Abstract

ε-Poly-L-lysine (ε-PL) is a novel food biopreservative with broad antimicrobial activity. To improve the fermentation efficiency of ε-PL, a plasma jet, driven by an active helium atom supplied with atmospheric and room temperature plasma (ARTP) biological breeding system, was used as a new method to generate mutations in Streptomyces albulus. After treating the spores with the ARTP jet, S-(2-aminoethyl)-L-cysteine plus glycine resistant mutants were derived. The plasma jet yielded high total (31.6%) and positive (26.0%) mutation rates on S. albulus and a mutated strain, designated as S. albulus A-29, showed a maximum productivity of 1.59 ± 0.08 mg/ml which was four times as much as that of the wild strain in the same culture condition. After 5-generation culture, the strain, S. albulusA-29 still maintained high productivity. This present study showed that the ARTP plasma jet has a strong mutagenic effect on S. albulus.

Key words: Streptomyces albulus, mutation, atmospheric and room temperature plasma, ε-PL yield