Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture
This study identified and monitored the levels of aflatoxins (B1 and B2) produced by Aspergillus flavus isolate VKMN22 (OP355447) in maize samples sourced from a local shop in Johannesburg, South Africa. Maize samples underwent controlled incubation after initial rinsing, and isolates were identifie...
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| Format: | Article |
| Language: | English |
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Elsevier
2024-07-01
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| Series: | Food Chemistry: Molecular Sciences |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666566224000042 |
| _version_ | 1797272413371629568 |
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| author | Viola O. Okechukwu Abidemi P. Kappo Patrick B. Njobeh Messai A. Mamo |
| author_facet | Viola O. Okechukwu Abidemi P. Kappo Patrick B. Njobeh Messai A. Mamo |
| author_sort | Viola O. Okechukwu |
| collection | DOAJ |
| description | This study identified and monitored the levels of aflatoxins (B1 and B2) produced by Aspergillus flavus isolate VKMN22 (OP355447) in maize samples sourced from a local shop in Johannesburg, South Africa. Maize samples underwent controlled incubation after initial rinsing, and isolates were identified through morphological and molecular methods. In another experiment, autoclaved maize grains were intentionally re-inoculated with the identified fungal isolate using spore suspension (106 spore/mL), after which 1 g of the contaminated maize sample was inoculated on PDA media and cultured for seven days. The aflatoxin concentrations in the A. flavus contaminated maize inoculated on culture media was monitored over seven weeks and then measured using liquid chromatography–mass spectroscopy (LC-MS). Results confirmed the successful isolation of A. flavus strain VKMN22 with accession number OP355447, which consistently produced higher levels of AFB1 compared to AFB2. AF concentrations increased from week one to five, then declined in week six and seven. AFB1 levels ranged from 594.3 to 9295.33 µg/kg (week 1–5) and then reduced from 5719.67 to 2005 µg/kg in week six and seven), while AFB2 levels ranged from 4.92 to 901.67 µg/kg (weeks 1–5) and then degraded to 184 µg/kg in week six then 55.33 µg/kg (weeks 6–7). Levene's tests confirmed significantly higher mean concentrations of AFB1 compared to AFB2 (p ≤ 0.005). The study emphasizes the importance of consistent biomonitoring for a dynamic understanding of AF contamination, informing accurate prevention and control strategies in agricultural commodities thereby safeguarding food safety. |
| first_indexed | 2024-03-07T14:27:58Z |
| format | Article |
| id | doaj.art-59429aacd5f84fc4abc6e43f8f45ecfc |
| institution | Directory Open Access Journal |
| issn | 2666-5662 |
| language | English |
| last_indexed | 2024-03-07T14:27:58Z |
| publishDate | 2024-07-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Food Chemistry: Molecular Sciences |
| spelling | doaj.art-59429aacd5f84fc4abc6e43f8f45ecfc2024-03-06T05:28:51ZengElsevierFood Chemistry: Molecular Sciences2666-56622024-07-018100197Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar cultureViola O. Okechukwu0Abidemi P. Kappo1Patrick B. Njobeh2Messai A. Mamo3Department of Biochemistry, Auckland Park Kingsway Campus, University of Johannesburg, South AfricaDepartment of Biochemistry, Auckland Park Kingsway Campus, University of Johannesburg, South AfricaDepartment of Food and Biotechnology, PO Box 17011, Doornfontein Campus, University of Johannesburg, South AfricaDepartment of Chemical Sciences, PO Box 2028, Doornfontein Campus, University of Johannesburg, South Africa; Corresponding author.This study identified and monitored the levels of aflatoxins (B1 and B2) produced by Aspergillus flavus isolate VKMN22 (OP355447) in maize samples sourced from a local shop in Johannesburg, South Africa. Maize samples underwent controlled incubation after initial rinsing, and isolates were identified through morphological and molecular methods. In another experiment, autoclaved maize grains were intentionally re-inoculated with the identified fungal isolate using spore suspension (106 spore/mL), after which 1 g of the contaminated maize sample was inoculated on PDA media and cultured for seven days. The aflatoxin concentrations in the A. flavus contaminated maize inoculated on culture media was monitored over seven weeks and then measured using liquid chromatography–mass spectroscopy (LC-MS). Results confirmed the successful isolation of A. flavus strain VKMN22 with accession number OP355447, which consistently produced higher levels of AFB1 compared to AFB2. AF concentrations increased from week one to five, then declined in week six and seven. AFB1 levels ranged from 594.3 to 9295.33 µg/kg (week 1–5) and then reduced from 5719.67 to 2005 µg/kg in week six and seven), while AFB2 levels ranged from 4.92 to 901.67 µg/kg (weeks 1–5) and then degraded to 184 µg/kg in week six then 55.33 µg/kg (weeks 6–7). Levene's tests confirmed significantly higher mean concentrations of AFB1 compared to AFB2 (p ≤ 0.005). The study emphasizes the importance of consistent biomonitoring for a dynamic understanding of AF contamination, informing accurate prevention and control strategies in agricultural commodities thereby safeguarding food safety.http://www.sciencedirect.com/science/article/pii/S2666566224000042A. flavusAflatoxinMaizeMolecular identification, biomonitoringLC-MS |
| spellingShingle | Viola O. Okechukwu Abidemi P. Kappo Patrick B. Njobeh Messai A. Mamo Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture Food Chemistry: Molecular Sciences A. flavus Aflatoxin Maize Molecular identification, biomonitoring LC-MS |
| title | Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture |
| title_full | Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture |
| title_fullStr | Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture |
| title_full_unstemmed | Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture |
| title_short | Morphed aflaxotin concentration produced by Aspergillus flavus strain VKMN22 on maize grains inoculated on agar culture |
| title_sort | morphed aflaxotin concentration produced by aspergillus flavus strain vkmn22 on maize grains inoculated on agar culture |
| topic | A. flavus Aflatoxin Maize Molecular identification, biomonitoring LC-MS |
| url | http://www.sciencedirect.com/science/article/pii/S2666566224000042 |
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