BDNF and glioma: The specific objectives of the present study are to: (1) employ an activity-guided fractionation approach to identify compounds in dried commercial sage leaves that upregulate neurotrophin expression in a C6 glioma cell line; (2) determine the chemical structure of the active compound(s); (3) perform a dose -response experiment on the purified active compound; and (4) quantitate the active compound(s) in several greenhouse-grown commercial varieties of culinary sage by means of liquid chromatography mass spectrometry (LC-MS).