Differentiating Panax ginseng and Panax quinquefolius through SDS-PAGE Analysis

Ginseng is a traditional Chinese herb commonly used in the formulation of tonics. There are 2 main varieties: Oriental (Panax ginseng) and American ginsengs (Panax quinquefolius). Traditional means of authenticating ginseng have become less reliable since they are being processed into various formulations such as tablets, capsules, powder and tea. These products are sometimes also adulterated. This study employed SDS-PAGE as a technique for differentiating between the 2 varieties of ginsengs. Ginseng proteins were separated using a 12% polyacrylamide gel with a three-step electrophoresis: 18 mA for 15 mins, 24 mA for 30 mins and 34 mA for 30 mins. Five bands were identified as potential markers for the ginsengs. Among these, 3 bands at median molecular weights of ~19.47 kDa (interquartile range (IQR) 18.81–20.11 kDa), ~34.42 kDa (IQR 33.75–35.14 kDa) and ~47.35 kDa (IQR 46.16–48.16 kDa) were common to both ginsengs. The band at ~13.23 kDa (IQR 12.78–13.42 kDa) was unique to American ginseng, and the band at ~29.54 (IQR 29.27–29.69 kDa) was unique to Oriental ginseng. This study shows the potential of SDS-PAGE as a proteomic tool in the analysis of ginseng proteins. We hope that these findings can provide an insight to the differences in protein profiles of the 2 ginseng species, and benefit other researchers who are also doing proteomic research on this herb. _____________________________________________________________________________________________________________