20 research outputs found
Thermal And Structural Study Of A Perovskite Layer [NH3 (CH2)3 - COOH] CdCl4
In this paper we present a study of a Phase Change Material type Perovskite Layerwhich have solid-solid transitions and thermal properties suitable for Thermal EnergyStorage. Structural study shows that organic chain in this organic-inorganic compoundpresents “trans” and “gauche” conformations due to the acid function. DSC studyshows three transitions with the increasing of temperature due to the change ofconformations in the organic chain.PCM, TES, Perovskite Layer, phase transitions, conformations, DSC
Antioxidant activity and enzyme inhibitory potential of Euphorbia resinifera and E. officinarum honeys from Morocco and plant aqueous extracts
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 ofEuphorbia resiniferaandEuphorbia officinarumaqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected inE. officinarumhoney, 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 withE. resiniferahoney, 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.FCTPortuguese Foundation for Science and TechnologyEuropean Commission [UID/MAR/00350/2020]info:eu-repo/semantics/publishedVersio
Physicochemical characterization and antioxidant activity of 17 commercial Moroccan honeys
In this study, 17 commercial honey samples from Morocco were analyzed. Four samples did not meet the international physicochemical standards due to high hydroxymethylfurfural content and low diastase activity. Phenol content varied from 163.82mg gallic acid equivalent (GAE)/kg in citrus honey to 923.70mg (GAE)/kg in thyme honey from Rachidia; flavonoid content ranged from 4.26mg quercetin equivalent (QE)/kg in citrus honey to 139.62mg QE/kg in black cumin honey. Black cumin honey had the highest peroxyl scavenging activity; oregano (from Zaraphyt) and thyme honeys (from Rachidia) had the highest ABTS (2,2'-azino-bis[ 3-ethylbenzothiazoline-6-sulphonic acid]) scavenging activity; and thyme honey (Saouira) had the highest NO scavenging capacity. The antioxidant activity of Moroccan honeys was correlated with the phenol, flavonoid, and melanoidin contents. Dark honeys had higher antioxidant activity than light honeys. Samples with high sodium levels had lower free radical scavenging activity. On the other hand, calcium and magnesium increased the ABTS and peroxyl scavenging capacity, respectively, of honey samples. According to cluster and discriminant analyses, the honey samples were grouped in three clusters with respect to the phenol, flavonoid, melanoidin, proline, mineral and sugar contents, and free radical scavenging capacity