Aurelie Dzenga Njeunkam¹, Luciane Marlyse Moungang¹*, Mireille Ebiane Nougang², Yves Yogne Poutoum¹, Jean Samuel Eheth³, Adams Ibn Rabiou Mouhama Sani¹ and Moïse Nola¹

¹Hydrobiology and Environment Laboratory, University of Yaounde I, Faculty of Sciences, P.O. Box 812, Yaounde, Cameroon ²Laboratory of Advanced and Applied Zoology, University of Maroua, Faculty of Sciences, P.O. Box 814, Maroua, Cameroon ³Microbiology Laboratory, University of Yaounde I, Faculty of Sciences, P.O. Box 812, Yaounde, Cameroon

*Corresponding Author: Luciane Marlyse Moungang, Hydrobiology and Environ- ment Laboratory, University of Yaounde I, Faculty of Sciences, P.O. Box 812, Yaounde, Cameroon.

Received: July 27, 2026; Published: October 21, 2026

Abstract

This study investigates the influence of growth phase on the adhesion of Enterococcus faecalis to non-activated charcoal in aquatic environments, a potential low-cost solution for microbial water decontamination. E. faecalis, a fecal indicator bacterium, was isolated from polluted water in Cameroon and cultured in peptone water to determine growth phases (exponential phase: 4 to10 hours, stationary phase: 10 to 34 hours). Adhesion experiments were conducted using charcoal fragments from Cylicodiscus gabunensis wood, sterilized and immersed in bacterial suspensions under varying pH (4, 7, 10), temperatures (7°C, 23°C, 37°C, 44°C), and organic matter concentrations (0, 500, 1000 mg/L). Results showed that adhesion was significantly higher in the exponential phase (118.12 ± 2.34 to 148.69 ± 2.01×105 CFU/cm²) compared to the stationary phase (5.2 ± 1.65 to 9.55 ± 2.14×105 CFU/cm²), attributed to increased cellular activity and exopolymer synthesis. Maximum adhesion occurred later in the exponential phase (12 to 24 hours) versus early in the stationary phase (3hours), reflecting differences in adhesion mechanisms: reversible electrostatic interactions dominated the stationary phase, while irreversible exopolymer-mediated binding prevailed in the exponential phase. The kruskal wallis « H » test reveals a highly significant difference (P < 0.01) in the adsorption of bacterial cells across the various growth phases considered. The Freundlich adsorption coefficient (Kf) ranged from 3.63 to 50463.22 cells/cm², with the highest values observed at pH 4 and 37°C. Adhesion rates reached 20.343 ± 2.15×105 CFU/cm²/h, suggesting a microbial load reduction of 10%, below WHO standards for standalone water treatment. The study highlights non-activated charcoal’s potential as a supplementary filtration material in multi-stage systems, though further optimization is needed to meet purification targets.

Keywords: Enterococcus faecalis; Bacterial Adhesion; Non-Activated Charcoal; Growth Phase; Water Decontamination

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Citation

Citation: Luciane Marlyse Moungang.,et al. “Role of the Enterococcus Faecalis Growth Phase in the Purification of Water by Non-Activated Charcoal". Acta Scientific Microbiology 9.11 (2026): 08-22.

Copyright

Copyright: © 2026 Luciane Marlyse Moungang.,et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.