关键词: 甲醛降解, 拟青霉菌, 紫外诱变, 甲醛脱氢酶, 降解率

Abstract:

Paecilomyces variotii CSLG1A, a strain able to degrade formaldehyde, was mutagenized by ultraviolet (UV)
irradiation and the selected mutants were tested for their abilities to degrade formaldehyde. The UV mutagenesis was carried
out by placing the original strain at a distance of 30 cm away from a 15-W UV light lamp for 30 s, yielding a mortality rate
of 88%. The mutant stain F1-23 with significantly increased formaldehyde degradation ability was obtained by two rounds
of screening. The critical formaldehyde concentration degraded by the mutant strain was 7.88 g/L, which was enhanced by
22.2% when compared with that obtain with the original strain. The activity of formaldehyde dehydrogenase produced by
F1-23 was 83.6 U/mg, representing a 23.8% increase over that produced by the original strain. The formaldehyde resistance
and degradation capacity of F1-23 remained substantially unchanged after 5 passages, suggesting good genetic stability. In
summary, the strain F1-23 holds great promise for application in the exploration of formaldehyde biodegradation.

Key words: formaldehyde degradation, Paecilomyces variotii, ultraviolet mutagenesis, formaldehyde dehydrogenase, degradation