Comparison of quality and ginsenoside contents in roots of Panax ginseng at various ages in Gangwon, Korea

Red ginseng made from 6-year-old ginseng ( Panax ginseng C. A. Meyer, Araliaceae) is the representative Korean ginseng product on the worldwide market. Recently, the questions have arisen whether red ginseng can be made from 4- to 5-year-old ginseng, and whether the average content of total ginsenosides is any different than 6-year-old ginseng. The present study was carried out to obtain basic information regarding the quality control standards of P. ginseng cultivated in Gangwon, Korea, a newly emerging area of ginseng production. 80 samples from 45 farms in 9 counties of the Gangwon province, were collected according to age (4-, 5-, and 6-year-old) and cultivation conditions, in order to compare the quality of ginseng. Identification of the root age of ginseng was performed using a new technique [1] of histochemical staining of secretory duct layers (SDL). Total Ginsenoside-Rb 1 , -Rb 2 , -Rc, -Rd, -Re, -Rf, -Rg 1 , -Rg 2 , -Rg 3 , -Rh 1 -Rh 2 and R 1 , the effective components of Korean ginseng, were detected by HPLC analysis [2]. Acidic polysaccharide, crude polyacetylene, polyphenol and flavonoid were analyzed by using method of spectrophotometric determination [3], while the crude protein was analyzed by using Lowry method [4]. Extract and crude saponin [5] increased gradually over 6 years. 6-year-old fresh ginseng had the highest average content of total saponins and protein. The mean ± S.D. values of the total saponin content of 4-, 5- and 6-year-old ginseng -were 26.9 ± 1.17, 29.6 ± 1.66, and 32.0 ± 2.27 mg/g, respectively. The level of other non-saponins (such as acidic polysaccharides, total polyphenols and flavonoids [5]) in 6-year-old ginseng roots was also higher than those cultivated for shorter periods. Therefore, it can be concluded that the highest quality of ginseng grown in Ganwon can be obtained from 6-year-old ginseng roots in which the content of active ingredients is remarkably increased. Fig. 1: A fresh section of a 6-year-old root stained with 1% nile blue (left panel). The external features of 4- to 6-year-old roots of ginseng (right panel) (SDL: The number of secretory duct layers, the identification of the actual growth age of ginseng roots using the histochemical staining method). Fig. 2: Comparison of the total saponin and protein content of 4- to 6-year-old ginseng cultivated in Gangwon, Korea. Acknowledgements: This work is supported by RDA national funds (Republic of Korea) under the project PJ0109432016.