INHIBITORY-ACTION OF SPRAY-DRIED BLOOD-PLASMA AND WHOLE EGG POWDER ONLECTINS IN EXTRACTS OF SEVERAL LEGUME SEEDS - A QUALITATIVE APPROACH

Samples of seeds from eight legume species and Triticum vulgaris grain s were extracted with buffer and lectin activity in the extracts was d etermined in haemagglutination experiments using normal or Pronase-tre ated rabbit erythrocytes. The effect of the addition of spray dried po rcine and bovine plasma powder, whole egg powder, galactosides, whey p owder and specific inhibitors (eg mannose, galactose, N-acetyl galacto samine, fetuin) on haemagglutination activity (HA) was determined. Pla sma powders were potent inhibitors of HA in extracts of Pisum sativum, Vicia faba, Vicia sativa, Lens culinaris and Phaseolus vulgaris. HA i n extracts of Lupinus sp and Phaseolus vulgaris was efficiently decrea sed by whole egg powder, while the lectin of Glycine max could only be inhibited by addition of galactosides, whole and defatted milk powder and whey powder. Inhibitors (plasma and whole egg powder and fetuin) were subjected to SDS-PAGE and Western blotting and blots were incubat ed with biotinylated lectins, except for Lupinus lectin. Results of th e HA experiments were confirmed: lectins which were not influenced by inhibitory compounds in HA experiments also showed no binding with pro teins of the blotted inhibitor. There were strong indications that lec tins were not bound to the albumin fraction of the plasma powders. Res ults are discussed in view of future in vivo experiments. (C) 1998 SCI .