Preparation of Chlorella vulgaris polysaccharides and their antioxidant activity in vitro and in vivo.
Int J Biol Macromol. 2019 Jun 28 ;137:139-150. Epub 2019 Jun 28. PMID: 31260772
In the present study, six different polysaccharides (RFPs, MAPs, UWPs, AEPs, HWPs and CEPs) were extracted from Chlorella vulgaris using repeated freeze-thawing, microwave-assisted-, ultrasonic wave-, alkali-, hot water-, and cellulase-based methods; and antioxidant property assays were performed both in vitro and in vivo. Radical-scavenging capacity (using DPPH, superoxide and hydroxyl radicals) and metal chelating ability were assessed in vitro; Caenorhabditis elegans was used to assess antioxidant effects in vivo. Based on the in vitro screening tests, UWPs exhibited high antioxidant capacity. The UWP yield was 17.1% ± 2.2%; the DPPH-, superoxide-, and hydroxyl radical-scavenging rates were 65.1% ± 2.4%, 61.2% ± 2.7%, and 56.2% ± 2.2%, respectively, and the metal chelating ability was 63.6% ± 2.5% at a concentration of 0.4 mg/mL. UWPs also exhibited high antioxidant activity in vivo.UWPs significantly increased the lifespan of C. elegans under oxidative stress induced by hydrogen peroxide compared with the control group, enhanced stress-resistance-related enzymes, including catalase and superoxide dismutase by 7.29% ± 1.8% and 24.41% ± 4.8%, respectively. The resultsof the present study indicate that the extraction methods of C. vulgaris polysaccharides were a key factor influencing antioxidant activity.