Canavanine analysis of alfalfa extracts by high performance liquid chromatography using pre-column derivatization.

The purpose of this project was to isolate and quantitate canavanine in three different alfalfa samples because it has been hypothesized that alfalfa and therefore canavanine ingestion may exacerbate systemic lupus erythematosus (SLE) in humans. Ten alfalfa tablets were ground into a fine powder, and 100 mg was extracted for canavanine. The extracted canavanine was derivatized prior to quantitation by high performance liquid chromatography. The canavanine content of alfalfa tablets averaged 25.3 and 33.8 micrograms/g depending on lot number and extraction method. Because ten alfalfa tablets are recommended daily, this would provide approximately 0.18 mg of canavanine. Whether daily ingestion of canavanine exacerbated SLE in two patients consuming 15 and 8 alfalfa tablets (0.27 and 0.15 mg, respectively) is uncertain and warrants further investigation.