Phytochemical Screening and Antibiogram of Ethanolic extracts of Costus afer stem on Microorganisms isolated from Fresh siluriformes

The Phytochemical and antibiogram of Costus afer stem on microorganisms isolated from the skin and other body part of fresh Siluriformes was studied using standard (analytical procedures). Different sample points of the fresh Silurformes were accessed microbiologically (Abdomen, Back Tail and Fins). The abdomen had the bacterial count which ranged from 5.4 x 104cfu/g to 7.2 x 104cfu/g and fungal count which ranged from 0.5 x 104cfu/g to 1.1 x 104cfu/g. The fins had the bacterial counts of 1.2 x 104 cfu/g to 5.5 x 104cfu/g and the fungi ranged from 0.2 x 103cfu/g to 1.2 x 104cfu/g. The bacterial isolates identified and their percentage frequencies of occurrence were Pseudomonas sp (36.34%) as the highest, Micrococcus sp (23.41%), Streptococus sp (20.49%), Staphylococcus sp (18.05%) and Proteus sp(11.71%) and the least was Proteus sp (11.71%). The fungal genera identified and their percentage frequencies of occurrence were Aspergillus sp (42.86%), Penicillium sp (20.41%), Mucor sp (25.51%) and Rhodotorula sp (11.22%). The phytochemical and qualitative analyses of Costus afer with ethanol reveal the presence of Alkaloids (0.614), Flavonoids (0.401), Saponins (3.003), Tannins (0.971) and Cyanogenic glycosides (0.764). Organisms like Staphylococcus sp and Micrococcus sp were susceptible to the aqueous extracts at 200% concentrations while the grams negative organisms were highly resistant to the ethanolic extract at all concentration. From the result, Costus afer can be used to sterilize fresh Siluriformes during preparation as it is capable of reducing the level of some microorganisms and enhancing the safety of the fish delicacy for consumption.