Determination of bioactive compounds in fermented soybean products using GC/MS and further investigation of correlation of their bioactivities

Total phenolic content, antioxidant, tyrosinase and α-glucosidase inhibitory activities of water soluble extracts of noble starter culture Doenjang, a Korean fermented soybean sauce variety

“…Daily ingestion of up to 1 g of polyphenolic compounds from a diet rich in fruits and vegetables is known to have inhibitory effects against mutagenesis and carcinogenesis in humans (Tanaka, Kuei, & Nagashima, 1998). Chai et al (2012) reported Doenjang sample with a total phenolic content of 942 mg/100 g, which is a lower amount than our laboratory prepared starter culture Doenjang products. In addition, the same group reported low phenolic content (197 mg/ 100 g) for soybean seed extract (without fermentation) compared to fermented soybean products of Meju and Doenjang (225 and 209 mg/100 g), which further confirms the benefits of fermented products.…”

“…We hypothesize that the observed anti-tyrosinase activities might be due to polyphenols present in fermented soybean Doenjang products. Since tyrosinase inhibitors repress conversion of tyrosine to DOPA, dopaquinone, and subsequently melanin, various tyrosinase inhibitors have been isolated and studied as potential candidates to reduce melanin content (Chai et al, 2012). In addition, tyrosinase inhibitory activity might be dependent on the hydroxyl group of phenolic compounds, which forms hydrogen bonds with enzyme active sites to promote steric hindrance, conformational changes, and suppression of enzymatic activity.…”

“…Byun et al (2002) also observed no significant difference in tyrosinase inhibitory activities between gammairradiated and non-irradiated Doenjang samples. Chai et al (2012) reported that all fermented soybean products except Meju exhibit effective tyrosinase inhibitory activities. Based on these results, our laboratory-produced starter culture Doenjang samples might be used as a potential treatment for melanin-related disorders and as a skin-whitening agent.…”

Proximate Composition, Phytoconstituents and Mineral Contents of Soybean (Glycine Max) Flour Grown and Processed in Northern Nigeria

“…A small portion of the filtrate was used for the qualitative phytochemical screening using standard methods [16,17].…”

A diterpenoid sugiol from <i>Metasequoia glyptostroboides</i> with α-glucosidase and tyrosinase inhibitory potential

“…Since it has been shown that tyrosinase inhibitors can repress the conversion of tyrosine to DOPA, dopaquinone and subsequently melanin, various tyrosinase inhibitors have been isolated and studied as potential candidates to decrease melanin content. Our results suggest that sugiol derived from M. glyptostroboides might be used as a potential treatment of melanin-related disorders to serve as skinwhitening agent (Chai et al, 2012).…”