(582dm) Tyrosinase–Inhibitory and Antioxidant Activities of Oligopeptides From Yeast Protein Hydrolysate

Yeast(Saccharomyces cerevisiae) proteins were separately hydrolysed using four different types of proteases to study antioxidant and tyrosinase-inhibitory of their peptides. The antioxidant and tyrosinase inhibitory activities of yeast peptide were mainly influenced by hydrolysis time and enzyme type. The result revealed that papain hydrolysate obtained after 30min hydrolysis (PYPH) displayed a higher DPPH radical scavenging activity and the highest mushroom tyrosinase-inhibitory activity. PYPH also showed good superoxide anion and hydroxyl radical scavenging, effective lipid peroxidation activities, and copper-chelating inhibition. Then PYPH was purified sequentially by ultrafiltration, gel filtration, and data showed the peptide with molecular weight below 5 KDa (PYPH-III) had the strongest tyrosinase–inhibitory and antioxidant activities. Further fraction separation and purification are being carried out on RP-HPLC and by LC-MS/MS to identify the amino acids sequences. It is expected that PYPH and/or its isolated peptides may be useful as cosmetics and food ingredients, especially in cosmetics as whitening agent. Because compared with ordinary whitening agent, it is not only good tyrosinase inhibitory performance, but also can provide nutrients for the skin.