Obaydah Alabrahim

Egypt

β-Cyclodextrin Nanoparticles Loaded with Boswellia Extract for Enhanced Antimicrobial and Antibiofilm Activity

Obaydah Abd Alkader Alabrahim¹, Mostafa Fytory¹,², Ahmed M. Abou-Shanab³, Jude Lababidi¹, Wolfgang Fritzsche⁴, Nagwa El-Badri³*, Hassan Mohamed El-Said Azzazy¹,⁴*

1. Department of Chemistry, School of Sciences & Engineering, The American University in Cairo, AUC Avenue, P.O. Box 74, New Cairo 11835, Egypt
2. Material Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, 62511, Beni-Suef, Egypt
3. Center of Excellence for Stem Cells and Regenerative Medicine, Zewail City of Science and Technology, Giza, 12578, Egypt
4. Department of Nanobiophotonics, Leibniz Institute of Photonic Technology, Jena 07745, Germany

Abstract

Background

Biofilm-associated infections remain a major challenge in healthcare due to their high tolerance to antibiotics and persistence in chronic and acute settings. Natural extracts with antimicrobial potential offer promising alternatives, yet they often suffer from poor stability, solubility, and limited efficacy. β-Cyclodextrin (βCD), an FDA-approved cyclic oligosaccharide, provides a biocompatible carrier for improving the delivery of hydrophobic bioactives. This study investigates a βCD inclusion complex encapsulating Boswellia sacra essential oil (BOS) as a multifunctional antimicrobial and antibiofilm nanotherapeutic.

Methods

The BOS–βCD inclusion complex was prepared using a co-precipitation method and fully characterized for physicochemical properties, morphology, and encapsulation efficiency. Antimicrobial activity was evaluated against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas putida using broth microdilution assays. Antibiofilm activity was assessed by quantifying biofilm prevention and disruption through crystal violet staining. Biocompatibility and oxidative stress induction were examined in human skin fibroblasts.

Results

Encapsulation of BOS into βCD significantly enhanced its antimicrobial potency, yielding a 4-fold improvement against Gram-positive bacteria and an 8-fold improvement against Gram-negative strains, with MIC values ranging from 2.5 to 5 mg/mL. The BOS–βCD complex demonstrated a dual antibiofilm mechanism: (1) inhibition of biofilm formation and (2) disruption of pre-established biofilms. Biofilm biomass was reduced by up to 93.78% (prevention) and 82.17% (disruption). Importantly, the formulation exhibited excellent cytocompatibility with no detectable oxidative stress induction in fibroblasts, supporting its safety for potential biomedical use.

Conclusions

The βCD-based inclusion complex effectively enhances the delivery and antimicrobial performance of Boswellia sacra essential oil while maintaining high biocompatibility. Its robust, dual-action antibiofilm activity positions this nanocomplex as a promising candidate for preventing and treating biofilm-associated infections and for further development in topical or biomedical applications.