Camphor

The fragrant camphor tree (Cinnamomum camphora) and its products, such as camphor oil, have been coveted since ancient times. Having a rich history of traditional use, it was particularly used as a fumigant during the era of the Black Death and considered as a valuable ingredient in both perfume and embalming fluid. Camphor has been widely used as a fragrance in cosmetics, as a food flavourant, as a common ingredient in household cleaners, as well as in topically applied analgesics and rubefacients for the treatment of minor muscle aches and pains. Camphor, traditionally obtained through the distillation of the wood of the camphor tree, is a major essential oil component of many aromatic plant species, as it is biosynthetically synthesised; it can also be chemically synthesised using mainly turpentine as a starting material. Camphor exhibits a number of biological properties such as insecticidal, antimicrobial, antiviral, anticoccidial, anti-nociceptive, anticancer and antitussive activities, in addition to its use as a skin penetration enhancer. However, camphor is a very toxic substance and numerous cases of camphor poisoning have been documented. This review briefly summarises the uses and synthesis of camphor and discusses the biological properties and toxicity of this valuable molecule.

Synergistic interactions between constituents of essential oils have been reported for several areas of research. In the present study, mechanisms that could explain the synergistic action of the two major insecticidal constituents of rosemary oil, 1,8-cineole and camphor against the cabbage looper, Trichoplusia ni were investigated. 1,8-Cineole was more toxic than camphor when applied topically to larvae, and when coadministered in their ratio naturally occurring in rosemary oil, the binary mixture was synergistic. However, when injected directly into larvae, camphor was more toxic than 1,8-cineole. GC-MS analyses showed that penetration of topically-applied camphor was significantly enhanced when it was mixed with 1,8-cineole in the natural ratio. A bioassay combining injection and topical application methods confirmed the increased penetration of both compounds when mixed, showing the same bioactivity as seen for higher amounts applied individually. Lowered surface tension as well as increased solubility of camphor by 1,8-cineole, along with the interaction between 1,8-cineole and the lipid layer of the insect's cuticle may explain the enhanced penetration of camphor. Because of the similarities in biological function of animal and microbial membranes, our finding has potential for application in other fields of study.

Candidaalbicans represents one of the most common fungal pathogens. Due to its increasing incidence and the poor efficacy of available antifungals, finding novel antifungal molecules is of great importance. Camphor and eucalyptol are bioactive terpenoid plant constituents and their antifungal properties have been explored previously. In this study, we examined their ability to inhibit the growth of different Candida species in suspension and biofilm, to block hyphal transition along with their impact on genes encoding for efflux pumps (CDR1 and CDR2), ergosterol biosynthesis (ERG11), and cytotoxicity to primary liver cells. Camphor showed excellent antifungal activity with a minimal inhibitory concentration of 0.125-0.35 mg/mL while eucalyptol was active in the range of 2-23 mg/mL. The results showed camphor's potential to reduce fungal virulence traits, that is, biofilm establishment and hyphae formation. On the other hand, camphor and eucalyptol treatments upregulated CDR1;CDR2 was positively regulated after eucalyptol application while camphor downregulated it. Neither had an impact on ERG11 expression. The beneficial antifungal activities of camphor were achieved with an amount that was non-toxic to porcine liver cells, making it a promising antifungal compound for future development. The antifungal concentration of eucalyptol caused cytotoxic effects and increased expression of efflux pump genes, which suggests that it is an unsuitable antifungal candidate.

Natural products have long been integral to traditional medicine, offering diverse therapeutic benefits. Increasing concerns about the side effects of synthetic drugs have heightened interest in plant-derived compounds. The camphor tree (Cinnamomum camphora (L.) J. Presl) and its derivatives, such as camphor oil, have been valued for centuries. Historically, C. camphora was used as a fumigant during the Black Death, a prized ingredient in perfumes, and a key component in embalming fluids. Today, camphor extracted from C. camphora is widely used as a fragrance in cosmetics, a flavoring agent in food, an ingredient in household cleaners, and a topical remedy for minor muscle pain. Camphor is primarily obtained through steam distillation of the wood but can also be synthetically produced from turpentine. Camphor exhibits a broad spectrum of biological activities, including insecticidal, antimicrobial, antiviral, anticoccidial, antinociceptive, anticancer, and antitussive effects, and has historically been employed to alleviate inflammation, congestion, pain, and irritation. This review integrates recently published research (up to 2025) on the biological activities and therapeutic applications of camphor that were not comprehensively addressed in earlier reviews. Furthermore, a mechanistic perspective is provided on camphor's pharmacological effects, including its antibacterial, antimicrobial, antiviral, and anticancer actions, highlighting the chemical basis underlying these activities. This review provides a comprehensive overview of the history, applications, and biological properties of camphor, emphasizing its potential in preventing and treating serious diseases such as cancer and diabetes. In addition, sustainability and translational relevance are emphasized, demonstrating how camphor exemplifies the integration of traditional knowledge with contemporary medicinal research. Overall, this review offers new insights into the therapeutic potential of camphor, underscoring its promising role in addressing major medical challenges while supporting the growing importance of plant-based compounds in modern healthcare due to their effectiveness, safety, and sustainability.