Antimicrobial pattern of Ricinus communis crude extracts on bacteria isolated from Musa parasidica

This research was done to determine the antimicrobial activity of castor oil plant parts (seed and leaves) on spoilage microorganisms of plantain fruits and vis-a-vis standard antibiotics. Plantain fruits were subjected to spoilage for 7days.The spoilage bacteria were characterized and identified using conventional and modern methods. The organisms isolated include: Corynabacterium sp., Staphylococus aureus and Proteus vulgaris. Castor oil plant (Ricinus communis) leaf and seed were extracted using ethanol and water. The phytochemical analysis of plant extracts were also carried out. The antimicrobial activities of the ethanol and aqueous extracts were tested on the isolates at different concentrations (100mg/ml, 150mg/ml, 200mg/ml and 250mg/ml). The extracts were effective on the bacterial isolates with range of Minimum inhibitory concentration (MIC) values from 25.0mg/ml -100.0mg/ml, Staphylococcus aureus at 12.5mg/ml – 100mg/ml and Proteus vulgaris at 50mg/ml- 100mg/ml. The aqueous extracts of the leaf inhibited Corynabacterium sp., and Staphylococcus aureus but it did not inhibit Proteus vulgaris. Proteus vulgaris was also not inhibited by the aqueous seed extract, Corynabacterium sp. and Staphylococcus aureus were inhibited only at higher concentrations. Antibiotic susceptibility test showed that Corynabacterium sp., was inhibited more by the ethanolic seed extract than it was inhibited by Amoxicillin at the same concentration of 250mg/ml

Physico-chemical and anti-nutritional characterization of the kernels of some mango (Mangifera indica) cultivars grown in Western parts of Nigeria

Ten mango (Mangifera indica) cultivars grown in western parts of Nigeria were identified as Alphonso, Indesina, Julie, Kent, Mabranka, Magadugu, Peach, Peter, Taymour, and Oori. The percentage weight ratio (PWR) of kernel to fruit, seed to fruit and kernel to seed of the mangoes ranged between 2.38 – 10.79%, 6.36 – 17.21% and 36.22 – 63.35% respectively. The PWR of kernel to fruit (10.79%), seed to fruit (17.21%) and kernel to seed (63.35%) of “Oori” cultivar were significantly higher (p < 0.05) than other cultivars, except the values of PWR of kernel to seed of Indesina (60.05%) and Kent (62.72%). Values of Julie cultivar on the parameters measured were significantly lower (p < 0.05) than others. The range of nutrients of the kernels were protein (6.24 – 8.19%), fat (5.92 – 13.50%), fibre (2.22 – 3.95%), ash (0.52 – 3.54%) and carbohydrate (75.02 – 83.04%). The protein of Julie (7.88%), Indesina (8.05%) and Oori (8.19%) and fat of Mabranka (13.10%) and Alphonso (13.50%) were significantly higher (p< 0.05) than other cultivars. The carbohydrates in the mango kernels was high; although values recorded for Mabranka (75.02%) and Alphonso (75.09%) were significantly lower (p< 0.05) than other cultivars. The pH of fresh mango kernels ranged between 4.10 and 5.80, while titratable acidity was between 9.92 – 64.35mg/100g. The anti-nutrients in the mango kernels were tannin, flavonoid, phenolic compound, oxalate and phytate. Tannin (37.30 – 163.33g/kg), phytate (0.442 – 0.897mol/kg) and oxalate (18.74 – 54.24mg/100g) were significantly different (p< 0.05) among the mango cultivars. Tannin and oxalate contents of Oori (157.33; 54.24g/kg), Alphonso (163.33; 49.55g/kg) and Phytate content of Mabranka (0.442mol/kg), Alphonso (0.453mol/kg) and Indesina (0.478mol/kg) respectively were significantly higher (p< 0.05) compared with other cultivars. Key words: Mango cultivars, percentage weight ratio, nutrients, anti-nutrients

Cellulase Production Potentials of the Microbial Profile of Some Sugarcane Bagasse Dumping Sites in Ilorin, Nigeria

This research work investigated cellulase production potentials of the microbial profile of three sugarcane bagasse dumping sites at Zango area, Ilorin, Nigeria. The microbial isolates were screened for cellulase production with a view to select the best organism for eventual cellulase production. Pour Plate method was used for the isolation and a total of thirteen (13) different organisms including both fungal and bacterial species were isolated and screened. Six (6) fungal isolates identified as Mucor racemosus, Aspergillus niger, Aspergillus flavus, Neurospora sitophilus, Penicillium oxalicum and Penicillium citrinum were isolated, while seven (7) different bacterial species isolated include Clostridium cellobioparum, Clostridium thermocellum,Bacillus subtilis, Bacillus pumillus, Lactobacillus spp, Pseudomonas flavescens and Serratia spp. Generally, bacterial isolates were more in abundance than fungal species. However; fungal isolates were constant and were isolated through the experimental period of three weeks. All the isolates showed cellulase production potential in varying degrees as reflected in the clearance zone around their colonies. Fungal isolates produced more cellulase than the bacterial isolates. Mucor racemosus had the highest clearance zone (75.0 mm) among the fungal isolates while Clostridium cellobioparum (35.0 mm) were the best producer among bacterial isolates. The least producer among fungal isolates, Penicillium citrinum (40.0 mm), is a little more than the bacterial cellulase producer (35.0 mm) and is far greater than the least bacterium Serratia spp (14.0 mm)