Effects of Camellia reticulata, Chloranthus japonicas, Dodonaea viscosa and Paris polyphylla on the proliferation of and tyrosinase activity in a melanocyte cell line

Abstract

Objective To estimate the whitening effect of extracts of Camellia reticulata, Chloranthus japonicas, Dodonaea viscosa and Paris polyphylla. Methods A human epidermal melanocyte cell line HEM-m was cultured in vitro, and classified into several groups to be treated with 7 concentrations（10, 25, 50, 100, 200, 400, 800 mg/L）of different plant extracts, including Camellia reticulata leaf extract, 70% ethanol-eluted fraction of Camellia reticulata leaf extract, extract of Camellia reticulata alabastrum, 70% ethanol-eluted fraction of extract of Camellia reticulata alabastrum, Chloranthus japonicas extract, Dodonaea viscosa extract, and Paris polyphylla extract. At the same time, the negative control group, blank control group and positive control group（treated with 100 mg/L arbutin）were set up. After 72 hours of treatment, MTT assay was performed to detect cell proliferation, and dopa-oxidation assay to estimate tyrosinase activity in melanocytes. Results As far as the inhibitory effect on the proliferation of HEM-m cells was concerned, 400 mg/L Camellia reticulata leaf extract, 70% ethanol-eluted fraction of Camellia reticulata leaf extract at 10-100 mg/L, extract of Camellia reticulata alabastrum at 10-25 mg/L, 70% ethanol-eluted fraction of extract of Camellia reticulata alabastrum at 10 mg/L and Dodonaea viscosa extract at 10-25 mg/L were equivalent to（all P > 0.05）, 800 mg/L Camellia reticulata leaf extract was significantly weaker than（P 0.05）, stronger than 70% ethanol-eluted fraction of extract of Camellia reticulata alabastrum at 10-25 mg/L（P < 0.05）, but weaker than the other concentrations of these plant extracts（P < 0.05 or 0.01）. Conclusion Special concentrations of Camellia reticulate and Dodonaea viscose can inhibit tyrosinase activity. Key words: Plant extracts; Melanocytes; Cell proliferation; Tyrosinase