Production of Ganodiesel from the biomass of Ganoderma lucidum in air-L-shaped bioreactor (ALSB)

The increasing need for alternative and sustainable energy sources, prompted by the depletion of fossil fuels and the rise in greenhouse gas emissions, has generated attention towards exploring fast-growing filamentous fungi as a potential bioenergy source. This study aimed to optimize Ganoderma lucidum production for elevated biomass and lipid yields in submerged liquid fermentation. The optimization involved varying initial pH, glucose concentration, and agitation rate using response surface methodology (RSM) with central composite design (CCD). Glucose concentration and initial pH significantly influenced biomass production, while agitation rate had an insignificant effect. For lipid production, glucose concentration, initial medium pH, and agitation rate were identified as significant factors. The optimized conditions (initial pH 6, 50 g/L glucose concentration, and 113.42 rpm) were validated in 500 mL shake flasks and a 3 L Air-L-Shaped Bioreactor (ALSB). Shake flask results showed 8.33 g/L of biomass and 2.17 % of lipid, while the ALSB system produced 5.32 g/L of biomass and 2.35 % lipid. The obtained Ganoderma lucidum mycelial lipid underwent acid-catalysed transesterification to produce biodiesel, which was subjected to several tests to comply ASTM and EN standards. This study serves as a valuable reference for future biodiesel applications through the optimization of Ganoderma lucidum biomass and lipid production.