Characterization of Nigella sativa Oil–Camphor Formulation and Evaluation of Its Enhanced Anti-Inflammatory and Antimicrobial Activities

Characterization of Nigella sativa Oil–Camphor Formulation

Abstract

Camphor is a volatile monoterpenoid that is well known for its antimicrobial and anti-inflammatory properties, whereas Nigella sativa oil is a natural oil that exhibits a variety of bioactive phytochemicals. In this study, a formulation of Nigella sativa oil and camphor was prepared, and its physicochemical, chemical, thermal, and biological properties were evaluated with respect to the corresponding parts. The oil quality of Nigella sativa was found to be satisfactory, as indicated by its fat content of 40.21%, ash content of 6.74%, peroxide value of 3.995 ± 0.05 mEq/kg, free fatty acid value of 0.647 ± 0.001, iodine value of 124, and saponification value of 189.37. Numerous substantial bioactive compounds, such as camphor (8.78 min), p-cymene (4.12 min), thymoquinone (10.78 min), carvacrol (12.36 min), and longifolene (15.32 min), were identified by GC–MS profiling. The appropriate incorporation of camphor into the oil phase was demonstrated by determining the chemical composition of both the oil and the camphor in the resulting formulation. Characteristic absorption bands associated with C–H stretching at about 2922 and 2853 cm⁻¹, C=O stretching around 1744 cm⁻¹, C=C stretching near 1655 cm⁻¹, and C–O stretching within the 1238–1162 cm⁻¹ range were identified by FTIR analysis. These spectral features suggested there was relatively low chemical interaction and indicated that the individual elements were generally physically incorporated. A couple of contrasting stages of deterioration were observed by thermal analysis via TGA: camphor volatilization commenced between 80 and 180°C, and the oil matrix decomposed between 250 and 450°C. Moreover, the biological activity of the combined formulation was higher than that of each component. In addition to higher antibacterial inhibition zones, DPPH radical-scavenging activity reached 94.73 ± 1.24% at 1000 ppm, and anti-inflammatory activity was approximately 90.12% at 50 µL. Overall, the findings support the formulation potential as an organic bioactive preparation for further investigation by demonstrating that the addition of camphor could improve a variety of chemical and biological attributes of Nigella sativa oil.