TY - JOUR
T1 - Antimicrobial and antioxidant activities of neem assisted silver-modified zeolite X synthesized from kaolin
AU - Kwakye, Ralph
AU - Boakye, Grace
AU - Vigbedor, Bright Yaw
AU - Aniagyei, Albert
AU - Asimeng, Bernard Owusu
AU - Antwi, Boniface Yeboah
AU - Neglo, David
AU - Nanga, Salifu
N1 - Publisher Copyright:
© 2026 Kwakye 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.
PY - 2026/2
Y1 - 2026/2
N2 - Zeolite X was synthesized from kaolin and then modified using (Azadirachta indica) neem together with silver nitrate solution by ion exchange. X-ray diffraction confirmed a highly crystalline FAU framework characterised by a low angle reflection, which showed that silver incorporation did not alter the zeolite structure. Scanning Electron Microscopy (SEM) revealed a well-defined polyhedral crystal for zeolite X, whiles the Ag-zeolite X exhibited increased surface heterogeneity and agglomeration. Fourier Transform Infrared (FT-IR) and Raman Spectroscopy further confirmed framework retention, with band broadening attributed to the partial substitution of Na+ by Ag+ within the zeolite lattice. The antimicrobial activity of zeolite X, Ag-zeolite X, were evaluated against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalis, Candida albicans, Aspergillus niger strains by Minimum Inhibition Concentration (MIC) and Minimum Bacterial/fungal Concentration (MBC/MFC) Assays. The antioxidant properties were evaluated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-Azino-bis (3-ethylbenzothialine-6-sulfonic acid (ABTS) radical scavenging assays. The unmodified zeolite X showed weak activity (MIC, MBC, MFC > 1 mg/mL, R > 4) whilst the Ag-zeolite X showed strong antimicrobial activity (MIC = 0.5–1.0 mg/mL, MBC, MFC = 0.5–2 mg/mL, R ≤ 4) across all tested strains. Antioxidant activity assessed using DPPH and ABTS radical scavenging assays showed significantly enhanced antioxidant performance for Ag-zeolite X compared to unmodified zeolite X, particularly in the ABTS assay. These findings demonstrate that neem-assisted silver modification enhances the bioactivity of kaolin-derived zeolite X while preserving its crystalline framework, supporting its potential application in biomedical, food packaging, and water treatment systems.
AB - Zeolite X was synthesized from kaolin and then modified using (Azadirachta indica) neem together with silver nitrate solution by ion exchange. X-ray diffraction confirmed a highly crystalline FAU framework characterised by a low angle reflection, which showed that silver incorporation did not alter the zeolite structure. Scanning Electron Microscopy (SEM) revealed a well-defined polyhedral crystal for zeolite X, whiles the Ag-zeolite X exhibited increased surface heterogeneity and agglomeration. Fourier Transform Infrared (FT-IR) and Raman Spectroscopy further confirmed framework retention, with band broadening attributed to the partial substitution of Na+ by Ag+ within the zeolite lattice. The antimicrobial activity of zeolite X, Ag-zeolite X, were evaluated against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Enterococcus faecalis, Candida albicans, Aspergillus niger strains by Minimum Inhibition Concentration (MIC) and Minimum Bacterial/fungal Concentration (MBC/MFC) Assays. The antioxidant properties were evaluated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-Azino-bis (3-ethylbenzothialine-6-sulfonic acid (ABTS) radical scavenging assays. The unmodified zeolite X showed weak activity (MIC, MBC, MFC > 1 mg/mL, R > 4) whilst the Ag-zeolite X showed strong antimicrobial activity (MIC = 0.5–1.0 mg/mL, MBC, MFC = 0.5–2 mg/mL, R ≤ 4) across all tested strains. Antioxidant activity assessed using DPPH and ABTS radical scavenging assays showed significantly enhanced antioxidant performance for Ag-zeolite X compared to unmodified zeolite X, particularly in the ABTS assay. These findings demonstrate that neem-assisted silver modification enhances the bioactivity of kaolin-derived zeolite X while preserving its crystalline framework, supporting its potential application in biomedical, food packaging, and water treatment systems.
UR - https://www.scopus.com/pages/publications/105030069116
U2 - 10.1371/journal.pone.0343110
DO - 10.1371/journal.pone.0343110
M3 - Article
AN - SCOPUS:105030069116
SN - 1932-6203
VL - 21
JO - PLoS ONE
JF - PLoS ONE
IS - 2 February
M1 - e0343110
ER -