AUTHOR=Lyu Ang , Yang Long , Wu Mingde , Zhang Jing , Li Guoqing 

TITLE=High Efficacy of the Volatile Organic Compounds of Streptomyces yanglinensis 3-10 in Suppression of Aspergillus Contamination on Peanut Kernels

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.00142

DOI=10.3389/fmicb.2020.00142

ISSN=1664-302X

ABSTRACT=<p><italic>Aspergillus flavus</italic> and <italic>Aspergillus parasiticus</italic> are saprophytic fungi which can infect and contaminate preharvest and postharvest food/feed with production of aflatoxins (B<sub>1</sub>, B<sub>2</sub>, and G). They are also an opportunistic pathogen causing aspergillosis diseases of animals and humans. In this study, the volatile organic compounds (VOCs) from <italic>Streptomyces yanglinensis</italic> 3-10 were found to be able to inhibit mycelial growth, sporulation, conidial germination, and expression of aflatoxin biosynthesis genes in <italic>A. flavus</italic> and <italic>A. parasiticus in vitro</italic>. On peanut kernels, the VOCs can also reduce the disease severity and inhibit the aflatoxins production by <italic>A. flavus</italic> and <italic>A. parasiticus</italic> under the storage conditions. Scanning electron microscope (SEM) observation showed that high dosage of the VOCs can inhibit conidial germination and colonization by the two species of <italic>Aspergillus</italic> on peanut kernels. The VOCs also showed suppression of mycelial growth on 18 other plant pathogenic fungi and one Oomycetes organism. By using SPME-GC-MS, 19 major VOCs were detected, like in other <italic>Streptomyces</italic>, 2-MIB was found as the main volatile component among the detected VOCs. Three standard chemicals, including methyl 2-methylbutyrate (M2M), 2-phenylethanol (2-PE), and β-caryophyllene (β-CA), showed antifungal activity against <italic>A. flavus</italic> and <italic>A. parasiticus</italic>. Among them, M2M showed highest inhibitory effect than other two standard compounds against conidial germination of <italic>A. flavus</italic> and <italic>A. parasiticus</italic>. To date, this is the first record about the antifungal activity of M2M against <italic>A. flavus</italic> and <italic>A. parasiticus</italic>. The VOCs from <italic>S. yanglinensis</italic> 3-10 did not affect growth of peanut seedlings. In conclusion, our results indicate that <italic>S. yanglinensis</italic> 3-10 may has a potential to become a promising biofumigant in for control of <italic>A. flavus</italic> and <italic>A. parasiticus</italic>.</p>