Quantificações de substâncias tânicas em Anadenanthera colubrina (Vell.) Brenan, Mimosa tenuiflora (Willd.) Poir. e Acacia mearnsii De Wild. utilizando distintas metodologias.

Abstract

The study aimed to evaluate and compare methodologies for quantifying tannic substances from solid materials of three tree species. We selected ten adult individuals angico-vermelho [Anadenanthera colubrina (Vell.) Brenan)] and ten jurema-preta [Mimosa tenuiflora (Willd.) Poir.], selected from the Cuncas Farm, municipality of Malta, Paraíba, which were assessed bark and green fruit. We still used black wattle bark acácia-negra (Acacia mearnsii De Wild.) Five individual trees of a forest stand located in the municipality of Pelotas, Brazil. For the method of formaldehyde we calculated moisture content, total solids, Stiasny index and content of condensed tannins. The results were interpreted by F test, compared with the Tukey test at 5% probability. Regarding the Stiasny index, Shells of the acacia-negra and jurema-preta did not differ statistically, averaging 68.3 and 62.6%, respectively. The content of condensed tannins (TTC) was higher for acacia negra bark, averaging 32.6%, and the jurema-preta and angico-vermelho howed 26.2 and 20.3%, respectively. The angico-vermelho fruits presented with average 20.2% skin. For powder method, we used 12.5g of crushed and graded particles, subjected to extraction using the extractor type shirt extraction vapor. This happened until 1000 ml of analytical solution was obtained. It was determined the moisture content, dry mass of the particles, total solids, soluble solids and tannin content. We held on mixtures of materials (bark and fruits) of all individuals of the same species and subsequently, we used a completely randomized design, with three species evaluated (jurema-preta and acácia-negra), totaling four treatments. Three replicates were evaluated (extractions) for treatment and all sub repetitions(moisture content, total solids, total soluble solids, soluble solids tannic etc.) were analyzed in triplicate and the results interpreted by F test, with mean comparison by Tukey test, considering 5% probability. For the bark of angico-vermelho and acácia-negra, skin powder method stood out due to the higher values of tannins when compared to the bark of jurema and fruit angico. However, it is observed that the acácia-negra and angico do not statistically differ. Skin powder method was efficient as the tannin content obtained from angico-vermelho bark as it did not differ statistically from the acacia-negra wattle. However, additional studies are required in order for a better evaluation of this property.