Plant extracts are a rich source of natural compounds with antimicrobial properties, which are able to prevent, at some extent, the growth of food-borne pathogens. The aim of this study was to investigate the potential of polyphenolic extract from cladodes of Opuntia ficus-indica (L.) Mill. to inhibit the growth of some enterobacteria and the biofilm formation by Staphylococcus aureus. Opuntia ficus-indica cladodes at two stages of development were analysed for total phenolic content and antioxidant activity by ORAC and TEAC (in vitro assays) and by CAA-RBC (ex vivo assay). The LC/MS-TOF analysis of the polyphenolic extract revealed high levels of p-hydroxybenzoic acid derivatives, isorhamnetin derivatives and rutin, particularly in the immature cladode extract. Opuntia cladodes extracts showed a remarkable antioxidant activity (in vitro and ex vivo), a selective inhibition of the growth of Gram-positive bacteria, and an inhibition of Staphylococcus aureus biofilm formation. Our results suggest that Opuntia ficus-indica cladode extracts could be employed as functional food, due to the high polyphenolic content and antioxidant capacity, and used as natural additive for food process control and food safety.
Antimicrobial and antibiofilm activity against Staphylococcus aureus of Opuntia ficus indica (L.) Mill. cladode polyphenolic extracts
Blando Federica;Russo Rossella;Frassinetti Stefania
2019
Abstract
Plant extracts are a rich source of natural compounds with antimicrobial properties, which are able to prevent, at some extent, the growth of food-borne pathogens. The aim of this study was to investigate the potential of polyphenolic extract from cladodes of Opuntia ficus-indica (L.) Mill. to inhibit the growth of some enterobacteria and the biofilm formation by Staphylococcus aureus. Opuntia ficus-indica cladodes at two stages of development were analysed for total phenolic content and antioxidant activity by ORAC and TEAC (in vitro assays) and by CAA-RBC (ex vivo assay). The LC/MS-TOF analysis of the polyphenolic extract revealed high levels of p-hydroxybenzoic acid derivatives, isorhamnetin derivatives and rutin, particularly in the immature cladode extract. Opuntia cladodes extracts showed a remarkable antioxidant activity (in vitro and ex vivo), a selective inhibition of the growth of Gram-positive bacteria, and an inhibition of Staphylococcus aureus biofilm formation. Our results suggest that Opuntia ficus-indica cladode extracts could be employed as functional food, due to the high polyphenolic content and antioxidant capacity, and used as natural additive for food process control and food safety.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.