Abstract
The objective of this study was to assess the anti-inflammatory effects of a chitosan (CHT) film loaded with an Arnebia euchroma extract, both in vitro and in vivo. Arnebia euchroma contains shikonin (SHKN), a naphthoquinone that exhibits notable anti-inflammatory, antimicrobial, and wound-healing properties. A high-quality SHKN extract was standardised and incorporated into CHT films, which were then evaluated in terms of their stability, drug release, antibacterial effectiveness and anti-inflammatory activity. Two concentrations of SHKN were employed the preparation of CHT films. In vitro studies showed that the optimal CHT film formulation remained stable for a period of four weeks at 4°C. A biphasic SHKN release profile was observed from the films, indicative of a sustained drug release mechanism. The films exhibited a strong antibacterial effect against Staphylococcus aureus (S. aureus) due to the presence of SHKN, but no such effect against Escherichia coli (E. coli). Furthermore, a synergistic antibacterial effect was noted when CHT was combined with A. euchroma extract against S. aureus. In vivo, the CHT film with A. euchroma extract demonstrated anti-inflammatory effects in a mice paw swelling test, comparable to betamethasone. The mice were divided into four groups of six, and the difference was not statistically significant (p-value>0.05). Histological examination substantiated the reduction of immune cell infiltration in the treatment group. The study concluded that CHT films containing A. euchroma extract exhibit promising anti-inflammatory and antimicrobial properties. Furthermore, they are suitable for use as wound dressings, offering high portability, mechanical strength, and non-adhesive properties, which makes them suitable for use in a variety of medical and pharmaceutical applications, as well as potential carriers for antimicrobial agents and antioxidants in various industries. In conclusion, the utilisation of chitosan films embedded with Arnebia euchroma extract may provide an accessible and convenient therapeutic application for a range of wounds and inflammatory conditions.