Title: | Efficacy of volatile compounds from Streptomyces philanthi RL-1-178 as a biofumigant for controlling growth and aflatoxin production of the two aflatoxin-producing fungi on stored soybean seeds |
Address: | "College of Innovation and Management, Songkhla Rajabhat University, Songkhla, Thailand. Research and Development Office, Prince of Songkla University, Songkhla, Thailand" |
ISSN/ISBN: | 1365-2672 (Electronic) 1364-5072 (Linking) |
Abstract: | "AIMS: This study aimed to apply the volatile organic compounds from Streptomyces philanthi RL-1-178 (VOCs RL-1-178) as a fumigant to protect soybean seeds against the two aflatoxin-producing fungi in stored soybean seeds. METHODS AND RESULTS: The antifungal bioassay tests on potato dextrose agar (PDA) dishes showed that 30 g l(-1) wheat seed inoculum of S. philanthi RL-1-178 exhibited total (100%) inhibition on Aspergillus parasiticus TISTR 3276 and Aspergillus flavus PSRDC-4. Identification of the VOCs RL-1-178 using GC-MS revealed 39 compounds with the most abundant substances being geosmin (13.75%) followed by l-linalool (13.55%), 2-mercaptoethanol (9.71%) and heneicosane (5.96%). Comparison on the efficacy of the VOCs RL-1-178 (at 30 g l(-1) wheat seed culture) and their four major components (100 microl l(-1) each) on the suppression of the two aflatoxin-producing fungi on PDA plates revealed that the VOCs RL-1-178 as well as geosmin, l-linalool and 2-mercaptoethanol completely inhibited (100%) mycelial growth while heneicosane showed only 70.7% inhibition. Use of the VOCs RL-1-178 (30 g l(-1) ) as a biofumigant on stored soybean seeds resulted in complete protection (100%) against the infection as well as complete inhibition on production of aflatoxin (B(1) , B(2) and G(2) ) (analysed by HPLC) by the two aflatoxin-producing fungi. CONCLUSIONS: The VOCs RL-1-178 displayed strong inhibitory effects on A. parasiticus TISTR 3276 and A. flavus PSRDC-4 as well as inhibited aflatoxin (B(1) , B(2) and G(2) ) production. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings suggest that the VOCs RL-1-178 can be applied as a biofumigant to control the two aflatoxin-producing fungi on stored seeds products" |
Keywords: | "Aflatoxins/biosynthesis Antifungal Agents/metabolism/pharmacology Aspergillus/*drug effects/growth & development/metabolism Fumigation/*methods Pest Control, Biological/*methods Seeds/microbiology Soybeans/*microbiology Streptomyces/*metabolism Streptomyc;" |
Notes: | "MedlineBoukaew, S Prasertsan, P eng RTA 6080010/Thailand Research Fund/ England 2020/03/21 J Appl Microbiol. 2020 Sep; 129(3):652-664. doi: 10.1111/jam.14643. Epub 2020 Apr 8" |