Pomacea canaliculata, one of the 100 most destructive invasive species in the world, and it is an important intermediate host of Angiostrongylus cantonensis. The molluscicides in current use are an effective method for controlling snails. However, most molluscicides have no slow-release effect and are toxic to nontarget organisms. Thus, these molluscicides cannot be used on a large scale to effectively act on snails. In this study, gelatin, a safe and nontoxic substance, was combined with sustained-release molluscicide and was found to reduce the toxicity of niclosamide to nontarget organisms. We assessed the effects of gelatin and molluscicide in controlling P. canaliculata snails and eggs. The results demonstrated that the niclosamide retention time with 1.0% and 1.5% gelatin sustained-release agents reached 20 days. Additionally, the mortality rate of P. canaliculata and their eggs increased as the concentration of the niclosamide sustained-release agents increased. The adult mortality rate of P. canaliculata reached 50% after the snails were exposed to gelatin with 0.1 mg/L niclosamide for 48 h. The hatching rate of P. canaliculata was only 28.5% of the normal group after the treatment was applied. The sustained-release molluscicide at this concentration was less toxic to zebrafish, which means that this molluscicide can increase the safety of niclosamide to control P. canaliculata in aquatic environments. In this study, we explored the safety of using niclosamide sustained-release agents with gelatin against P. canaliculata. The results suggest that gelatin is an ideal sustained-release agent that can provide a foundation for subsequent improvements in control of P. canaliculata.

Background: The golden apple snail (Pomacea canaliculata), an invasive species originating from South America, has inflicted considerable agricultural and ecological harm in non-native habitats. While the molluscicide niclosamide is currently effective against P. canaliculata, its prolonged use raises environmental concerns and the risk of resistance development. Results: BAM 15 possesses strong molluscicidal activity against P. canaliculata, with 72 h LC₅₀ values of 0.4564 mg/L for adults (shell height: 20–25 mm), 0.3352 mg/L for subadults (10–15 mm), and 0.1142 mg/L for juveniles (2–3 mm). Metabolomic and proteomic profiling revealed that the altered metabolites and proteins both converged on energy metabolism and oxidative stress. Experimental validation revealed that BAM15 collapsed the mitochondrial membrane potential, drove MDA and H₂O₂ upward while depleting NADPH, boosted CAT, SOD and GPX activities, yet suppressed GR, and ultimately inflicted overt damage in the head-foot tissue of P. canaliculata. Conclusions: Our findings reveal that BAM 15 operates via a three-stage mechanism: (1) it disrupts membrane potential (ΔΨm) and impairs ATP production, severely disturbing energy metabolism; (2) energy deficits stimulate excessive electron transport chain activity, generating reactive oxygen species (ROS) and initiating oxidative stress; (3) persistent metabolic imbalance and oxidative damage culminate in extensive tissue injury. These results identify BAM 15 as a promising candidate for molluscicide development.

The snail, Oncomelania hupensis , is the only intermediate host of Schistosoma japonicum . Thus, snail control is one of the most rapid and effective strategies for disrupting schistosomiasis transmission. In this study, 125 botanical extracts were screened for molluscicidal activity, leading to the selection of the extract of Helleborus thibetanus (EHT) for further evaluation. EHT exhibited strong molluscicidal activity against O. hupensis (LC ₅₀ value of 12.54 mg/L and LD ₅₀ value of 1.400 g/m ² ). In field trials, an EHT dose of 10 g/m ² killed 85.19% of the snails. Histopathological evaluation revealed that EHT caused comprehensive damage to the cephalopodium, gill, salivary gland, stomach, and hepatopancreas. Importantly, EHT was also generally safe for non-target organisms, such as Danio rerio , Daphnia magna , Pelophylax nigromaculatus , Cipangopaludina chinensis , and Neocaridina denticulata at the test concentration. These results suggest the potential of EHT as an effective and eco-friendly molluscicide for the control of O. hupensis .