Written by Dorene Petersen, Founding President of American College of Healthcare Sciences, ACHS.edu. Based on Dorene's article, Generous Ginger Essential Oil, first published in the International Herb Association Ginger Herb of the Year™ 2023. Reprinted with permission.
This wonderful oil is loaded with potent health-giving aroma molecules packing a powerful wellness punch. Ginger Oil Zingiber officinale Roscoe, is from the family Zingiberaceae and is known as common ginger, Jamaican ginger, or ginger root. The Zingiberaceae plant family is rich with powerful essential oils and includes turmeric Curcuma longa (L.) and cardamom Elettaria cardamomum (L.) Maton.
The Greeks and Romans were onto something, as they highly valued ginger root traded by Arabian merchants via the Red Sea. It was introduced to France and Germany in the 9th century and a century later to England. Spanish conquistadors were responsible for taking ginger to the West Indies and Mexico, and as early as 1547. Later, Jamaica exported ginger back to Spain.
Paracelsus (1493-1541), who popularized the "Signatura doctrinae," now known as the Doctrine of Signatures,1 identified similarities between the shape of ginger and the human digestive system. Paracelsus was indeed very perceptive, as modern research confirms ginger's support for the digestive system. In the 12th century, Saint Hildegard referred to ginger as having "aphrodisiac properties, especially for stimulating the vigor of older men married to younger women."
According to the Fragrance Raw Material Monographs, ginger essential oil has been in public use since before the 1900s.2 Ginger essential oil was approved in 1965 by the Food and Drug Administration (FDA) for food use and designated Generally Recognized as Safe (GRAS) status. Both ginger essential oil and the solvent-free ginger oleoresin, a naturally occurring combination of the oil and resin, are listed on the GRAS list.3 Ginger is still used extensively in Chinese medicine.
The Fragrance Raw Material Monographs also state that the Council of Europe in 1970 included ginger oil in the list of substances permissible for use with a possible limitation of the active principle zingiberene in the final product.4
As a rule, essential oils should always be purchased only after checking the specific Latin name. Ginger is no exception as it can be confused with galangal Alpinia officinarum (Hance), also from the Zingiberaceae family and called ginger root or Chinese ginger. While galangal has some traditional medicinal similarities, including being a Chinese Pharmacopoeia noted cure for stomach aches,5 the constituent profile of the essential oil is very different from Z. officinale.
Ginger is cultivated in tropical and subtropical countries, such as Jamaica, West Africa, China, Sierra Leone, India, Indonesia, Vietnam, and Australia. Ginger is easy to grow if you are lucky enough to live in a tropical or subtropical climate. It is an herbaceous perennial with a horizontal creeping rhizome and an annual stem that grows to a height of two to three feet. The flower is yellow with a purple lip. Propagate it from cuttings rather than seeds. Each rhizome has an eye that will readily shoot. A light, sandy loam with plenty of rain and sunshine is necessary for a good crop. It does best in a composted and mulched bed. The rhizomes mature nine to 10 months after planting. The oil is found mainly in the epidermal tissue of the rhizome. There are many commercial varieties of the root. The cultivar, geographical origin, maturity of the rhizome at harvest, agricultural and climatic conditions experienced during its growth cycle, the oil extraction process, and whether the rhizome is fresh or dried when distilled will all influence the composition of ginger oil and, subsequently, its aromatic profile. Jamaican ginger essential oil is the most sought-after for aromatherapy with a sweet peppery aromatic profile. Nigerian ginger essential oil is also considered to be a good option.
Ginger essential oil is usually produced from dried, whole rhizomes, fresh peelings, and shavings if used immediately. Fresh ginger is not traditionally used to make the oil; if used, however, the final essential oil composition will be different. The dried rhizomes must be chopped or coarsely ground to expose more of the secretory cell surface to steam. The distillation waters may require cohobation or running the water through the distillation process again to remove all the oil. The yield is usually around 3%. A solvent extraction is also made with ground ginger, which produces a ginger absolute. Oleoresin contains the nonvolatile pungent principles that make ginger so unique. Ginger absolute is also made using a carbon dioxide (CO2) extraction. Ginger CO2 is said to possess the most true-to-nature aroma of ginger. The solvent absolute, which may still contain residual solvents, is used more in perfumery. In contrast, the solvent-free CO2 extract or oleoresin is used more in flavoring and aromatherapy treatments.
| Ginger rhizome showing oil globule oozing from secretory cell. Image by Svoboda, K. & Svoboda, T. (2000). Secretory Structures of Aromatic and Medicinal Plants. Knighton, UK: Microscopix Publications. Reproduced with permission. |
Looking at the range of organoleptic and physical characteristics of an essential oil is a tried-and-true way to evaluate its quality. Organoleptic analysis reveals aspects using one or all of your senses. This means we look at the color, aroma, feel, and taste. The color is indicative to some extent of the geographical source. Ginger essential oil, according to the International Standards (ISO), can range in color from pale yellow to amber for Chinese ginger, yellow for Indian, and pale yellow to yellow for Nigerian.6 Note that Jamaican and Madagascan ginger are sought after for aromatherapy and are not detailed in the ISO standards.
The aroma of ginger essential oil is a characteristic peppery, almost sweet lemony aroma, but not the intense flavor of the spice. Nigerian ginger has a heavy, oily, woody aroma. Ginger oil will become thicker or resinified (to make or become a resin or resin-like) if exposed to air over a period of time. It should not feel thick, and this may indicate the oil is old. When you rub the oil between your fingers, it should feel thin and dry quickly. If you drop a few drops on a perfume blotter, it should not leave a darkened stain.
Solubility in alcohol is another effective way to evaluate the quality of an oil. If it deviates from the standards, it reveals it has been adulterated with an intentional or unintentional substance. Adulterated essential oils are best avoided. Ginger essential oil is only slightly soluble in 95% alcohol.
Other evaluation tests that require specialized equipment and expertise are specific gravity, optical rotation, and refractive index. Ginger essential oil has a specific gravity of 0.866-0.877 at 15˚C, and the International Standards range for the refractive index at 20˚C is 1.489-1.496, and the optical rotation range at 20˚C is between −47° and −26° for Chinese, between −50° and −27° for Indian and between −47° and −18° for West African. These are considered accepted values and are published by the ISO.7 If the ginger essential oil you buy is sourced from outside these ISO-listed countries, ensure that the optical rotation and other physical characteristics fall within the lowest and highest of the given ranges.
Ginger essential oil distilled from fresh ginger rhizomes will contain more curcumene, which the ISO lists as ranging from 3-11%. The sesquiterpenes zingiberene, alpha-curcumene, bisabolone, and farnesene dominate ginger essential oil. Zingiberene is the primary marker constituent and is known as the ginger-specific sesquiterpene hydrocarbon. The range should be between 23-45%. The range is dependent on the geographical location, and it should always be present and at the recommended levels. Australian ginger consists of mainly monoterpenes, such as camphene, phellandrene, and alcohols, such as geraniol and linalol. Vietnamese ginger contains more geraniol and is similar to the Indian variety. Jamaican ginger contains the aldehydes, neral, decyl aldehyde, delta-camphene, phellandrene, cineole, borneol, geraniol, gingerol, gamma-eudesmol, linalool, citral, methyl heptenone, chavicol, a sesquiterpene, zingiberene, and zingiberol, a sesquiterpene alcohol that provides the mild, characteristic aroma.
Nausea & Motion Sickness: While ginger essential oil has numerous notable therapeutic actions and medicinal uses, the antiemetic action is perhaps the best known. Motion and morning sickness are two uses that spring to our minds when we think of ginger for home use. However, during pregnancy, it is important to differentiate between dried ginger root, whole or powdered, and ginger essential oil. Ginger essential oil is not recommended for morning sickness.
Postoperative nausea and vomiting continue to be significant issues that can severely impact health and recovery in a hospital setting.8 Many pharmaceutical antiemetics can cause serious side effects. Researchers have been conducting clinical trials with ginger exploring the antinausea action in hospital settings for postoperative nausea and vomiting and for pre and post-cancer infusion therapy where a non-pharmaceutical antiemetic is needed. An older 2005 study showed that a 5% application of ginger essential oil to patients' wrists before general anesthesia prevented nausea in approximately 80% of treated patients.9
In 2012 the Department of Anesthesia at the Carolinas Medical Center University, Charlotte, North Carolina, performed a randomized trial of aromatherapy postoperative patients experiencing nausea. They were administered either an inhalation of ginger essential oil, an essential oil blend (ginger, peppermint Mentha ×piperita (L.), spearmint Mentha spicata (L.), and cardamom, or isopropyl alcohol. The number of antiemetic medications requested after aromatherapy was significantly reduced with ginger (P = 0.002) or aromatherapy blend (P < 0.001) versus saline. The researchers felt this confirmed aromatherapy as a viable treatment for postoperative nausea.10
Another study concluded that ginger-infused gauze pads provided nausea relief in approximately 67% of patients compared with 40% in the placebo group. Further, when ginger essential oil was blended with spearmint, peppermint, and cardamom, nausea relief increased to 82% of patients.11 A randomized placebo-controlled study conducted in 2019 explored the treatment potential of using ginger, lavender, and rose essential oils versus placebo for postoperative nausea and vomiting in patients. While 5,205 patients who met the eligibility criteria were accepted into the trial, not all experienced postoperative nausea and vomiting. The trial finally included 184 patients, who were said to have an excellent sense of smell. Two drops of either ginger, lavender, rose oil, or pure water were dropped onto a gauze pad, and the patient was asked to inhale the aroma for 5 minutes. Nausea and vomiting scores were evaluated at fifteen and again at forty minutes after the oils were inhaled. Results were statistically evident at 15 minutes and more significant at 40 minutes, with ginger and lavender showing a substantial reduction in nausea and vomiting compared to rose and the placebo.12
Anxiety & Depression: In the almost-post-pandemic world, depression and anxiety continue to manifest in all segments of the population. The World Health Organization (WHO) estimates the pandemic triggered a 25% increase in anxiety and depression worldwide. Young people and women were said to be the hardest hit.13 This overwhelming health crisis has manifested in many children and young adults with a marked increase in eating disorders such as anorexia, bulimia, and the less well-known subtype called avoidant restrictive food intake disorder (ARFID).14 Even though ARFID was added to the psychiatric nomenclature in 2013, little is known about its optimal treatment.15 Anxiety and nausea are associated with all types of eating disorders, but particularly with ARFID.16 Controlling nausea and subsequent loss of appetite associated with anxiety is a challenge. An individualized inhaler of ginger, lavender, chamomile, and bergamot essential oils could offer symptomatic relief.
Effective drug delivery system: Ginger essential oil may not be the first oil that comes to mind when we look for antifungal and antimicrobial actions. However, a very early study showed that ginger essential oil demonstrated good antibacterial activity against Staphylococcus aureus.17 A study in 2021 evaluated the potential for ginger and ginger essential oil in wound dressings.18 A hydrogel nanofiber release of fatty acids results in an undesirable acidic pH. The researchers found that the addition of antioxidant-rich ginger oil not only minimizes the oxidation of soy lecithin, but also provides antibacterial, antimocrobial activity against both Gram (-) and Gram (+) bacteria.19 Other studies have confirmed this antibacterial potential and reveal that ginger essential oils have the ability to inhibit Escherichia coli and Staphylococcus aureaus.20 The antibacterial activity of ginger essential oils is attributed to the constituents zingiberene, 𝜶-farnesene, 6-gingerol, and 𝜶-curcumene. Researchers have shown that these constituents attack microbial cell membranes and cell walls which causes intracellular components to leak from the cell resulting in cell death.21
Antifungal: The antifungal action of ginger is also of interest. Food-borne fungi such as Fusarium moniliforme, usually found in corn, are inhibited and destroyed by ginger essential oil and oleoresin.22 If food infected with Fusarium is eaten it can cause mycotoxicosis in immune-compromised people.23 An in vitro study in 2008 showed ginger essential oil to be effective against several fluconazole-resistant strains of Candida yeasts.24 Ginger reduced the growth and aflatoxin production of Aspergillus parasiticus when used in the concentration range of 100-300 ppm.25
Arthritis: For those with arthritis, ginger essential oil, oleoresin, and CO2 extract have demonstrated anti-inflammatory potential. Gingerols found in the essential oil and shogaols found in the oleoresin and CO2 extract inhibit the activation of several genes involved in the inflammatory response. Gingerols can also inhibit the synthesis of inflammation mediators such as prostaglandins and leukotrienes.26
Ginger’s toxic rating is I.27
A skin patch test is recommended for anyone with sensitive skin as it may cause irritation. This usually occurs when applied at full strength, which is not recommended. There have been reports of insignificant potential for photosensitivity; however, for anyone with sun sensitivity, exercise caution.
Sources:
1 Dafni, A., Benítez, G., & Khatib,, S. A. (2021). The Doctrine of Signatures in Israel-Revision and Spatiotemporal Patterns. . Plants (Basel, Switzerland), 10(7), 1346. Retrieved September 9, 2022, from https://pubmed.ncbi.nlm.nih.gov/34371549/
2 Supplement to earlier monographs on Fragrance Raw Materials. (1979). Monographs on Fragrance Raw Materials, 8–10. Retrieved September 9, 2022, from https://doi.org/10.1016/b978-0-08-023775-6.50011-4
3 Ibid.
4 CFR - Code of Federal Regulations Title 21. accessdata.fda.gov. (n.d.). Retrieved September 1, 2022, from https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=182.20
5 Zhang, L., Pan, C., Ou, Z., Liang, X., Shi, Y., Chi, L., Zhang, Z., Zheng, X., Li, C., & Xiang, H. (2020). Chemical profiling and bioactivity of essential oils from Alpinia officinarum Hance from ten localities in China. Industrial Crops and Products, 153, 112583. Retrieved September 9, 2022, from https://doi.org/10.1016/j.indcrop.2020.112583
6 “©ISO. The material is reproduced from ISO 16928:2014 permission of the American National Standards Institute (ANSI) on behalf of the International Organization for Standardization. All rights reserved.
7 Ibid.
8 Athavale, A., Athavale, T., & Roberts, D. M. (2020). Antiemetic drugs: what to prescribe and when. Australian prescriber, 43(2), 49–56. Retrieved September 8, 2022, from https://doi.org/10.18773/austprescr.2020.011
9 Geiger J. (2005). The essential oil of ginger and anaesthesia. International Journal Of Aromatherapy, 15(1), 7-14. Retrieved September 9, 2022, from https://doi.org/10.1016/j.ijat.2004.12.002
10 Hunt, R., Dienemann, J., Norton, H.J., Hartley, W., Hudgens, A., Stern, T., et al. (2012). Aromatherapy as Treatment for Postoperative Nausea: A Randomized Trial. Anesth Analg.
11 Hunt, R., Dienemann, J., Norton, H. J., Hartley, W., Hudgens, A., Stern, T., & Divine, G. (2013). Aromatherapy as treatment for postoperative nausea: a randomized trial. Anesthesia and Analgesia, 117(3), 597–604. Retrieved September 9, 2022, from https://doi.org/10.1213/ANE.0b013e31824a0b1c
12 Karaman, S., Karaman, T., Tapar, H., Dogru, S., & Suren, M. (2019). A randomized placebo-controlled study of aromatherapy for the treatment of postoperative nausea and vomiting. Complementary Therapies in Medicine, 42, 417–421. Retrieved September 9, 2022, from https://doi.org/10.1016/j.ctim.2018.12.019
13 Toniolo, J., Delaide, V., & Beloni, P. (2021). Effectiveness of inhaled aromatherapy on chemotherapy-induced nausea and vomiting: A systematic review. The Journal of Alternative and Complementary Medicine, 27(12), 1ute058–1069. Retrieved September 2, 2022, from https://doi.org/10.1089/acm.2021.0067
14 Williams, A. S., Dove, J., Krock, J. E., Strauss, C. M., Panda, S., Sinnott, L. T., & Rettig, A. E. (2022). Efficacy of Inhaled Essential Oil Use on Selected Symptoms Affecting Quality of Life in Patients With Cancer Receiving Infusion Therapies. Oncology nursing forum, 49(4), 349–358. Retrieved September 9, 2022, from https://doi.org/10.1188/22.ONF.349-358
15 Williams, A. S., Dove, J., Krock, J. E., Strauss, C. M., Panda, S., Sinnott, L. T., & Rettig, A. E. (2022). Efficacy of Inhaled Essential Oil Use on Selected Symptoms Affecting Quality of Life in Patients With Cancer Receiving Infusion Therapies. Oncology nursing forum, 49(4), 349–358. Retrieved September 9, 2022, from https://doi.org/10.1188/22.ONF.349-358
16 Saneei Totmaj, A., Emamat, H., Jarrahi, F., & Zarrati, M. (2019). The effect of Ginger (Zingiber officinale on chemotherapy‐induced nausea and vomiting in breast cancer patients: A systematic literature review of Randomized Controlled Trials. Phytotherapy Research, 33(8), 1957–1965. Retrieved September 9, 2022, from https://doi.org/10.1002/ptr.6377
17 Ibid.
18 Ryan, J. L., Heckler, C. E., Roscoe, J. A., Dakhil, S. R., Kirshner, J., Flynn, P. J., Morrow, G. R.(2012). Ginger (Zingiber officinale) reduces acute chemotherapy‐induced nausea: A URCC CCOP study of 576 patients. Supportive Care in Cancer, 20(7),1479–1489. Retrieved September 9, 2022, from https://doi.org/ 10.1007/s00520‐011‐1236‐3
19 Evans, A., Malvar, J., Garretson, C., Pedroja Kolovos, E., & Baron Nelson, M. (2018). The Use of Aromatherapy to Reduce Chemotherapy-Induced Nausea in Children With Cancer: A Randomized, Double-Blind, Placebo-Controlled Trial. Journal of pediatric oncology nursing : official journal of the Association of Pediatric Oncology Nurses, 35(6), 392–398. Retrieved September 14, 2022, from https://doi.org/10.1177/1043454218782133
20 Khiewkhern, S., Promthet, S., Sukprasert, A., Eunhpinitpong, W., & Bradshaw, P. (2013). Effectiveness of aromatherapy with light thai massage for cellular immunity improvement in colorectal cancer patients receiving chemotherapy. Asian Pacific journal of cancer prevention : APJCP, 14(6), 3903–3907. Retrieved September 14, 2022 from, https://doi.org/10.7314/apjcp.2013.14.6.3903
21 World Health Organization. (n.d.). Covid-19 pandemic triggers 25% increase in prevalence of anxiety and depression worldwide. World Health Organization. Retrieved September 15, 2022, from https://www.who.int/news/item/02-03-2022-covid-19-pandemic-triggers-25-increase-in-prevalence-of-anxiety-and-depression-worldwide
22 Gao, Y., Bagheri, N., & Furuya-Kanamori, L. (2022, March 29). Has the COVID-19 pandemic lockdown worsened eating disorders symptoms among patients with eating disorders? A systematic review. Zeitschrift fur Gesundheitswissenschaften = Journal of public health. Retrieved September 15, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8961480/
23 Thomas, J. J., Wons, O. B., & Eddy, K. T. (2018). Cognitive-behavioral treatment of avoidant/restrictive food intake disorder. Current Opinion in Psychiatry, 31(6), 425–430. Retrieved September 15, 2022, from https://doi.org/10.1097/YCO.0000000000000454
24 Burton Murray, H., Jehangir, A., Silvernale, C. J., Kuo, B., & Parkman, H. P. (2020). Avoidant/restrictive food intake disorder symptoms are frequent in patients presenting for symptoms of gastroparesis. Neurogastroenterology &; Motility, 32(12). Retrieved September 15, 2022, from https://doi.org/10.1111/nmo.13931
25 Ontengco, D.C., Dayap, L.A., & Capal, T.V. (1995). Screening for the antibacterial activity of essential oils from some Philippine plants. Acta Manilana, 43:19-23.
26 Squinca, P., Berglund, L., Hanna, K., Rakar, J., Junker, J., Khalaf, H., Farinas, C. S., & Oksman, K. (2021). Multifunctional Ginger Nanofiber Hydrogels with Tunable Absorption: The Potential for Advanced Wound Dressing Applications. Biomacromolecules, 22(8), 3202–3215. Retrieved September 15, 2022, from https://doi.org/10.1021/acs.biomac.1c00215
27 Quach, H., Le, T. V., Nguyen, T. T., Nguyen, P., Nguyen, C. K., & Dang, L. H. (2022). Nano-Lipids Based on Ginger Oil and Lecithin as a Potential Drug Delivery System. Pharmaceutics, 14(8), 1654. Retrieved September 15, 2022, from https://doi.org/10.3390/pharmaceutics14081654
28 Wang, X., Shen, Y., Thakur, K., Han, J., Zhang, J. G., Hu, F., & Wei, Z. J. (2020). Antibacterial Activity and Mechanism of Ginger Essential Oil against Escherichia coli and Staphylococcus aureus. Molecules (Basel, Switzerland), 25(17), 3955. Retrieved September 15, 2022, from https://doi.org/10.3390/molecules25173955
29 Wang, X., Shen, Y., Thakur, K., Han, J., Zhang, J. G., Hu, F., & Wei, Z. J. (2020). Antibacterial Activity and Mechanism of Ginger Essential Oil against Escherichia coli and Staphylococcus aureus. Molecules (Basel, Switzerland), 25(17), 3955. Retrieved September 15, 2022, from https://doi.org/10.3390/molecules25173955
30 Singh, G., Kapoor, I. P., Singh, P., de Heluani, C. S., de Lampasona, M. P., & Catalan, C. A. (2008). Chemistry, antioxidant and antimicrobial investigations on essential oil and oleoresins of Zingiber officinale. Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 46(10), 3295–3302. Retrieved September 15, 2022, from https://doi.org/10.1016/j.fct.2008.07.017
31 Gupta, A. K., Baran, R., & Summerbell, R. C. (2000). Fusarium infections of the skin. Current opinion in infectious diseases, 13(2), 121–128. Retrieved September 15, 2022, from https://doi.org/10.1097/00001432-200004000-00005
32 Pozzatti, P., Scheid, L.A., Spader, T.B., Atayde, M.L., Santurio, J.M., & Alves, S.H. (2008). In vitro activity of essential oils extracted from plants used as spices against fluconazole-resistant and fluconazole-susceptible Candida spp. Can J Microbiol., 54(11):950-6.
33 Tiwari, R., Dikshit, R.P., Chandan, N.C., Saxena, A., Gupta, K.G., & Vadehra D.E. (1983). Inhibition of Growth and Aflatoxin B1 Production of Aspergillus parasiticus by Spice Oils. J Fd Sci Technol, 20:131-132.
34 Ramadan, G., Al-Kahtani, M. A., & El-Sayed, W. M. (2011). Anti-inflammatory and anti-oxidant properties of Curcuma longa (turmeric) versus Zingiber officinale (ginger) rhizomes in rat adjuvant-induced arthritis. Inflammation, 34(4), 291–301. Retrieved September 15, 2022, from https://doi.org/10.1007/s10753-010-9278-0
35 ACHS.edu Toxic Rating: I = Low, II = Moderate, III = High (Low Therapeutic Margin)