Controle de qualidade e atividade antimicrobiana de extratos da própolis vermelha de Alagoas comercializados em Maceió

Abstract

Propolis is a substance of complex composition, with a gummy and balsamic aspect, rich in phenols and flavonoids. The growing search for natural products as an alternative to allopathic medicines, made the red propolis from Alagoas a product coveted by many, due to the biological activity derived from its chemical constituents. In this sense, the high consumption triggered the increase of producers, as well as, of this product in the market, hindering the work of the inspection agencies. Thus, the objective of this work was to carry out the quality control of red propolis extracts sold in Maceió - AL, as well as to evaluate their antimicrobial activity. The hydroalcoholic extracts of PV (A, B, C, D and E) were purchased from establishments that sell natural products. The quality control of the extracts was carried out in terms of organoleptic aspects, soluble solids content and pH. The phytochemical profile was evaluated by colorimetric methods determining phenols, total flavonoids and antioxidant activity by the Folin-Ciocaulteau methods, aluminum chloride such and DPPH radical, respectively. The absorption spectrum (UV-vis) of the extracts was obtained in the range of 200 to 500nn. The antimicrobial evaluation was evaluated against Staphylococcus aureus, Enterococcus faecalis, Staphylococcus epidermidis, Pseudomonas aeroginosa, Escherichia coli and Enterobacter cloacae. It was noted that only three, PVC, PCD and PVE were registered, of which only PVE had a dry extract content of 11% according to MAPA's guidance. The pHs of the samples showed a variation from 4.21 to 4.8. The determination of total phenols revealed an amount of 120.3 mgEAG.g-1 to 210.4 mgEAG.g-1 for PVA and PVB, respectively. For total flavonoids, there was a variation from 27.1 mgEQ.g-1 to 118 mgEQ.g-1 for PVA and PVC, respectively, in accordance with current legislation. The determination of antioxidant activity revealed that at a concentration of 1 μg/mL, PVA and PVE did not show any significant difference between themselves, inhibiting only 4.6% ± 2.20% and 6.5% ± 0.62%, respectively. Again, the PVA obtained a lower performance, inhibiting the concentration of 40 μg/mL, only 65.4% ± 1.57%. PVC demonstrated 50% inhibition of the DPP radical at a concentration of 13.18 μg/mL. In the spectrum, the samples showed a peak in the range of 290 to 295 nm corresponding to the flavonoids and phenols present in the structures of the flavonoids. The lowest minimum inhibitory concentrations belonged to PVC, PVD and PVE, where they inhibited E. coli and S. aureus by 15.625 μg/mL. In view of the above, it appears that all samples performed well, considering that the values are in accordance with MAPA, but PVE stood out from the others because it was the only one with a dry extract content of 11 %, having performed well in antioxity activity and having obtained the lowest MIC against more than one bacterium.