HPTLC DETERMINATION OF AMINO-ACIDS IN SNAIL-CONDITIONED WATER FROM BIOMPHALARIA-GLABRATA, 2 STRAINS OF HELISOMA-TRIVOLVIS, AND LYMNAEA-ELODES

High performance thin-layer chromatography (HPTLC) was used to analyze amino acids in water conditioned by Biomphalaria glabrata, a Pennsylv ania and Colorado strain of HeEisoma trivolvis, and Lymnaea elodes. Th e snail-conditioned water (SCW) samples were dried with air and recons tituted in 10% n-propanol and then applied to cellulose HPTLC plates a nd developed with n-propanol-water (7:3). Amino acids were detected wi th ninhydrin reagent and the resulting colored sample zones were compa red to known standards. The amino acids present in SCW were identified as alanine, aspartic acid, leucine, phenlalanine, serine, tryptophan, and valine along with one unidentified ninhydrin positive zone. The v aline zone was quantified by densitometric scanning at 610 nm, and the concentrations ranged from 1.3-2.6 mu g mL(-1) snail(-1) in the SCW f or all four strains of snails. There were no significant differences i n the concentrations of valine in water conditioned by the four strain s of snails based on Student's t-test.