The economic and ecological function of pectinase enzymes in industries is gaining much attention with the need of highly productive strains of microorganisms to reduce production cost. The present investigation is a comparative evaluation of Bacillus sp. pectinases. The three isolates isolated from agro-waste, Bacillus stearothermophilus, Bacillus cereus and Bacillus subtilis, showed very high pectinase activities with pectin as the substrate. The three isolates also showed varying degree of preference for banana peels and wheat bran but their activity towards orange peel was very low compared to other substrate. The effect of temperature on the pectinase of the three isolates showed that B. stearothermophilus had optimum temperature at 60°C while B. cereus and B. subtilis both showed optimum activity at 50°C. On the effect of pH, B. stearothermophilus, B. cereus and B. subtilis showed optimum pectinase activities at pH 7.5, 8.0 and 9.0, respectively. Metal ions enhanced the activity of pectinase produced by the three isolates. The study exhibited that B. stearothermophilus gave the most pectinase activity, optimum temperature and a moderate alkaline pH, possibly making it a better source for industrial purpose.

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Mushrooms are fungi that are unique in the recycling of plant biomass through decomposition in the process of which they also serve as food for man. These functions are carried out through the extracellular digestion of plant biomass with a consortium of enzymes. This study examined the effect of carbon-nitrogen ratios (C/N) of three lignocellulosic substrates, namely, corncob (C/N 120:1), sawdust (C/N 325:1) and waste paper (C/N 400:1) on the yield of Pleurotus pulmonarius. The experimental design was factorial laid out in Randomized Complete Block Design (RCBD). Tissue culture was made on Potato Dextrose Agar (PDA) which was transferred to boiled sorghum grains for spawn making. The substrates were pasteurized and then inoculated with P. pulmonarius. Substrates were pasteurized (immersed in hot water for 3 hours) and inoculated with P. pulmonarius. Proximate analysis of the fruiting bodies was done to determine crude protein, crude fat, moisture content, dry matter, ash, crude fiber and carbohydrate. Carbon-nitrogen (C/N) ratio of the substrates was also determined. Corncob has C/N ratio of 120:1. The yield performance of corncob was the highest for weight (86 ± 0.01 g), length of stipe (3.55 ± 0.04 cm) and diameter of pileus (7.3 ± 0.07 cm). Means separation by least significant difference (LSD) showed that the yield parameters for corncob were statistically different from other substrates used.The proximate analysis of dried P. pulmonarius showed that corncob had a protein content of 17.37% ± 0.80% and moisture content of 0.69% ± 0.01% respectively, while sawdust and corncob had crude fibre contents of 1.79 ± 0.02 and 1.79 ± 0.01 respectively. Conclusively, having an idea of the carbon-nitrogen ratio of the substrate to be used for mushroom cultivation, manipulating the nutritional composition of mushrooms can be enhanced by enriching the growth substrates/media.

The antibiotic susceptibility profile and the association of β-lactamase production to antibiotic resistance in Staphylococcus aureus strains were analysed. The disk diffusion antibiotic susceptibility pattern was conducted on S. aureus strains cultured from clinical specimens using standard bacteriological methods. The β-lactamase production was assayed using the modified Perret's iodometric assay and data were statistically analysed. Of the 107 S. aureus isolates identified, 77 (72%) of the isolates were multi-drug resistant and 75 (70.1%) produced β-lactamase. β-lactamase production and resistance to amoxicillin, amoxicillin/clavulanic acid (augmentin) and ceftriaxone resistance was significant (p-value< 0.05). The study suggests strict infection control measures and encouragement of prudent antibiotic use.

Aim:The study assessed and compared the antibacterial activities of different honey types in Southwest Nigeria. It also compared antibacterial potency of the honey with a standard antibiotic. This was with a view to ascertain and providing information on cheaper alternative potent antibacterial product of natural source as well to confirm the antibacterial efficacy of the honey in Southwest, Nigeria. Materials and Methods: The sensitivity testing of honey samples was determined using agar-well diffusion method. The minimum inhibitory concentration of honey samples was determined using broth tube dilution method. Minimum bactericidal concentration of honey samples was determined. The data obtained were analyzed with appropriate statistical methods. Results: The zone of inhibitions exhibited by all honey samples against the test bacteria ranged between 6 ± 0.0 and 30.7 ± 1.2 mm. The death rate ranges between 52.1% and 94.6% in the dark amber honey sample (H9) after 120 min of contact time at the same concentration. Conclusion: In this study, super dark amber honey shows the highest antimicrobial property which compared favorably with the standard antibiotic (streptomycin). This honey has shown to have a potent broad spectrum antibacterial activity. However, further studies are recommended to assess its practicality in terms of use in the clinical setting.