ABSTRACT

Vegetables are important protective food and highly beneficial for the maintenance of health and prevention of diseases. This study was aimed at identifying and classifying the microorganisms (bacteria and fungal) associated with rotten onions bulb. With the following objectives which are to isolate the Microorganisms found in rotten onions bulb, identify the Microorganisms in rotten onions bullb. Ten (10) samples of rot onion bulbs used for this study were obtained from onion sellers at popular markets which are Amawon market, Ahiaeke market, and Ndoro market in Ikwuano L.G.A, Umuahia, Abia State. The onions were purchased in batches and brought to the laboratory for Microbiological analysis.  The sample was processed by standard bacteriological method. From the result it shows that bacteria load of rotten onions sample 1.0 x104   to 6.0 x101 while the fungal ranges from 1.5 x103   to 1.5 x101 . The result also shows the bacteria and fungi isolated from rotten onions bulb samples which were identified by morphological characteristics on media, microscopy, biochemical and sugar fermentation methods. These reveals the major bacterial isolates to belong to Bacillus species, Escherichia coli, Proteus spp and Non-haemoltyic streptococcus and fungi isolates are Rhizopus spp, Candida spp and Mucor spp. The result also shows the occurrences of bacteria, Non-hemolytic streptococcus   (41.17%) followed by E. coli (23.52%) has the highest percentage occurrences, while the bacteria isolates with the lowest percentage occurrence are Proteus spp. (17.64%) and Bacillus spp.  (17.64%), fungi isolates Candida spp. (55.55%) has the highest percentage occurrence followed by Mucor spp. (33.33%), while the fungi isolates with the lowest percentage occurrence is found in Rhizopus spp. (11.11%). Rotten onion bulbs harbor a wide range of bacteria and fungi species. The pathogenic microorganisms implicated in the rotten onion bulbs samples are of public health importance.  It was also noted that some of the bacteria and fungi isolates have history of pathogenicity which some fungi involved are to deposit mycotoxins which are inimical to health.