Table 2.

The biological activities and molecular mechanisms of red ginger.

Bioactivity	Mechanism	Responsible Constituents	Ref.
Antimicrobial activity	Anti-gram negative Anti-gram positive Natural preservative	β-caryophyllene	[33]
Analgesic activity	Hyperalgesia↓ γ-aminobutyric acid↓ NR2B↓	Camphene Cineole Geranial Geranyl acetate	[34,35,36]
Antidiabetic activity	α-amylase α-glucosidase	Gingerols shogaols	[37]
Anti-inflammatory	Prostaglandins↓ leukotrienes↓ COX-1↓ COX-2↓ 5-LO↓ TNF-α↓ NO↓ iNOS↓ NF-κb↓ TPA↓ ODC↓	6-gingerol 6-shogaol 8-gingerol 10-gingerol	[19,38,39,40,41,42]
Antioxidant	Donating electrons or a hydrogen atom to free radical	Phenolic compounds Quercetin 6-shogaol 8-shogaol 6-gingerol 8-gingerol 10-gingerol	[19,43,44,45]
Melanogenesis inhibitory activity	Melanogenesis inhibitory activity	Gingerdione	[25]
Anticancer and antitumor activity	Angiogenesis and metastasis	6-shogaol 6-gingerol	[46,47,48,49,50,51]
Antihyperlipidemic	LDL-C↓ ACE↓ HDL-C↓ malondialdehyde↓	Gingerol Shogaol Gingerdione	[52,53]
Anti-hypercholesterolemia	LDL↑, HMG-CoA↑, HDL↑	Phenolic compounds	[54]
Antihypertensive	NO↑ Prostacyclin Release Ca2+ Activation of cGMP-KATP Stimulation of muscarinic receptors	6-gingerol 6-shogaol gingerdione	[30]
Anti-Alzheimer’s disease	HDAC↓, Trichostatin A↓, MS275↓, AChE↑, α-secretase↓, Aβ-42↓, β-secretase↓, APH1a↑	Flavonoids Tannins Alkaloids 6-shogaol terpenoids	[20,53,55,56,57,58]
Androgenic effect	Pre-leptotene↑, pachytene spermatocytes↑	Arginine Shogaol Gingerdiol Gingerol Zingerone Zingiber	[59,60,61]
Insecticidal activity	Zingerone and benzaldehyde dimethyl thiol acetal	Zingerone Benzaldehyde dimethyl thiol acetal	[62]
Immunomodulatory	Recover small intestine mucosa structure of mice Protective effect on dopaminergic neurons	Phenols	[63]