**4. Conclusions**

Pu ffing changed the structure of ginseng from dense to porous leading to easy elution of bioactive compounds from ginseng. This phenomenon increased the extraction yields and crude saponin content of both pu ffed American and Canadian ginsengs. It is notable that the levels of the major ginsenosides (Rb1, Rb2, Rc, Rd, Re) increased by pu ffing at 686 kPa, possibly as a result of the formation of a porous structure without thermal conversion of the ginsenosides. Deglycosylation and pyrolysis of major ginsenosides during the pu ffing process induced the production and increase of minor ginsenosides (Rg2, Rg3, Compound K, and Rh2). Especially, the level of compound K dramatically increased by pu ffing at 980 kPa in both American and Canadian ginsengs. Moreover, pu ffing greatly increased antioxidant activities (ABTS and DPPH), and the increase of MRPs level seemed to significantly a ffect the ABTS of pu ffed ginsengs. Pu ffed American and Canadian ginsengs showed higher antioxidant activities and higher minor ginsenoside levels than non-pu ffed ginsengs, a trend similar to that of pu ffed *P. ginseng*. There was no significant di fference between American and Canadian ginsengs in either control or pu ffed samples. In the case of *P. ginseng,* red ginseng, and black ginseng, the preparation takes a very long time, which is not economical. On the other hand, the preparation of pu ffed ginseng takes relatively a very short time, and more e ffective changes in ginsenosides and bioactive compounds can be obtained. Therefore, pu ffing is an e fficient and economic processing method appropriate for both American and Canadian ginsengs to enhance ginseng's antioxidant activity and produce minor ginsenosides, such as Rg3, Compound K, and Rh2.

**Author Contributions:** Conceptualization, H.L., W.K., and M.-Y.B.; funding acquisition, H.L., W.K., and M.-Y.B.; investigation, M.-S.K., S.-J.J., W.K., and M.-Y.B.; methodology, M.-S.K., S.-J.J., S.J.Y., Y.-J.P., D.-O.K., and B.-Y.K.; project administration, H.L., W.K., and M.-Y.B.; supervision, W.K., and M.-Y.B.; writing—original draft, M.-S.K., S.-J.J., W.K., and M.-Y.B.; writing—review and editing, H.L., Y.-J.P., D.-O.K., B.-Y.K., W.K., and M.-Y.B.

**Funding:** This work was supported by the Rural Development Administration, Republic of Korea (PJ01314402). **Conflicts of Interest:** The authors declare no conflicts of interest.
