Analysis Of Nutrient Composition And Optimization Of Liquid Culture Conditions

A variety of extracts from a natural medicinal fungus, Inonotus obliquus, have been reported exerting no toxic effects on human body, and many publications indicate they harbor free oxygen radicals scavenging activity and can be used for treating a variety of digestive tract cancers and for reducing hyperglycaemia, preventing AIDS, anti-aging, reducing hyperlipemia, lowing blood pressure, and with the use of which allergies can be improved as well as immunity strengthened.In this study, the fruiting body of wild natural medicinal fungus,I. obliquus, was collected from Greater Khingan Mountains of Heilongjiang province, China. The fungus was isolated and purified from fruiting body and was confirmed to be I. obliquus via morphological observation and molecular identification, and the ITS-rDNA sequence of the strain had been submitted to GenBank with accession number of KC312697(GI:461725870). Then, drying mill processing was conducted on the liquid cultured mycelium and fruiting body, crude polysaccharides content in mycelium with7.43g/100g was significantly higher than that of fruiting body with of2.31g/100g; the monosaccharide constitution of I. obliquus polysaccharides was determined using capillary electrophoresis technology, the results of which showed that fructose, xylose, rhamnose, arabinose, glucose, mannose and galactose all could be detected in both mycelium and fruiting body polysaccharides. Meanwhile, crude protein content in mycelium and fruiting body was determined using Kjeldahl determination, with respective to6.69g/100g and21.08g/100g and subsequently, amino acid analyzer was used to investigate the amino acid profiles of I. obliquus proteins, the fruiting bodies contain14kinds of amino acids, the mycelium contain16of amino acids. Furthermore, the determined results regarding to mineral elements by atomic absorption spectrophotometer revealed that both mycelium and fruiting body had a lot amount of K, Fe, Ca, Zn and Mg, a small amount of Na, Mn and Se, and trace concentrations in As and Pb. Lastly, taking polysaccharide yield and biomass as two indexes, the liquid culture conditions were optimized using single factor gradient method, glucose and peptone were assigned to be the optimum carbon and nitrogen sources respectively, with optimum temperature of27℃, optimum initial pH of7.5and130rpm as optimum speed for shaking culture.