METHOD FOR QUANTIFYING SULFORAPHANE BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY IN CRUCIFEROUS PLANTS

摘要

Sulforaphane is an isothiocyanate having anti-microbial and anti-carcinogenic properties, found in a broad range of vegetables of the Brassica oleracea genus, of which broccoli and cabbage are considered to be the most important types. The present invention describes a method for extracting, identifying and quantifying sulforaphane in the edible parts of broccoli and in cabbage leaves by high-performance liquid chromatography (HPLC). The preparation of the sample for sulforaphane quantification includes: conversion of glucoraphanin to sulforaphane (45 ± 2 ºC for 2.5 h), extraction with dichloromethane, purification of the extract in solid-phase extraction columns, and detection by HPLC-UV. In broccoli, the concentration of sulforaphane ranges from 196 μg/g bs (whole head) to 499 μg/g bs (inflorescences). Red cabbage (101.99 μg/g bs) had higher sulforaphane content than green cabbage (7.58 μg/g bs). The method showed that the inflorescences of broccoli and the leaves of red cabbage are rich in sulforaphane.