ABSTRACT
Honeys can be classified as polyfloral or monofloral and have been extensively studied due to an increased interest in their consumption. There is concern with the correct identification of their flowering, the use of analyses that guarantee their physicochemical quality and the quantification of some compounds such as phenolics, to determine their antioxidant and antimicrobial action. This study aims at botanical identification, physicochemical analyses, and the determination of total polyphenols, chromatographic profile and antiradical and antimicrobial activity of honey from different regions of Minas Gerais. Seven different samples were analyzed for the presence of pollen, and color determination. The physicochemical analyses performed were total acidity, moisture, HMF, reducing sugar, and apparent sucrose. The compound profile was determined by UHPLC/MS, the determination of total phenolics and antiradical activity (DPPH method) were performed by spectrophotometry, and minimum inhibitory and bacterial concentrations were determined for cariogenic bacteria. All honey samples met the quality standards required by international legislation, twenty compounds were detected as the main ones, the polyfloral honey was the only honey that inhibited all of the bacteria tested. Sample M6 (Coffee) was the one with the highest amount of total polyphenols, while the lowest was M4 (Cipó-uva). Regarding the antioxidant activity, M5 (Velame) had the best result and M4 (Cipó-uva) was the one that least inhibited oxidation. Of the polyfloral honeys, there was not as high a concentration of phenolic compounds as in the others. Coffee, Aroeira, Velame and Polyfloral have the best anti-radical actions. Betônica, Aroeira, Cipó-uva and Pequi inhibited only some bacteria. The best bacterial inhibition results are from Polyfloral.
ABSTRACT
This study was carried out with the objective of determining the antioxidant properties and quantification of total phenolics and flavonoids in relation to quercetin and rutin in some of the monofloral honeys produced in Minas Gerais (Brazil). In this study, 15 monofloral honey samples were obtained from different geographic regions of Minas Gerias, Brazil. The honeys were obtained from Cooperative of Beekeepers and Family Farmers of Northern Minas. To determine the antioxidant properties of honey samples, the test methods of total phenolic content, flavonoids (rutin and quercetin) and DPPH were used. As a result of the analysis of phenolic and flavonoid contents, the samples with the best results were A1-Aroeira and A4-Assa peixe. In antioxidant activity, the honey with the best EC50 results was A6-Aroeira. Differences between the antioxidant activities of the honey samples were found significantly (p< 0.01).
Subject(s)
AntioxidantsABSTRACT
Leaves of Anacardium humile are used in Brazilian traditional medicine for the treatment of intestinal disturbances and skin lesions. This study aimed to define leaf diagnostic structural characters, to propose a new method of phytochemical analysis of secretions, prospect flavonoids and alkaloids, and to evaluate their inhibitory activity on Candida albicans. Common anatomical, phytochemical, and microbiological methods were used. Leaves of Anacardium occidentale were used as a reference for the structural analyses. The main structural characters were closed vascular system, absence of ducts at the medulla, bilateral mesophyll, absence of bundle sheath extension, and secretory idioblasts at the xylem. The ducts present schizogenous origin, and secreting activity is restricted to the initial phases of leaf blade expansion. The proposed new phytochemical method is practical and inexpensive and has potential for wide application. The abundance of tannins and flavonoids is related to medicinal use. A single peak in high-performance liquid chromatography indicated the presence of a pure substance not previously reported. The extract had a strong inhibitory effect on C. albicans. The obtained results confirm the potential of A. humile for the prospection of new bioactive compounds.
ABSTRACT
Five (-)-cubebin derivative compounds, (-)-O-acetyl cubebin (3), (-)-O-benzyl cubebin (4), (-)-O-(N,N-dimethylaminoethyl)-cubebin (5), (-)-hinokinin (6) and (-)-6,6'-dinitrohinokinin (7), previously synthesised by our research group, were evaluated on in vitro assay against free amastigote forms of Trypanosoma cruzi, the asogic agent of Chagas' disease. It was observed that 6 was the most active compound (IC(50)=0.7 microM), and that 4 and 5 displayed moderate activity against the parasite, giving IC(50) values of 5.7 and 4.7 microM, respectively. In contrast, it was observed that compound 3 was inactive and that 7 displayed low activity with IC(50) values of congruent with 1.5 x 10(4) and 95.3 microM, respectively.
