Molecular Characterization of Fungi Producing Aflatoxin in Vigna subterranean (Bambara Groundnut) sold in Three Selected Markets in Enugu Metropolis
| dc.contributor.author | Victoria Chiyaka, IWU | |
| dc.date.accessioned | 2024-05-21T14:05:12Z | |
| dc.date.available | 2024-05-21T14:05:12Z | |
| dc.date.issued | 2022-12 | |
| dc.description.abstract | Humans require nutritious food to maintain a healthy diet. Toxic strains of Aspergillus species produces aflatoxins, which are carcinogenic in nature. Bambara groundnut (BG), Vigna subterranea is an underutilized crop used for a variety of delicacies. Consumption of food contaminated with aflatoxin (> 20 ppb) has been linked to death. The aim of this study is to identify the aflatoxin producing fungi in BG using Molecular method. Samples were purchased at five points from three selected markets: Abakpa; New main and Ogbete markets in Enugu Metropolis and transported in sterile polythene bags to the laboratory. Direct plating on Saboraud Dextrose Agar (SDA) with chloramphenicol to suppress bacterial growth was used to isolate fungus from BG samples. The plates were kept at room temperature for 48-72 hours before being examined. Repeated sub-culturing was used to create pure fungus cultures. Aflatoxin quantification of the BG samples was carried out, after which aflatoxigenic analysis of the isolates was conducted using molecular techniques. A total of seventy-seven fungi were isolated. The percentage frequency of occurrence includes Aspergillus flavus (32%), Culvulanaria (30%), Aspergillus niger (12%), Aspergillus fumigatus (6%), Penicillum spp. (5%), Colletotrichum spp. (4%), Rhizopus stolonifer (3%), Aspergillus orchaceous (3%) and Trichotothecium spp. (3%), Alternaria macrospora and Scolecosporae (1% each). The aflatoxin analysis showed that the samples from the three markets were contaminated with aflatoxin above the permissible dosage of 20 ppb, with the least been 69 ppb (Abakpa) and the highest been 80 ppb (Ogbete). 25 isolates were sequenced from which 14 were identified as Aspergillus flavus and screened for aflatoxigencity. All 14 isolates were positive for aflatoxin regulatory gene. The study showed that the BG samples were contaminated with aflatoxin which made them unsafe for human consumption, hence there is need to enhance the knowledge of risk associated with the consumption of BG. Keywords: Bambara groundnut, aflatoxin, PCR, Aspergillus, BLAST Word Count: 300 | |
| dc.identifier.citation | Kate Turabian | |
| dc.identifier.other | M.Sc | |
| dc.identifier.uri | https://repository.lcu.edu.ng/handle/123456789/229 | |
| dc.language.iso | en | |
| dc.publisher | Lead City University | |
| dc.relation.ispartofseries | M.Sc | |
| dc.title | Molecular Characterization of Fungi Producing Aflatoxin in Vigna subterranean (Bambara Groundnut) sold in Three Selected Markets in Enugu Metropolis | |
| dc.type | Thesis |