RESUMO
This study aimed to evaluate the chemical composition and antioxidant activity of phenolic extracts from monofloral and polyfloral honey samples obtained from different Brazilian regions. The chemical composition (total content of phenolic compounds and flavonoids) of extracts were measured by using colorimetric assays and analyzed by high performance liquid chromatographic (HPLC-DAD). The antioxidant activity was evaluated by chemical and biochemical assays (reducing power assay, 1,1-diphenyl-2-picrylhydrazyl (DPPHâ ) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTSâ +) scavenger assays. It was also investigated the ability of extracts in attenuate lipid peroxidation induced by Fe2+ in phospholipids. The obtained results clearly demonstrated that the botanical origin and geographical region of honey collection influenced the chemical composition and antioxidant activity of extracts. Furthermore, the samples were constituted by phenolic acids and flavonoids, which p-coumaric acid was predominant among the compounds identified. All samples were able to scavenge free radicals and inhibit lipid peroxidation, and good correlations were obtained between the flavonoid content and honey color. In conclusion, the obtained extracts were constituted by antioxidant compounds, which reinforce the usage of honey in human diets, and demonstrated that the region of honey collection strong influenced in the chemical composition and, consequently, its biological effect.
Assuntos
Antioxidantes , Mel , Peroxidação de Lipídeos , Fenóis , Mel/análise , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fenóis/farmacologia , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/análise , Brasil , Peroxidação de Lipídeos/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Flavonoides/farmacologia , Flavonoides/química , Flavonoides/análise , Flavonoides/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Picratos/antagonistas & inibidores , Flores/química , Benzotiazóis/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidoresRESUMO
Trace and minor elements in Brazilian honey were analyzed by total reflection X-ray fluorescence spectroscopy. Up to 12 elements (K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br, and Sr) were detected in 160 samples of honey from 4 regions of Rio de Janeiro State (Barra Mansa, Teresópolis, northern and southern Nova Friburgo). The results showed the samples from Teresópolis had higher rates of essential and nonessential elements than samples from the other regions, except for Ni. K and Ca were the most abundant elements in all samples, in the range of 116.5 to 987.0 µg g(-1) . Ni, Cu, Zn, Se, and Sr were identified in small concentrations (0.01 to 12.08 µg g(-1) ) in all samples, indicating a low level of contamination in all the regions.