Inhibitory Effect of Phlorotannins Isolated from Ecklonia cava on Mushroom Tyrosinase Activity and Melanin Formation in Mouse B16F10 Melanoma Cells

Abstract

In this study, to assess the feasibility of phlorotannins isolated from Ecklonia cava as an inhibitor of melanin formation, we evaluated its inhibitory effects on mushroom tyrosinase and 3-isobutyl-1-methylxanthine (IBMX)-induced melanin formation inhibitory effects in B16F10 melanoma cell. The ethanolic (EtOH) extract and ethyl acetate (EtOAc) soluble fraction obtained from E. cava evidenced a marked inhibitory effect on mushroom tyrosinase at a concentration of 50 μg/mL. Repeated column chromatography of the active EtOAc fraction resulted in the isolation of three phlorotannins. Their structures were elucidated on the basis of spectroscopic techniques [1D and 2D nuclear magnetic resonance (NMR)] and characterized as phloroglucinol (1), dioxinodehydroeckol (2), and 7-phloroeckol (3), respectively. Among the compounds, 7-phloroeckol (3) evidenced more potent tyrosinase inhibitory effect with an IC(50) value of 0.85 μM than arbutin (IC(50) = 243.16 μM) and kojic acid (IC(50) = 40.28 μM), which were used as positive controls. Lineweaver-Burk plots suggest that 7-phloroeckol plays as a noncompetitive inhibitor against tyrosinase. Furthermore, these compounds were evaluated for their inhibitory effects on IBMX-induced melanin formation in B16F10 melanoma cells. Treatment with 7-phloroeckol (6.25-100 μM) resulted in a significant inhibition of melanin production in the melanoma cells. In this study, we suggest that 7-phloroeckol might prove useful as a novel inhibitor of melanin formation in cosmetic applications.

Antioxidant and Antibacterial Activities of Chitosan-Phloroglucinol Conjugate

“…Phloroglucinol is a phytochemical derived from edible brown algae with antioxidant, tyrosinase-inhibiting, cytoprotective and anti-inflammatory activities (Kang et al, 2004(Kang et al, , 2006Heo et al, 2005;Yoon et al, 2009;Kim and Kim, 2010). Previously, we demonstrated conducted and the results were compared to the report by Woo and Je (2013 The phloroglucinol content of the chitosan-phloroglucinol conjugate determined using the Folin-Ciocalteau method was 29.28 ± 0.90 mg phloroglucinol/g chitosan-phloroglucinol conjugate.…”

Applications for Marine Resources in Cosmetics

“…In the skin whitening area, a Chlorella extract proposed by the company Codif would also reduce skin pigmentation by more than 10%. 7-phloroeckol, a phlorotannin derived from E. cava brown seaweed, has been proposed as a skin-whitening agent through its anti-tyrosinase activity [86].…”

The serum/PDGF-dependent "melanogenic" role of the minute level of the oncogenic kinase PAK1 in melanoma cells proven by the highly sensitive kinase assay

“…Melanin content was determined as previously described (11). In brief, B16F10 cells (wild-type or PAK1-specific shRNA transfectants) were plated at a density of 2 × 10 4 cells/well in a 24-well plate.…”