Antibacterial Effects of Pyrolysis Oil Against Salmonella Typhimurium and Escherichia coli

Many issues have been found to be related to food preservation and food contamination caused by various pathogenic bacteria in recent years. Many antibacterial agents act efficiently against Gram-positive foodborne bacteria; however, they are less effective against Gram-negative foodborne bacteria. In the present study, an attempt has been made to evaluate the antibacterial activity of pyrolysis oil manufactured from Pinus densiflora (PLO) against two Gram-negative foodborne pathogenic bacteria, Salmonella Typhimurium and Escherichia coli O157:H7. PLO possessed potent antibacterial activity against both foodborne pathogenic bacteria, as indicated by inhibition zones of 10.33-12.33 mm and minimum inhibitory concentration and minimum bactericidal concentration values of 250-500 μg/mL and 500-1000 μg/mL, respectively. PLO at the minimum inhibitory concentration exhibited an inhibitory effect on the viability of the bacterial pathogens with leakage of 260 nm absorbing materials, an increase in the relative electrical conductivity, and loss of salt tolerance capacity. PLO exhibited promising antibacterial activity against both of the Gram-negative foodborne pathogenic bacteria and thus it can be utilized in the food sector and pharmaceutical industries for the development of antibiotics and preservatives.