Influence of Cultivar and Maturity at Harvest on the Essential Oil Composition, Oleoresin and [6]-Gingerol Contents in Fresh Ginger from Northeast India

Abstract

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.

Anti-inflammatory effects of the essential oils of ginger (Zingiber officinale Roscoe) in experimental rheumatoid arthritis

“…Sesquiterpenes are major constituents of the essential oils of turmeric (ar-turmerone, α-turmerone and ß-turmerone) 10 and ginger (zingiberene and ar-curcumene) [34-43], while the monoterpene isomers, neral and geranial, collectively referred to as citral, are only present in GEO and comprise a variable but significant amount by weight (16-75%) [35,37,39-43]. Because estrogenic effects have been reported previously for citral in vitro [17,18], including low affinity estrogen receptor (ER) binding and estrogenic activity, the in vivo effects of GEO were compared to those of 17ß-estradiol in the SCW model.…”

Perspectives and Applications of Natural Products as Civilian Defense Devices

“…The levels of 6-gingerol decrease as the specimen reaches maturity, with concentrations varying between 0.95 and 30.0 g per 100 g of fruit. 61,66 These levels are lower than those found in capsaicin in Capsicum annuum cayenne (main variety used in NLW manufacturing) ( Table 1), evidencing that in economic terms, it would still be necessary to evaluate varieties with high levels of the major pungent compound.…”

“…[58][59][60] The rhizome of ginger corresponds to the portion usually used in the preparation of these natural products, presenting from 1 to 7.5% of its weight in volatile compounds and pungent substances. 61 The pungent compounds present in ginger are the gingerols and correspond to approximately 33% of the weight of the Zingiber oleoresin. The major pungent compound present in these rhizomes is the 6-gingerol, which is considered an economically important substance, not only because of its pungency but also because it was reported to present anticarcinogenic and antitumor activities, among others.…”

“…60 Worldwide cultivation of this botanical species has led to the development of varieties that better adapt to each ecosystem, generating the formation of an intraspecific variability within the species of Zingiber similar to those from Capsicum, where within the same species can be found cultivars with different chemical profiles. 61,64,65 The maturation stage is also one of the factors capable of changing the contents of the pungent compounds in ginger. The levels of 6-gingerol decrease as the specimen reaches maturity, with concentrations varying between 0.95 and 30.0 g per 100 g of fruit.…”

Pigment Composition Responsible for the Pale Yellow Color of Ginger (Zingiber officinale) Rhizomes

“…Previously, differences in metabolite profiles between immature and mature ginger were estimated from volatiles and pungent compounds (Sakamura, 1987;Sekiwa-Iijima et al, 2001;BaileyShaw et al, 2008;Kiran et al, 2013). However, differences in the accumulation of yellow pigments have not been clarified.…”