In this study, potential bioactive compounds in the products of the solid fermentation of the paper mulberry tree bark (Broussonetia papyrifera) with a white rot fungus (Perenniporia tephropora) were investigated. Fractionation of methanolic extracts from the fermented products of the bark led to the isolation of 10 known compounds, namely broussonin B (1), broussonin A (2), 7,4'-dihydroxy-3'-prenylflavan (3), cathayanon H (4), broussoflavonol B (5), isoliquiritigenin (6), broussochalcone B (7), glyasperin A (8), marmesin (9), and vomifoliol (10). Their structures were determined by spectroscopic analysis (including considerations of MS, ¹H, ¹³C NMR, COSY, HMQC, and HMBC spectra) and compared with structures that had been published in the literature. Of these compounds identified, cathayanon H (4) and glyasperin A (8) were isolated for the first time from the paper mulberry tree. Vomifoliol (10) was produced from the bark only after fermentation with white rot fungi. It was observed that concentrations of marmesin (9) and vomifoliol (10) generally increased with an increase in fermentation time, whereas concentration of compounds 1‒8 in the fermented products decreased during the same period. Biological tests showed that the tyrosinase inhibitory activity of marmesin (9) (IC₅₀ = 168.0 μM) was similar to that of arbutin, a well-known tyrosinase inhibitor, whereas vomifoliol (10) exhibited no tyrosinase inhibition activity at any concentration higher than 2 mM. Accordingly, both solids and the liquid broth left after fermentation of the paper mulberry tree bark with the aforementioned white rot fungus could be developed for potential use in industrial applications.

在这项研究中，研究了纸桑树皮（Broussonetia papyrifera）与白腐真菌（Perenniporia tephropora）的固体发酵产物中潜在的生物活性化合物。从树皮发酵产物中分离甲醇提取物，导致分离出10种已知化合物，即布鲁索菌素B（1），布鲁索菌素A（2），7,4'-二羟基-3'-异戊烯基黄烷（3），矢车菊H （4），布鲁索黄酮B（5），异黄体生成素（6），布鲁索卡尔康B（7），甘油G（3），甘油（3），marmesin（9）和伏米泊洛（（10）。通过光谱分析（包括考虑的MS，¹ H，¹³ C NMR，COSY，HMQC和HMBC光谱）确定其结构，并与文献中已发表的结构进行比较。在鉴定出的这些化合物中，首次从纸桑树中分离出cathayanon H（4）和glyasperin A（8）。仅在与白腐真菌发酵后，才从树皮中产生沃米福尔（10）。据观察，marmesin（浓度9）和vomifoliol（10）通常与增加发酵时间的增加，而化合物的浓度1 - 8发酵产品中的维生素在同一时期下降。生物学测试表明，marmesin（9）（IC ₅₀ = 168.0μM ）的酪氨酸酶抑制活性与众所周知的酪氨酸酶抑制剂熊果苷相似，而voomifoliol（10）在任何高于2的浓度下都没有酪氨酸酶抑制活性。毫米 因此，可以开发出将纸桑树皮与上述白腐真菌一起发酵后残留的固体和液体肉汤，以用于工业应用。