Optimization Of The Liquid Fermentation Of Antrodia Cinnamomea

Antrodia cinnamomea belongs to basidiomycotina,aphyllophorales,polypores,genera perennial basidiomycete fungi and grows only on decayed trunk wall of Cinnamomum kanehirae,an endemic tree in Taiwan,China.Nowadays,A.cinnamomea is well known as ruby of the forest due to its multiple therapeutic effects.In normal conditions,it takes two or three years for the fruiting bodies of the fungi to mature.Besides,resources of stout camphor tree are limited in specific area of Taiwan.As a result,the exploitation and utilization of A.cinnamomea has been greatly restricted.In this study,based on the liquid fermentation technology of mycelium,the effects of light cycle,temperature and exogenous vegetable oil on triterpenes and polysaccharides have been investigated and analyzed.The main conclusions are presented as follows.Firstly,in the process of liquid fermentation,the mycelia were treated with different illumination periods and excessive temperatures.The results showed that total triterpenes increased 2.42 times after 2 hours treatment at 12℃ and 1.54 times by 12 hours of light treatment.Secondly,six vegetable oils including corn oil,linseed oil,palm oil,peanut oil,camellia oil and rapeseed oil,on a ratio of 1%,were added respectively in the liquid fermentation medium.All vegetable oils significantly increased the biomass and triterpene content in fermented mycelium.Among them,corn oil showed the best potency,and the biomass and triterpene content were increased to 1.3 times and 3.67 times than that of the control,respectively.Further research was made on the optimization of corn oil for the liquid fermentation.The biomass and triterpene contents were 1.56 times and 4.11 times of the control in the optimal fermentation conditions with 1%oil added at 0 hour,inocula amount was 10%and the fermentation time was 14 days.Lastly,to understand underlying gene expression of different treatments,RNA-Seq was applied to examine the mycelia transcriptome.Mycelia were collected at 12℃temperature treatment,12 hours light treatment,1%corn oil treatment and control group for transcriptome sequencing.It showed that 67,114 and 206 differentially expressed genes were specifically expressed in light,corn oil and temperature treatment,respectively.Furthermore,those differentially expressed genes was analyzed in the KEGG metabolic pathway.The result showed that those genes were significantly enriched in glycolysis/gluconeogenesis,cytochrome P450,propionate metabolism,ubiquinone and other terpene biosynthesis,calcium signaling pathways,lysosomes,oxidative phosphorylation and other metabolic pathways.As a conclusion,those potential metabolic pathways may be related to the exogenous stimulus,which promote the development of fermenting mycelium.