Potencial antimicrobiano do ácido clorogênico: uma alternativa natural para a conservação de alimentos

Abstract

Considerando que a contaminação fúngica é a principal causa de deterioração alimentar e perdas econômicas, além de representar sérios riscos à saúde devido às micotoxinas e aos efeitos colaterais dos conservantes químicos sintéticos, objetiva-se desenvolver um método de biopreservação natural eficaz. O método proposto utiliza os compostos do grão de café verde (Coffea arabica), especificamente o Ácido Clorogênico (CGA) e a cafeína, que possuem notável potencial antifúngico. Para tanto, procede-se à extração aquosa do CGA de grãos verdes de café moídos. O extrato é então clarificado utilizando as Soluções de Carrez I e II, que removem interferentes (proteínas e polifenóis de alto peso molecular), purificando o CGA. A eficácia antifúngica é avaliada in vitro pela técnica de difusão em disco em placas de Potato Dextrose Agar (PDA). Fungos isolados de alimentos contaminados (pão, frutas e vegetais) são inoculados, e o extrato de CGA foi aplicado nos discos de papel filtro, com o intuito de observar a inibição do crescimento microbiano. De acordo com os resultados observados, é possível sugerir que o extrato aquoso / alcoólico do café verde demonstrou potencial antimicrobiano, sendo necessários estudos complementares futuros para aplicação como conservante alimentício natural.

Considering that fungal contamination is the main cause of food spoilage and economic losses, in addition to posing serious health risks due to mycotoxins and the side effects of synthetic chemical preservatives, the aim is to develop an effective natural biopreservation method. The proposed method uses compounds from the green coffee bean (Coffea arabica), specifically Chlorogenic Acid (CGA) and caffeine, which have notable antifungal potential. To this end, CGA is extracted aqueously from ground green coffee beans. The extract is then clarified using Carrez Solutions I and II, which remove interferents (proteins and high molecular weight polyphenols), purifying the CGA. Antifungal efficacy is evaluated in vitro using the disk diffusion technique on Potato Dextrose Agar (PDA) plates. Fungi isolated from contaminated foods (bread, fruits and vegetables) are inoculated, and the CGA extract was applied to filter paper discs, in order to observe the inhibition of microbial growth. To this end, CGA is extracted aqueously from ground green coffee beans. The extract is then clarified using Carrez Solutions I and II, which remove interferents (proteins and high molecular weight polyphenols), purifying the CGA. Antifungal efficacy is evaluated in vitro using the disk diffusion technique on Potato Dextrose Agar (PDA) plates. Fungi isolated from contaminated foods (bread, fruits and vegetables) are inoculated, and the CGA extract was applied to filter paper discs, in order to observe the inhibition of microbial growth. According to the results observed, it is possible to suggest that the aqueous / alcoholic extract of green coffee demonstrated antimicrobial potential, requiring additional future studies for application as a natural food preservative.