Submitted to: Industrial Crops and Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/11/2005
Publication Date: 7/1/2006
Citation: Bedir, E., Tellez, M., Lata, H., Khan, I., Cushman, K.E., Moraes, R.M. 2006. Post-harvest and scale-up extraction of american mayapple leaves for podophyllotoxin production. Industrial Crops and Products. 24(1): 3-7. Interpretive Summary: Podophyllotoxin is a natural product used in the manufacture of two anticancer pharmaceuticals. It is found in the leaves of mayapple, for which we have a patent for a high yield extraction process. This paper describes the further development of this method for handling large samples of dried mayapple leaves.
Technical Abstract: Leaves of American mayapple, Podophyllum peltatum, are of interest to the pharmaceutical industry as an alternative source of podophyllotoxin. In this study, the effects of post-harvest handling were evaluated by inflicting physical damage to leaves of mayapple to simulate rough handling. The effects of storage conditions before and after being dried were also evaluated. In addition, techniques for conducting large-scale extractions of podophyllotoxin from bulk samples were investigated. Crushing injury drastically improved podophyllotoxin content of leaves when dried at 40 ºC within 24 h of harvest. In contrast, podophyllotoxin content was greatly reduced when dried at room temperature at 15% relative humidity and 24 ºC. Podophyllotoxin content was stable, with no significant changes over time, when leaves were dried, ground, and stored under different conditions for up to 60 days. Based on these findings, we can state that mayapple leaves need not be handled carefully at harvest. In fact, leaves can be handled in a manner consistent with mechanical injury as long as leaves are dried at 40 ºC within 24 h. Leaves can then be stored for up to 60 days, and probably much longer, when dry. If leaves cannot be dried in a timely manner, leaves can be stored at 4 ºC for up to four weeks without significant loss of podophyllotoxin content. Our results also indicate that large-scale extractions of bulk samples are possible. Procedures that proved successful, as well as those that did not, are discussed.