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Apple snail is one of the major pest of rice crop and saponin proved to be the most promising bioactive compound to control it. This study was carried out to quantify saponin from God's Crown, Phaleria macrocarpa and to evaluate its efficacy against the biological activities of black apple snail, Pomacea maculata. Fruits, leaves and stem-barks of P. macrocarpa were quantified for saponin using HPLC. The toxicity of leaf and fruit crude extracts was evaluated through mortality and feeding deterrent bioassays using complete randomized design and data were analyzed by ANOVA for LSD test. The highest saponin contents 24.67 ppm was detected in fruits followed by 22.67 ppm in leaves and 5.94 ppm in stembark. Bioassays showed the highest mortality percentage (44%) after 24 hours exposure at the concentration of 1000 ppm of a leaf extract followed by 36% and 28% @ 750 and 1000 ppm of leaf and fruit extracts, respectively. After the exposure of 48 hours, mortality percentage increased to 100% @ 1000 and 750 ppm of both crude extracts while the mortality percentage recorded at the concentration of 500 ppm of leaves and fruits were 56% and 52% respectively. Mortality percentage at the concentration of 500 ppm was increased to 80% and 68% in leaf and fruit extracts after exposure of 72 hours, respectively. In terms of feeding deterrent, 1000, 750 and 500 ppm concentration of both crude extracts were not significantly different from the positive control niclosamide (p>0.05). The results obtained from the study revealed that saponin extracted from fruits and leaves of P. macrocarpa has a potential to control black apple snails. [ABSTRACT FROM AUTHOR]

Despite the great benefits of using synthetic molluscicides as mollusc control agents, they can destroy the entire ecosystems, causing detrimental effects on human health and non-target organisms. Essential oils and/or their constituents are gaining increasing interest for using as safe alternatives to pesticides for controlling various pests including gastropods. The present review was conceived to overview on essential oils and/or their components as novel mollusc control agents that can be used in sustainable agriculture and medical public health sectors. We also intended to find approaches for new essential oils based on pesticidal products as a promising alternative for mollusc control. Indeed, this review covers their molluscicidal, antifeedant and repellent properties and discusses their structure–activity relationships. Phytochemical analysis of aromatic plants using GC and GC–MS to elucidate the possible secondary metabolites present which could be responsible for their molluscicidal efficacy and to know of their mechanism of action is also addressed. Furthermore, the performance of component blends explored and efforts evolved for maximizing the molluscicidal activity of essential oil components by either synthesized new derivatives or mixing with synergists are also discussed. We also looked at additional assessment of various issues before adopting these products as general molluscicides. All the data in this review supported the promising uses of essential oils and/or their components in harmful gastropod pest control. [ABSTRACT FROM AUTHOR]