Biological importance of gamma-glutamyl-S-methylcysteine of kidney bean (Phaseolus vulgaris L.)

The effects of S-methyl-L-cysteine (SMC) on growth and food intake by rats were investigated and in vivo absorption studies of gamma-glutamyl-S-methyl -L-cysteine and free SMC were performed. The results showed that the peptid e is slowly absorbed and only free SMC could be detected in the blood. The diets (10% casein), containing SMC, depressed food intake and animals' grow th. Both effects were proportional to the SMC contents in the diets. The re sults obtained with pair-fed groups led to the conclusion that the depressi on in growth was caused by the refusal of the SMC diets. The addition of cy stine to the SMC diet only partially restored normal growth. Histological e xamination of livers, kidneys and spleens of rats fed with SMC showed no ti ssue alterations, except for a significant increase in the kidney weights. The hematological features did not show any significant differences, but th ere was a slight increase in erythroid precursors and young forms in the bo ne marrow, which might indicate an increased erythrocyte turnover. These re sults suggest that the reduction in food intake could be associated with so me defence mechanism against toxic substances. (C) 2001 Elsevier Science Lt d. All rights reserved.