Optimization of liquid fermentation and cytotoxic activity of nucleosides from Sanghuangporus vaninii
ZHU Zixuan1， ZHANG Shihao1， TIAN Xing1， LI Xueyan1， ZOU Kun1，YU Xiaoqin1， LI Xiao1，ZENG Jianhong1， MA Minghua2， WANG Qian3， LIU Chengxiong1， LIU Zhaoxia1
(1.Hubei Key Laboratory of Natural Products Research and Utilization， China Three Gorges University， Yichang 443003， Hubei， China； 2.Forest Fire Prevention Center， Yichang 443000， Hubei， China；3.Yichang Humanwell Pharmaceutical Co.， Ltd， Yichang 443000， Hubei， China)
Abstract：Sanghuangporus vaninii is a valuable medicinal fungus， which contains nucleoside components that can be developed into pharmaceuticals and health products with antiviral， antitumor and antibacterial activities. In this paper， the fermentation conditions and ratio of carbon， nitrogen and inorganic salts for liquid fermentation of Sanghuangporus vaninii were optimized by single factor and orthogonal tests， using nucleoside yield as an indicator. And the effects of adding different precursors and regulatory factor on the yield of nucleoside were investigated. One of the key factors affecting nucleoside production was screened out as exogenous precursors such as hypoxanthine and adenine. The optimal fermentation conditions were determined as follows： 10% inoculum， initial pH 7， incubation temperature 32 ℃， shaker speeds 140 r·min－1 and incubation time 5 d. The optimal medium ratios were as follows： glucose 15.00 g·L－1， sucrose 20.00 g·L－1， peptone 5.00 g·L－1， beef paste 2.50 g·L－1， MgSO4 1.00 g·L－1， CaCl2 1.50 g·L－1， ZnSO4 1.00 g·L－1， MnSO4 0.50 g·L－1. Optimal amount of precursor and regulatory factor were hypoxanthine 1.50 g·L－1， adenine 2.50 g·L－1， sodium pyruvate 3.50 g·L－1 and quercetin 0.25 g·L－1. Under the optimum conditions， the nucleoside yield of liquid fermentation of Sanghuangporus vaninii was 291.16 ± 6.21 mg·L－1， 32.3 times higher than that before optimization. In addition， the cytotoxic activities of the nucleoside enriched products from the fruiting body and sample that before and after optimization were compared. The experimental results showed that the optimized liquid fermentation nucleoside products had the best inhibitory activity on human hepatoma cell line HepG2， with a higher inhibitory rate than the enriched products before optimization and the fruiting body products， This paper provided a theoretical basis for the further development and utilization of Sanghuangporus vaninii.
2023, Vol. 57 
