The structural analysis of melanin and its hepatoprotective effect from Lachnum sp.

•The possible structural formula of the intracellular homogeneous melanin of Lachnum YM30 (LIM) was concluded.•LIM could protect the liver and combined treatment group could further reduce the inflammatory effect of the model drug on the mice compared with the single positive drug treatment or the melanin treatment groups.•In this study, we formulated the structural information of LIM from Lachnum YM30 and the mechanism of its protective effect on liver injury, analyzing the relationship between its structure and anti-oxidation, anti-inflammation for the first time, compared to previous studies.•LIM are potential prophylactic agents that can be used to prevent LPS/GalN-induced liver injury and that combination therapy is also a potential treatment for reducing liver injury in the model.