gingerol and alpha-curcumene

Severe flooding of the Brahmaputra River during the monsoon season and continuous rainfall in the northeast region (NER) of India cause an enormous loss of ginger crop every year. In this context, the present study investigates the variation in the essential oil composition and oleoresin and [6]-gingerol contents in 10 different fresh ginger cultivars harvested at 6- and 9-month maturity from five different states of NER. Monoterpenes, sesquiterpenes, and citral composition in the essential oil were evaluated to ascertain their dependence upon the maturity of ginger. Except Mizoram Thinglaidum, Mizoram Thingria, Nagaland Nadia, and Tripura I ginger cultivars, all other cultivars showed an increase in the citral content during the maturity that was observed for the first time. At 6-month maturity, a higher undecanone level was found in Nagaland Nadia (7.36 ± 0.61%), Tripura I (6.23 ± 0.61%), and Tripura III (9.17 ± 0.76%) cultivars, and these data can be used as a benchmark to identify those immature varieties. Interestingly, the Nagaland Nadia cultivar showed higher ar-curcumene (9.57 ± 0.58%) content than zingiberene (5.84 ± 0.24%), which was unique among all cultivars. Ginger harvested at 9-month maturity from the Tripura II cultivar had the highest citral content (22.03 ± 0.49%), and the Meghalaya Mahima cultivar had the highest zingiberene content (29.89 ± 2.92%). The oleoresin content was found to decrease with maturity in all cultivars, except Assam Fibreless and Manipur I. Moreover, the highest oleoresin (11.43 ± 0.58 and 9.42 ± 0.63%) and [6]-gingerol (1.67 ± 0.03 and 1.67 ± 0.05 g) contents were observed for Tripura II and Nagaland Nadia, respectively. This study suggests that Tripura and Nagaland are the most ideal locations in NER for ginger cultivation to obtain high yields of oleoresin and [6]-gingerol contents and harvesting at the 6-month maturation will compensate for the loss of ginger crop caused by the Brahmaputra River flooding in NER every year.

Topics: Acyclic Monoterpenes; Catechols; Chromatography, High Pressure Liquid; Cluster Analysis; Fatty Alcohols; Gas Chromatography-Mass Spectrometry; India; Monocyclic Sesquiterpenes; Monoterpenes; Oils, Volatile; Plant Extracts; Sesquiterpenes; Zingiber officinale

The proinflammatory chemokine interleukin-8 is increased in asthmatic patients. Traditionally, ginger is used as an antiinflammatory drug. An extract and several compounds of Zingiber officinale (ginger) were tested in human bronchial epithelial cells (BEAS-2B cells) with respect to their effect on lipopolysaccharide (LPS)-induced secretion of the proinflammatory chemokine interleukin 8 (IL-8) and RANTES (regulated upon activation, normal T-cell expressed and secreted). An oily extract of ginger rhizome with > 25% total pungent compounds, ginger volatile oil, ar-curcumene and α-pinene reduced the LPS-induced IL-8 secretion (measured by a specific enzyme-linked immunosorbent assay), whereas a spissum extract, the pungents [6]-gingerol and its metabolite [6]-shogaol, and the terpenoids citral and β-phellandrene showed no effect. The LPS-induced slight increase of RANTES was reduced by volatile oil, ar-curcumene and α-pinene. There was no effect of LPS on TNF-α. Our results suggest that distinct ginger compounds could be used as antiinflammatory drugs in respiratory infections.

Topics: Anti-Inflammatory Agents; Bicyclic Monoterpenes; Bronchi; Catechols; Cell Line; Chemokine CCL5; Cyclohexane Monoterpenes; Cyclohexenes; Dose-Response Relationship, Immunologic; Enzyme-Linked Immunosorbent Assay; Epithelial Cells; Fatty Alcohols; Humans; Interleukin-8; Lipopolysaccharides; Monoterpenes; Plant Extracts; Plant Oils; Pseudomonas aeruginosa; Rhizome; Sesquiterpenes; Volatile Organic Compounds; Zingiber officinale