Seasonal and Geographical Impact on the Mycotoxigenicity of <i>Aspergillus</i> and <i>Fusarium</i> Species Isolated from Smallholder Dairy Cattle Feeds and Feedstuffs in Free State and Limpopo Provinces of South Africa
Oluwasola Abayomi Adelusi,
Sefater Gbashi,
Janet Adeyinka Adebo,
Adeola Oluwakemi Aasa,
Oluwaseun Mary Oladeji,
Glory Kah,
Oluwafemi Ayodeji Adebo,
Rumbidzai Changwa,
Patrick Berka Njobeh
Affiliations
Oluwasola Abayomi Adelusi
Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Sefater Gbashi
Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Janet Adeyinka Adebo
Food Evolution Research Laboratory, School of Hospitality and Tourism, College of Business and Economics, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Adeola Oluwakemi Aasa
Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Oluwaseun Mary Oladeji
Department of Biology and Environmental Science, Faculty of Science, Sefako Makgatho Health Sciences University, P.O. Box 139, Pretoria 0204, South Africa
Glory Kah
Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Oluwafemi Ayodeji Adebo
Food Innovation Research Group, Department of Biotechnology and Food Technology, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Rumbidzai Changwa
Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
Patrick Berka Njobeh
Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, P.O. Box 17011, Johannesburg 2028, South Africa
This study evaluated the impact of seasonal and geographical variations on the toxigenicity of Aspergillus and Fusarium strains previously isolated from smallholder dairy cattle feeds and feedstuffs sampled during summer and winter in the Free State and Limpopo provinces of South Africa (SA). In total, 112 potential toxigenic fungal species were obtained and determined for their capability to produce mycotoxins on solid Czapek Yeast Extract Agar (CYA); followed by liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Our result revealed that 41.96% of the fungal species produced their respective mycotoxins, including aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), and zearalenone (ZEN), with higher levels of AFB1 (0.22 to 1045.80 µg/kg) and AFB2 (0.11 to 3.44 µg/kg) produced by fungal species isolated from summer samples than those in winter [(0.69 to 14.44 µg/kg) and (0.21 to 2.26 µg/kg), respectively]. The same pattern was also observed for AFB1 and AFB2 in Limpopo (0.43 to 1045.80 µg/kg and 0.13 to 3.44 µg/kg) and Free State (0.22 to 576.14 µg/kg and 0.11 to 2.82 µg/kg), respectively. More so, ZEN concentrations in summer (7.75 to 97.18 µg/kg) were higher than in winter (5.20 to 15.90 µg/kg). A similar observation was also noted for ZEN in Limpopo (7.80 to 97.18 µg/kg) and Free State (5.20 to 15.90 µg/kg). These findings were confirmed via Welch and Brown-Forsythe tests with significantly (p ≤ 0.05) higher mycotoxin levels produced by fungal strains obtained in samples during summer than those in winter. In contrast, the concentrations of mycotoxins produced by the fungal species from both provinces were not significantly (p > 0.05) different.
