The bioactive peptide screening from Torreya grandis meal protein hydrolysates

Torreya grandis has been an economic forest crop in China for a long history. The side products of T. grandis oil would cause environmental problems and financial burden. Hydrolyzation of T. grandis meal protein can better utilize T. grandis and reduce its side products. The current study systematically investigated the enzymolysis of T. grandis: Alkaline proteinase was screened from five enzymes; when degree of hydrolysis at 12%; the hydrolysates exhibited the best antioxidant capacity; enzymatic model was fitted as DH = 4.55ln[1+(4.29E0/S0-0.07)t)] (DH: degree of hydrolysis); the investigations of amino acid compositions of T. grandis protein and its hydrolysates showed that amino acids supplementary would be necessary to optimize better bioactivity; the results of antioxidant capacity varied due to different dominant factors (i.e., molecular weight, amino acid compositions, peptide structures, etc.); the discrepancy of predict and actual solubilities could be caused by influences of peptide structures; foaming capacity was uncorrelated with molecular weight; low molecular weight of T. grandis protein hydrolysates presented poor foaming stability; emulsifying stability of T. grandis protein hydrolysates was affected more by the hydrophobic amino acid composition than molecular weight. This comprehensive study and investigated processes are useful that can be utilized to different natural product developments (including T. grandis).