Effects of Steaming and Air-Drying on Ginsenoside Composition of Korean Ginseng (Panax ginseng C.A. Meyer)

Abstract

This study aimed to compare the ginsenosides composition of ginseng depending on cultivated region and processing method. Fresh ginseng roots collected from four major regions of Korea were processed using either air‐drying or steaming, and subsequent air‐drying. Five ginsenosides including Rg1, Re, Rb1, Rc and Rb2 were the major forms in fresh ginseng, whereas Rb1 and Rg1 were abundant in processed ginsengs. The contents of total ginsenoside decreased with thermal processing and also showed a regional difference between processed ginsengs, whereas fresh ginseng had a regional variation only in Rg1. Unlike another ginsenosides decreased by processing, Rb1 increased with thermal processing. Ginsengs with relatively much higher content of Rc in fresh ginseng had a significant loss by air‐drying and had about five times higher content of Rg3 than that of fresh ginseng. This indicates that Rc was transformed into Rg3 during air‐drying. Practical Applications Korean ginseng used as a traditional medicine because of various beneficial effects is thermally processed to improve its efficacy. Ginsenoside is an interesting bioactive compound found in ginseng. Processing methods, air‐drying or steaming, and subsequent air‐drying, changed ginsenosides qualitatively and quantitatively. These results suggest that processing conditions should be carefully employed to enhance or retain the pharmaceutical effects of ginseng products.

Panax ginseng and Panax quinquefolius : From pharmacology to toxicology

“…From a chemical viewpoint, these glycosides are divided into either the 20(S)-protopanaxadiol group (PPD), which includes ginsenosides Rb1, Rb2, Rg3, Rc and Rd or 20(S)-protopanaxatriol (PPT), which comprises ginsenosides Re, Rg1, Rg2 and Rh1, depending on their aglycone moieties (Table 1). In fresh ginseng, ginsenosides Rb1, Rb2, Rc, Re and Rg1 are the main ones (70e80% of total ginsenosides) (Koh et al, 2015). P. ginseng roots often undergo specific processes to promote their preservation and effectiveness, including steaming (red ginseng), air-drying and fermentation (fermented red ginseng) (Koh et al, 2015).…”

“…In fresh ginseng, ginsenosides Rb1, Rb2, Rc, Re and Rg1 are the main ones (70e80% of total ginsenosides) (Koh et al, 2015). P. ginseng roots often undergo specific processes to promote their preservation and effectiveness, including steaming (red ginseng), air-drying and fermentation (fermented red ginseng) (Koh et al, 2015). Both steaming and air-drying reduce the amount of ginsenosides compared to those contained in the fresh root by approximately 50%; nevertheless, the total amount of remaining ginsenosides, after steaming and air-drying, varies between 14 ± 0.04 mg/g and 18 ± 4.5 mg/g (Koh et al, 2015).…”

“…These conservation procedures also alter the quality of ginsenosides, e.g. steaming results in the formation of novel compounds, such as, Rh4 and Rf2, whereas steaming and air-drying significantly increase the amount of Rb1 with respect to fresh ginseng, suggesting that other ginsenosides are transformed into Rb1 during the process (Koh et al, 2015).…”

“…This section outlines the main mechanisms through which ginseng exerts its pleiotropic effects; among ginsenosides, attention has particularly been focused on Rb1 (the most abundant in steamed/air dried P. ginseng and extracts of P. quinquefolius) and compound K (the main active principle formed through the intestinal phase I metabolism of ginseng) (Koh et al, 2015;Wang et al, 1999). However, other ginsenosides, although less abundant, have relevant pharmacological effects as summarized in Table 1.…”

A Continuous Fractionation of Ginsenosides and Polysaccharides FromPanax ginsengUsing Supercritical Carbon Dioxide Technology

“…ginseng contains many components including saponins (ginsenosides), phytosterols, peptides, polysaccharides, fatty acids, polyacetylenes, vitamins and minerals but ginsenosides are the main active ingredients responsible for its pharmacological activities (Yue et al 2007;Chen et al 2008;Koh et al 2015). ginseng contains many components including saponins (ginsenosides), phytosterols, peptides, polysaccharides, fatty acids, polyacetylenes, vitamins and minerals but ginsenosides are the main active ingredients responsible for its pharmacological activities (Yue et al 2007;Chen et al 2008;Koh et al 2015).…”