Xu Xiangqun, Quan Lili, Shen Mengwei
College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou 310018, China.
College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Int J Biol Macromol. 2015;77:143-50. doi: 10.1016/j.ijbiomac.2015.03.013. Epub 2015 Mar 19.
Polysaccharides are important secondary metabolites from the medicinal mushroom Inonotus obliquus. Various fatty acids, surfactants and organic solvents as cell membrane-reorganizing chemicals were investigated for their stimulatory effects on the growth of fungal mycelium and production of exopolysaccharides (EPS) and endopolysaccharides (IPS) by submerged fermentation of I. obliquus. After evaluation of 14 chemicals, oleic acid, Tween 80, and TritonX-100 were chosen for optimization of addition concentration and addition time. Among the three chemicals, 0.1% (v/v) Tween 80 gave maximum production of mycelial biomass, EPS, IPS1, and IPS2 with a increase of 16.6, 81.6, 37.7 and 18.1%, respectively, when supplemented at the early growth phase (24h after inoculation). These EPS, IPS1, and IPS2 had significantly (p<0.05) stronger scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals than those from the control medium. IPS1 from Tween 80-containing medium was the most effective antioxidant, with an estimated IC50 value of 0.74mg/mL. This might be attributed to that the EPS and IPS from the Tween 80-containing medium had significantly (p<0.05) higher content of sugar and glucose among the six monosaccharide compositions than those from the control. The simultaneously enhanced accumulation of bioactive EPS and IPS of cultured I. obliquus supplemented with Tween 80 was evident.
多糖是药用真菌桦褐孔菌的重要次生代谢产物。研究了各种脂肪酸、表面活性剂和有机溶剂作为细胞膜重组化学物质对桦褐孔菌深层发酵过程中真菌菌丝体生长以及胞外多糖（EPS）和胞内多糖（IPS）产生的刺激作用。在评估了14种化学物质后，选择油酸、吐温80和曲拉通X - 100来优化添加浓度和添加时间。在这三种化学物质中，当在生长早期（接种后24小时）添加0.1%（v/v）的吐温80时，菌丝体生物量、EPS、IPS1和IPS2的产量最高，分别增加了16.6%、81.6%、37.7%和18.1%。这些EPS、IPS1和IPS2对2,2 - 二苯基 - 1 - 苦基肼（DPPH）自由基的清除活性明显（p<0.05）强于对照培养基中的产物。来自含吐温80培养基的IPS1是最有效的抗氧化剂，估计IC50值为0.74mg/mL。这可能归因于含吐温80培养基中的EPS和IPS在六种单糖成分中的糖和葡萄糖含量明显（p<0.05）高于对照。添加吐温80的培养桦褐孔菌中生物活性EPS和IPS的同时积累增强是明显的。
