A new method for determining concentrations of Endod‐S (Phytolacca dodecandra) in water during mollusciciding

Abstract A hemolytic method was developed for the quantitative determination of oleanane saponin (Endod‐S) in Phvtolacca 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/1. The TLC method gave a correlation coefficient of 0.99 for saponin levels above 1.5 μq. 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/1. Similarly, sample size limited TLC quantitation of these saponins at levels below 1 μg. Both the TLC and the hemolysis methods on identical Endod‐S water samples gave comparable results at saponin levels between 2 and 6 mg/1. A snail bioassay showed that the LC50 and the LC90 con...