Improvement of ganoderic acid production by fermentation of Ganoderma lucidum with cellulase as an elicitor

•First-time use of cellulase as an elicitor for ganoderic acid production.•Cellulase was effective in enhancing GA production in G. lucidum fermentation.•Ganoderic acid (GA) titer reached 1608.0 mg/l in two-stage cultivation.•GA titer of 1252.7 mg/l was obtained in submerged fermentation of G. lucidum.•GA titer of 1252.7 mg/l was 66% higher than the best reported data.

Two-stage cultivation of Ganoderma lucidum was performed for the enhanced production of ganoderic acid (GA). Cellulase was identified to be an effective elicitor for the improvement of GA production, and GA titer reached 1334.5 mg/l compared to the control (779.6 mg/l) using lactose as the substrate without cellulase addition. Loading of 5 mg/l cellulase on day 3 resulted in the maximal GA titer of 1608 mg/l. To our knowledge, this is the first time that cellulase was used as the elicitor to enhance GA production. Submerged fermentation in a 2.0-l bioreactor was also conducted with cellulase as the elicitor, and as a result the maximal GA titer of 1252.7 mg/l was obtained on day 12. This is so far the best GA production obtained in submerged fermentation of G. lucidum.