Phytate content was determined by extraction with 24% HCl, filtered, and its absorbance was then measured at 520nm. Tannin content was determined by maceration with methanol, filtration, and absorbance measurement at 720nm. Oxalate content was determined by extraction with 30% HCl, filtrated, and then titrated with 0.1M KMnO4. Saponin content was determined using the method described by , which involved extraction of the samples with 20% ethanol, purification with diethyl ether and n-butanol, and evaporation to dryness