Among the potential benefits of probiotic lactic acid bacteria (LAB) is their practical use for biopreservation of foods, fungal decontamination, and novel biotherapy. A number of ready to eat foods hawked in streets of Nigeria such as garri are prone to contamination by mycotoxin-producing fungi. In this study the inhibitory effect of lactic acid bacteria (LAB) (sourced from local foods (nono and kunun- zaki)) and their bacteriocins-derivatives on aflatoxin B1 -producing Aspergelius flavus was conducted. Out of the five LAB isolates screened three (two strains of Lactococcus and one of Pediococcus sp had high indices of probiotic potentials and bacteriocins extracts were obtained from them and used for the inhibition study. Fourty samples of garri sold in Jos metropolis were screened for A. flavus and their abilities to produce Aflatoxin B1 using the Coconut Extract Agar (CEA) and Ammonia Vapour Test (AVP) methods. The three most probiotic LAB and their respective crude baterioncin extracts were used to test for their inhibitory effect on aflatoxin producing A. flavus isolates. The results of the study showed that while only 17 samples (42.50%) had A. flavus in them, only three of the fungi ((17.65%) demonstrated capacity to produce Aflatoxin B1, making (7.5% of the total number of garri samples that had aflatoxin-producing A. flavus. The inhibition of fungal growth by LAB and bacteriocins was dose dependent. At an inoculum concentration of 1 ml, Pediococcus sp had the highest mean zone of inhibition of 43.0 mm followed by Lactococcus sp (Strain LAC20G with radial diameter 38.0mm and Lactococcus sp (LAC20G) which had a radial diameter of 29.3mm respectively. The results of the study portend that the growth of aflatoxin producing Aspergillus flavus in ready to eat foods such as garri could be prevented by application of appropriate dosages of bacteriocins extracts from lactic acid bacteria.

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The conventional methods of identification of Salmonella involving microbiological enrichment and successive identification mostly are tedious, time consuming and not specific. Therefore, the aim of this study was to utilize molecular techniques to characterize Salmonella species isolates from some Hospitals in Jos, Nigeria. The 10 isolates collected from some Hospitals in Jos, Nigeria were screened for Salmonella using conventional biochemical methods. The positive isolates were identified using polymerase chain reaction (PCR) for discernment of invasion A (invA) gene at explicit molecular size (284 bp) utilizing explicit primers (forward and reverse). Sequencing of the invA gene was performed and the similarities and differences between our invA gene and published sequences on GenBank were assessed. Seven out of ten confirmed Salmonella species isolates were positive to the invA gene while the remaining three were negative. The homology level of nucleotide sequence (97.746%) demonstrated high similitude between the local isolates and the other sequences on GenBank. Molecular characterization of the Salmonella isolates provides data about the virulence of the pathogen just as its relatedness to different organisms which offer data about the genome of the organisms and are helpful for epidemiological examinations. Therefore, Molecular methods which enable the detection of virulent genes are extremely important surveillance tools that are required to assist in curbing the escalation of infections caused by Salmonella.

Abilities of Achyla orion and Allomyces anomalus isolated from some crude oil polluted aquatic environments in Nigeria to biodegrade petroleum and petroleum products were determined. Baiting method using hemp and sesame seeds was used to isolate the two species of aquatic phycomycetes. The species were grown in liquid broth culture made of minimal mineral salts supplemented separately with petrol, diesel and kerosene and incubated at room temperature with agitation for two weeks. Biodegradation was monitored using spectrophotometer at 600 nm wavelength. Fat/lipid was extracted from pellets resulting from centrifugation of the final broth culture using selected fat extractor and quantified. A. anomalus gave highest mean growth values in broth medium supplemented with diesel (0.970) and kerosene (1.302) while that supplemented with petrol recorded the least mean growth value of 0.663. The mean growth values for A. orion showed a similar trend. Crude fat/lipid production was highest for both isolates grown in diesel supplemented broth culture medium and least for both isolates grown in petrol supplemented broth culture medium. These results imply that these two species of aquatic phycomycetes were able to degrade diesel and kerosene better than petrol with corresponding production/accumulation of fat/lipid as biodegradation product.

Aim: Consequent from increased demands for lipase enzymes for various purposes, the soil environment of Jos North LGA of Plateau State, Nigeria was surveyed for lipase-producing fungi. Materials and Methods: Soil samples (300 g each) were collected randomly in triplicates from five locations (Terminus, Agwan Rukuba, Gada Biu, Farin Gada and Katako) in Jos North metropolis. Physicochemical properties (soil type, pH, temperature) and fungal counts of the soils were determined. Fungal isolates from the soil samples were preliminarily screened on phenol red agar for lipase production. Lipase activities of isolates with higher lipolytic potentials were determined using the spectrophotometric method with p-nitrophenyl dodecanoate serving as lipid substrate. Results: The soil samples were mostly of sandy and loamy types. Mean pH and temperature ranges of the soils were 6.7-7.5 and 23.5ºC - 26.8ºC respectively. Total fungal counts of the soil samples ranged between 2.0 x 103 cfu/g and 3.9 x 104 cfu/g with Angwan Rukuba having the highest count. Fungal isolates from the study included Aspergillus niger (100%), Aspergillus ochraceus (60%), Fusarium sp. (20%), Penicillium sp. (40%), Rhizopus stolonifer (60%) and Rhizopus sp (60%). R. stolonifer produced the highest lipolysis zone diameter (3.69 mm) on phenol red agar. A lipase activity of 0.183µmol/min/ml was recorded for R. stolonifer while A. niger, Fusarium sp. and Rhizopus sp. had equal lipase activities of 0.184µmol/min/ml. Conclusion: The findings show that the soil environment of Jos North LGA contain lipase-producing fungi which could be harnessed for industrial and environmental purposes after optimising the lipase production process.