Physicochemical characterisation of biochar derived from <i>sargassum</i> spp. and its antibacterial activity

This experiment aims to study the potential use of biochar derived from <i>Sargassum</i> spp. as an innovative ingredient in homemade soap, focusing on its antibacterial activity. The pyrolysis process was conducted at 700 °C with a heating rate of 10 °C min⁻¹ for 2 h under a nitrogen atmosphere with KOH chemical activation. The physicochemical properties of the biochar were investigated using XRD, FTIR, Raman, BET surface analysis, and SEM. Highly porous biochar was successfully synthesised, achieving a large specific surface area of 1600 m² g⁻¹ and a well-developed microporous structure distributed across the surface of the biochar. <i>Klebsiella pneumoniae, Staphylococcus aureus</i>, and <i>Salmonella choleraesuis</i> were used as model pathogens to evaluate the antibacterial activity of biochar-enriched homemade soap using Müeller-Hinton Agar and the Kirby-Bauer test. The antibacterial evaluations demonstrated that the incorporation of biochar into homemade soap partially inhibited the growth of these model pathogens bacteria.