The Molluscicidal Effects on Golden Apple Snail and Toxic Effects on Nile Tilapia (Oreochromis niloticus) from the Soapberry (Sapindus rarak) Pericarp Crude Extract

Abstract

The golden apple snail (Pomacea canaliculata Lamarck) is an invasive species that causes ecological damage, agricultural losses and public health concerns. It act as an intermediate host of the parasite Angiostrongilus cantonensis. Traditional eradication methods, such as physical and biological control, are often difficult to implement effectively. As a result, most farmers prefer to use chemical methods due to their high effectiveness. However, these methods can have negative impacts on both the environment and human health. Therefore, the use of herbal extracts with molluscicidal properties that are environmentally friendly and safe for human health, is a promising alternative for controlling this snail. The molluscicidal activity from the soapberry (Sapindus rarak) pericarp crude extract has been reported, but its toxic effects on other aquatic organisms have not been thoroughly investigated. This research aims to study: 1) the molluscicidal effect of the soapberry pericarp crude extract on the golden apple snails, 2) its bioactive compounds, and 3) its toxic effects on Nile tilapias (Oreochromis niloticus). The results showed that at the concentrations of 25 ppm and 50 ppm of soapberry pericarp crude extract caused 50% mortality in snails within 24 hours and 90% within 72 hours, respectively. However, this concentration caused 100% mortality in Nile tilapias within 48 hours. Hederagenin was the bioactive compound found at 0.44%. It is a glycoside saponin with hemolytic properties on organisms. Hence, it might be the cause of snail and Nile tilapia mortality in this study. Our findings recommended that farmers should avoid using soapberry crude extract to eliminate the golden apple snails in the rice fields, lotus ponds, fish ponds, shrimp ponds, or other aquatic animal nurseries, as it is toxic to aquatic animals.