The Bacteriological Properties of <i>Bacillus</i> Strain TM-I-3 and Analysis of the Volatile Antifungal Compounds Emitted by this Bacteria

Abstract

Previously, we isolated and examined a bacterial strain designated as TM-I-3, belonging to the genus Bacillus, from soil in Nagasaki, Japan. This bacterium was able to inhibit the growth of molds, without coming into direct contact with them. Non-contact antifungals are capable of providing multidirectional inhibition and may contribute to disease prevention. In this study, we revealed the bacteriological properties of TM-I-3 and evaluated the antifungal activity of the compounds emitted from this bacterium. In addition, we analyzed the antimicrobial substances released from TM-I-3 using GC/MS to elucidate the mechanism of its action. Antimicrobial compounds from strain TM-I-3 were identified as acetic acid, propanoic acid, isovaleric acid, 2-methylbutanoic acid, and benzaldehyde, which are all reported to have antimicrobial activity. TM-I-3 demonstrated possible efficacy in inhibiting the growth of Aspergillus fumigatus, Cladosporium cladosporioides and Penicillium expansum, which may lead to inhibition of common fungal contaminants of household products and prevention of some pulmonary diseases.

Inhibition of Fungal Growth and Induction of a Novel Volatilome in Response to Chromobacterium vaccinii Volatile Organic Compounds

“…Based on our comparative analyses of the VOCs from mono-and co-cultures with C. vaccinii MWU328 and MWU328W, we identified four candidate fungistatic VOCs, 1-octanol, CA-18, UNK-27, and HCN, which we presume to be under quorum regulation. More than a dozen alcohols and carboxylic acids have been previously identified as fungistatic or fungicidal (Giorgio et al, 2015;Alijani et al, 2019;Osaki et al, 2019), lending precedence to the putative antifungal VOCs 1-octanol and CA-18, though the link between quorum regulation and antifungal alcohol or carboxylic acid bVOCs has not been established. However, the quorum regulation of antifungal VOCs has been previously demonstrated with acetophenone and 2-aminoacetophenone, quorum-sensing-related molecules produced by Pseudomonas sp.…”

Antibiotic Effects of Volatiles Produced by Bacillus tequilensis XK29 against the Black Spot Disease Caused by Ceratocystis fimbriata in Postharvest Sweet Potato

“…Isovaleric acid and 2-methylbutanoic acid are the main volatile components of Bacillus sp. TM-I-3, whose VOCs can inhibit the growth of Aspergillus fumigatus, Cladosporium cladosporioides, and Penicillium expansum . These two short-chain fatty acids were also the active fractions isolated from the cell-free supernatant of marine bacterium Pseudoalteromonas haloplanktis, which had a wide range of inhibitory activities against marine and clinical pathogenic bacteria .…”

“…TM-I-3, whose VOCs can inhibit the growth of Aspergillus fumigatus, Cladosporium cladosporioides, and Penicillium expansum. 46 These two shortchain fatty acids were also the active fractions isolated from the cell-free supernatant of marine bacterium Pseudoalteromonas haloplanktis, which had a wide range of inhibitory activities against marine and clinical pathogenic bacteria. 47 The addition of branched volatile fatty acids, such as isovaleric, isobutyric, and 2-methylbutanoic acids, to inferior forage can promote the degradation of dietary structural carbohydrates and the growth of rumen fiber degrading bacteria, which are conducive to the digestion of fiber in rumen and the avoidance of feed waste.…”