In Vitro Inhibition of Melanin Formation and Enhancement of Collagen Production by a Mushroom Sclerotial Water Extract from the Tiger Milk Mushroom, Lignosus rhinocerus (Agaricomycetes), with No Skin and Eye Irritation

Lignosus rhinocerus has bioactive properties, such as anti-inflammatory, antioxidant, antiglycation, and immunomodulatory effects, that are beneficial to the skin. Gas chromatography-mass spectrometry analysis revealed the presence of cosmeceutical compounds, including linoleates, ascorbic acid dipalmitate, and all-trans-squalene, in the mushroom sclerotium. We further investigated the depigmentation and antiaging activities of L. rhinocerus cultivar TM02 sclerotia cold water extract (TM-CWE). TM-CWE at 10% (v/v) inhibited melanin production at the intra- and extracellular levels of B16-F1 melanoma cells (50.6-53.3%) and downregulated microphthalmia-associated transcription factor, the key protein for melanogenic enzyme expression, at the intracellular level (44.5 ± 2.6%). The extract also promoted human procollagen type 1 production in HaCat cells by 51.30 ± 2.87% at 12.5% (v/v). Irritation tests using three-dimensional eye and skin models further indicated that TM-CWE is a nonirritant with > 75% viability. Therefore, L. rhinocerus TM02 demonstrated the capacity to be a beneficial ingredient for skin care application.