Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i>
Background: Meju is a base material for making soy sauce, soybean paste, and red chili pepper paste, which are representative ingredients of Korean cuisine. Objectives: This study aimed to isolate a predominant bacterial strain of <i>B. subtilis</i> from meju and to observe its inhibitor...
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MDPI AG
2024-02-01
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| Series: | Applied Microbiology |
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| Online Access: | https://www.mdpi.com/2673-8007/4/1/24 |
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| author | Jong-Gyu Kim Jeong-Yeong Park |
| author_facet | Jong-Gyu Kim Jeong-Yeong Park |
| author_sort | Jong-Gyu Kim |
| collection | DOAJ |
| description | Background: Meju is a base material for making soy sauce, soybean paste, and red chili pepper paste, which are representative ingredients of Korean cuisine. Objectives: This study aimed to isolate a predominant bacterial strain of <i>B. subtilis</i> from meju and to observe its inhibitory effects on an aflatoxigenic mold. Methods: We used yellow soybeans (<i>Glycine max (L.) Merr.</i>) grown in South Korea, and meju was produced according to the recommended methods of the Korea Food Research Institute. The identification of the strain was conducted based on its morphological and biochemical characteristics and 16S rDNA sequence. Evaluation of the bacterial effect against <i>A. parasiticus</i> ATCC 15517 was done in yeast extract–sucrose broth at 28 °C. Its inhibitory effect was evaluated using two approaches: mycelial weight and aflatoxin production. Aflatoxins were determined using high-performance liquid chromatography. Results: In the meju samples fermented for three months, a <i>B. subtilis</i> strain, K-0924 was identified. At the end of the incubation period of <i>A. parasiticus</i>, dry mycelial weight was significantly reduced by more than 80% (<i>p</i> < 0.01) and total aflatoxin production was inhibited by more than 63% (<i>p</i> < 0.05) in the presence of <i>B. subtilis</i>. Conclusions: These results indicate that <i>B. subtilis</i> K-0924 inhibits the growth and aflatoxin production of toxigenic <i>Aspergillus</i>, which can be contaminated with meju. We could expect more inhibition by other bacteria related to fermentation of meju, and further examination is necessary on species other than <i>B. subtilis</i>. |
| first_indexed | 2024-04-24T18:35:44Z |
| format | Article |
| id | doaj.art-821efdb589414cd588dd33fcdbea8970 |
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| issn | 2673-8007 |
| language | English |
| last_indexed | 2024-04-24T18:35:44Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Microbiology |
| spelling | doaj.art-821efdb589414cd588dd33fcdbea89702024-03-27T13:18:58ZengMDPI AGApplied Microbiology2673-80072024-02-014135436310.3390/applmicrobiol4010024Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i>Jong-Gyu Kim0Jeong-Yeong Park1Department of Public Health, College of Natural Sciences, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 42601, Republic of KoreaDepartment of Public Health, College of Natural Sciences, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 42601, Republic of KoreaBackground: Meju is a base material for making soy sauce, soybean paste, and red chili pepper paste, which are representative ingredients of Korean cuisine. Objectives: This study aimed to isolate a predominant bacterial strain of <i>B. subtilis</i> from meju and to observe its inhibitory effects on an aflatoxigenic mold. Methods: We used yellow soybeans (<i>Glycine max (L.) Merr.</i>) grown in South Korea, and meju was produced according to the recommended methods of the Korea Food Research Institute. The identification of the strain was conducted based on its morphological and biochemical characteristics and 16S rDNA sequence. Evaluation of the bacterial effect against <i>A. parasiticus</i> ATCC 15517 was done in yeast extract–sucrose broth at 28 °C. Its inhibitory effect was evaluated using two approaches: mycelial weight and aflatoxin production. Aflatoxins were determined using high-performance liquid chromatography. Results: In the meju samples fermented for three months, a <i>B. subtilis</i> strain, K-0924 was identified. At the end of the incubation period of <i>A. parasiticus</i>, dry mycelial weight was significantly reduced by more than 80% (<i>p</i> < 0.01) and total aflatoxin production was inhibited by more than 63% (<i>p</i> < 0.05) in the presence of <i>B. subtilis</i>. Conclusions: These results indicate that <i>B. subtilis</i> K-0924 inhibits the growth and aflatoxin production of toxigenic <i>Aspergillus</i>, which can be contaminated with meju. We could expect more inhibition by other bacteria related to fermentation of meju, and further examination is necessary on species other than <i>B. subtilis</i>.https://www.mdpi.com/2673-8007/4/1/24<i>Bacillus</i> species<i>B. subtilis</i>meju (fermented soybean brick)<i>Aspergillus parasiticus</i> |
| spellingShingle | Jong-Gyu Kim Jeong-Yeong Park Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i> Applied Microbiology <i>Bacillus</i> species <i>B. subtilis</i> meju (fermented soybean brick) <i>Aspergillus parasiticus</i> |
| title | Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i> |
| title_full | Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i> |
| title_fullStr | Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i> |
| title_full_unstemmed | Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i> |
| title_short | Inhibitory Effects of <i>Bacillus subtilis</i> Isolated from Meju (Fermented Soybean Brick) on the Growth of <i>Aspergillus parasiticus</i> |
| title_sort | inhibitory effects of i bacillus subtilis i isolated from meju fermented soybean brick on the growth of i aspergillus parasiticus i |
| topic | <i>Bacillus</i> species <i>B. subtilis</i> meju (fermented soybean brick) <i>Aspergillus parasiticus</i> |
| url | https://www.mdpi.com/2673-8007/4/1/24 |
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