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This study evaluated the effects of dietary sesame oil extracted from autoclaved, roasted and fermented sesame seed meal on growth, nutrient utilization and muscle fatty acid composition of Til-aqua natural male tilapia. Four isonitrogenous (crude protein content: 35%) and iso-energetic (Gross energy: 19.36 KJ/g) diets were formulated to contain 3% of either fish oil (FO) or oils extracted from autoclaved (AO), roasted (RO) or fermented (FEO) sesame seed meals. Each diet was assigned to duplicate groups of Til-aqua natural male tilapia (initial average weight, 2.78±0.02 g) using recirculating aquaculture systems for 56 days. Specific growth rate 0.8 (2.93%/day) and metabolic growth rate (9.68 g/kg /day) recorded in the group fed RO diet were significantly lower (P

Preliminary studies on the antimicrobial properties of various methods of extraction of Carica papaya (Pawpaw) seeds, Citrus paradisa (Grapefruit peel) and Piper guineese (Black pepper) seeds against eleven bacteria ( Proteus mirabilis, Escherichia coli, Staphylococcus aureus, Acinetobacter sp, Klebsiella pneumoniae, K. oxytoca, Pseudomonas lundensis, Bacillus subtilis, B. megaterium, Citrobacter freundii and Enterobacter cloacae) associated with fresh catfish spoilage were investigated using the cup-plate diffusion method. Cold water, hot water and ethanol were the different extraction solvents used while the concentrations were 0.1g/ml, 0.2g/ml, 0.3g/ml, 0.4g/ml and 0.5g/ml. Generally, hot water extraction of the plant materials was most effective (p < 0.01) with the highest mean zone of inhibition of 4.42 ~c 0.38mm followed by ethanol extraction (3.55 ~c 0.47mm). The most susceptible bacteria was Enterobacter cloacae with the highest mean zone of inhibition of 22.6 ~c 3.50mm. This investigation indicates that the antimicrobial compounds in grape peel and black pepper are best liberated when extracted with ethanol while that of pawpaw is best extracted with hot water.

On average, Nigeria loses 30-50% of its fish harvest to spoilage. This exacerbates her fish demand-supply gap; hence the need to devise means of mitigating the spoilage. This paper reports the findings of a study that delved into the antimicrobial properties of Grape Fruit ( Citrus paradisa ), Pawpaw ( Carica papaya ) and Black Pepper ( Piper guineese ) extracts on organisms associated with fish spoilage. In the study, the antimicrobial effect of five concentrations (0.1, 0.2., 0.3, 0.4 and 0.5g/ml) of ethanolic, cold and hot water extracts of these plants on spoilage organisms associated with catfish ( Clarias gariepinus ) were assessed, through measuring inhibition zones, using the cup plate diffusion method. The inhibition zones were found to significantly differ, across extraction method; plant material and extract concentration. Hot water was found to be the best extraction method, with a mean inhibition zone of 4.42 +- 0.38mm; followed by ethanolic and cold water methods, with 3.55 +- 0.47 mm and 0.60 +- 0.15 mm respectively. Among the plant materials, grape peel had the best antimicrobial activity, with a mean inhibition zone of 3.70 + 0.40mm against the eleven microorganisms tested, followed by black pepper (2.68 + 0.42mm) and then pawpaw seed (2.1 + 0.32mm). Key words: Antimicrobialactivity; Piper guineese; Citrus paradisa; Carica papaya