Antioxidant Activities and Free Radical Scavenging Potential of Bauhinia microstachya (RADDI) MACBR. (Caesalpinaceae) Extracts Linked to Their Polyphenol Content

Abstract

Bauhinia belongs to the Caesalpinaceae, a plant family that comprises approximately 250 species.1) Native peoples from tropical regions use Bauhinia leaves and bark as medicine in infusions and other phytotherapic preparations. 2,3)Some native Bauhinia species in Brazil are known as "patade-vaca" (cow's hoof) and are widely used in folk medicine to treat various ailments, mainly infections and diabetes. Some reports have demonstrated positive effects on factors related to diseases and pathological states.2-5) Bauhinia microstachya (RADDI) MACBR. (Caesalpinaceae) is a creeper plant that occurs naturally in southern Brazil where is popularly known as "escada-de-macaco" (monkey's ladder). B. microstachya is often cultivated in small areas and its leaves are used as herbal antidiabetic medicine. Traditionally the leaf infusion or garrafada (a preparation with cachaça-the popular local sugar cane brandy-and leaves) is drunk after meals to help control blood sugar levels and other diabetic disorders. Phytochemical investigations with B. microstachya leaves have identified compounds such as steroidal glycosides, triterpenes, lactones and phenolic compounds, mainly flavonoids. [6][7][8] Plant phenolics form a large group of natural compounds, ubiquitous in the plant kingdom. It is known that these secondary metabolites display a remarkable array of biochemical interactions, probably due to antioxidant properties. 9)These substances may act as potent metal chelators and/or free radical scavengers, 10) however, it has been reported that the performance of these compounds in oxidative systems depends on activity-structure relationships.11,12) As an unfortunate consequence of aerobic life, free radicals and other reactive oxygen species (ROS) are formed by biological redox reactions.13) The role of free radicals reactions in biology and medicine has become an area of intense interest due to their relationship to chronic diseases.13) It is generally accepted that free radicals play an important role in the development of tissue damage and pathological events in living organisms.13) Lipids containing polyunsaturated fatty acids can be oxidized by free radical-mediated reactions. In addition, when oxygen is supplied in excess or their reduction is insufficient, this generates endogenous ROS imbalance with formation of hydroxyl ( · OH) and superoxide (O 2 · Ϫ ) radicals.13) In inflammation and endothelial damage, NO plays a major role as precursor of peroxynitrite (ONOO Ϫ ).14) If the endogenous response system, such as antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), is inadequate in scavenging ROS, damage to important macromolecules can be established and generate cellular oxidative stress.13) In addition, the non-enzymatic antioxidants (such as vitamin C, vitamin E and phenolic compounds found in a vegetable-rich diet) play a significant role in the physiological redox balance together with enzymatic defenses. 13)Considering the increasing interest in antioxidants, the potential antioxidant effects of pheno...

Bioassay‐guided Evaluation of Antioxidant and Antinociceptive Activities of Carvacrol

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“…TBARS (thiobarbituric acid reactive species) assay was employed to quantify lipid peroxidation [19], and an adapted TBARS method was used to measure the antioxidant capacity of CARV using egg yolk homogenate as lipid-rich substrate [18]. Briefly, egg yolk was homogenized (1% w ⁄ v) in 20 mM phosphate buffer (pH 7.4), 1 ml of homogenate was sonicated and then homogenized with 0.1 ml of CARV at different concentrations.…”

The influence of electron beam radiation in the nutritional value, chemical composition and bioactivities of edible flowers of Bauhinia variegata L. var. candida alba Buch.-Ham from Brazil

“…In another study, aqueous and hydroethanolic extracts of leaves of other species, Bauhinia microstachya (Raddi) Macbr. were evaluated for its antioxidant activity and both extracts revealed strong antioxidant activity, being the ethanolic extract the most effective one; and also a positive correlation was made between the activity and the phenolic content (Da Silva et al, 2007).…”

Glycemic Regulation and Cytotoxic Characteristics of the Ethyl Acetate Fraction from <em>Passiflora cincinnata</em> Mast Leaves

“…The total flavonois content was determined according to [55] with minor modifications. Briefly, 1 mL of the ExEt, F.MET and F.ACT at 100 μg.mL -1 was mixed with 1 mL of 2% aluminum trichloride and 2 mL of 0.5% sodium acetate.…”