Study On The Liquid Fermentation Culture Of Inonotus Obliquus And Its Bioactive Substances

Inonotus obliquus is a rare medicinal fungus, in which there are a variety of bioactive substances. Inonotus obliquus have a wide range of development value and application prospects. In this paper, firstly, the corn mediums were applied to Inonotus obliquus for liquid fermentation culture, and we studied its antioxidant activity of liquid fermentation and produced polysaccharide. At the same time, we extracted triterpenoids in the cells by means of ultrasonic. During the reaeasch on antioxidant activity in vitro of extracellular polysaccharide, we measured the total reducing power, superoxide anion scavenging activity and hydroxyl radical scavenging activity. In addition, we conducted orthogonal experiments and response surface experiments on the extraction rate by selecting three factors of ultrasonic temperature, ultrasonic time and solid-liquid ratio on the process of the triterpenoids ultrasonic extraction. Finally, we analysed the biological activity of Inonotus obliquus.On the research of polysaccharide yield, Inonotus obliquus was fermentated and cultured at the conditions of 28 ℃ and 160 r / min for 9 days so that the polysaccharide yield in the broth was 4.65 μg /ml. In terms of the study on the antioxidant activity in vitro of the extracellular polysaccharide, the total reducing power, superoxide anion scavenging activity and hydroxyl radical scavenging activity were measured by means of Prussian blue method,pyrogallol autoxidation and Fenton system, respectively. When the concentration of extracellular polysaccharide reached 250 μg / ml, the absorbance OD700 value of the total reducing power was 0.078. As for the scavenging rate of hydroxyl radical, the extracellular polysaccharide was 20.44%. The scavenging rate of the superoxide anion was 22.05%.In the experiments of triterpenoids extraction, ultrasonic temperature, ultrasonic time and solid-liquid ratio caused greater impact on the extraction rate in the light of the results of single factor experiments.Therefore, we conducted the orthogonal experiments and response surface experiments by selecting these three factors. In the end, we determined the conditions of the ultrasonic extraction. These are the optimal temperature of 52.4 ℃, the optimum time of 20.47 min,solid-liquid ratio of 1: 3 and the extraction rate of 5.22%.The experimental results show that the extracellular polysaccharide in the Inonotus obliquus has antioxidant activity, and we determine the optimum conditions of the triterpenoids extraction in the Inonotus obliquus. These results provide a certain theoretical basis for the applications on the production in a large scale and medical in the industrialization.