Journal
JOURNAL OF MICROBIOLOGY AND BIOTECHNOLOGY
Volume 26, Issue 8, Pages 1383-1391Publisher
KOREAN SOC MICROBIOLOGY & BIOTECHNOLOGY
DOI: 10.4014/jmb.1603.03040
Keywords
Meloidogyne incognita; nematicidal activity; kojic acid; Aspergillus oryzae
Categories
Funding
- National Institute of Biological Resources (NIBR) - Ministry of Environment (MOE) of the Republic of Korea [NIBR201530201]
Ask authors/readers for more resources
The fungal strain EML-DML3PNa1 isolated from leaf of white dogwood (Cornus alba L.) showed strong nematicidal activity with juvenile mortality of 87.6% at a concentration of 20% fermentation broth filtrate at 3 days after treatment. The active fungal strain was identified as Aspergillus oryzae, which belongs to section Flavi, based on the morphological characteristics and sequence analysis of the ITS rDNA, calmodulin (CaM), and beta-tubulin (BenA) genes. The strain reduced the pH value to 5.62 after 7 days of incubation. Organic acid analysis revealed the presence of citric acid (515.0 mg/kg), malic acid (506.6 mg/kg), and fumaric acid (21.7 mg/kg). The three organic acids showed moderate nematicidal activities, but the mixture of citric acid, malic acid, and fumaric acid did not exhibit the full nematicidal activity of the culture filtrate of EML-DML3PNa1. Bioassay-guided fractionation coupled with 1 H-and 13 C-NMR and EI-MS analyses led to identification of kojic acid as the major nematicidal metabolite. Kojic acid exhibited dose-dependent mortality and inhibited the hatchability of M. incognita, showing EC50 values of 195.2 mu g/ml and 238.3 mu g/ml, respectively, at 72 h post-exposure. These results suggest that A. oryzae EML-DML3PNa1 and kojic acid have potential as a biological control agent against M. incognita.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available