Scenedesmus obliquus: Antioxidant and antiviral activity of proteins hydrolyzed by three enzymes

PURPOSE: To obtain protein hydrolysates from fresh water green algae Scenedesmus obliquus by three different enzymes and evaluate its antioxidant and antiviral activity. METHODS: Enzymatic hydrolysates of green algae Scenedesmus obliquus protein were prepared by treatment with: 1.2% solution of pepsin, trypsin or papain. Protein was extracted from S. obliquus by three different extraction methods. Protein extracts and hydrolysates were assessed from stained gels following SDS–PAGE of samples. Antioxidant activity of protein hydrolysates was investigated. RESULTS: S. obliquus cells and protein extracts were rich in Arg, Lys, Asp, Ala, and His. Protein hydrolyzed by papain (Sd1pa) and protein hydrolyzed by trypsin (Sd2Try) induced highest antioxidant activity based on 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging (41.41% and 40.62%) respectively, and on 2,2′-azinobis 3-ethyl-benzothiazoline-6-sulphonate (ABTS) radical (87.03% and 45.12%) respectively, at 150 µg/ml. The inhibitory effect and mode of action of protein hydrolysates were evaluated against Coxsackie B(3) virus (CVB(3)). Protein hydrolyzed by papain (Sd2pa) and protein hydrolyzed by pepsin (Sd1pep) at 100 µg/ml exhibited antiviral activity (66.2% and 57.6%, respectively), against (CVB(3)) from all protein hydrolysates. CONCLUSION: S. obliquus protein hydrolysates have a potential as antioxidative neutraceutical ingredients and a potential therapeutic agent against CVB(3).