CHARACTERIZATION OF ANTIVIRAL WATER-SOLUBLE LIGNIN FROM BAGASSE DEGRADED BY LENTINUS-EDODES

Antiviral water-soluble lignin complex (WSLC) was obtained by purifica tion of extracts from the bagasse culture medium of Lentinus edodes. W SLC contained 80% of water-soluble lignin (WSL), 20% of carbohydrates and 1-2% of proteins, but the antiviral activity was demonstrated to b e derived from the WSL moiety. We used WSLC to analyze the structure o f WSL in detail in comparison with that of native bagasse milled wood lignin (MWL). The result of nitrobenzene oxidation revealed that the t otal yield of benzaldehydes originating from WSL was much lower than t hat from MWL, which suggests that the structure of native bagasse lign in is heavily modified during the decay process. The potassium permang anate oxidation yielded more condensed type products from WSL than fro m MWL. However, the total yields of aromatic acids from WSL were obvio usly lower than those from MWL. Furthermore, the methoxyl content of W SL was lower than that of MWL. Thus, our results showed that the quant ities of benzene rings in WSL were obviously reduced. The decrease in amounts of aromatic moieties in WSL suggests that native aromatic ring structures of bagasse lignin were modified by ring opening or formati on of quinone moieties during the degradation of bagasse lignin by Len tinus edodes.