultrasonic extraction.The three peptide extracts from H.hainana had antithrombin activity,and the antithrombin activity was as follows:water extraction>ultrasonic extraction>electrical stimulation.Through the hot plate experiment in mice,it was verified that the three peptide extracts of H.hainana had analgesic activity,and the analgesic activity was water extraction>electric stimulation>ultrasonic extraction.The analgesic activity of high-dose(100 mg/kg)group of H.hainana obtained by water extraction was slightly weaker than that of tramadol.[Conclusions]This study confirmed that the peptide extract of H.hainana had certain antithrombin and analgesic activity,laying a foundation for the subsequent development and application of H.hainana.

Proteomic Analysis of Stichopus japonicus and Evaluation of the Antiaging Properties of Its Peptide

The sea cucumber Stichopus japonicus is one of the"Eight Treasures of Seafood"and contains a number of bioactive components involved in multiple physiological and pharmacological functions.Proteins and peptides are generally considered to be responsible for these beneficial properties.In this study,a total of 3478 proteins and 17390 peptides were identified in Stichopus japonicus by proteomics methods.Among them,4 proteins were involved in 8 metabolic pathways,especially oxidative phosphorylation and cell senescence.Subsequently,lifespan assay and oxidative stress test were performed to investigate the peptides prepared from sea cucumber protein hydrolyzate using the aging model of Caenorhabditis elegans.The results of the anti-aging experiment demonstrated that high-dose peptides significantly prolonged the lifespan of nematodes(30.50%),and improved their capacity to inhibit oxidative stress.The results provide evidence supporting the development of bioactive proteins and peptides derived from Stichopus japonicus as functional foods and lay the foundation for the research of an anti-aging drug.

Proteomic Analysis of Sea Cucumber (Holothuria leucospilota) from the South China Sea

[Objectives]Proteomics methods were used to analyze the total proteome of Holothuria leucospilota in the South China Sea,so as to provide a theoretical basis for elucidating the medicinal material basis of sea cucumber proteins and peptides.[Methods]H.leucospilota was collected from the South China Sea.Label-free proteomics methods were used to detect the protein profile of enzymatically hydrolyzed H.leucospilota total protein,and identify sea cucumber protein and peptide sequences,and gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)bioinformatics analysis software were used to analyze significantly enriched proteins.The String database was used to construct a protein-protein interaction network of significantly enriched H.leucospilota proteins(PPI network).[Results]Proteomics identified 1200 sea cucumber proteins and 2967 peptides.GO analysis and KEGG analysis showed that the four significantly-enriched sea cucumber proteins hsc70,COX,CYTB and rbbp4 participated in 8 metabolic pathways,and COX1 and CYTB among them were significantly related to cardiac muscle contraction,oxidative phosphorylation and metabolic pathways.The PPI network analysis showed that the 13 significantly-enriched sea cucumber proteins had close protein-protein interaction relationships.[Conclusions]This study used proteomics to conduct preliminary identification and research on the proteins and peptides of H.leucospilota,providing a scientific basis for the application of H.leucospilota proteins and peptides in the fields of functional health food and drug research and development.