For the cytochemical characterization of the storage material present in guandu, lab-lab and mucuna, seeds of each species were fixed and prepared for microscopy. Routine and specific fixation methods for proteins, lipids, neutral and acidic polysaccharides were used. The main reserves of the seeds were also analyzed and characterized. The results showed that starch is the principal reserve, with proteins surrounding the starch grains, as well as a few lipid globules. The starch concentration was 55% of the dry weight (DW) for guandu, 53% for lab-lab and 40% for mucuna. The proteins were more abundant in lab-lab, with 26% DW, while guandu and mucuna had respectively 19% and 17%. Lipids represented up to 2% of the total DW of the three species with mucuna presenting the largest quantity. The analyses of neutral saccharides showed a large amount of glucose due to the starch reserve, but also appreciable quantities of galactose and arabinose, which always occurred in greater quantities in mucuna. Electrophoretic patterns for proteins of guandu and lab-lab were quite similar, suggesting a a phylogenetic proximity between these species. The principal proteins had a molecular relative mass between 65 to 70 kg/mol.
leguminous; seeds; Cajanus cajan; Lab-lab purpureum; Mucuna aterrima; storage