Role of the flavonoid-rich fraction in the antioxidant and cytotoxic activities of Bauhinia forficata Link. (Fabaceae) leaves extract

Abstract

Bauhinia forficata Link. is utilised as an antidiabetic in Brazilian folk-medicine; furthermore, its antioxidant properties suggest a potential usefulness in the prevention of diabetes complications associated with oxidative stress. The contribution of a flavonoid-rich fraction (FRF), HPLC-PDA-ESI-MS characterised, to the antioxidant and cytotoxic properties of B. forficata hydro-alcoholic leaves extract was evaluated for the first time. Both extract and FRF showed radical-scavenging activity and reducing power with a strong relationship with the flavonoid content found; hence, flavonoids are mainly responsible for the primary antioxidant activity of B. forficata extract. The extract significantly decreased FO-1 cell viability at the higher concentrations. FRF did not exert any effect; thus, flavonoids do not appear to be responsible for the cytotoxicity of the extract. The extract resulted virtually non-toxic against both Artemia salina and normal human lymphocytes, demonstrating potential selectivity in inhibiting cancer cell growth. Finally, no antimicrobial activity was observed against the bacteria and yeasts tested.

Influence of Prostanoids in the Diuretic and Natriuretic Effects of Extracts and Kaempferitrin from Bauhinia forficata Link Leaves in Rats

“…Several scientific investigations have explored the biological properties of B. forficata , demonstrating, in addition to the hypoglycemic activity already mentioned in the section, its potential effect as an antioxidant (Miceli et al, ; Salgueiro et al, ), an anticoagulant, an antifibrinogenolytic against snake venoms (Oliveira et al, ), and now for the first time as shown here in our study, as a diuretic agent. Moreover, as described in the following paragraphs, kaempferitrin, the major natural constituent isolated from B. forficata leaves, also demonstrated the diuretic and natriuretic properties when given to rats, adding to their biological effects already described in previous studies, which showed their beneficial effect in the prevention of bone loss in ovariectomized rats (Ma et al, ), the stimulation of glucose uptake in skeletal muscle (Cazarolli et al, ) and an antidepressant‐like effect (Cassani et al, ).…”

Chemical Characterization and Biological Activities of Phenolic‐Rich Fraction from Cauline Leaves of Isatis tinctoria L. (Brassicaceae) Growing in Sicily, Italy

“…In this work, the characterization of the phenolic profile of ItJ‐EAF was attained by HPLC‐PDA/ESI‐MS analysis. Identification was carried out by the complementary information provided by chromatographic retention times, PDA and mass spectra, and further supported by comparison to existing literature data on the same species and other vegetable extracts …”

“…The condensed tannins of ItJ‐EAF were determined according to a previously reported method . An aliquot of the sample solution (50 μl) was mixed with 1.5 ml of 4% vanillin in MeOH and then 750 μl of concentrated HCl were added.…”

“…The total flavonoid content of ItJ-EAF was determined by using the aluminum chloride (AlCl 3 ) colorimetric assay. [18] An aliquot of appropriately diluted sample solution (0.5 ml) was mixed with 1.5 ml MeOH, 0.1 ml of 10% AlCl 3 , 0.1 ml of 1M AcOK, and 2.8 ml of distilled water. After incubation at r.t. for 30 min, the absorbance of the mixture was spectrophotometrically measured at 415 nm.…”

The antiulcer and antioxidant mechanisms of the butanolic fraction extract obtained from Bauhinia forficata leaves: A medicinal plant frequently used in Brazilian folk medicine

“…Among the wide range of plant species we investigated B. forficata Link (Caesalpinioideae) for the evaluation of gastric antiulcer activity, popularly known in Brazil as "Unha-de-Vaca", "Pata-de-Vaca" and "Casco-de-Vaca", B. forficata is a small tree, native to the tropical areas of Asia, Paraguay and Argentina; this vegetal species is well-adapted to the Brazilian climate (Miceli et al, 2016). B. forficata is used in popular medicine in Brazil.…”