A hemolytic method was developed for the quantitative determination of
oleanane saponin (
Endod-S) in Phytolacca dodecandra (Phytolaccaceae), a plant with potent molluscicidal properties. A chemical method based on thin-layer chromatography (TLC) was used as a control for comparison with a
hemolysis test. Standard curves for calibration of both tests of
Endod-S gave high correlation coefficients. The
hemolysis method gave a correlation coefficient of 0.98 for
saponin (
Endod-S) levels ranging from 1.6 to 4.2 mg/l. The TLC method gave a correlation coefficient of 0.99 for
saponin levels above 1.5 micrograms. Due to the action of
saponins on erythrocytes, the
hemolysis method could not be used at levels below 1.6 and above 4.2 mg/l. Similarly, sample size limited TLC quantitation of these
saponins at levels below 1 microgram. Both the TLC and the
hemolysis methods on identical
Endod-S water samples gave comparable results at
saponin levels between 2 and 6 mg/l. A snail bioassay showed that the LC50 and the LC90 concentrations of
Endod-S to the snail Biomphalaria glabrata (albino) were 2.57 and 2.92 mg/l respectively. These values fell in the standard curve range for the
hemolysis method thus indicating that the
hemolysis method is of practical value for testing
Endod-S concentrations that would actually be used in field applications for snail control. The
hemolysis method is less expensive than TLC and can be easily adapted to field conditions.