Microbial Flora and Nutrient Content of Market Bought Smoked African Cat Fish Clarias gariepinus from Jos, Nigeria

Clarias gariepinus, one of the many fishes sold in Nigerian market, is the most preferred smoked fish in Jos where large quantities are smoked and stored for sale. This study assessed the nutritional value and health of smoked C. gariepinus sold in Jos markets.Live and smoked C. gariepinus were purchased from the four major markets in Jos metropolis. Microorganisms isolated from the smoked fish were identified. The live fish were smoked in the laboratory and inoculated with the isolated microorganisms. Nutrient content of the fishes were monitored weekly for four weeks, un-inoculated laboratory smoked fish served as controls.Bacillus brevis, Aspergillus fumigates and Mucor species were isolated from purchased smoked fish. The nutrient value of these fish were significantly lower (p<0.05) than the laboratory smoked fish. There was however a gradual decline in the nutrient content of the infected laboratory smoked fish. The carbohydrate content decreased to zero while the moisture content increased. Mucor had the most significant effect on protein (62.06 ±13.39) and carbohydrate (1.11±0.95) levels in infected fish. pH dropped below7.0 by the end of four weeks in Mucor infected fish and fat content was lowest (14.19±3.82) in A. fumigates infected fish. There was a significant difference (p>0.05) between the nutrient values in the control and infected fish. The microbial content and lower nutrient values of infected fish emphasize the need to ascertain the health and nutrient content of market sold fish. This will ensure that consumers receive optimum nourishment and avoid the likely health implications of consuming infected fish. Keywords: Fish nutrient, smoked Clarias gariepinus, microflora, Jos market

Macro and Trace Element Accumulation in Edible Crabs and Frogs in Alaro Stream Ecosystem, Ibadan

The tissue accumulation of five macroelements (Na, Mg, K, Ca, Fe) and twelve trace elements (Vd, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Pb) were assessed in the organs of the edible frogs; Xenopus laevis and Rana esculentus, and whole body of the crab, Callinestes caught from Alaro Stream Floodplain (Ibadan, Nigeria).The liver of the edible frogs showed higher concentrations of Cu, Mo, and Cd, while Na, Mg, K, V, Mn, Fe, Co, Zn and Pb were higher than the other organs in Rana esculentus. In the liver of Xenopus laevis, Se and Ag were higher than the bone, gut, heart and muscle while Ag was the only trace element with the lowest concentration in the bones of the edible frog in contrast to Ca which ranked highest in the study. Ag was the least accumulated in the whole body of the crab, Callinestes while Ca was the highest mean level of 139364ppm in the study. Significant correlation was recorded between the bioaccumulated macro and trace elements in the crabs and frogs. With the exception of Ag, all the other trace elements exceeded the guidelines and standards given by the Federal Environmental Protection Agency of Nigeria. Public health consciousness and regular monitoring is therefore necessary in the consumption of these aquatic food resources. Macro and trace element accumulation in edible frogs and crabs in a contaminated watershed in the tropical region.Keywords: macro element, trace element, edible frogs, crab