Antagonistic properties of microogranisms associated with cassava (Manihot esculenta, Crantz) products

The antagonistic properties of indigenous microflora from cassava starch, flour and grated cassava were investigated using the conventional streak, novel ring and well diffusion methods. Antagonism was measured by zone of inhibition between the fungal plug and bacterial streak/ring. Bacillus species were more effective to inhibit the growth of Aspergillus niger, A. fumigatus, Fusarium moniliforme and Rhizoctonia sp. Pseudomonas fluorescens, Escherichia coli and Saccharomyces sp. inhibited the growth of A. niger, A. flavus and F. moniliforme. There were considerable variations in inhibitory activity. The zone of inhibition was more apparent in the novel ring method. Percentage inhibition increased to 78% in the Ring method and 62% in streak method after 168 h of incubation. Lactobacillus brevis, L. acidophilus and Bacillus subtilis inhibited the growth of E. coli and Staphylococcus aureus. Inhibition of the pathogenic microorganisms was probably due to the production of organic acids and bacteriocins.African Journal of Biotechnology Vol. 4 (7), pp. 627-632, 200

Enumeration, Identification And Occurrence Of Staphylococci In Cooked Foods And Hand Rinsed-Water From Eleven Local Government Areas Of Ibadan

This project aimed at isolating, identifying and determining the level of occurrence of staphylococci in cooked foods,. “Amala”, “fufu”, “rice”, “beans”, “ewedu”, stew and hand-rinse water were collected from restaurants in the eleven Local Government Areas (LGA) of Ibadan. Staphylococci were isolated, enumerated and characterized using standard pour plating, culturing and biochemical test methods. Nine different species of Staphylococcus were identified as S. aureus, S. hyicus, S. epidermidis, S. intermidius, S. saprophyticus, S. arrieta, S. carnosi, S. haemolyticus and S. schleifer. In all the samples, Staphylococcusaureus occurred in 32 times, while S. Schleifer,S. hyicus, S. epidermidis, S. intermidius, S. saprophyticus, S. arrieta, S. carnosi and S. haemolyticus occurred in 1, 11, 14, 9, 4, 4, 2 and 8 times respectively. Among the food samples, staphylococcal load was highest (9.8 x 102 cfu/ml) in “fufu” from Akinyele LGA. In contrast, “ewedu” from Akinyele LGA showed the lowest population (1.2 x 102 cfu/ml) of staphylococci. KEYWORDS: Ibadan Local Government Areas, Staphylococci, Population, Occurrence and Identification

Genetic variation and relationship in Staphylococcus aureus isolates from human and food samples using random amplified polymorphic DNAs

A genetic characterization of 18 different isolates of Staphylococcus aureus using random amplified polymorphic DNAs (RAPDs) was carried out. Out of one hundred primers tested, ten showed polymorphism. The amplification reactions with the 10 primers generated 88 bands, 51 of which is polymorphic with band size ranging between 200 and 3,000 bp. Variation and relatedness between different isolates were determined by converting RAPD data into a Jaccard similarity matrix and analysed by UPGMA (unweighted pair-group method, arithmetic average) to produce completely twelve different groups at 100% Jaccard similarity and at 50% coefficient of similarity. The isolates were classified into two major groups, the first comprises of mildly and weakly virulence, while the other group are the highly virulence Staphylococci. The results demonstrated that the RAPD technique may be of great use in the classification of Staphylococcus aureus.African Journal of Biotechnology Vol. 4 (7), pp. 611-614, 200

Effects of Electromagnetic fields on the Physicochemical Properties of Waste Water Samples from Selected Industries in Akure Metropolis

Wastewater is one of the most critical problems of both middle and low income countries is improper management of vast amount of wastes. The research is to determine the physicochemical characteristics of the wastewaters and also to asses the effect of the Electromagnetic field (EMF) on the physicochemical factors of the waste waters Waste water samples were collected from two industries in Akure Metropolis. The waste water samples were subjected to physicochemical analyses before and after exposure to Electromagnetic field (EMF) at 1150nT, 1310nT, 3000nT, 5000nT. The presence of some bacteria in the waste water collected from different companies showed their occurrence at different hours during the treatment of the wastewater sample with different EMF strength. a. From the two industries, before EMF treatment industry A had the highest pH value (7.74), Temperature (27.00oC), Total Solid (277.00mg/l.), Total Disolved Solids (256.00mg/l.) Industry B had Total hardness (994mg/l), Chemical Oxygen Demand (13.20mg/l), Potassium (13.23g/l), Biochemical Oxygen Demand (9.60mg/l) Zinc (1.24ppm) and Copper (0.07ppm). From the two industries, after EMF treatment pH (6.47), Turbidity (0.29NTU), Biochemical Oxygen Demand (4.60), Chemical Oxygen Demand (5.40). Industry B had Chloride (10.47mg/l), (600 mg/l). Sulphate (8.70mg/l), after exposure to EMF, the values above listed shows physicochemical factors reduced significantly. Therefore from the study, it was observed that EMF treatment has a significant effect on the bacteria load and physicochemical condition of the waste water samples

Effects of Electromagnetic Fields on the Microbial Load of Waste Water Samples from Selected Industries in Akure Metropolis

Wastewater is any water that has been adversely affected in quality by anthropogenic influence which can serve as habitat for pathogenic microbes and can constitute to health hazard of the populace. The present study was designed to enumerate and identify microorganisms in wastewaters and to investigate the effect of Electromagnetic Field (EMF) on the populations and identities of bacteria in the wastewaters from selected industries in Akure Metropolis. Wastewater samples were collected from two different industries in Akure Metropolis. The waste water samples were subjected to microbiological analyses before and after exposure to Electromagnetic field (EMF) at 1150nT, 1310nT, 3000nT, 5000nT. The presence of some bacteria in the waste water collected from different companies showed their occurrence at different hours during the treatment of the wastewater sample with different EMF strength. It was observed that at the early part (hours) of the experiment the heavy presence of microbes were seen but as the experiment progresses the microbial population were observed been reduced. It is therefore recommended that wastewater from industries should be treated with EMF before discharging them to the other water bodies so as to avoid contamination. This will help reduce microbial population that constitute a serious hazard to public health. And could also help protect other life forms inhabiting the water body and thus guard against ecological imbalance of the microbiota

Fermentation Studies on Roselle (Hibiscus Sabdariffa) Calyces Neutralised with Trona

The effect of trona on the fermentation of roselle calyces was evaluated. The addition of trona to the calyces raised the initial pH from 3.3 to 5.3. The important microorganisms of roselle calyces fermentation were enumerated, isolated and identified. The fungi isolated consist of one yeast identified as Saccharomyces cerevisiae and two moulds, Apergillus niger and Aspergillus flavus. Of the aerobic bacteria, only Escherichia coli, Bacillus subtilis and Klebsiella sp. were isolated. The total titratable acid (TTA) value increased throughout the fermentation (0.027-0.043). The nutritional evaluation showed that there was an increase in the protein (6.56%), lipid (4.25%) and carbohydrate contents (74.33%) of the fermented sample with a higher ash content (4.54%) in the unfermented sample. The mineral contents (PPM); Zn (31.86), Fe (12.35), Mg (132.00), Ca (294.31), Na (214.62) and K (382.13) of the fermented sample were generally low. This study reveals that trona can be used to neutralize the acid in roselle calyx and that fermentation can greatly influence the nutritional composition positively. Keywords: Roselle, calyces, Trona, nutritional evaluation, fermentation J Food Tech in Africa (2002) 7, 75-7