Improvement of 1,3-dihydroxyacetone production from Gluconobacter oxydans by ion beam implantation

Improvement of dihydroxyacetone (DHA) production by mutagenesis of ion beam implantation and medium optimization using response-surface methodology (RSM) were investigated in this work. More than 1000 mutant strains were selected through a mutagenesis method using N(+) ions implantation with a dose of 60 × (2.6 × 10(13)) ions/cm(2) and energy of 10 keV. Several high-yield mutant strains were showed the potent application for DHA production and the genetically stable mutant strain G. oxydans ZJB09113 was selected for optimization of cultivation condition by RSM. The optimal medium for DHA fermentation is composed (in g/L) of yeast extract 4.88, CaCO(3) 2.00, and glycerol 52.86 mL/L (initial pH 4.89). The maximal DHA concentration of 40.0 g/L was achieved after 24 hr of shaken flask fermentation at 30°C with 150 rpm, and 196.3% increase in DHA production in comparison with unoptimized conditions.