Ginger (Zingiber officinale Roscoe) or ginger root is the rhizome of a perennial medicinal plant of the Zingiberaceae family. It is one of the world’s most commonly consumed dietary condiments and herbal medicines. Ginger was used as a flavoring agent and aphrodisiac long before history was formally recorded.
Ginger root has been mentioned in traditional Ayurvedic and Chinese medical literature. Indians and Chinese have used ginger as a tonic root for thousands of years to treat numerous ailments, such as headaches, colds, nausea, arthritis, migraine, and hypertension.
Ginger is a member of a plant family that includes cardamom and turmeric. It is cultivated throughout the humid tropics, with Southeast Asian countries being the largest producer.
We consume the rhizome, the horizontal stem from which the roots grow. Ginger is recognized as a ”safe food additive” by the U.S. Food and Drug Administration (FDA).
The spicy aroma of fresh ginger is mainly due to the presence of ketones, especially gingerols. 6- gingerol is a phenolic alkanone with a pungent smell found in fresh ginger. Pungency of dry ginger is caused by shogaols, a dehydrated form of gingerols formed when ginger is dried or cooked. The flavor is peppery and slightly sweet, with a solid and spicy aroma.
Gingerols are converted into shogaols during heat treatment. The oleoresin (i.e., oily resin) from the rhizomes of ginger contains many bioactive components, such as 6-gingerol, which provides various health benefits.
Though ginger is especially valued for its medicinal properties, ginger root has been used for centuries worldwide in preparing cuisine. Ginger is used in numerous forms, including fresh, dried, pickled, preserved, crystallized, candied, and powdered or ground.
Ginger root contains various chemical constituents, including phenolic compounds, terpenes, carbohydrates, lipids, and dietary fibers. (1) The health benefits of ginger are mainly attributed to its phenolic compounds, such as gingerols, shogaols, and paradols.
Other phenolic compounds found in ginger are;
- Quercetin
- Zingerone
- Gingerenone-A
- 6-dehydrogingerdione
Ginger contains several terpene components, the main constituents of ginger essential oils. They are;
- β-bisabolene
- α-curcumene
- Zingiberene
- α-farnesene
- β-sesquiphellandrene
The medicinal, chemical and pharmacological properties of ginger have been extensively reviewed. Ginger possesses multiple biological activities such as antioxidant, anti-inflammatory, antimicrobial, anticancer, antiobesity, antidiabetic, anti-nausea, and antiemetic. It also provides neuroprotective, cardiovascular protective, and respiratory protective activities.
Ginger has the potential to be developed into functional foods or nutraceuticals for the prevention and management of chronic diseases.
1. Antioxidants
Reactive oxygen species (ROS) play an important part in developing many chronic diseases. (2) Several in vitro and in vivo studies have demonstrated that ginger and its bioactive compounds, such as 6-shogaol, 6-gingerol, and oleoresin, possess potent antioxidant activity and effectively protect against oxidative stress. (3,4)
Dried-ginger has the strongest antioxidant activity compared to fresh, stir-fried, and carbonized ginger. (5)
2. Anti-inflammatory
Ginger and its active constituents, such as 6-shogaol, 6-gingerol, 6-dehydroshogaol, zingerone, and ginger extract, possess anti-inflammatory activity, which could alleviate inflammation and protect against inflammation-related diseases such as colitis. (6,7) Applying ginger nanoparticles can improve the prevention and therapy for inflammatory bowel disease. (6)
3. Antimicrobial Activity
Ginger and ginger essential oil have been reported to show antibacterial, antifungal, and antiviral activities. (8) Lipophilic properties of ginger essential oil and bioactive components such as γ-terpinene and citral showed potent antifungal activities. (9) Antimicrobial effects of ginger could be mainly related to the suppression of bacterial biofilm formation, ergosterol biosynthesis in fungi, and attachment and internalization of viruses. (9)
4. Cytotoxicity
Ginger has been widely investigated for its anticancer properties against different cancer types, such as breast, cervical, colorectal, and prostate cancer. Ginger phytochemicals provide anticancer activity mainly via the induction of apoptosis and the inhibition of the proliferation of cancer cells.
Bioactive compounds (polyphenols) in ginger shown to interfere the carcinogenic processes of colorectal cancer and gastric adenocarcinoma. (10)
Ginger phytochemicals such as 6-gingerol, 10-gingerol, 6-shogaol, and 10-shogaol showed an anti-proliferative effect on human prostate cancer cells. (11)
Ginger extract, 6-shogaol, and 10-gingerol also exhibit cytotoxic activity against other types of cancer, such as breast, cervical, liver, and pancreatic cancer. (12,13)
5. Neuroprotection
Many investigations have revealed that ginger positively affects memory function and exhibits anti-neuroinflammatory activity, which might contribute to the management and prevention of neurodegenerative diseases such as Alzheimer’sAlzheimer’s disease and Parkinson’sParkinson’s disease. (14)
The antioxidant and anti-inflammatory activities of ginger and its bioactive compounds, such as 10-gingerol, 6-shogaol, and 6-dehydrogingerdione contribute to neuroprotection. (14,15)
6. Cardiovascular Protection
Dyslipidemia and hypertension are known to be risk factors for cardiovascular diseases, including stroke and coronary heart disease.
Ginger extracts exhibit cardiovascular protection by attenuating hypertension and ameliorating dyslipidemia. A series of studies have shown that ginger extract can decrease blood lipids and blood pressure levels. (16–18)
7. Antiobesity Activity
Obesity is a risk factor for many chronic diseases, such as diabetes, hypertension, and cardiovascular diseases.
Several studies have reported that bioactive constituents in ginger, such as gingerenone A, 6-Shogaol, and 6-gingerol are effective in managing and preventing obesity. These compounds inhibit adipogenesis and enhance fatty acid catabolism. (19,20)
8. Antidiabetic Activity
Many research works have demonstrated that ginger and its bioactive compounds, such as 6-shogaol and 6-gingerol could protect against diabetes mellitus and its complications, probably by increasing the sensitivity and decreasing the insulin level. (5)
9. Antiemetic Activity
Research has demonstrated that ginger could effectively alleviate motion sickness, nausea, and vomiting. An in vitro experiment showed that 6-shogaol, 6-gingerol, and zingerone inhibited emetic signal transmission and attenuated nausea and emesis in various conditions such as pregnancy and chemotherapy. (21)
10. Protective Effect against Respiratory Disorders
Ginger and its bioactive compounds, such as 6-gingerol, 8-gingerol, 6-shogaol, citral, and eucalyptol have exhibited bronchodilating activity and antihyperactivity in several studies. They induce relaxation in airway smooth muscle and attenuate airway resistance and inflammation. (22,23)
11. Other Bioactivities
Apart from the beneficial health effects mentioned above, ginger has other health benefits, such as hepatoprotective and antiallergic effects.
Ginger and its bioactive compound, 6-gingerol suppresses cytokine production and mast cell activation, preventing or alleviating allergic rhinitis. (24)
References
1. FoodData Central [Internet]. [cited 2022 Dec 17]. Available from: https://fdc.nal.usda.gov/fdc-app.html#/food-details/169231/nutrients
2. Poprac P, Jomova K, Simunkova M, Kollar V, Rhodes CJ, Valko M. Targeting Free Radicals in Oxidative Stress-Related Human Diseases. Trends Pharmacol Sci. 2017 Jul;38(7):592–607.
3. Abolaji AO, Ojo M, Afolabi TT, Arowoogun MD, Nwawolor D, Farombi EO. Protective properties of 6-gingerol-rich fraction from Zingiber officinale (Ginger) on chlorpyrifos-induced oxidative damage and inflammation in the brain, ovary and uterus of rats. Chem Biol Interact. 2017 May 25;270:15–23.
4. Ji K, Fang L, Zhao H, Li Q, Shi Y, Xu C, et al. Ginger Oleoresin Alleviated γ-Ray Irradiation-Induced Reactive Oxygen Species via the Nrf2 Protective Response in Human Mesenchymal Stem Cells. Oxid Med Cell Longev. 2017;2017:1480294.
5. Mao QQ, Xu XY, Cao SY, Gan RY, Corke H, Beta T, et al. Bioactive Compounds and Bioactivities of Ginger (Zingiber officinale Roscoe). Foods. 2019 May 30;8(6):185.
6. Edible ginger-derived nanoparticles: A novel therapeutic approach for the prevention and treatment of inflammatory bowel disease and colitis-associated cancer – PubMed [Internet]. [cited 2022 Dec 17]. Available from: https://pubmed.ncbi.nlm.nih.gov/27318094/
7. Glutathione conjugation attenuates biological activities of 6-dehydroshogaol from ginger – PubMed [Internet]. [cited 2022 Dec 17]. Available from: https://pubmed.ncbi.nlm.nih.gov/23578607/
8. Nassan MA, Mohamed EH. Immunopathological and antimicrobial effect of black pepper, ginger and thyme extracts on experimental model of acute hematogenous pyelonephritis in albino rats. Int J Immunopathol Pharmacol. 2014;27(4):531–41.
9. Inhibitory effects of three monoterpenes from ginger essential oil on growth and aflatoxin production of Aspergillus flavus and their gene regulation in aflatoxin biosynthesis | Applied Biological Chemistry | Full Text [Internet]. [cited 2022 Dec 17]. Available from: https://applbiolchem.springeropen.com/articles/10.1007/s13765-018-0352-x
10. Antioxidant, enzyme inhibitory and antiproliferative activity of polyphenolic‐rich fraction of commercial dry ginger powder – Sakulnarmrat – 2015 – International Journal of Food Science & Technology – Wiley Online Library [Internet]. [cited 2022 Dec 17]. Available from: https://ifst.onlinelibrary.wiley.com/doi/abs/10.1111/ijfs.12889
11. Liu CM, Kao CL, Tseng YT, Lo YC, Chen CY. Ginger Phytochemicals Inhibit Cell Growth and Modulate Drug Resistance Factors in Docetaxel Resistant Prostate Cancer Cell. Mol Basel Switz. 2017 Sep 5;22(9):1477.
12. Zhang F, Zhang JG, Qu J, Zhang Q, Prasad C, Wei ZJ. Assessment of anti-cancerous potential of 6-gingerol (Tongling White Ginger) and its synergy with drugs on human cervical adenocarcinoma cells. Food Chem Toxicol Int J Publ Br Ind Biol Res Assoc. 2017 Nov;109(Pt 2):910–22.
13. Akimoto M, Iizuka M, Kanematsu R, Yoshida M, Takenaga K. Anticancer Effect of Ginger Extract against Pancreatic Cancer Cells Mainly through Reactive Oxygen Species-Mediated Autotic Cell Death. PloS One. 2015;10(5):e0126605.
14. 6-Shogaol, an active compound of ginger, protects dopaminergic neurons in Parkinson’s disease models via anti-neuroinflammation – PubMed [Internet]. [cited 2022 Dec 17]. Available from: https://pubmed.ncbi.nlm.nih.gov/23811724/
15. Yao J, Ge C, Duan D, Zhang B, Cui X, Peng S, et al. Activation of the phase II enzymes for neuroprotection by ginger active constituent 6-dehydrogingerdione in PC12 cells. J Agric Food Chem. 2014 Jun 18;62(24):5507–18.
16. Khosravani M, Azarbayjani MA, Abolmaesoomi M, Yusof A, Zainal Abidin N, Rahimi E, et al. Ginger extract and aerobic training reduces lipid profile in high-fat fed diet rats. Eur Rev Med Pharmacol Sci. 2016 Apr;20(8):1617–22.
17. de Las Heras N, Valero-Muñoz M, Martín-Fernández B, Ballesteros S, López-Farré A, Ruiz-Roso B, et al. Molecular factors involved in the hypolipidemic- and insulin-sensitizing effects of a ginger (Zingiber officinale Roscoe) extract in rats fed a high-fat diet. Appl Physiol Nutr Metab Physiol Appl Nutr Metab. 2017 Feb;42(2):209–15.
18. Akinyemi AJ, Thomé GR, Morsch VM, Bottari NB, Baldissarelli J, de Oliveira LS, et al. Dietary Supplementation of Ginger and Turmeric Rhizomes Modulates Platelets Ectonucleotidase and Adenosine Deaminase Activities in Normotensive and Hypertensive Rats. Phytother Res PTR. 2016 Jul;30(7):1156–63.
19. Misawa K, Hashizume K, Yamamoto M, Minegishi Y, Hase T, Shimotoyodome A. Ginger extract prevents high-fat diet-induced obesity in mice via activation of the peroxisome proliferator-activated receptor δ pathway. J Nutr Biochem. 2015 Oct;26(10):1058–67.
20. Miyamoto M, Matsuzaki K, Katakura M, Hara T, Tanabe Y, Shido O. Oral intake of encapsulated dried ginger root powder hardly affects human thermoregulatory function, but appears to facilitate fat utilization. Int J Biometeorol. 2015 Oct;59(10):1461–74.
21. Palatty PL, Haniadka R, Valder B, Arora R, Baliga MS. Ginger in the prevention of nausea and vomiting: a review. Crit Rev Food Sci Nutr. 2013;53(7):659–69.
22. Effects of ginger and its constituents on airway smooth muscle relaxation and calcium regulation – PubMed [Internet]. [cited 2022 Dec 17]. Available from: https://pubmed.ncbi.nlm.nih.gov/23065130/
23. Mangprayool T, Kupittayanant S, Chudapongse N. Participation of citral in the bronchodilatory effect of ginger oil and possible mechanism of action. Fitoterapia. 2013 Sep;89:68–73.
24. Kawamoto Y, Ueno Y, Nakahashi E, Obayashi M, Sugihara K, Qiao S, et al. Prevention of allergic rhinitis by ginger and the molecular basis of immunosuppression by 6-gingerol through T cell inactivation. J Nutr Biochem. 2016 Jan;27:112–22.