ANTIFUNGAL ACTIVITY AND CHARACTERIZATION OF Β-1,3- GLUCANASE FROM BACILLUS TEQUILENSIS ML6

This study aims to investigate the antifungal efficacy and enzymatic attributes of extracellular -1,3-glucanase produced by Bacillus tequilensis ML6, isolated in Thua Thien Hue Province, Vietnam.After growing the ML6 strain for 21 h, we found that the extracellular -1,3glucanase reached its highest activity level at around 2.059 U/mL.In an in vitro experiment, -1,3glucanase applied at a concentration of 0.400 U/mL significantly inhibited the growth of four Colletotrichum pathogens (C.scovillei HUD1, C. fructicola HUCL5, C. siamense HUCL3, and C. scovillei HUCL1), with inhibition rates of 72%, 90%, 95%, and 99%, respectively.In addition, -1,3glucanase from B. tequilensis ML6 demonstrated a notable ability to mitigate anthracnose development induced by Colletotrichum spp. on chilli fruits for an extended duration of up to 144 h following enzyme pretreatment at 2 U/mL.The optimal activity conditions for the enzyme were determined to be 40C and pH 8.0.Thermal and pH stability ranged from 30C to 50C and pH 7.0 to 8.0, respectively.The presence of Fe 3+ at 5 mM significantly increased -1,3-glucanase activity up to 121%.Ions (Cu 2+ , Mn 2+ , Al 3+ , Zn 2+ , and Ca 2+ ) and surfactants (urea, EDTA, Triton X-100, and SDS) had inhibition effects on the enzyme, relative activity ranged from 73-91%.