Effects of Lycium barbarum extract on production and immunomodulatory activity of the extracellular polysaccharopeptides from submerged fermentation culture of Coriolus versicolor

Polysaccharopeptides (PSPs) from Coriolus versicolor have been used as immunomodulatory and anticancer agents. However, most studies have concentrated on the mycelial PSPs and not those in the fermented broth. On the other hand, Lycium barbarum fruit has been used as a traditional Chinese herbal medicine for two millennia. Its extract contains various nutrients, minerals, and also polysaccharide–protein complexes, which are proven to be bioactive. Herein we report the effects of L. barbarum fruit extract on the mycelial growth and extracellular PSP (ePSP) production of C. versicolor LH1 by using a submerged fermentation process in 20 l fermenters. Fermentation production of C. versicolor biomass and its ePSP were augmented in the presence of L. barbarum extract. The ePSP such obtained differs from those obtained with normal culture medium in terms of simple sugar composition and protein content but shows similar overall chemical structures as analyzed by Fourier transformed infrared spectroscopy. Moreover, the ePSP from C. versicolor cultured with supplementary L. barbarum extract exhibits significant immunomodulatory activity as judged by its effects on the production of nitric oxide and several cytokines by murine RAW264.7 macrophages.