• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.35 no.3
• /
• pp.203-208
• /
• 2009

Doenjang (Korean fermented soybean paste) is a unique fermented food in Korea. It has been traditionally manufactured from soybeans, by Jang Yang process. We focused on the newly formed compound in highly aged Doenjang and its biological activity. One new o-dihydroxyisoflavone, 7,3',4'-trihydroxyisoflavone and two known o-dihydroxyisoflavone derivatives were isolated from 5-year-old Doenjang and evaluated as potent antioxidant and whitening effect by comparing with other known isoflavone. 7,8,4'-Trihydroxyisoflavone (compound 1), 7,3',4'-trihydroxyisoflavone (compound 2) and 6,7,4'-trihydroxyisoflavone (compound 3) inhibited DPPH (diphenyl-1-picrylhydrazyl) formation by 50 % at a concentration of $21.5{\pm}0.2$, $28.7{\pm}0.4$ and $32.6{\pm}0.6$ ($IC_{50}$) respectively, whereas daidzein showed weak DPPH radical scavenging activity. In superoxide scavenging effect were measured in one assay. Compound 1 ($IC_{50}=18.10{\pm}0.2{\mu}M$) and 2 ($IC_{50}=10.54{\pm}0.4{\mu}M$) show significant inhibitory activity and greater effect than L-ascorbic acid. But compound 3 and daidzein showed lower inhibition activity. Also, o-dihydroxyisoflavone derivatives evaluated as potent inhibitors on tyrosinase activity and melanin formation in melan-a cells. Compound 1 ($IC_{50}=11.21{\pm}0.2{\mu}M$), compound 2 ($IC_{50}=5.23{\pm}0.6{\mu}M$) exhibited significant inhibitory effect on tyrosinase activity. Furthermore, those compounds are significantly suppressed the cellular melanin formation by 50 % at a concentration of $12.23{\pm}0.7{\mu}M$ (1) and $7.83{\pm}0.7{\mu}M$ (2). This result suggests that 7,3',4'-trihydroxyisoflavone from highly aged Doenjang could be used as an active ingredient for cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.41 no.3
• /
• pp.243-252
• /
• 2015

Melanosome, the pigment granule in melanocyte, determines the color of skin when it moves into the keratinocyte. Inhibition of melanosome transfer from melanocyte to keratinocyte results in skin depigmentation. Protease activated receptor-2 (PAR-2) is involved in signal transduction systems via cell membrane and increases the melasome transfer when it is activated by cleavage of their extracellular amino acid sequence by trypsin or by a peptide such as SLIGKV. Here, we showed that lobaric acid inhibited PAR-2 activation and affected the mobilization of $Ca2^+$. The uptake of fluorescent microspheres and isolated melanosomes from melan-a melanocytes to keratinocytes induced by SLIGKV were inhibited by lobaric acid. Also, confocal microscopy studies illustrated a decreased melanosome transfer to keratinocytes in melanocyte-keratinocyte co-culture system by lobaric acid. In addition, lobaric acid induced visible skin lightening effect in human skin tissue culture model, melanoderm$^{(R)}$. Our data suggest that lobaric acid could be an effective skin lightening agent that works via regulation of phagocytic activity of keratinocytes.