Bioactive Compounds and Biological Activities of Ginger Extract

Ginger (Zingiber officinale Roscoe) is one of the most commonly used spice. Ginger extract is rich in a variety of chemical constituents, including phenolic compounds, terpenes, polysaccharides, organic acids, and lipids. Its health benefits are mainly attributed to its phenolic compounds, such as shogaols and gingerols. Studies have shown that ginger extract possesses a wide range of biological activities including antimicrobial, antioxidant, anti-inflammatory, anticancer, anti-obesity, antidiabetic, cardiovascular protective, respiratory protective, anti-nausea and antiemetic activities.

• The volatile components
  The volatile active components are mainly monoterpenes and sesquiterpene alkenes, of which the higher contents are zingiberene, curcumene and farnesene, in addition to a certain amount of α-citral, bisabolene and so on.

• The non-volatile components
  The non-volatile components are the main active parts in ginger extracts. Among them, gingerols is considered to be the main active substance in ginger extract, including 6-gingerol, 8-gingerol, and 10-gingerol.

What are the biological activities of ginger extract?

Biological activities of ginger extract are mainly as follows.

• Antimicrobial activity
  Ginger extract has been shown to inhibit the growth of different viruses, bacteria and fungi. These effects may be mainly related to the inhibition of viral attachment and internalization, bacterial biofilm formation, and ergosterol biosynthesis.

• Antioxidant activity
  Studies have shown that bioactive compounds in ginger extract, such as 6- shogaol, 6-gingerol and oleoresin, have strong antioxidant activity. They work by increasing gene expression of antioxidant enzymes, reducing reactive oxygen species and lipid peroxidation levels, etc.

• Anti-inflammatory activity
  It has been reported that ginger extract is effective in alleviating inflammation, especially inflammatory bowel diseases. The anti-inflammatory mechanisms of it has been probably associated with the suppression of protein kinase B and nuclear factor kappa B activation, enhancement of anti-inflammatory cytokines and reduction of pro-inflammatory cytokines.

• Anticancer activity
  Studies have demonstrated that ginger extract can be used to prevent and treat many types of cancer, such as colorectal, breast, cervical, prostate, and pancreatic cancers. The anti-cancer mechanisms primarily involve inducing apoptosis and inhibiting proliferation of cancer cells.

• Anti-obesity activity
  Bioactive components in ginger extract, including gingerenone A, 6-gingerol and 6- shogaol, have shown anti-obesity activity. The mechanisms of them are mainly related to the inhibition of adipogenesis and the enhancement of fatty acid catabolism.

• Antidiabetic activity
  Ginger extract may prevent diabetes and its complications, probably by decreasing insulin levels but increasing insulin sensitivity.

• Cardiovascular protective activity
  Ginger extract exhibits cardiovascular protection by attenuating hypertension and ameliorating dyslipidemia. It works through enhancing the level of serum high-density lipoprotein-cholesterol, decreasing the concentrations of total cholesterol, low density lipoprotein and very low-density lipoprotein.

• Respiratory protective activity
  Bioactive compounds in ginger extract, including 6-gingerol, 8-gingerol, 6-shogaol, show protective effects against respiratory disorders. They act by inducing relaxation of airway smooth muscle and reducing of airway resistance and inflammation.

• Antinausea and antiemetic activities
  Ginger extract has potential efficacy of preventing and treating of nausea and vomiting of various origins. These effects are mainly due to the presence of gingerols and shogaols in ginger extract, which accelerate gastric emptying and stimulate sinus contractions, thereby relieving nausea and vomiting.