Effects of Oleic Acid Addition Methods on the Metabolic Flux Distribution of Ganoderic Acids R, S and T's...

Area of Science:

• Biotechnology
• Metabolic Engineering
• Mycology

Background:

• Ganoderma lucidum is a fungus known for producing valuable triterpenes, such as ganoderic acids.
• Optimizing the biosynthesis of ganoderic acids R, S, and T is crucial for their pharmaceutical applications.
• Understanding metabolic flux distribution is key to enhancing secondary metabolite production in fungi.

Purpose of the Study:

• To investigate the impact of oleic acid addition methods on the metabolic flux distribution of ganoderic acid biosynthesis in Ganoderma lucidum.
• To determine the optimal conditions for enhancing the production of ganoderic acids R, S, and T.
• To elucidate the effects of oleic acid on key metabolic pathways involved in ganoderic acid synthesis.

Main Methods:

• Submerged fermentation and static culture of Ganoderma lucidum.
• Addition of filter-sterilized oleic acid during fermentation.
• Metabolic flux analysis to quantify pathway distribution.
• Quantification of ganoderic acids R, S, and T content using analytical techniques.

Main Results:

• Adding filter-sterilized oleic acid significantly benefits the synthesis of ganoderic acids R, S, and T.
• Metabolic fluxes for ganoderic acid synthesis pathways (GAP) increased by up to 97.48%.
• Contents of ganoderic acids R, S, and T were elevated by 3.11, 5.19, and 1.44 times, respectively, compared to controls.
• Enhancement observed in glycolysis (EMP), pentose phosphate (PP), and tricarboxylic acid (TCA) cycles, alongside GAP.
• Reduced accumulation of the by-product mycosterol was noted.

Conclusions:

• Oleic acid addition strengthens overall metabolic flux distribution in Ganoderma lucidum during submerged fermentation-static culture.
• This strategy effectively enhances the biosynthesis of ganoderic acids R, S, and T.
• The findings provide a foundation for improving triterpene production in Ganoderma lucidum fermentation.