Fig. 1: Effects of different PGRs on triterpenoid biosynthesis and mycelial growth at different concentrations under S. lonicericola fermentation.

a–c The triterpenoid yield, biomass, and triterpenoid production under PBZ, NAA, IAA, and 6-BA induction. Non-treatment and solvent (DMSO) were used as the Mock and CK, respectively. The values with error bars are the means ± SD (n = 3, independent experiments), and the statistical analysis was performed by Duncan’s multiple range test. “ns” indicates no statistically significant differences between groups (P > 0.05). Different letters indicate significant differences between groups (PBZ, NAA, IAA, and 6-BA) (P < 0.05). Asterisks denote significant differences against the CK of the within group: *P < 0.05, **P < 0.01, and ***P < 0.001.