Probiotic-infused activated charcoal/hydroxyapatite microbeads: A novel strategy to disinfection
Abstract
Objectives. To develop a non-toxic Probiotic-Infused Microbead Disinfectant (PIMD) using activated charcoal and hydroxyapatite, designed to establish a long-term probiotic biofilm on high-risk surfaces (e.g., medical sink basins and food cutting boards) to combat pathogens, including antibiotic-resistant strains, through a dual mechanism: rapid microbial inhibition and sustained competitive exclusion.
Methods. An applied study was conducted in the Al-Baha region of Saudi Arabia (January 2021–May 2025) employing probiotic-based biotechnology to engineer spatially segregated microenvironments using activated charcoal–hydroxyapatite microbeads. The study integrated ecological modeling concepts—including Gause's competitive exclusion principle, Lotka–Volterra dynamics and agent-based cross-feeding simulations—with antimicrobial sensitivity assays and surface disinfection trials. Twelve probiotic strains capable of competitively excluding pathogens and producing antimicrobial compounds were encapsulated within activated charcoal and hydroxyapatite porous microbeads. The efficacy of the novel disinfectant was evaluated on stainless steel sink basins, food-grade cutting boards, and culture plates challenged with 43 pathogenic strains.
Results. PIMD demonstrated a shelf-life of ≥ 6 months at 4°C, rapid broad-spectrum disinfection efficacy (eliminating ≥ 99.9% of pathogens within ≤ 1 hours), and sustained protective biofilm-mediated efficacy for ≥ 21 days post-application. The mean inhibition zone diameter in the antimicrobial sensitivity tests was 13.84 ± 1.23 mm (n = 43 pathogens). Conclusion. PIMD represents a dual-action strategy combining rapid disinfection with sustainable microbial balance, for reducing reliance on antibiotics and chemical disinfectants while enhancing surface safety in diverse environments such as healthcare, food facilities, and beyond.