Production of polysaccharide, triterpenoid, and phenolic compounds in antler-type Ganoderma sichuanense grown with fruit peels supplementation in liquid culture

Abstract

Ganoderma sichuanense, a unique antler-type variant of the Ganoderma genus, is renowned for its bioactive compounds, including polysaccharides, triterpenoids, and phenolic compounds, which offer several health benefits. This study aimed to optimize the growth of G. sichuanense and the production of bioactive compounds using different types and concentrations of fruit peels as substrates in both solid and liquid media. The results indicate that durian peel was the most effective for mycelial growth on solid medium, with a maximum observed mycelium growth rate of 9.4 mm/day. In the liquid medium, when using mango, durian, and mangosteen peels as substrates, there was no significant difference in the maximum dry mycelium yield among the three types of fruit peels, ranging from 10.98 to 11.12 g/ L (p ≥ 0.05). In a 21-day liquid culture using various fruit peels, 0.1% (w/v) durian peel exhibited the most significant impact on the production of polysaccharides and phenolic compounds in the dried mycelium, with contents of 74.25 mg/g and 57.26 mg GAE/g, respectively. Employing 0.1% (w/v) durian peel for 21 days resulted in the achievement of 21.52 mg/g of triterpenoids as a secondary metabolite. Therefore, the use of fruit peel as a supplement to grow mushrooms can add value to the production of bioactive compounds by an antler-type variant of the G. sichuanense. This work highlights the benefits of enhancing biotechnological production, promoting sustainable waste management, and utilizing fruit peels, a byproduct of the food industry, for bioactive compound production.