Dados do Trabalho

Título

EVALUATION OF ANTIMICROBIAL POTENTIAL AND TOTAL PHENOLIC COMPOUNDS OF FRUIT EXTRACTS

Introdução

The study of natural compounds present in Brazilian plants with antimicrobial potential is one of the alternatives to replace the use of chemical preservatives and avoid antibiotic resistance. With this aim, the antimicrobial potential and quantification of total phenolics of six fruit extracts were evaluated: strawberry, jabuticaba, açaí, juçara, raspberry and blueberry.

Material e Métodos

The extraction was carried out by weighing the fresh fruit in an Erlenmeyer flask and adding 80% ethyl alcohol in a proportion of 1:10. After weighing, the Erlenmeyer flasks were placed in the ultrasound in a water bath for 50 minutes, at a frequency of 45 kHZ, power of 50% and temperature of 40 ºC. The solid part was discarded and the liquid part was centrifuged at 5000 rpm for 20 minutes. The supernatant was rotary evaporated, sterilized using a 0.22 µm membrane and frozen until use

Resultados e Discussão

Three pathogenic microorganisms, Escherichia coli ATCC 11229, Salmonella enteritidis ATCC 13076 and Staphylococcus aureus ATCC 25923 were incubated in BHI broth at 35 ºC for 24 hours. Then, pathogenic cultures (100 µL), extracts (100 µL) and double concentration BHI broth (100 µL) were added to a 96-well Elisa plate. This plate remained incubated for 24 hours at 35 ºC in an Elisa reader and Multiskan skyhigh microplate photometer – Termo Fisher Scientific, readings were taken every 2 hours at an absorbance of 600 nm. The results showed that the juçara extract showed a greater reduction in the growth of E. coli and Salmonella enteritidis by 65 % and 68 % respectively. S. aureus growth was reduced by 71% by jabuticaba extract. Total phenolic contents were obtained using the gallic acid standard curve and readings were taken on a spectrophotometer at 760 nm. The results expressed in gallic acid were: 7.3 mg/100 g for strawberry, 20.8 mg/100 g for jabuticaba, 5mg/100 g for raspberry, 9.2 mg/100 g for açaí, 6.5mg/100 g for juçara and 8.4 mg/100 g for blueberries

Conclusão

This study demonstrated that fruit extracts have antimicrobial potential against the pathogenic microorganisms tested. Other analyzes such as minimum inhibitory concentration and inhibitory active ingredient are underway to elucidate the inhibition mechanism.