Antioxidant activity and enzyme inhibitory potential of Euphorbia resinifera and E. officinarum honeys from Morocco and plant aqueous extracts

Abstract

Natural products may be applied in a wide range of domains, from agriculture to food and pharmaceutical industries. In this study, the antioxidant properties and the capacity to inhibit some enzymatic activities of Euphorbia resinifera and Euphorbia officinarum aqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected in E. officinarum honey, which may indicate environmental pollution around the beehives or inadequate storage of honey samples. This honey sample showed higher amounts of total phenols and better capacity for scavenging superoxide anion free radicals and DPPH free radicals as compared with E. resinifera honey, but poorer capacity for inhibiting lipoxygenase, acetylcholinesterase, tyrosinase and xanthine oxidase. The ratio plant mass:solvent volume (1:100) and extraction time (1 -2 h) were associated with higher total phenols and better antioxidant activities and lipoxygenase, acetylcholinesterase and tyrosinase inhibitory activities, regardless of the plant species. The aqueous extracts had systematically higher in vitro activities than the respective honey samples.

Comparative Study of the Antioxidant and Enzyme Inhibitory Activities of Two Types of Moroccan Euphorbia Entire Honey and Their Phenolic Extracts

“…The total polyphenol content in honey as well as in the methanolic extract were determined as stated by Boutoub et al [13]. The total polyphenol content was expressed as mg gallic acid equivalents per 100 g (mg GAE/100 g).…”

“…Free radical scavenging activity determination by DPPH scavenging activity was performed as described by Boutoub et al [13]. The volumes used for phenolic extract and honey samples were 25 and 200 µL, respectively.…”

“…The nitric oxide (NO) scavenging activity was carried out according to Boutoub et al [13]. In both phenolic extract and honey sample the volume used was 150 µL.…”

“…Scavenging ability of superoxide anion radical was assayed as reported by Boutoub et al [13]. In both phenolic extract and honey sample the volume used was 25 µL.…”

“…Anti-inflammatory, analgesic and antimicrobial properties have been attributed to Euphorbia honeys along with the ability to promote wound healing, nevertheless, the majority of works has been focused on the anti-microbial activity [9][10][11], and much less, antioxidant activity [12]. More recently, our team compared the antioxidant activity and some enzyme inhibitory activities of Euphorbia officinarum, E. resinifera plants with those of the respective two monofloral honeys [13]. This work permitted detected relative high amounts of Al, Cu and Fe in E. officinarum honey, suggesting environmental pollution and/or inadequate storage of honey.…”