Avaliação microbiológica de extratos de Camu-Camu Myrciaria Dubia H.B.K (Mcvough) e Jabuticaba (Myrciaria Cauliflora) com posterior desenvolvimento de membranas de quitosana

Abstract

Skin lesions represent a disease that, at a certain period of life, all human beings will suffer, be it cuts, scrapes, burns or ulcers. Because of this, there is a need to create accessible resources for the population, using renewable, low-cost and easy-to-obtain raw materials. Chitosan is a biocompatible and biodegradable polysaccharide, which has antimicrobial and healing properties, which is why it is promising for use in the manufacture of biomaterials. The first step of this study was to obtain different extracts of the Myrtaceae family, the camu-camu (Myrciaria dubia H.B.K (McVough)) and jabuticaba (Myrciaria cauliflora). The extracts were obtained by maceration, varying the extraction times, between 12 and 24 hours, and also the solvents of the extracting solution, namely: 100% water, 70 % ethanol (EtOH) in water and 100% EtOH. The extracts were evaluated for their antimicrobial activities against 4 bacteria (Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Listeria monocytogenes) using the disk agar diffusion test. After the tests, it was decided to make the films with 100 % ethanolic extracts of jabuticaba and 70 % ethanol in the water of camu-camu because they showed promising results regarding the inhibition of halos with the four microorganisms. In the second stage of the research, the films were prepared by the solvent evaporation method (casting), varying the concentrations of the extracts in 0.5 % mass/volume (m/v), 1.0 % (m/v) and 1.5 % (m/v), where they were evaluated for their macroscopic characteristics, degree of swelling and antimicrobial activity. The films showed flexibility, absence of bubbles, and characteristic coloration of the extracts with intensity varying according to their concentration in the membranes. Except for the films with 0.5 % and 1.5 % of jabuticaba extract, all the others showed swelling ranging from 150 to 600 % in the first 60 minutes, and after that, they showed a mass loss, which may be indicative of membrane dissolution. Concerning the results of the antimicrobial tests of the films for the four strains, all showed inhibition of growth on the disc, however, the film with the incorporation of 0.5 % of the camu-camu extract against the strain of S. aureus showed the best halo inhibition, with 15.3 cm.