Campylobacter jejuni related gastrointestinal infections are challenging to overcome due to emerging antimicrobial resistance that poses global public health concerns. The development of biopolymeric nanosystems encapsulating natural antimicrobials serves as an alternative-medicine based on phytoceuticals. Thymol, an essential ingredient extracted from the thyme plant (Thymus vulgaris), and oregano plant (Origanum vulgare) exhibits a wide range of applications including anti-inflammatory, antibacterial, and antioxidant properties. However, its bioavailability, low stability, and poor water solubility severely limit its applications. Herein, zein nanosystems encapsulating thymol (TH-ZNs) were successfully fabricated to enhance the antibacterial and antibiofilm potential of thymol against foodborne multidrug-resistant C. jejuni. Through the antisolvent precipitation technique, physically stable nanosystems were obtained exhibiting a high encapsulation efficiency of 87 ± 0.5 %. Scanning electron microscopy revealed slightly rough surface morphology of TH-ZNs. FTIR spectroscopy elucidated hydrophobic interactions between thymol and zein which facilitates the successful encapsulation of thymol. Dynamic light scattering (DLS) studies revealed that the entrapment of thymol in ZNs increased the size from 202 ± 1.4 nm to 212 ± 1 nm, whereas zeta potential values were reduced from −42 ± 3 mV to −37 ± 2 mV in the case of void and TH-ZNs, respectively. Furthermore, TH-ZNs exhibited higher antimicrobial and antibiofilm efficacy against C. jejuni as compared to free thymol for a longer period. These results indicate that TH-ZNs inhibited bacterial growth while being non-cytotoxic, thus improving the overall efficiency of phytoceuticals to develop alternative nanotherapeutics to combat the resistant zoonotic pathogen.
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