What are Cloves?
Cloves are dried flower buds from a plant scientifically called Syzygium aromaticum. These are flower buds of the clove tree, an evergreen that belongs to the Myrtaceae family.
Clove buds are small, reddish-brown in color, and have a distinctively strong aroma and pungent taste.
The clove tree is native to the Maluku Islands in Indonesia but is also cultivated in other tropical regions, including Madagascar, Sri Lanka, and India. It thrives in warm, humid climates and well-drained soil.
Cloves have been used for centuries in several traditional medicines, including Ayurveda and Traditional Chinese Medicine. They have also been used in Indonesian, Thai and Kampo medicine of Japan for centuries.
This means that cloves have been clinically used as a medicine on billions of people for thousands of years.
Cloves have been used for numerous types of infections, including those caused by bacteria, viruses and fungi. They also have a way of deadening pain, which is why they are often used for relieving teeth infections. Traditional therapies have used cloves for gastrointestinal disorders, disorders of the kidneys and spleen, and for pain.
But because cancers are more of a modern disease, the use of medicinal herbs such as cloves has been overlooked as anticancer agents. Nonetheless, over a third of today’s anticancer agents are in fact based upon plant-derived pharmaceuticals.
As it turns out, cloves are not simply antibacterial, antifungal, antiviral and carminative: Cloves are also potent anticancer agents.
Primary Compounds of Cloves
Cloves contain several bioactive compounds, including:
Eugenol: The primary compound responsible for cloves' characteristic aroma and many of its health benefits, such as its antimicrobial and analgesic properties.
Acetyleugenol: Another phenolic compound with similar properties to eugenol.
Caryophyllene: A terpene with anti-inflammatory effects.
Gallic Acid: A phenolic acid with antioxidant properties.
Flavonoids: Including kaempferol and quercetin, which also contribute to cloves' antioxidant effects.
Traditional Medicine Uses
Ayurveda: Cloves, known as "Lavang" in Sanskrit, are used in Ayurvedic medicine to improve digestion, alleviate pain, and treat respiratory conditions.
Traditional Chinese Medicine (TCM): Cloves, referred to as "Ding Xiang," are used to warm the digestive system, dispel cold, and alleviate pain.
Middle Eastern and African Medicine: Cloves are used to treat various ailments, including digestive issues, respiratory infections, and oral health problems.
Health Benefits from the Research
1. Antimicrobial Properties: Cloves have potent antimicrobial properties, making them effective against bacteria, viruses, fungi, and parasites.
Research has found that cloves inhibit Plasmodium, Babesia, Theileria parasites, Herpes simplex, and hepatitis C viruses among others. Parasites inhibited include Giardia lamblia, Fasciolagigantica, Haemonchuscontortus, and Schistosomamansoni.
Cloves also make for good insecticides according to the research.
2. Anti-inflammatory Effects: Compounds like eugenol and caryophyllene possess anti-inflammatory properties, which can help alleviate inflammation-related conditions.
Cloves have also been shown in studies to improve wound healing.
Because cloves inhibit COX-2 enzymes they slow the inflammatory and pain processes.
3. Pain Relief: Cloves are traditionally used for their analgesic properties and can be applied topically or consumed to relieve toothaches, headaches, and muscle pain.
One clinical study compared the analgesic effects of eugenol and clove oil with benzocaine in dental procedures and found clove oil significantly reduced dental pain.
Other studies have shown that cloves help relief headache pain, joint pain and others.
4. Digestive Health: Cloves aid digestion by stimulating the production of digestive enzymes and reducing gas and bloating. Laboratory studies have shown cloves help balance gut probiotics and stimulates the production of enzymes for digestion.
5. Oral Health: Cloves have been used for centuries in oral care products due to their antimicrobial properties and ability to freshen breath.
6. Antioxidant Benefits: The phenolic compounds and flavonoids in cloves scavenge free radicals, protecting cells from oxidative damage and reducing the risk of chronic diseases. Compounds such as eugenol, eugenyl acetate, caryophyllene, and humulene in cloves have been shown to help protect our bodies from oxidation.
Cloves inhibit cancer in laboratory research
This has been confirmed by research by scientists from the University of Minnesota, the University of Pittsburg and China’s Capital Medical University in a series of experiments.
The researchers tested a variety of human cancer cells in the laboratory using different whole clove extracts. The researchers tested SKOV-3 human ovarian cancer cells, human HeLa cervical epithelial cells, BEL-7402 human liver cancer cells, HT-29 human colon cancer cells, MCF-7 human breast cancer cells and PANC-1 human pancreatic cancer cells. They also tested normal colon wall cells and normal lung cells as controls.
The acronym names of the cancer cells above relate to a specific human cancer taken from a specific cancer sufferer. In other words, these are live human cancer cells that have been allowed to grow within the laboratory.
The researchers found that the clove extract halted the activity and growth of the colon cancer cells, the breast cancer cells, the ovarian cancer cells, the liver cancer and the colon cancer cells.
Meanwhile, the clove extract was not dangerous to the normal cells.
This of course means that the cloves were smart. They stopped the growth of the cancer cells while allowing regular cells to grow.
Not only that, but they halted the cancer cells in a dose-dependent manner. This means that the more clove was applied, the greater the anticancer effect. This is considered the gold-standard of determining whether a particular compound is causing the effect.
Extracting the anticancer compounds
The extract that proved the most efficacious was an ethanol extract. This means basically that the cloves were soaked in alcohol and the resulting solution was used (don’t self-medicate – talk to your doctor). More specifically, the cloves were soaked in 95% alcohol for 72 hours at room temperature. The whole extract was then concentrated.
The extracting process had the effect of releasing the medicinal compounds from cloves that may or may not be released when they are eaten. This is a common method used by herbalists for centuries. Today these are called tinctures.
Cloves have many different medicinal compounds. Some have been isolated while others have not. Those that have been isolated and identified include eugenol, β-caryophyllene, humulene, chavicol, methyl salicylate, α-ylangene, eugenone, eugenin, rhamnetin, kaempferol, eugenitin, oleanolic acid, stigmasterol, campesterol and others.
The variety of these compounds have been categorized as sesquiterpenes, flavonoids, triterpenoids and others.
This whole array of compounds within natural herbs provides the basis for the safety of many medicinal herbs. When compounds are isolated and prescribed without nature’s blend of other constituents, the medicine often produces side effects. These other compounds provide a buffering effect.
That said, the two compounds that the researchers found provided critical anticancer potency were oleanolic acid and eugenol. The former is a triterpenic acid.
Oleanolic acid
This is not the first time that oleanolic acid has been found to be a potent anticancer agent. A 2013 study from the Chinese Academy of Sciences found that oleanolic acid was able to arrest and halt the cell cycle of human pancreatic cancer cells.
The researchers further found that oleanolic acid accomplished this using several different strategies, including interfering with the mitochondria of the cancer cells and altering the genes of the cancer cells.
Yes, this natural constituent of clove altered the cancer cells’ DNA. Other anticancer plants such as red raspberry, Euphorbia herb and rainforest herbs also modulate DNA as well.
REFERENCES:
Liu H, Schmitz JC, Wei J, Cao S, Beumer JH, Strychor S, Cheng L, Liu M, Wang C, Wu N, Zhao X, Zhang Y, Liao J, Chu E, Lin X. Clove extract inhibits tumor growth and promotes cell cycle arrest and apoptosis. Oncol Res. 2014;21(5):247-59. doi: 10.3727/096504014X13946388748910.
Wei J, Liu M, Liu H, Wang H, Wang F, Zhang Y, Han L, Lin X. Oleanolic acid arrests cell cycle and induces apoptosis via ROS-mediated mitochondrial depolarization and lysosomal membrane permeabilization in human pancreatic cancer cells. J Appl Toxicol. 2013 Aug;33(8):756-65. doi: 10.1002/jat.2725.
Haro-González JN, Castillo-Herrera GA, Martínez-Velázquez M, Espinosa-Andrews H. Clove Essential Oil (Syzygium aromaticum L. Myrtaceae): Extraction, Chemical Composition, Food Applications, and Essential Bioactivity for Human Health. Molecules. 2021 Oct 22;26(21):6387. doi: 10.3390/molecules26216387.
Batiha GE, Alkazmi LM, Wasef LG, Beshbishy AM, Nadwa EH, Rashwan EK. Syzygium aromaticum L. (Myrtaceae): Traditional Uses, Bioactive Chemical Constituents, Pharmacological and Toxicological Activities. Biomolecules. 2020 Jan 30;10(2):202. doi: 10.3390/biom10020202.
Marchese A, Barbieri R, Coppo E, Orhan IE, Daglia M, Nabavi SF, Izadi M, Abdollahi M, Nabavi SM, Ajami M. Antimicrobial activity of eugenol and essential oils containing eugenol: A mechanistic viewpoint. Crit Rev Microbiol. 2017 Nov;43(6):668-689. doi: 10.1080/1040841X.2017.1295225.
Chaieb K, Hajlaoui H, Zmantar T, Kahla-Nakbi AB, Rouabhia M, Mahdouani K, Bakhrouf A. The chemical composition and biological activity of clove essential oil, Eugenia caryophyllata (Syzigium aromaticum L. Myrtaceae): a short review. Phytother Res. 2007 Jun;21(6):501-6. doi: 10.1002/ptr.2124.
Zari AT, Zari TA, Hakeem KR. Anticancer Properties of Eugenol: A Review. Molecules. 2021 Dec 6;26(23):7407. doi: 10.3390/molecules26237407.
Maggini V, Semenzato G, Gallo E, Nunziata A, Fani R, Firenzuoli F. Antimicrobial Activity of Syzygium aromaticum Essential Oil in Human Health Treatment. Molecules. 2024 Feb 25;29(5):999. doi: 10.3390/molecules29050999.
Havale R, Rao DG, S P S, M Tuppadmath K, Tharay N, Mathew I, Taj KE. Comparative evaluation of pain perception following topical application of clove oil, betel leaf extract, lignocaine gel, and ice prior to intraoral injection in children aged 6-10 years: a randomized control study. J Dent Anesth Pain Med. 2021 Aug;21(4):329-336. doi: 10.17245/jdapm.2021.21.4.329.