MOLECULAR CHARACTERIZATION OF Escherichia coli PATHOTYPES ASSOCIATED WITH THE SOIL OF LETTUCE PLANTS FROM OJO-IBA AREA, LAGOS STATE.

Abstract

Among leafy green vegetables, lettuce is consumed fresh and, in most cases, not washed by consumers before consumption. It is presumed that the soil borne pathogenic E. coli associated with vegetable forms are usually from organic manure such as cow dung, poultry manure and other faecal contaminants are known to be of public health concern to both vegetable farmers as well as consumers of such vegetables. The major objective of this study was to determine the molecular characterization of Escherichia coli pathotypes associated with the soil of lettuce plant. The soil of lettuce fields, on the other hand, has not been tested for the presence of pathogenic E. coli. As a result, this research is based on soil from lettuce fields that has been routinely treated with poultry manure. A molecular method was used, specifically the utilization of multiplex PCR. All twelve isolates were identified as potential Enterobacteriaceae containing E. coli, on Sorbitol MacConkey Agar, MacConkey Agar and also biochemically identified. Further identification with multiplex PCR revealed that out of the twelve samples, one was positive with E. coli. Using multiplex PCR, the E. coli was found to be pathogenic. In conclusion, the agricultural soil samples collected from Ojo-Iba area, Lagos state harbour pathogenic E. coli, which could be transferred to fresh Produce (Lettuce) intended for human consumers. Some of the isolates harboured either the Human est A and Porcine est A genes making them enterotoxigenic Escherichia coli (ETEC) and highly virulent, thus capable of causing severe forms of infection in human beings.