The JS7 strain, isolated from an old forest tree, produces extracellular enzymes that decolorize synthetic and natural melanin from human hair. Phylogenetic analysis based on the internal transcribed spacer (ITS) sequence indicated that JS7 belongs to the genus Irpex. The JS7 strain has laccase activity while it lacks manganese and lignin peroxidase activity, which suggests that the JS7 strain melanin decolorization activity originated from laccase. Laccase production from the Irpex sp. JS7 improved three-fold in the presence of veratryl alcohol, compared to without an inducer. The optimum pH and temperature for melanin decolorization were 7.5 and 40 °C, respectively. The crude enzyme half-life at 25 °C was about 100 days, and it had high storage stability. The melanin decolorization reaction rate by the crude enzyme conformed to typical enzyme kinetic principles. In the presence of syringaldehyde as a redox mediator, the melanin decolorization rate was 75% within 5 days, similar to the decolorization percentage obtained using the enzyme alone. Based on these results, the Irpex sp. JS7 enzyme is suitable for use in melanin decolorization by whitening agents in the cosmetics industry.

JS7 菌株是从一棵古老的森林树木中分离出来的，它产生的细胞外酶可以使人类头发中的合成和天然黑色素脱色。基于内部转录间隔（ITS）序列的系统发育分析表明JS7属于Irpex属。JS7菌株具有漆酶活性而缺乏锰和木质素过氧化物酶活性，提示JS7菌株黑色素脱色活性来源于漆酶。来自Irpex的漆酶生产sp。与没有诱导剂相比，JS7 在藜芦醇存在下提高了三倍。黑色素脱色的最佳 pH 值和温度分别为 7.5 和 40 ℃。粗酶25℃半衰期约为100天，贮藏稳定性高。粗酶对黑色素的脱色反应速率符合典型的酶动力学原理。在丁香醛作为氧化还原介质存在的情况下，5 天内黑色素脱色率为 75%，与单独使用酶获得的脱色率相似。基于这些结果，Irpex sp。JS7酶适用于化妆品行业美白剂的黑色素脱色。