Stimultaneously Stimulated Production And Antioxidant Activity Of Expolysaccharides And Endopolvsaccharides Of Inonotus Obliauus In Submerged Fermentation

Inonotus obliquus (I. obliquus) is well known as one of the most popularmedicinal species for its therapeutic effect, belonging to the family Hymenochaetaceaof Basidiomycetes, habiting as a parasitism on birches in the cold latitudes（45°N-50°N）of Europe, Asia, and America. According to the studies, many, if notall, higher Basidiomycetes mushrooms contain biologically active polysaccharides infruit bodies, cultured mycelium, and cultured broth. I. obliquus polysaccharides (PS)exhibits great biological activities including immunomodulation, antitumor,antioxidant, and anti-inflammation, on the other hand, has no poisonous effect onhumans. Because there is a great need to supply the market and the solid culture ofmushroom needs to take long time to complete a fruiting body, investigators haverecently exerted their efforts to prepare the mushroom from submerged culture formeeting the increasing consumption demand.Reports in the literature suggested that the production of mushroom secondarymetabolites by submerged fermentation was subjected to the growth environment,including nitrogen source, carbon source, PH and temperature. Hence, manyinvestigates have been conducted on the optimisation of submerged culture conditions.In this studies, various stimulatory agents which were presumed to increase cellpermeability by reorganizing the cell membrane and/or directly affecting synthesis ofenzymes involved in the formation of target products, including plant oils, fatty acids,organic solvents and surfactants, were investigated for their stimulatory effects on thegrowth of fungal mycelium and production of exopolysaccharides (EPS) andendopolysaccharides (IPS) by submerged fermentation of I.obliquus. Then the mosteffective stimulatory agents were chosen for optimisation of addition concentrationand addition time. And the effect of the most effective stimulatory agents on thephysicochemical characteristics and antioxidant activity of EPS and IPS wasinvestigated. In the study, we added lignocellulose (straw) as a following carbonsource to the liquid submerged fermentation so as to get more EPS of I. obliquus.The experimental results are as follows: 1. Among the three chemicals,0.1%(v/v) oleic acid,stearic acid and palmitic acidgave obvious production of mycelial biomass with a increase of13.81%,26.97%and13.24%(p<0.05), respectively. In constrat, linoleic oil, CHAPS and TritonX-100hadthe obvious inhibitory effect on the mycelium biomass. The fatty acid and surfactants(except PEG4000) showed great effect on the production of EPS, among of them,oleic acid, Tween80and TritonX-100gave the maximum production of EPS with aincrease of16.02%,42.66%and42.86%(p<0.05). Compared to IPS (IPS1and IPS2)of the basal medium, the comlex culture which with Tween80, TritonX-100,ethanoland chloroform were incraese by7.12%、6.08%、9.67%、16.87%and20.27%、14.50%、15.20%、17.22%, respectively (p<0.05).2. After evaluation of14chemicals on the growth of fungal mycelium and productionof EPS and IPS by submerged fermentation of I. obliquus., oleic acid, Tween80, andTritonX-100were chosen for optimisation of addition concentration and addition time.The results of research showed that the addition of0.5%(v/v) oleic acid on the1stdaycould promote the mycelium and EPS production, and the best concentration to IPS is0.1%(v/v).0.1%(v/v) Tween80gave maximum production of mycelial biomass, EPS,IPS1, and IPS2with a increase of16.6,81.6,37.7and18.1%(p<0.05), respectively,when supplemented at the early growth phase (24h after inoculation). The addition ofTritonX-100on1stday at the concentration of0.1%(v/v),the effect of EPSproduction was the maximum, and when0.05%(v/v) TritonX-100was added on0day could promote the IPS production.3. The surfactants were added to the lignocellulose (wheat straw) medium to explorethe influence on mycelium growth, the production of EPS and IPS. The experimentalresults showed that the production of mycelium, EPS and IPS from wheat strawheatstraww and TrintonX-100medium increased obviously by30.11%,64.29%,13.49%and23.19%compared with the control cultrure, respectively. And the EPS, IPS1andIPS2from the wheat straw and TrintonX-100medium were higher than those fromthe wheat straw medium. The promote rate were28.16%,7.69%and10.12%(p<0.05),respectively.4. The EPS, IPS1, and IPS2from oleic oil, Tween80and TritonX-100-containing medium, respectively, had significantly (p<0.05) stronger scavenging activity against2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals than those from the control medium.The polysaccharides of I. obliquus were maily composed of glucose, mannose,galactose and a small amount of xylose, arabinose and rhamnose. IPS1from oleicoil-containing medium was the most effective antioxidant, with an estimated IC50value of0.66mg/mL.