Antioxidant Principles from Bauhinia tarapotensis

Abstract

A new cyclohexenone (1) and a new caffeoyl ester derivative (2), together with the known compounds (-)-isolariciresinol 3-alpha-O-beta-D-glucopyranoside (3), (+)-1-hydroxypinoresinol 1-O-beta-D-glucopyranoside (4), isoacteoside (5), luteolin 4'-O-beta-D-glucopyranoside (6), and indole-3-carboxylic acid (7), were isolated from the leaves of Bauhinia tarapotensis. The structures of these new compounds were determined by spectroscopic data analysis. The antioxidant activities of 1-7 were determined by measuring their free radical scavenging effects, using the 1,1-diphenyl-2-dipicrylhydrazyl free radical (DPPH) and Trolox equivalent antioxidant activity (TEAC) methods, and the coupled oxidation of beta-carotene and linoleic acid. Compounds 3-5 showed good activities in the DPPH and TEAC tests, while compounds 1 and 2 were active in the coupled oxidation of beta-carotene and linoleic acid bioassay.

Antioxidant and Nephroprotective Activities of Aconitum heterophyllum Root in Glycerol Induced Acute Renal Failure in Rats

“…Absorbance of controlabsorbance of test ×100 Percentage of inhibition = Absorbance of control dPPh Free Radical Scavenging Assay EEAHR was tested for free radical scavenging activity by the DPPH method of Braca et al, [29]. Free radical scavenging activity of the extract was held based on the scavenging activity of stable DPPH.…”

InVitro Antioxidant and Free Radical Scavenging Activity of Withania Somnifera Root

“…The free radical scavenging capacity of the extracts was determined using DPPH [19] . Freshly prepared DPPH solution was taken in test tubes and extracts were added followed by serial dilutions (15.625 μg/ml to 250 μg/ml) to every test tube so that the final volume was 5 ml and after 30 min, the absorbance was read at 517 nm using a spectrophotometer.…”

Microwave-assisted hydrodistillation of essential oil from rosemary

“…The free radical scavenging activity using DPPH radical was determined according to the method described by Braca et al (2001). In this experiment 50 μL of each extract was added to 950 μL of 0.030 mg/mL methanol solution of DPPH.…”

“…Then, the mixture was shaken vigorously and left in darkness for 5 min. Finally, the absorbance of the mixture was measured against methanol (blank) at 515 nm by using a spectrophotometer (Cary 50 Scan UV-Visible Spectrophotometer) The DPPH scavenging activity was expressed as the percent inhibition of free radical DPPH (Braca et al 2001). …”