Identification of Water-Soluble Compounds from Cinnamomum kanehirae Hay Promoting the Asexual Sporulation of Antrodia cinnamomea and Optimization of Their Addition Levels in the Culture Medium

In order to determine compounds present in the aqueous extract of Cinnamomum kanehirae Hay (CWE) that promote the asexual sporulation of Antrodia cinnamomea in submerged fermentation. First, CWE was isolated by alcohol precipitation and fractional extraction with different organic solvents. The influence of the obtained fractions on the asexual sporulation of A. cinnamomea was investigated. It was showed that the chloroform (at 30 μg/mL) and ethyl acetate (at 50 μg/mL) extracts of the supernatant after ethanol precipitation of CWE presented remarkable promoting effects on the sporulation of A. cinnamomea, and the effect of LFE was significantly more pronounced than that of YZE, indicating that both LFE and YZE contained compounds that promote the sporulation of A. cinnamomea. Subsequently, liquid chromatography-mass spectrometry (LC-MS) was used to analyze the chemical components of the fractions obtained from CWE, and erythritol was considered as the major component that promotes the sporulation of A. cinnamomea. Finally, the effect of erythritol with a purity of 98% on the fermentation performance of A. cinnamomead was investigated. The result showed that erythritol did significantly promote the sporulation of A. cinnamomea and increased the spore production by 55.17% compared with the control group at the optimal concentration of 1.0 μg/mL. Meanwhile, 1.0 μg/mL erythritol significantly promoted the mycelial growth and synthesis of intracellular polysaccharides (IPS) of A. cinnamomea in submerged fermentation and increased the biomass and the yield of IPS by 18.65% and 260.13%, respectively. However, erythritol had no significant effect on the synthesis of triterpenes in A. cinnamomea.