Effects Of Gastrodiazepines Such As P-hydroxybenzaldehyde On The Metabolism Of Grifola Frondosa Polysaccharides And Its Mechanism

This article is mainly study the effect of main ingredients of Rhizoma gastrodiae(R.gastrodiae) on metabolic mechanism of exopolysaccharides(EPS) by submerged culture of Grifola frondsa(G. frondsa). Firstly, R. gastrodiae extracts were added into the fermentation system of G. frondsa to probe and analyze the effect of additives on biomass(BIO) and EPS productions. Secondly, use the method of High Performance Liquid Chromatography(HPLC) to determine the contents of gastrodine(GA),p-hydroxybenzyl alcohol(HA) and p-hydroxylbenzaldehyde(HBA) of R. gastrodiae ethanol extracts. And then, to find out the main ingredients of R. gastrodiae which one is the most responsible to accelerate BIO and EPS productions, the main ingredients of R. gastrodiae including pure GA and HA as well as HBA were supplemented into the submerged culture of G. frondosa. Finally, the dynamic changes of BIO, EPS and related key enzymes activity were measured during the fermentation period of G.frondsa to discuss and clarify the mechanism that the main ingredients of R.gastrodiae promote EPS biosynthesis from the perspective of enzymology. The main conclusions of this research as follows:Various concentrations of 75% ethanol extract of R. gastrodiae were supplemented into the fermentation system of G. frondsa, and the results showed that the addition of R. gastrodiae ethanol extracts with concentrations ranging from 3 to 9 g/L could significantly promote cell growth and enhance EPS productions(P < 0.05). Among them, 7 g/L R. gastrodiae ethanol extracts gave the best results, where the BIO and EPS productions reached 1.366 and 2.169 g/L, and increased by 78.54% and 142.83%compared with the control(without additives), respectively.R. gastrodiae powder was extracted respectively by ultrasonic wave and room temperature with different volume fraction of ethanol, and the contents of GA, HA and HBA in obtained R. gastrodiae ethanol extracts were determined by the method of HPLC. The results showed that under the extraction conditions for 48 h at room temperature, the sterilized 75% ethanol extract of R. gastrodiae had the best extraction efficiency for the three ingredients measured, and its contents of GA, HAand HBA were: 5.4660?0.8317?1.5913(mg/g), respectively.According to the content of 7g 75% R. gastrodiae ethanol extracts which was extracted for 48 h at room temperature. Various concentrations of GA and HA as well as HBA were added into the fermentation system of G. frondsa, and the result showed that all of the additives including pure GA and HA as well as HBA with proper concentration had an effective stimulatory effect on mycelial growth and EPS biosynthesis. Among them, the addition of HBA at 0.15 g/L exhibited the best results,and the EPS productions reached 2.251 g/L, with an increase of 45.03% compared with the control. Consequently, HBA is the most responsible ingredients to promote the EPS productions in submerged culture of G. frondosa.Comparative analysis the promoting effect of 0.15 g/L HBA and 7 g/L R.gastrodiae ethanol extracts on increasing BIO and EPS productions, and found that the HBA was slightly lower than the ethanol extracts of the R. gastrodiae.Furthermore, the BIO and EPS productions of HBA were slightly lower than the ethanol extracts of the R. gastrodiae during the whole fermentation process of G.frondosa.Dynamic measurement for the changes of BIO and EPS productions, p H value,reducing sugar content and HBA content during the fermentation period of G. frondsa found that G. frondsa can make full use of nutrients(glucose) and active ingredients of R. gastrodiae(HBA) to promote their own growth and EPS biosynthesis. Cell growth was into the adjustment period in 1 to5 days, G. frondsa mainly utilize glucose and other nutrients as well as active ingredients of R. gastrodiae(HBA) to promote its growth. G. frondsa growth was into the logarithmic period in 5 to 9 days, and cells grow rapidly and produce a large number of EPS. In the fermentation of 9 to 13 days,G. frondsa growth reached to a saturation state and it couldn't produce EPS.The measured five key enzymes related EPS biosynthes all exerted high enzyme activity with the addition of HBA at 0.15 g/L and the ethanol extract of R. gastrodiae at7 g/L in submerged culture of G. frondsa, and showed the maximum enzyme activity on the 7th day. In addition, only d TDP-rhamnose biosynthetic enzyme of HBA group is higher than R. gastrodiae ethanol extracts group, other enzymesactivity including ?-phosphoglucomutase, UDP-glucose pyrophosphorylase,UDP-glucose dehydrogenase and d TDP-glucose pyrophosphorylase of R. gastrodiae ethanol extracts group were higher than HBA group and the control group.Consequently, HBA and the ethanol extract of R. gastrodiae can promote cell growth and enhance EPS biosynthesis mainly by increasing the five key enzymes activity.This research has discussed and clarified the mechanism that the main ingredients of R. gastrodiae promote EPS biosynthesis from the perspective of enzymology and obtained the key enzymes related EPS biosynthesis, which may provide beneficial basis to further research this mechanism from the level of gene.