Scientific name: Calendula officinalis L.

Family: Asteraceae

Part used: Flowers

Common names: Marigold, Pot Marigold, Mary-bud, Garden Marigold

Introduction:

The flower petals of Calendula officinalis have been used for their anti-inflammatory and skin healing benefits for centuries, which is why we use it in our award winning multi-tasking face and body oil here in Modern Botany.

Calendula is a well-known traditional medicinal herb that is native to central, eastern and southern Europe1.  It is thought to have originated in the Mediterranean, Egypt and Iran but is now widely cultivated all over Europe and in North America.  Calendula has been used since ancient times in Indian, Arabic, Egyptian, Roman and Greek cultures.  In India, wreaths of marigolds were used to crown the gods 2,3.

Calendula comes from the latin ‘calends’, because it was always in bloom on the first day of each month 2,3, .  Calendula is also known as the “herb of the sun”, because it’s flowers open in the morning and close in the evening.  In Greek mythology, calendula is said to be named after the wood nymphs who fell in love with Apollo 4.  The Old Saxon name for calendula is “ymbglidegold’ which means “it turns with the sun” and the common name marigold is likely to refer to the Virgin Mary 5.

Calendula was also traditionally used to colour cheese in England and “The Receipt Book of Charles Carter” (1732), gives a recipe for marigold wine 6.  It has also been used as a saffron substitute.  The flowers were also used to dye foods and cosmetics 5.

Calendula is an annual, ornamental, aromatic plant which can grow up to 0.6m high and flowers continuously from May until October.  The stem is erect and hairy. The leaves are light green and the flowers are bright yellow to orange.  The seed is a distinctive half-moon shape.   It can grow on many types of soil and is found along roadsides and on waste, cultivated and arable land.  It is bee-pollinated, attracts wildlife and is also a good companion plant as it attracts pests 3,7.

Traditional Medicinal Uses:

·       Calendula is a detoxifying and cleansing herb which has been used since the middle ages for its anti-inflammatory and skin healing benefits.  It has been used as an antifungal and antiseptic remedy for wounds, burns, freckles and for diaper rashes and other inflammatory conditions of the skin and mucous membranes 8.  Calendula has also been used as an antispasmodic, to eliminate parasites and for conjunctivitis 1,16 and it is said that the sap from the stem removes warts, corns and callouses 2.

Calendula was used by doctors in the American Civil War to treat open wounds 2,3,8.

Biological Properties:

Calendula flowers are anti-inflammatory (1), antioxidant, antiseptic, anti-fungal, anti-bacterial (2), anti-viral (3), immune stimulant and wound-healing.  They are also effective against oral inflammations, varicose veins, chilblains and skin conditions such as dermatitis (and diaper dermatitis) (4) and impetigo.  It has also shown to be effective against osteoarthritis (5).

(1)   Anti-inflammatory - A tincture of Calendula flowers was shown to have a pronounced anti-inflammatory action which was comparable with diclofenac in a 2016 study which looked at therapy for the prevention of Atherosclerosis 9.

(2)   Antibacterial – Calendula oil inhibited the growth of Bacillus subtillus, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albacans 10.

(3)   Anti-viral -  A tincture of calendula flowers suppressed Herpes simplex and Influenza viruses 11.

(4)   Dermatitis - In a 2005 study, cream with marigold extract showed a significant protective effect against contact dermatitis 12.  A clinical trial using calendula extract showed that it provided good protection against acute dermatitis on women undergoing postoperative radiation therapy for breast cancer 13. 

Constituents:

Calendula has high amounts of flavonoids which give it its antioxidant properties.  The flowers contain oleanolic acid saponins, triterpene alcohols including calenduladiol and faradiol, quercetin derivatives (flavonoids) and carotenoids 1,14.  The carotenoids are the source of Calendulas orange-yellow colour.  

 

          

Calenduladiol – C30H50O2 Faradiol – C30H50O2 Oleanolic acid – C30H48O3

Commercial uses:

Medicine:

Medicinal use for wound-healing and as an anti-inflammatory is governed by various European pharmacopoeias, the German Commission E, the European Scientific Co-operative on Phytotherapy and WHO monographs 8.

Calendula is used for skin inflammation, chapped lips and cracked nipples from breast-feeding 3. The oil is used in aromatherapy skin treatments.  Ointments are used for leg ulcers and varicose veins.  Oral infusions are used to aid in digestion and promote bile production and mouthwashes that contain marigold extract are used to promote gum healing after tooth extraction.

Cosmetics:

Calendula is used in many cosmetic products including skin creams, deodorants, suntan lotions, shaving creams, shampoos and baby products 14.

Calendula is allowed in cosmetic baby toiletries per the Council of Europe, 1989 as it has been shown to be effective in the topical treatment of nappy rash 15.

Food:                 

The petals can be scattered on salads to add colour or added to soups.  They are often used in lieu of saffron.  The leaves are edible but can be unpalatable or bitter 5.

Calendula has been listed as GRAS (Generally regarded as safe) by the US FDA 16.

Contaminants and adulterants:

Adulteration is rare1.  The main confusion is with different species within the same family. 

Calendula should not be confused with other marigolds such as Tagetes patula (French marigold), T. erecta (African marigold) and T. minuta (Incan marigold) which are commonly used in vegetable gardens to repel insects, but do not have the same biological properties 3.

Modern Research

In a 2011 study, Calendula was found to be a safe and effective treatment for nappy rash in infants 17.

Calendula was found to enhance collagen content in human skin cells in a study which looked at the wound-healing benefits of Calendula 18.

Contraindications:

Individuals with hypersensitivity to arnica or other members of the Asteraceae family should avoid use 16.

Summary / Conclusion

Calendula has been used for its healing effects for centuries without documented issues.   It has consistently been shown to provide gentle, non-invasive treatment and several studies have confirmed its healing and anti-inflammatory effects.   Clinical tests have supported its safety and lack of skin irritation 3,4,16.  It grow prolifically in Ireland so would be a perfect crop for future herb farming.

References:

(1) Bisset, N. (2001). Herbal drugs and phytopharmaceuticals. 1st ed. Stuttgart: Medpharm scientific publ.

(2) McVicar, Jekka (2011). Jekka's Complete Herb Book. 1st ed. London: Kyle Cathie. Print.

(3) Fetrow, Charles H., and Avila, Juan R. (2003). Professional's Handbook of Complementary & Alternative Medicines (3). Philadelphia, US: Wolters Kluwer Health.

(4) Basch, E et al. (2006). "Marigold (Calendula Officinalis.): An Evidence-Based Systematic review By The Natural Standard research Collaboration". Journal of Herbal Pharmacotherapy 6.3/4:135-59.

(5) Sharrif Moghaddasi Mohammad and Kashani, H. (2012). Pot marigold (Calendula officinalis) medicinal usage and cultivation. Scientific Research and Essays, 7(14)

(6) Rohde, E. (1922). A garden of herbs. 1st ed. London: P.L. Warner.

(7) World Health Organisation (WHO), (2004). WHO monographs on selected Medicinal Plants. Vol. 2. Geneva, Switzerland: World Health Organisation

(8) Arora D, Rani A, Sharma A. (2013). A review on phytochemistry and ethnopharmacological aspects of genus Calendula. Phcog Rev;7:179-87

(9) Kirichenko T, Sobenin I, Nikolic D, Rizzo M, Orekhov A. (2016). Anti-cytokine therapy for prevention of atherosclerosis. Phytomedicine. [Online]. 23(11), 1198-1210. 

(10) Janssen, A., Scheffer, J. and Svendsen, A. (1987). Antimicrobial Activity of Essential Oils: A 1976-1986 Literature Review. Aspects of the Test Methods. Planta Medica, 53(05), pp.395-398.

(11) Bogdanova NS, Nikolaeva IS, Shcherbakova LI, Tolstova TI, Moskalenko NIu, Pershin GN (1970). Study of antiviral properties of Calendula officinalis. Farmakol Toksikol. 1970. May-Jun;33(3):349-55.           

(12) Fuchs SM, Schliemann-Willers S, Fischer TW, Elsner P, (2005). Protective Effects of Different Marigold (Calendula Officinalis L.) and Rosemary Cream Preparations Against Sodium-Lauryl-Sulfate-Induced Irritant Contact Dermatitis. Skin Pharmacol Physiol 18 (4), 195-200.

(13) Pommier, P., Gomez, F., Sunyach, M., D'Hombres, A., Carrie, C. and Montbarbon, X. (2004). Phase III Randomized Trial of Calendula Officinalis Compared With Trolamine for the Prevention of Acute Dermatitis During Irradiation for Breast Cancer. Journal of Clinical Oncology, 22(8), pp.1447-1453.

(14) Khan, Ikhlas A., and Abourashed, Ehab A. (2011). Leung's Encyclopedia of Common Natural Ingredients: Used in Food, Drugs and Cosmetics (3). Hoboken, US: John Wiley & Sons, Incorporated.

(15) European Medicines Agency (EMA) (2008). Committee on Herbal Medicinal Products (HMPC). Assessment report on Calendula officinalis L., flos., London, UK. 

(16) Barnes, Joanne, Linda A Anderson, and J. David Phillipson. (2007). Herbal Medicines. 3rd ed. London [u.a.]: Pharmaceutical Press, 2007. Print

(17) Yunes Panahi, Mohamad Reza Sharif, Alireza Sharif, et al. (2012) “A Randomized Comparative Trial on the Therapeutic Efficacy of Topical Aloe vera and Calendula officinalis on Diaper Dermatitis in Children,” The Scientific World Journal, vol. 2012, Article ID 810234, 5 pages, 2012. doi:10.1100/2012/810234

(18) Nicolaus, C., Junghanns, S., Hartmann, A., Murillo, R., Ganzera, M. and Merfort, I. (2017). In vitro studies to evaluate the wound healing properties of Calendula officinalis extracts. Journal of Ethnopharmacology, 196, pp.94-103.