ABSTRACT
The use of medicinal plants for disease prevention, treatment and cure is an ancient practice used by humanity, and many plants species are used in bioprospecting research. In this context, its stands out Eugenia uniflora L., populary known as pitangueira and belongs to the Myrtaceae family, with a wide geographic distribution and native of Brazil. In view of the therapeutic qualities of the plant and the lack of the studies on its seeds, the present study had as objective to evaluate the phytochemical profile of the extracts of Eugenia uniflora L. seeds, from different solvents, as well as their antibacterial activity, antioxidant and its inhibitory effect of intestinal disaccharidases. Results showed a high content of phenolic compounds and total flavonoids, thus characterizing antioxidant activity, also highlighting the best bacteriostatic action for the Gram positive strain of Staphylococcus aureus in the ethanolic fraction. Regarding the disaccharidases, a strong inhibitory action was observed for all concentrations, evidencing a antihyperglycemic potential. The present research allowed to concluded that Eugenia uniflora L. seeds have promising biological activities for the industrial sector, but a more detailed investigation is needed regarding their bioactive compounds.
A utilização de plantas com fins medicinais para prevenção, tratamento e cura de doenças é uma prática antiga utilizada pela humanidade, sendo que muitas espécies vegetais são usadas para a pesquisa da bioprospecção. Neste contexto, destaca-se a Eugenia uniflora L., conhecida popularmente como pitangueira e pertencente à família Myrtaceae, com ampla distribuição geográfica e nativa do Brasil. Diante das qualidades terapêuticas da planta e a falta de estudos sobre suas sementes, o presente trabalho teve como objetivo avaliar o perfil fitoquímico dos extratos das sementes de Eugenia uniflora L. a partir de diferentes solventes, bem como sua atividade antibacteriana, antioxidante e seu efeito inibidor de dissacaridases intestinais. Os resultados mostraram um alto teor de compostos fenólicos e flavonóides totais, caracterizando a atividade antioxidante, destacando também a melhor ação bacteriostática para a cepa Gram positiva de Staphylococcus aureus na fração etanólica. Em relação às dissacaridases, uma forte ação inibitória foi observada para todas as concentrações, evidenciando um potencial anti-hiperglicêmico. A presente pesquisa permitiu concluir que as sementes de Eugenia uniflora L. apresentam atividades biológicas promissoras para o setor industrial, mas é necessária uma investigação mais detalhada de seus compostos bioativos.
Subject(s)
Seeds , Disaccharidases/antagonists & inhibitors , Eugenia/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Plants, Medicinal/chemistry , Brazil , Plant Extracts/pharmacologyABSTRACT
Tannic acid is a glucoside (penta-m-digallolyl-glucose), which exhibits a wide variety of physiological functions. Around neutral pH, 0.4 mM tannic acid produced 84% inhibition of rat brush border sucrase activity, but 35-40% enzyme inhibition was observed in the rabbit intestine at 0.08 mM concentration. In the mice, 74-77% enzyme inhibition was observed at 0.05 mM concentration of tannic acid. The observed inhibition was reversible in rat intestine. Tannic acid (0.2 mM) also inhibited lactase (18% in adult and 71% in suckling animals), maltase (76%) and trehalase (88%) activities in rat intestine. pH versus activity curves showed that 0.2 mM tannic acid inhibited enzyme activity in rat by 91% at pH 5.5 which was reduced to 14% at pH 8.5 compared to the respective controls. In the rabbit 18-60% enzyme inhibition was noticed below pH 7.0, however at pH 8.5, it was of the order of 38%. Kinetic analysis revealed that tannic acid is a competitive inhibitor of rat brush border sucrase at pH 6.8. Effect of tannic acid together with various -SH group reacting reagents revealed that the enzyme inhibition is additive in nature, suggesting the distinct nature of binding sites on the enzyme for these compounds. The results suggest that tannic acid is a potent inhibitor of intestinal brush border disaccharidases, and could modulate the intestinal functions.
Subject(s)
Animals , Disaccharidases/antagonists & inhibitors , Intestines/drug effects , Mice , Mice, Inbred BALB C , Microvilli/drug effects , Rabbits , Rats , Rats, Wistar , Tannins/pharmacologyABSTRACT
Studies have been done on the effect of Penicillin, Streptomycin and Isonicotinic Acid hydrazide on small intestinal oligosaccharidase and it was observed that the drug penicillin inhibited the enzyme lactase and sucrase by 62.7% and 34.7% respectively, whereas I.N.H. inhibited the enzyme sucrase and maltase by 57.1% and 56.14% respectively. Streptomycin did not show any inhibitory effect on those enzymes. Lactose tolerance test showed impairment of lactose absorption in case of penicillin. Fasting serum sugar level was diminished both in penicillin and streptomycin and the absorption capacity was increased after oral administration of streptomycin.