Antibacterial Effects of Uvilla (Physalis peruviana L.) extracts against Listeria spp. Isolated from Meat in Ecuador

Resumen

Listeria spp. are opportunist human pathogens that may cause listeriosis, this illness is associated to ingestion of contaminated foods. Nowadays there are various antibacterial to act against Listeria spp. However, this bacterium has been demonstrated resistance to several antibiotics. In this regards, the antimicrobial activity of eight Physalis peruviana L. extracts obtained from leaves and berries (by aqueous and ethanolic media both lyophilized and fresh state) was evaluated against Listeria spp. previously isolates from meats. The ethanolic extracts showed higher antimicrobial activity than the aqueous extracts, and the MFrE extract inhibited the 95% (57/60), followed by the LFrE extracts with 91.7% (55/60), LLyE with 90 % (54/60) and MLyE with 83.3% (50/60) of the analyzed strains. The activity of these extracts was similar to that shown by the antibiotics Gentamicin and Ampicillin. While the aqueous extracts MFrW and MLyW were the only ones that had acceptable antimicrobial activity. Maceration of fresh leaves and berries showed more antimicrobial activity than lyophilized ones, probably in the lyophilization process, part of the bioactive properties of the uvilla is lost.