OTICYS – TECHNICAL DATA SHEET
Calendula officinalis (marigold) flower extract
Calendula officinalis (pot marigold) flower extracts have a long-lasting tradition in ethnopharmacology. Currently, the European Medicines Agency (EMA) has approved its lipophilic and aqueous alcoholic extracts as traditional medicinal products for the treatment of minor inflammation of the skin and as an aid in the healing of minor wounds1. The effect of three different extracts from Calendula flowers (n-hexanic, ethanolic, aqueous) on the inflammatory phase of wound healing was studied in human immortalized keratinocytes and human dermal fibroblasts. The effect of Calendula extracts on the new tissue formation phase of wound healing was evaluated by studying the migratory properties of these extracts, triterpene mixtures and single compounds in human immortalized keratinocytes using the scratch assay. Finally, the effect of the extracts on the formation of granulation tissue in wound healing was studied using bacterial collagenase isolated from Clostridium histolyticum and the determination of soluble collagen in the supernatant of human dermal fibroblasts2.
C. officinalis Linn. (Pot marigold) has been traditionally used for inflammations of the oral and pharyngeal mucosa, wounds and burns3. Calendula tea is used as eyewashes, gargles, diaper rashes and other inflammatory conditions of the skin and mucous membranes4.
In veterinary practice, Marigold was proven to have antibacterial and antifungal effects of a rather broad-spectrum including antibiotic-resistant bacteria. This makes it an interesting new option for the treatment of pyoderma, otitis externa, infected wounds and dermatophytosis. In the same research, it showed wound-healing properties and is thus promising candidates in line to fill the therapeutic gap in canine wound-healing agents5.
Origanum vulgare essential oil
The efficacy of oregano oil against pathogenic bacteria has been investigated in numerous studies. In one of them6, oregano oil showed a significant anti-bacterial activity against 11 MDR clinical isolates including four Acinetobacter baumannii, three Pseudomonas aeruginosa, and four methicillin-resistant Staphylococcus aureus (MRSA), with a MIC ranging from 0.08 mg/ml to 0.64 mg/ml. Oregano oil also effectively eradicated biofilms formed by each of the 13 pathogens above at similar MICs. In vivo study using the third-degree burn wounds infected with PA01 or USA300 demonstrated that oregano oil, topically applied 24 h after bacterial inoculation, sufficiently reduced the bacterial load in the wounds by 3 log10 in 1 h, as measured by drastic reduction of bacterial bioluminescence. This bactericidal activity of oregano oil concurred with no significant side effect on the skin histologically or genotoxicity after three topical applications of oregano oil at 10 mg/ml for three consecutive days. The investigation suggests potentials of oregano oil as an alternative to antibiotics for the treatment of wound-associated infections regardless of antibiotic susceptibility.
Origanum vulgare essential oil has also proven to be active against clinical isolates of oral candida, showing 30±3mm of zone of inhibition as against 19mm for fluconazole7. In another study8, in vitro activity of the essential oil extracted from Origanum vulgare was evaluated against sixteen Candida species isolates. Standard strains tested comprised C. albicans (ATCC strains 44858, 4053, 18804 and 3691), C. parapsilosis (ATCC 22019), C. krusei (ATCC 34135), C. lusitaniae (ATCC 34449) and C. dubliniensis (ATCC MY646). Six Candida albicans isolates from the vaginal mucous membrane of female dogs, one isolate from the cutaneous tegument of a dog and one isolate of a capuchin monkey were tested in parallel. All isolates tested in vitro were sensitive to O. vulgare essential oil. The chromatographic analysis revealed that the main compounds present in the essential oil were 4-terpineol (47.95%), carvacrol (9.42%), thymol (8.42%) and α-terpineol (7.57%). The antifungal activity of O. vulgare essential oil against Candida spp. observed in vitro suggests its administration may represent an alternative treatment for candidiasis.
Research conducted in 2003/2004 documented and validated (in a non-experimental way) ethnoveterinary medicines used by small-scale, organic livestock farmers in British Columbia (BC), Canada9. During this study, the essential oils of Origanum vulgare L., and Thymus vulgaris L. exhibited very strong free radical scavenging activity. The essential oil of T. vulgaris exhibited the highest OH radical scavenging activity, although it did not reach 50% of neutralization (IC (50)). The antimicrobial activity was tested against 13 bacterial strains and six fungi. The most effective antibacterial activity was expressed by the essential oil of oregano, even on multiresistant strains of Pseudomonas aeruginosa and Escherichia coli.
Oregano essential oil was tested along with other essential oils (EOs) which are recommended by some veterinarians to treat otitis externa in pets, against bacterial and fungal pathogens previously isolated from dogs and cats with otitis externa10. In particular, the analyses were carried out against Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus pseudointermedius, Aspergillus niger, Aspergillus fumigatus, Aspergillus terreus, Candida albicans, Candida tropicalis, Trichosporon sp., and Rhodotorula sp. O. vulgare showed superior antibacterial activity, even if not against all the strains. Also, most fungi were inhibited by O. vulgare.
- EMA, https://www.ema.europa.eu/en/medicines/herbal/calendulae–flos
- Nicolaus C, Junghanns S, Hartmann 2, Murillo R, Ganzera M, Merfort I. In vitro studies to evaluate the wound healing properties of Calendula officinalis extracts. J Ethnopharmacol. 2017 Jan 20; 196:94-103.
- Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs. Austin, TX, Boston: American Botanical Council, Integrative Medicine Communications; 2001. p. 376-8.
- Safdar W, Majeed H, Naveed I, Kayani WK, Ahmed H, Hussain S, et al.
Pharmacognostical study of the medicinal plant Calendula officinalis L. (family Compositae). Int J Cell Mol Biol 2010; 1:108-16.
- Tresch M, Mevissen M, Ayrle H, Melzig M, Roosje P, Walkenhorst M Medicinal plants as therapeutic options for topical treatment in canine dermatology? A systematic review. BMC Vet Res. 2019 May 27;15(1):174.
- Lu M, Dai T, Murray CK, Wu MX. Bactericidal Property of Oregano Oil Against Multidrug-Resistant Clinical Isolates. Front Microbiol. 2018 Oct 5;9:2329.
- Bhat V, Sharma SM, Shetty V, Shastry CS, Rao CV, Shenoy S, Saha S, Balaji S. Characterization of Herbal Antifungal Agent, Origanum vulgare against Oral Candida spp. Isolated from Patients with Candida-Associated Denture Stomatitis: An In vitro Study. Contemp Clin Dent. 2018 Jun;9(Suppl 1): S3-S10
- Cleff MB, Meinerz AR, Xavier M, Schuch LF, Schuch LF, Araújo Meireles MC, Alves Rodrigues MR, de Mello JR. In vitro activity of origanum vulgare essential oil against candida species. Braz J Microbiol. 2010 Jan;41(1):116-23.
- Lans C, Turner N, Khan T. Medicinal plant treatments for fleas and ear problems of cats and dogs in British Columbia, Canada. Parasitol Res. 2008 Sep;103(4):889-98.
- Ebani VV, Nardoni S, Bertelloni F, Najar B, Pistelli L, Mancianti F. Antibacterial and Antifungal Activity of Essential Oils against Pathogens Responsible for Otitis Externa in Dogs and Cats. Medicines (Basel). 2017 Apr 21;4(2).