Promising antimicrobial and antioxidant extracts of Murta leaves (Ugni molinae Turcz): Shelf-life extension and food safety

• Chilean native Murta leaf extracts are a rich source of antioxidants and have antimicrobial activity.
• The extracts are highly efficient against the harmful food-pathogen Listeria.
• Murta leaf extracts can be used to extend the shelf-life of foods and to ensure the food safety.

Murta leaves are known for their beneficial effects since long time. Therefore, the aim of present study was to determine the antimicrobial and antioxidant activity of different extracts from Murta (Ugni molinae Turcz) leaves. Three extracts were obtained from Murta leaves using water or ethanol (50%, v/v) as solvents with different solid-to-solvent-ratios. The extracts were characterized in terms of their antimicrobial activity, antioxidant capacity and total polyphenol content. An extract from 1.5 g of Murta leaves obtained with 20 mL of 50% ethanol showed the highest polyphenol content with 309.4 mg gallic acid/g and the highest growth reduction of Listeria innocua (ATCC 33090), inhibiting 4.9 and 4.8 log cycles after 2 and 24 h of contact, respectively. The ethanolic extract of Murta leaves provides a natural potential antioxidant and antibacterial additive for food production.