Antioxidant Activity of Gelatins from Sika Deer (Cervus nippon)

Background: In Japan, the rapid increase in the number of sika deer (Cervus nippon) has become a social issue and measures for the resource utilization of extensively captured sika deer have not kept pace. In contrast, various body parts of deer have been used in traditional Chinese medicine since ancient times. Objectives: In the present study, the in vitro antioxidant activity of gelatins from sika deer was evaluated in order to increase their usefulness as health promoting resources. Materials and Methods: Three kinds of deer gelatins were prepared through hot water extraction of antlers, skins, or bones obtained from sika deer. The antioxidant activity was evaluated along with commercially available gelatins and collagen peptides from donkey, bovine, pig and fish using three kinds of in vitro antioxidant assays including DPPH free radical scavenging activity (DPPH) assay, Superoxide anion scavenging activity (SOD) assay and Oxygen Radical Absorption Capacity (ORAC) assay. Results: All kinds of gelatins from deer exhibited more than 50% inhibition of DPPH free radical and superoxide anion scavenging activities, as well as H-ORAC values exceeding 8,000 μmol TE/L. The gelatins from deer were further separated into high molecular-weight and low molecular-weight fractions by ethanol precipitation method and the low molecular-weight fractions showed stronger antioxidant activity than corresponding high molecular-weight fractions in all measurements. Conclusion: The result of present study provided rudimentary evidence for the antioxidant activity of gelatins from sika deer, which need further research for the use as health promoting resources.