Bauhinia holophylla (Bong.) Steud. leaves-derived extracts as potent anti-dengue serotype 2.

Dengue virus (DENV) is the most prevalent mosquito-borne viral pathogen and made the disease a major health concern worldwide. However, specific antiviral drugs against this arbovirose or vaccines are not yet available for treatment or prevention. Thus, here we aimed to study the antiviral activity of hydroethanolic extract, fraction ethyl acetate and subfractions of the leaves of Bauhinia holophylla (Fabaceae:Cercideae), a native plant of the Brazilian Cerrado, against DENV-2 by methylthiazolyldiphenyl-tetrazolium bromide (MTT) method in mammalian cells culture. As results, the hydroethanolic extract showed the most potent effect, with an inhibitory concentration (IC50) of 3.2 µg mL-1 and selectivity index (SI) of 27.6, approximately 16-times higher anti-DENV-2 activity than of the ribavirin (IC50 52.8 µg mL-1). Our results showed in this study appointed that B. holophylla has a promising anti-dengue activity, which was associated mainly with the presence of flavonoids.

Validated spectrophotometric method for quantification of total triterpenes in plant matrices.

BACKGROUND: Triterpenes are ubiquitous secondary metabolites present in plants. They can be found in both forms, as genins or conjugated as glycosides. Although distinct analytical methods to quantify these compounds in vegetal tissues are available in the literature, limitations like high cost, complexity on sample preparation, and selectivity are often challenging issues. This study aimed to develop and to validate a simple and rapid spectrophotometric method to detect and quantify total triterpenes in plant matrices. METHODS: The assay was conducted directly into glass tubes using vanillin, acetic acid, and sulphuric acid as reagents, and ß-sitosterol as reference standard. The samples were analyzed at 548 nm assessing the quality parameters of selectivity, linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ), and robustness. RESULTS: The method was selective, with precision and accuracy varying from 0.56% to 4.98% and 96.63% to 113.87%, respectively. The values of the limit of detection and quantification were 0.042 µg.mL-1 and 0.14 µg.mL-1, correspondingly. The correlation coefficient (r) at the concentration range of 3.08 µg.mL-1to 24.61 µg.mL-1 was 0.9998. The total of triterpenes found in of B. holophylla and M. ilicifolia leaves were 132.36 ± 20.36 mg EßS.g-1 of dry extract and 53.91 ± 2.6 mg EßS.g-1 of dry extract, respectively. CONCLUSION: The method was reliable to quantify total triterpenes extracted from Maytenus ilicifolia and Bauhinia holophylla. Graphical abstract.

Effect of Bauhinia holophylla treatment in Streptozotocin-induced diabetic rats

ABSTRACT Bauhinia holophylla, commonly known as "cow's hoof", is widely used in Brazilian folk medicine for the diabetes treatment. Therefore, the aim of this study was at evaluating the aqueous extract effect of Bauhinia holophylla leaves treatment on the streptozotocin-induced diabetic rats. Diabetes was induced by Streptozotocin (40 mg/Kg) in female Wistar rats. Oral administration of aqueous extract of Bauhinia holophylla leaves was given to non-diabetic and diabetic rats at a dose of 400 mg/kg during 21 days. On day 17 of treatment, the Oral Glucose Tolerance Test was performed to determine the area under the curve. At the end of the treatment, the animals were anesthetized and blood was collected for serum biochemical parameters analysis. After treatment with Bauhinia holophylla extract, non-diabetic and diabetic rats presented no glycemic changes. On the other hand, the plant treatment decreased body weight and increased ALT and AST activities. In conclusion, the treatment with aqueous extract of B. holophylla leaves given to diabetic rats presented no hypoglycemic effect in nondiabetic animals and no antidiabetic effect in diabetic animals with the doses studied. In addition, the diabetic animals treated with the B. holophylla extract showed inconvenient effects and its indiscriminate consumption requires particular carefulness.