Enhancement of gibberellic acid production from by mutation breeding and glycerol addition.

Gibberellic acid (GA) is a natural plant growth hormone that has been widely used in agriculture and horticulture. To obtain higher GA producing strains, the method of screening the strains for resistance to simvastatin was used after treatment with nitrosoguanidine (NTG) and gamma rays. The rationale for the strategy was that mutants showing simvastatin resistance were likely to be high GA producers, as their activity of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase is relatively more effective.