Zaahira Aumeeruddy-Elalfi

Euphorbia denticulata Lam.: A promising source of phyto-pharmaceuticals for the development of novel functional formulations.

In this study, Methanolic extracts of Euphorbia denticulata parts (flowers, leaf, stem, and mix of aerial parts) were assessed for a panoply of bioactivities. Inhibitory potential against key enzymes involved in diabetes (α-glucosidase and α-amylase), obesity (pancreatic lipase), neurodegenerative diseases (cholinesterases), and hyperpigmentation (tyrosinase) was evaluated. The antioxidant and antibacterial properties were also assessed. The total phenolic, flavonoid, and phytochemical profile were established using HPLC/DAD and molecular modelling studies on specific target compounds were performed in silico. The flower extract was found to be rich in phenolics and flavonoids, (60.11±1.40mgGAE/g and 42.04±0.16mgRE/g respectively), which tend to correlate with the high radical scavenging activity of this extract (120.34±3.33mgTE/g and 165.42±2.16mgTE/g for DPPH and ABTS respectively). Catechin, epicatechin, gallic acid, p-OH-Benzoic acid, rosmarinic acid, and epigallocatechin gallate, found in significant abundance in the extracts were assessed using molecular modelling with the aim to study their docking properties on a set of six enzymes used in this study. The extracts were moderately effective with MIC values ranging between 1.56 to 6.25mg/ml, but potent growth inhibitors of MRSA strains. Results amassed herein can be used as a stimulus for further studies geared towards the development of novel phyto-pharmaceuticals.

In vitro and in silico perspectives on biological and phytochemical profile of three halophyte species—A source of innovative phytopharmaceuticals from nature

BACKGROUND Halophytes are considered as valuable sources of traditional drugs in different countries. PURPOSE The present study aimed to evaluate biological and chemical fingerprints of three halophytes (Arthrocnemum macrostachyum (Moric.) C, Koch, Halimione portulacoides (L.) Aellen and Salicornia europaea L.). MATERIALS AND METHODS The antioxidant and enzymatic inhibitory potential (acetylcholinesterase, butyrylcholinesterase, α-amylase, α-glucosidase, and tyrosinase) were assessed. The total phenolic, flavonoid contents, and the chemical profiles were appraised using the ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry. Molecular docking was conducted to provide additional insights of molecular interactions of the enzymes/phytochemicals. RESULTS Ethyl acetate extract was the most efficient extract, with A. macrostachyum being the most potent towards DPPH and ABTS radicals and phosphomolybdenum assay. Ethyl acetate extract of A. macrostachyum was also the best reducing agent (CUPRAC and FRAP assays). Methanol and ethyl acetate extract of A. macrostachyum, H. portulacoides, and S. europaea showed significant enzyme inhibition potential. Ethyl acetate extract of A. macrostachyum showed the highest total phenolic (29.54 ± 0.78 mgGAEs/g extract) while the ethyl acetate extract of S. europaea was more abundant in flavonoids (18.26 ± 0.11 mgREs/g extract). Phytochemical profiling allowed the identification of several components in the methanolic extracts (16 in A. macrostachyum, 14 in H. portulacoides, and 11 in S. europaea), with quinic acid, p-coumaric acid, and rhamnetin being most abundant. Docking studies revealed that the above compounds showed scores for the enzymes tested. CONCLUSION The three halophytes studies could be considered as potential sources of biologically-active compounds for novel phytopharmaceuticals development.

Antimicrobial and Antibiotic Potentiating Activity of Essential Oils From Tropical Medicinal Herbs and Spices

Essential oils (EOs), which are complex blends of biologically active substances, are classified as natural products with pharmacological potential that can be of therapeutic benefit in the treatment and management of human diseases. EOs extracted from medicinal herbs and food plants are gaining a great deal of interest for their multifarious properties. The increased awareness in alternative natural substances is driving the research community to find new avenues for natural pharmacological agents. In this quest, EOs have been highlighted as natural substances having a rich source of compounds with antimicrobial and antibiotic potentiating properties. With the outbreak of antimicrobial resistance worldwide, EOs and their components have proved to provide useful template molecules for the development of alternative antimicrobial drugs. The purpose of this chapter is to provide an overview of the methods of extraction of EOs, their proficiency as antimicrobials, their mode of actions, and their efficacy in potentiating conventional antibiotics to counteract the action of resistant pathogens.