Characterization of Bacillus amyloliquefaciens DA12 Showing Potent Antifungal Activity against Mycotoxigenic Fusarium Species

• Published in: The plant pathology journal Vol. 33; no. 5; pp. 499 - 507
• Main Authors: Lee, Theresa, Park, Dami, Kim, Kihyun, Lim, Seong Mi, Yu, Nan Hee, Kim, Sosoo, Kim, Hwang-Yong, Jung, Kyu Seok, Jang, Ja Yeong, Park, Jong-Chul, Ham, Hyeonheui, Lee, Soohyung, Hong, Sung Kee, Kim, Jin-Cheol
• Format: Journal Article
• Language: English
• Published: Korea (South) 한국식물병리학회 01.10.2017; Korean Society of Plant Pathology; Hanrimwon Publishing Company
• Subjects: antifungal activity; Bacillus amyloliquefaciens; iturin A; mycotoxin; 농학; mycotoxin; Bacillus amyloliquefaciens; iturin A; antifungal activity
• ISSN: 1598-2254; 2093-9280
• DOI: 10.5423/PPJ.FT.06.2017.0126

In an attempt to develop a biological control agent against mycotoxigenic species, we isolated strain DA12 from soil and explored its antimicrobial activities. DA12 was active against the growth of mycotoxigenic , , , and both and (maize). Further screening using dual culture extended the activity range of strain DA12 against other fungal pathogens including , , , , , and . The butanol extract of the culture filtrate of DA12 highly inhibited the germination of macroconidia with inhibition rate 83% at a concentration of 31.3 μg/ml and 100% at a concentration of 250 μg/ml. The antifungal metabolite from the butanol extract was identified as iturin A by thin layer chromatography-bioautography. In addition, volatile organic compounds produced by DA12 were able to inhibit mycelial growth of various phytopathogenic fungi. The volatile compounds were identified as 2-heptanone, 5-methyl heptanone and 6-methyl heptanone by gas chromatography-mass spectrometry (GC-MS) analysis. These results indicate that the antagonistic activity of DA12 was attributable to iturin A and volatile heptanones, and the strain could be used as a biocontrol agent to reduce the development of diseases and mycotoxin contamination of crops.