Bioactive Metabolites from Cnidoscolus souzae and Acmella pilosa

Abstract

The bioassay-guided purification of the ethanol extracts of Acmella pilosa and Cnidoscolus souzae, two plants of the native flora of the Yucatan Peninsula used in traditional medicine to treat inflammation and pain, resulted in the identification of rosmarinic acid (1) and caffeic acid (2) as the bioactive metabolites from A. pilosa, and of 7-deoxynimbidiol (4) as the major bioactive metabolite from C. souzae. Metabolites 1, 2, and 4 proved to be responsible for the antioxidant activity originally detected in the corresponding organic crude extracts; 7-deoxynimbidiol (4) showed good analgesic and anti-inflammatory activities, inhibiting the pain induced by PGE2 and reducing the edema induced by carrageenan, respectively.

Antioxidant Metabolites from the Stems of Bakeridesia gaumeri

“…The moderate antioxidant activity (EC 50 = 0.85 ± 0.06 mM) of 7hydroxycadalenal (1), when compared to that of the ascorbic acid (positive control, EC 50 = 0.28 ± 0.02 mM), and its presence as a minor component in both the crude extract and the low polarity fraction, suggests that the contribution of this metabolite to the antioxidant activity of the stem crude extract is limited. However, the strong antioxidant activity of trans-clovamide (2) (EC 50 = 0.15 ± 0.01 mM), which is similar to that reported for rosmarinic acid (EC 50 = 0.15 mM) [12], and the fact that this metabolite is the major bioactive component in both the crude extract and the medium polarity fraction, suggests that 2 contributes to a great extent to the strong antioxidant activity of the stem crude extract. These results are in agreement with reports of 2 being the most active polyphenol isolated from Theobroma cacao, when tested for antioxidant activity in the linoleic acid oxidation, erythrocyte ghost system, and microsomal lipid peroxidation assays [13].…”

Constituents of Mediterranean Spices Counteracting Vascular Smooth Muscle Cell Proliferation: Identification and Characterization of Rosmarinic Acid Methyl Ester as a Novel Inhibitor

“…Rosmarinic acid methyl ester (RAME; 4 ) and caffeic acid methyl ester (CAME; 5 ) were obtained as by‐products in the purification process . Caffeic acid ( 2 ) was isolated from the ethanol extract of the stems of Acmella pilosa R.K. Cansen (Asteraceae) . Trans ‐clovamide ( 6 ) was obtained from the ethanol extract of the stems of Bakeridesia gaumeri (Standl.)…”

Antiproliferative activity of Haematoxylum brasiletto H. Karst

“…Chromatograms were examined under UV light and then visualized by dipping the plates in a solution of phosphomolybdic acid (20 g) and ceric sulfate (2.5 g) in 500 mL of sulfuric acid (5%), followed by drying and heating to 100°C. [ 14 ]…”