Total phenolic contents, antioxidative activity and inhibitory on effect matrix metalloproteinase-2 and -9 of ethanolic extract from Thai flowers

Abstract

Introduction: The present study aimed to investigate the total phenolic content, antioxidant activity and MMP-2 and -9 inhibitory effect in fibroblast cell of ethanolic extracts from flowers of Lagerstroemia floribunda and Lagerstroemia speciosa. Materials and Methods: The powders of Thai flowers were extracted by 50% ethanol then the total phenolic contents were determind by the Folin-Ciocalteu method. The antioxidant activity including 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging and ferric reducing power (FRAP) were examined. The inhibitory effect on fibroblast MMP-2 and MMP-9 was measured by gelatin zymography. Results: The extract of L. floribunda and L. speciosa gave total phenolic content at 418.50±39.69 and 636.74±44.14 mg gallic acid equivalent (GAE)/g of the extracts. They show the high antioxidative activities with IC₅₀ values of 4.31±0.10 and 3.89±0.12 µg/ml and FRAP values at 1.21±0.28 and 1.79±0.26 mg Fe²⁺/mg. Moreover, the flower extracts inhibited MMP-2 and MMP-9 activities 50% inhibition concentrations on MMP-2 and MMP-9 of L. floribunda were 953.07 and 771.07 ppm and 634.60 and 548.40 ppm of L. speciosa. Conclusion: The results of this study indicated that ethanolic extract of L. floribunda and L. speciosa have high inhibitory effect on MMP-2 and MMP-9 with high antioxidative activity. Therefore, these Thai flowers may be good sources for natural antioxidant products for anti-aging agent.