ABSTRACT: A student activity that focuses on the isolation of glucoraphanin
from broccoli using preparative high-performance liquid chromatography
(HPLC) is presented here. Glucoraphanin is a glucosinolate, whose byproducts
are known to possess anticancer properties. It is present naturally at high levels
in broccoli and other Brassica vegetables. This activity has students practicing
and developing a number of skills including liquid extraction; cleanup by solidphase
extraction; analytical HPLC with diode array detection to identify the
peak of interest; and preparative HPLC coupled with a fraction collector to
isolate the glucoraphanin fraction. It also represents an authentic application of
preparative HPLC as glucoraphanin is not readily available from the main
chemical suppliers.