Microorganisms Associated With Spoilage Of Stored Vegetables In Uyo Metropolis , Akwa Ibom State , Nigeria

Microorganisms associated with spoilage of stored vegetables were studied using standard microbiological methods. The analysis was done on carrots, cucumber, cabbage and onions with soft rot symptoms using various media. It showed that Escherichia coli (28.6%) were the most predominant bacterial isolates associated with vegetable spoilage in Uyo metropolis. This was followed by Enterobacter spp. (21.4%), Staphylococcus aureus (14.3%), Erwinia spp. (14.3%) and Pseudomonas spp. (14.3%) while Salmonella spp. (7.1%) was least predominant. The results obtained from the microorganism s associated with the spoilage of stored vegetables showed that the total aerobic counts for cucumber ranged from 1.28 x 10 to 3.20 x 10 cfu/g and the total coliform count ranged from 2.35 x 10 to 3.28 x 10 cfu/g. The total aerobic count for carrots ranged from 2.07 x 10 to 2.20 x 10 cfu/g while the total coliform count ranged from 2.80 x 10 to 3.00 x 10 cfu/g. The total aerobic count for cabbage ranged from 1.43 x 10 to 2.10 x 10 cfu/g while the total coliform count ranged from 3.10 x 10 to 4.20 x 10cfu/g. Generally, the total Salmonella-Shigella counts ranged from 0.0 x 10 to 1.80 x 10 cfu/g. Only cabbage had the highest count for total Salmonella-Shigella. The aerobic count for onions ranged from 1.8 x 10 to 2.0 x 10 cfu/g and the total coliform count ranged from 2.00 x 10 to 3.10 x 10 cfu/g. Fungi isolated from these vegetables were Aspergillus niger, Rhizopus stolonifer and Aspergillus fumigatus with fungal count ranging from 1.80 x 10 to 3.0 x 10 cfu/g. The frequency of occurrences showed that bacterial isolates were most predominant (63.6%) compared to the fungi isolates (36.4%). No protozoa or viruses were found to be associated with vegetable spoilage in Uyo metropolis. The frequency of occurrences of bacteria isolates showed that Escherichia coli (28.6%) were most. This was followed by Enterobacter spp. (21.4%), Staphylococcus aureus (14.3%), Erwinia spp. (14.3%) and Pseudomonas spp. (14.3%). Salmonella spp. (7.1%) was least predominant. It also showed that of the three fungi species isolated from vegetables, Rhizopus stolonifer (37.5%) and Aspergillus fumigatus (37.5%) were most predominant while Aspergillus niger (25.0%) was least predominant. Pathogencity tests revealed that all the isolates were pathogenic to the different vegetables examined leading to rapid disintegration of treated fruits in 3-5 days. It showed that each infected vegetable gave the initial organism that caused the spoilage of the fruit. The rot symptoms obtained were similar to those observed previously on the fruits when subjected to identification procedures. The presence of indicator and other organisms examined in this study is of special concern and perhaps the greatest danger associated with food for human consumption is contamination by human excrement. The need for microbial assessment of vegetables for production of salads and other use is also emphasized to reduce possible contamination. [Adebayo-Tayo BC, Odu NN, Esen CU, Okonko IO. Microorganisms Associated With Spoilage Of Stored Vegetables In Uyo Metropolis, Akwa Ibom State, Nigeria. Nature and Science 2012;10(3):23-32]. (ISSN: 15450740). http://www.sciencepub. net. 4