Assessment of lectinic activity potentials in extracts of some tropical Euphorbiaceace

Abstract

Lectins bind a variety of cells having cell surface glycoprotein or glycolipid, such as erythrocytes, leukemic cells, yeast and several types of bacteria. Several specificity groups have been identified such as mannose, galactose, N-acetyl glucoseamine, N-acetyl galactoseamine, L-fucose and N-acetyl neuraminic acid. The presence of two or more binding sites for each Lectin molecule allows the agglutination of many cell type. Sixteen (16) species of some tropical Euphorbiaceae plants were assessed for the presence of Lectins. The leaves of Acalypha torta, Acalypha wiskesiana, Acalypha hispida, Codiaeum variegatum, Euphorbia milli, Euphorbia pulcherima, Jatropha curcas and Jatropha gossypifola; the seeds of Croton tiglium, Ricinus comminus and Tetracarpidium conophorum; the stem of Euphorbia tirucalli and the tubers of Manihot esculenta (Cassava, vitamin A variety), Manihot esculenta (cassava, NR 8082 variety), Manihot esculenta (Cassava, TMX 419 variety), Manihot esculenta (Cassava, TMX 4(2) 1425 variety) were used for sourcing the Lectins. A. torta, A. wiskesiana, C. variegatum, C. tiglium, E. milli, E. pulcherima, E. tirucalli, J. curcas, J. gossypifola, R. comminus and T. conophorum agglutinated pooled washed human ABO cells in saline (direct haemagglutination) while A. hispida and the four varieties of M. esculenta showed no agglutination reaction. E. pulcherima showed specificity for B cells only while E. tirucalli showed specificity for O cells only, hence could be rightly indicated by referring to them as anti-B Ep and anti-H Et Lectins respectively (where Ep=Euphorbia pulcherima and Et= Euphorbia tirucalli). However A. torta and T. conophorum cross-reacted with pooled washed ABO cells in differing strengths and when standardized, showed that A. torta at a titre of 16 reacted specifically with O cells and T. conophorum at a titre of 128 reacted specifically with B cells. Based on this, these Lectins could be indicated as anti-H At and anti-B Tc respectively (Where At= Acalypha torta and Tc= Tetracarpidium conophorum). The protein content of the crude extracts of the sixteen (16) species were also assayed using Biuret protein assay method and the results revealed that there are no relation or association between the quantity of protein content and agglutination patterns of the extracts. This research has therefore succeeded in revealing presence of Lectinic properties in extracts of some tropical Euphorbiaceae.