Studies On The Anti-aging Efficacy Of Milk-derived Peptides

Milk-derived peptides,as a kind of bioactive substances can be hydrolyzed from the milk protein under the help of probiotics and active hydrolase,which own the characters of strong activities,good absorbtion,non-toxicity and hypo-allergenic.Currently,the physiological activities of milk-derived peptides are mainly divided into anti-aging,antihypertensive,immune regulation and antibacterial effections,which has wide application prospect in terms of human health.This experiment was mainly distributed into two parts:(1)the absorption and physiological regulation research of DELQ and QEPV in the E.coli OP50 model.(2)the effective dosage,safty,the anti-aging function and absorption research of DELQ,QEPV and mixed peptides(DELQ: QEPV=1: 1)in the C.elegans model.In the first part,the E.coli OP50 model was cultured with different concentrations of DELQ and QEPV to inspect its growth and cell apoptosis,and utilizing peptides marked with fluorescent to test its absorption in E.coli.The results show that,experimental group and blank group don’t perform distinct difference in OD and MTT growth cruve.In the same time,we canot detect the fluorescent marked peptides in the cell.In conclusion,DELQ and QEPV cannot be absorbed by E.coli,which leads to the poor physiological adjustment in E.coli and eliminates the pathway of C.elegans absorbing the peptides through consumption of E.coli.In the second part,C.elegans were used as experimental model to study the anti-aging efficacy of DELQ,QEPV and mixed peptides,which were treated with different concentrations of those,tested by reproductive capacity assay to determine the effective dosage.The safety was verified by the length and athleticism.Then the anti-aging function was demonstrated by the lifespan.The synchronized L4 s were treated to explore the initial mechanism of anti-aging function,in which the indexes of fecundity,acute heat and oxidative stress were included.In the end,the results were verified by fluorescent marked peptides absorbing experiment.The results show that,(1)400mg/L DELQ,QEPV and 300mg/L mixed peptides were the optimum concentrations;(2)experimental group and blank group showed no difference on the length and athleticism to prove the safety;(3)experimental group performed better than the blank group in the average life expectancy,half the time of death,and the longest life span,which also proved DELQ and QEPV owned anti-aging efficacy;(4)under the condition of oxidative stress,experimental survival rate was significantly higher than the blank group,the MOD,ROS and SOD value were all have significant changes,but not in heat stress,so we speculated that the anti-aging activity of peptides was performed by scavenging free radicals to achieve rather than improve its heat resistance;(5)DELQ and QEPV were absorbed by C.elegans directly,rather than indirectly through ingestion of E.coli.So we can get to the conclusion that DELQ and QEPV own the efficacy of anti-aging.