ABSTRACT
The demand for green leafy vegetable as a crucial component of daily diet is on the rise because of its high phytochemical constituents. They are usually consumed raw or with little or no heat treatment. Therefore, this study aimed at assessing the bacteriological quality of green vegetables subjected to different preparative treatment. Oha (Pterocarpus mildraedii), Shoko (Celosia Argentia), Ugu (Telfairia Occidentalis), Ewedu (Corchorus olitorius) and Green (Amaranthus Hybridus) were randomly purchased from an open market in Benin City, Edo State. Ten (10) gram of each green leafy vegetable was chopped aseptically, then treated by soaking in 90 ml of distilled water, salt solution and hot water. Using untreated green leafy vegetables as control, the bacterial count of each sample was determined using pour plate method, diverse bacterial genera were cultured using Bacillus cereus, mannitol salt, MacConkey and nutrient agars. Furthermore, the bacterial isolates obtained were identified with selected morphological and biochemical tests. Antimicrobial susceptibility testing of all bacterial isolates was assessed using Kirby Bauerβs method. All the treated green leafy vegetables had varying levels of bacterial growth ranging from 1.0 x 103 - 3.0 x 103 cfu/g and was lower than the control. By treatment method, the mean total bacterial counts for water washed samples had highest bacterial counts and that of blanching had the least count. The overall best treatment that effectively reduces the amount of bacterial on the samples was the blanching method. The bacterial counts obtained from the vegetables sampled irrespective of treatment method were within the permissible limits except for enterobacteriaceae which exceeded the limit. The following 9 drugs, namely, ampicillin (30 πg), ampiclox(30 πg), ciprofloxacin (10 πg), erythromycin (20 πg), gentamycin (10 πg), pefloxacin (10 πg), rocephin (30 πg), septrin (30 πg), septrin (30 πg), zinnacef (20 πg), were used to determine the antibiogram of the isolates with Bacillus spp showing susceptibility for all commonly used antibiotics. The findings revealed that vegetables are potential vehicles for transmitting food borne illnesses thus the need to develop practical strategies geared toward proper food safety.
