Enhanced production of polysaccharides and triterpenoids in Ganoderma lucidum fruit bodies on induction with signal transduction during the fruiting stage

Abstract

Ganoderma lucidum is a medicinal mushroom that has been widely used in East Asia for the treatment of various diseases. The pharmacological activity of this fungus is primarily attributable to the polysaccharides and triterpenoids. In this study, to obtain the fruit bodies with improved content of active constituents, we examined the effect of salicylic acid (SA) and calcium ion on the biosynthesis of polysaccharides and triterpenoids by spraying the chemicals during the fruiting. To explore the underlying mechanisms for the variation, the transcripts of related genes involved in the polysaccharide and triterpenoid biosynthesis were measured. Results showed that Ca2+ had no effect on production of polysaccharides and triterpenoids, whereas SA increased triterpenoid content by 23.32%, compared to the control, but it had little influence on polysaccharide production. Interestingly, the combined induction increased polysaccharide and triterpenoid content by 9.02% and 13.61%, respectively, compared to the control. Under Ca2+ induction, the transcript of ugp gene in the polysaccharide biosynthetic pathway up-regulated in all three stages (mycelium, primordium, and fruit body), while pgm and gls gave no response in the mycelium and primordium stages, and up-regulated in the fruit body stage. Differently, six key triterpenoid biosynthetic genes including hmgr, hmgs, mvd, fps, sqs, and ls did not respond to the induction. In the case of SA and combined induction, pgm and ugp were up-regulated in all three stages, while gls showed an increased expression in the primordium stage and no response in other stages. The six triterpenoid biosynthetic genes were up-regulated in all three stages. The present study provides a useful approach to producing G. lucidum fruit bodies with high polysaccharide and triterpenoid content. This is important to the G. lucidum industry.

Response of Bioactive Metabolite and Biosynthesis Related Genes to Methyl Jasmonate Elicitation in Codonopsis pilosula

“…pilosula by MeJA elicitation. CpMVK, CpMVD, CpDXS, and CpispS are enzymes belonging to the mevalonate pathway, which is one of the branches of terpenoid biosynthesis [52]. Less obvious changes were found in the expression of the CpMVK, CpDXS , and CpispS genes at 24 h after treatment in the adventitious roots and multiple shoots, which might indicate that these genes did not respond to MeJA, as well as CpAXS and CpRHM involved in the carbohydrate biosynthesis.…”

Enhanced Ganoderic Acids Accumulation and Transcriptional Responses of Biosynthetic Genes in Ganoderma lucidum Fruiting Bodies by Elicitation Supplementation

“…A recent study found that spraying SA during the fruiting body formation enhanced the accumulation of GAs. SA increased the triterpenoid content by 23.32% compared to the control [32]. In this study, sodium acetate was more effective (28.63%) at inducing the accumulation of GAs in the fruiting body of G. lucidum .…”

Homologous Overexpression of Genes in Cordyceps militaris Improves the Production of Polysaccharide

“…The crude EPS was precipitated by addition of four volumes of absolute ethanol and stored at 4 °C overnight. After centrifugation at 13000 g for 15 min, the precipitate was suspended in 1 M NaOH at 60 °C for 1 h. Phenol-sulfuric acid method was used for the determination of EPS in the supernatant [37].…”