Application of Chromatographic and Spectroscopic Methods towards the Quality Assessment of Ginger (Zingiber officinale) Rhizomes from Ecological Plantations

Abstract

The usefulness of ginger in the food industry and pharmacotherapy is strictly related to its content of various components. The study elucidates the chemical composition of Zingiber officinale rhizomes cultivated on ecological plantations on Shikoku Island (Japan). GC-MS analysis of terpene content, LC-MS determination of phenolic content, and the determination of 12 elements using AAS spectrometry were performed to give more detailed insight into the samples. Ninety-five percent of terpene composition was elucidated, with zingiberene as the most abundant sesquiterpene (37.9%); the quantification of gingerols and shogaols was performed, showing the highest contribution of 6-gingerol (268.3 mg/kg); a significant K (43,963 mg/kg of dry mass) and Mn (758.4 mg/kg of dry mass) content was determined in the elemental analysis of the rhizomes and low concentration of toxic elements (Cd, Ni and Pb) remaining below the safe level values recommended by European Commission Directives. The main phenolic compound was (6)-gingerol, which is characteristic of fresh rhizomes and is responsible for their taste and aroma. Surprisingly, high amounts of (6)-shogaol were determined, even though this phenolic compound usually occurs in old or processed material and not in fresh rhizomes. Sesquiterpenes were the major fraction of volatiles. The highest concentrations were determined for α-zingiberene, β-sesquiphellandrene, (E,E)-α-farnesene, geranial, and ar-curcumene. The volatiles composition of ginger cultivated on Shikoku Island is specific and strongly differs from plants cultivated in China, Nigeria, or Australia. The elemental composition of ginger rhizomes grown in ecological plantations is more beneficial for human health compared to products grown in normal cultivars, as the products contain high amounts of potassium and manganese and are characterized by low sodium content and lower levels of toxic heavy metals.

MAO-A Inhibitory Potential of Terpene Constituents from Ginger Rhizomes—A Bioactivity Guided Fractionation

“…The constituents of ginger’s rhizome may be divided into two major groups: lipids and oleoresins. The latter—rich in secondary metabolites—is composed of terpenes (monoterpenes, sesquiterpenes, and sesquiterpene alcohols) in 20–25% and of phenolics–gingerols (including gingerodiones, gingerdiols, dehydrogingerdiones, and diarylheptanoids), which account for another 25% of the semi-liquid resin [ 9 , 31 , 32 ].…”

“…A GC-MS based qualitative analysis was performed on the three collective samples prior to further fractionation. Several compounds, which belonged to the group of terpenes were identified based on their retention indices, literature data and previous studies of the authors [ 32 ]. The identification data of major constituents are presented in Table 1 .…”

“…10 µL of each sample was directly injected to a gas chromatograph (GC) (Agilent Technologies 4890N, Santa Clara, CA, USA) equipped in a capillary column HP-5MS (30 m, 0.25 mm × 0.26) and in an MS detector (Agilent Technologies 5973, Santa Clara, LA, USA) using a Hamilton syringe. The analysis was performed in a temperature-dependant method according to the previously published methodology [ 32 ]. Briefly, the inlet temperature was set at 250 °C, the initial temperature at 50 °C, the final temperature at 250 °C, and the heating ramp was set as 5 °C/min.…”

Antivirulence properties and related mechanisms of spice essential oils: A comprehensive review

“…Although spice essential oils are generally safe when used in moderate amounts, some of these highly concentrated oils may irritate skin and mucous membranes, induce epilepsy, or show toxic effects in excessive dosages, especially in children who are particularly susceptible (Halicioglu, Astarcioglu, Yaprak, & Aydinlioglu, 2011; Vigan, 2010). The pharmacological benefits of spice essential oils gain more and more attention, such as their antiinfective, anticancer, antipyretic, and carminative effects (Hosseini, Nadjafi, Asareh, & Rezadoost, 2018; Koch et al., 2017). These characteristics of essential oils are strongly related to the bioactive phytochemical composition, and this composition is an important parameter for evaluating the quality of essential oils and potential application prospects.…”

Effect of ginger (Zingiber officinale) on semen quality

“…Rather than the many phytochemicals in ginger that has been found to have various biological and health benefits, in 2017, a study by Koch et al, showed that ginger rhizomes contain significant amounts of certain nutrients, particularly manganese. Such finding would be imperative when discussing the impact of ginger on semen quality, in which manganese supplementation was found to enhance luteinising hormone secretion in male rats (Lee et al, ).…”