In the present study, a multiple approach was used to characterize Malpighia punicifolia extract and to evaluateits inhibitory activity against several meat spoilage bacteria. First, volatile fraction, vitamins and phenolic compounds ofthe extract obtained by supercritical fluid extraction were determined by GC-MS and HPLC. Then, the antimicrobialaction of the extract was in vitro evaluated against Pseudomonas putida DSMZ 291T, Pseudomonas fluorescens DSMZ50009T, Pseudomonas fragi DSMZ 3456T,andBrochothrix thermosphacta DSMZ 20171Tby the agar well diffusion assayand by the agar dilution test. Based on the results of the minimum inhibitory concentration (MIC) against the assayedbacteria, 4 different concentrations of the extract were used in a challenge test on water buffalo steaks stored for21 d at 4 °C. Results of chemical analyses showed that M. punicifolia extract is characterized by the presence of severalcompounds, already described for their antimicrobial (phenolic acids, flavonones, and furanes) and antioxidant (ascorbicacid) properties. The in vitro detection of antimicrobial activities highlighted that the extract, used at 8% concentration,was able to inhibit all the target bacteria. Moreover, very low MIC values (up to 0.025%) were detected. In situ tests,performed on water buffalo steaks treated with the extract in the concentration range 0.025% to 0.05%, showed a stronginhibition of both intentionally inoculated bacteria and naturally occurring microorganisms. Positive results, in terms ofcolor and odor, were also observed during the entire storage of steaks preserved with the extract.
Antimicrobial effect of Malpighia punicifolia and extension of water buffalo steak shelf-life
TREMONTE, Patrizio;SORRENTINO, Elena;SUCCI, Mariantonietta;TIPALDI, LUCA;PANNELLA, GIANFRANCO;COPPOLA, Raffaele
2016-01-01
Abstract
In the present study, a multiple approach was used to characterize Malpighia punicifolia extract and to evaluateits inhibitory activity against several meat spoilage bacteria. First, volatile fraction, vitamins and phenolic compounds ofthe extract obtained by supercritical fluid extraction were determined by GC-MS and HPLC. Then, the antimicrobialaction of the extract was in vitro evaluated against Pseudomonas putida DSMZ 291T, Pseudomonas fluorescens DSMZ50009T, Pseudomonas fragi DSMZ 3456T,andBrochothrix thermosphacta DSMZ 20171Tby the agar well diffusion assayand by the agar dilution test. Based on the results of the minimum inhibitory concentration (MIC) against the assayedbacteria, 4 different concentrations of the extract were used in a challenge test on water buffalo steaks stored for21 d at 4 °C. Results of chemical analyses showed that M. punicifolia extract is characterized by the presence of severalcompounds, already described for their antimicrobial (phenolic acids, flavonones, and furanes) and antioxidant (ascorbicacid) properties. The in vitro detection of antimicrobial activities highlighted that the extract, used at 8% concentration,was able to inhibit all the target bacteria. Moreover, very low MIC values (up to 0.025%) were detected. In situ tests,performed on water buffalo steaks treated with the extract in the concentration range 0.025% to 0.05%, showed a stronginhibition of both intentionally inoculated bacteria and naturally occurring microorganisms. Positive results, in terms ofcolor and odor, were also observed during the entire storage of steaks preserved with the extract.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
