Objective: In this study, novel biological activities of Bougainvillea sp extracts related to their polyphenolic contents were investigated. Methods: Scavenging capacity assays against non-biological and biological radicals, and evaluation of total reduction capacity were evaluated spectrophotometrically. Colorimetric COX (ovine) inhibitor screening assay kit and U373 Cell have been used for evaluating of anti-inflammatory and antiproliferative effects of extracts. The Phenolic and flavonoid contents have been estimated by using Folin-Ciocalteu and AlCl3 methods respectively. Results: Butanolic and methanolic fractions of B. glabra have been biologically effective by showing significant radical scavenging abilities through the inhibition of ABTS+, DPPH and lipid peroxidation. Potentially, dichloromethane fractions a best presented antiproliferative effects with an IC50 of 21.72±1.57 ìgmL-1 and 25.56±2.55 ìgmL-1. In opposite all extracts exhibited a non significant inhibitory effect on the COX-2 while any inhibiting activity were observed with the COX-1 assay. The quantification of some polyphenolics revealed that ethyl acetate fraction of B. spectabilis and methanolic fraction of B. glabra have the highest similar phenolic contents with 133.88±1.56 mgGAEg-1 and 152.25 ± 2.17 mgGAEg-1 (p0.05) respectively. The same fractions showed the highest rate of flavonoid. The notified biological activities were supported the secondary metabolites found in different extracts. Conclusion: The results of these assays could justify partially the traditional uses of B. spectabilis and B. glabra for medical purpose.

Antioxidant activity Antiproliferative effect phenolics Bougainvillea spectabilis