PHYSICOCHEMICAL PROPERTIES AND BIOLOGICAL ACTIVITIES OF OLIVE MILL WASTEWATER

Abstract

Olive Mill Wastewater (OMWW) is a significant environmental challenge due to its high organic matter content, particularly 1phenolic compounds, which can inhibit microorganism growth and cause pollution in surface water, soil, and ecosystems. Despite its pollution, OMWW is also a rich source of natural antioxidants, including polyphenols, which have various potential health benefits. This study focuses on the in vitro evaluation of the antibacterial and antioxidant activity of OMWW collected from traditional oil mills in Fez, Morocco, and Tizi Ouzou, Algeria. Physicochemical characterization revealed variations in pH, electrical conductivity, dry matter content, water content, ash content, organic materials, fat, suspended matter, polyphenols, and flavonoids between the two sources. Moroccan OMWW exhibited higher polyphenol content, known for its antioxidant properties. Bacteriological analyses indicated the absence of total aerobic mesophilic flora, total and fecal coliform, and Staphylococcus aureus in the studied OMWW, suggesting its potential antimicrobial properties attributed to its acidity and the presence of antimicrobial substances such as phenolic compounds. Moroccan and Algerian OMWW exhibited antibacterial effects against various bacterial strains, with minimum inhibitory concentrations (MIC) ranging from 3% to 14%.  The antioxidant activity of OMWW was evaluated using 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) tests, with Moroccan OMWW demonstrating slightly stronger antiradical and reducing power activities. This research highlights the promising potential of OMWW as a natural antimicrobial and antioxidant agent, potentially serving as a valuable source of bioactive compounds with potential therapeutic applications.

Keywords: Olive mill wastewater, Antioxidant activity, Antibacterial activity, Polyphenols.