Chitosan nanocarriers loaded with Egyptian Calligonum comosum L'Hér. Extract: an eco-friendly approach for investigating triple-action biological activities.

Background: Calligonum comosum L'Hér. is a large perennial shrub that grows in the desert. This plant inhabits much of the Egyptian desert, but has not yet been scientifically validated. Herein, we demonstrate the antimicrobial, anti-inflammatory, antioxidant, and anticancer properties of the ethanolic extract of the Egyptian C. comosum (CE) and its novel eco-friendly chitosan nano-formula (CE/CsNPs), which is prepared using citrate as a crosslinker.

Methods: The produced plant ethanolic extract (CE) was chemically analyzed. The eco-friendly CE/CsNPs were successfully developed through the conjugation of CE with different concentrations (200, 350, and 400 mg/100 mL) within the chitosan nanoparticle; then, it was fully characterized for the determination of the optimum formula and followed by the assessment of the antioxidant effects, proinflammatory cytokines, evaluation of cytotoxicity against different types of cancer cell lines, and estimation of antimicrobial effects of CE and CE/CsNPs.

Results: The eco-friendly CE/CsNPs-2 encapsulating 350 mg of CE was selected for the in vitro studies, as it displayed NPs with a small size and a surface charge of 37.7 ± 1.91 mV with the best encapsulation efficiency (70.15 ± 1.58%) within the CsNPs, and it showed a good release profile. Transmission electron microscope (TEM) images confirmed the discrete spherical shape of CE/CsNPs-2, with no aggregations, and revealed a size range of 49.69 to 71.93 nm. FTIR displayed the successful incorporation of CE into the eco-friendly CsNPs. Regarding their biological activity, CE/CsNPs have superior efficacy with high cytotoxicity against cancer cell lines and antioxidant effects. RT-qPCR gene expression assessments displayed that CE/CsNPs resulted in a remarkable downregulation of the inflammatory cytokines' mRNA transcript levels (p < 0.05). It enhanced the antimicrobial effect, with an inhibition zone of 12.34 ± 0.75 mm for Escherichia coli, 16.41 ± 1.01 mm for Staphylococcus aureus, and 18.74 ± 1.13 mm for Candida albicans.

Conclusions: The CE possesses various biological activities, and the developed CE/CsNPs could serve as an appealing formulation to be further investigated for use in anticancer regimens.