Bacterial communities associated with retail alfalfa sprouts

Fresh produce, including salad, is increasingly implicated in foodborne outbreaks. Although studies have been carried out to detect specific human pathogens from fresh produce, the total bacterial community associated with fresh produce is poorly understood. In this study, we characterized the bacterial community associated with alfalfa sprouts, using a culture-independent method. Four retail-purchased alfalfa sprout samples were obtained from different producers, and the bacterial community associated with each sample was determined by 16S rDNA profiling. Our results indicate that alfalfa sprouts sampled in our study shared significant similarities in their bacterial communities. Proteobacteria was the dominant phylum detected from all alfalfa sprout samples, with Enterobacteriaceae, Oxalobacteraceae, Moraxellaceae, and Sphingomonadaceae as the most frequently detected families. These results indicate that growth conditions of alfalfa sprouts should be taken into consideration to prevent the proliferation of pathogenic proteobacteria such as Escherichia coli O157 and Salmonella.