Antioxidant Activities of Black Soybean Extract (Glycine max (L.) Merr.) and Daidzein as Hydroxyl and Nitric Oxide Scavengers

Free radicals are known as a leading factor in aging. Nitric oxide (NO) and O-2 center dot-have been shown to inhibit the synthesis of matrix components and stimulate prolidase activities involved in collagen degradation. Hydroxyl (center dot OH) radical is a precursor of hyaluronic acid degradation. Antioxidants act as a scavenger for free radicals, creating a possibility to use them to prevent the aging process. Black soybeans (Glycine max (L.) Merr.) contain bioactive compounds that have the ability to scavenge free radicals, including daidzein. Daidzein belongs to the isoflavones group which is the most active compound in black soybean. This study aimed to understand the antioxidant activities of the black soybean extract (BSE) and daidzein compound in the scavenging of 'OH and NO radicals and was performed at the Aretha Medika Utama-Biomolecular and Biomedical Research Center (BBRC), Bandung, Indonesia, from September to November 2018. The scavenging activity of center dot OH was assessed using the deoxyribose method, while the assessment of the scavenging of NO radicals was carried out using the sodium nitroprusside method. BSE and daidzein had an center dot OH scavenging activity with an IC50 value of 71.07 mu g/mL, followed by daidzein with 24.57 mu g/mL. A higher NO scavenging activity was seen in BSE with an IC50 of 71.60 mu g/mL followed by daidzein with 35.68 mu g/mL. Daidzein has a higher antioxidant activity through hydroxyl and nitric oxide scavenging compared to Glycine max (L.) Merr extract. Hence, daidzein has a higher potential as an anti-aging agent based on the free-radical theory of aging.