Protective Effects Of Tree Peony Seed Protein Hydrolysate On Damage Of Zebrafish And Oil Oxidation

Tree peony seed protein hydrolysate(AL-TPSPH)is a natural active ingredient extracted from tree peony seed meal.This topic explored protective effects and mechanisms of AL-TPSPH on damage in zebrafish embryos induced by Cd and terfenadine.And protective effects of AL-TPSPH on lard quality were also explored.The results are as follows:(1)Cd-induced developmental damage model of zebrafish embryos was established to investigate protective effects of AL-TPSPH.Results showed that 75μg/m L AL-TPSPH significantly increased hatching and survival rates of Cd-induced zebrafish embryos(P < 0.05).It also significantly decreased malformation rates of embryos,especially malformation rate of spinal curvature(P < 0.05).These results indicated that AL-TPSPH had good protective effects on Cd-induced developmental damage in zebrafish embryos.(2)The protective mechanisms of AL-TPSPH on Cd-induced developmental damage in zebrafish embryos were investigated.Results showed that AL-TPSPH decreased MDA concentration and increased total antioxidant capacity(T-AOC),GSH/GSSG ratio,activities of antioxidant enzymes(SOD,CAT and GPx)and expression levels of related genes(Mn-SOD,CAT and GPx1a)in Cd-induced zebrafish embryos.AL-TPSPH down-regulated the expressions of inflammatory genes(TNF-α,IL-1β and IFN-γ)and apoptosis-related genes(C-jun,Caspase-3 and Caspase-9)in Cd-induced zebrafish embryos.These results suggested that AL-TPSPH reduced Cd-induced developmental damage in zebrafish embryos by reducing oxidative stress,inflammation and apoptosis.(3)AL-TPSPH was separated by ultrafiltration.And five ultrafiltration fractions with molecular weight(Mw)> 30 k Da,10-30 k Da,5-10 k Da,3-5 k Da and < 3 k Da were obtained.Terfenadine-induced cardiac damage model of zebrafish embryos was established to study protective effects of AL-TPSPH including mixed fractions and five ultrafiltration fractions.The results showed that all fractions of AL-TPSPH reduced heart malformation rate and decreased pericardium area,distance of sinus venosus(SV)and bulbus arteriosus(BA)and increased heart rate in terfenadine-induced zebrafish embryos.The mixed and Mw 5-10 k Da fractions of AL-TPSPH significantly up-regulated the expressions of cardiac transcription factors(Nkx2.5,Tbx5 and Gata4)and oxidative stress-related genes(Mn-SOD,Cat,Gstp2,Nqo1 and Nrf2)in terfenadine-induced zebrafish embryos(P < 0.05).Meanwhile,the mixed and Mw 5-10 k Da fractions up-regulated the expressions of Mdm2 and Bcl-2,and down-regulated the expressions of P53,Bax,Caspase-9 and Caspase-3 in terfenadine-induced zebrafish embryos.These results suggested that AL-TPSPH especially the mixed and Mw 5-10 k Da fractions,could protect terfenadine-induced cardiac damage in zebrafish embryos by regulating cardiac transcription factors,oxidative stress and apoptosis.(4)Lard was treated by oven method to study the protective effects of mixed and five ultrafiltration fractions of AL-TPSPH on lard quality.The results showed that sensory evaluations of lard with Mw 5-10 k Da,3-5 k Da and < 3 k Da fractions were similar with BHT.Mw 5-10 k Da fractions had the best inhibitory effect on the peroxidation value of lard.And the peroxidation value was only 0.0241 mmol/kg when storage time was 25 days,which was lower than BHT(0.0245 mmol/kg).Mw 5-10 k Da fractions also had the best protective effect on decrease of iodine value of lard.Mw10-30 k Da fractions had the best protective effect on acid value.Except for Mw 10-30 k Da fractions,all fractions of AL-TPSPH had significant inhibitory effects on the elevation of malondialdehyde(P < 0.05)These results indicated that AL-TPSPH had good protective effects on qualit>y of lard during storage.Among all fractions,Mw5-10 k Da fraction had the best anti-oil oxidation ability.