Evaluation of illicium verum (star anise) against Biomphalaria alexandrina Snails and their Infection with Schistosoma mansoni

Schistosomiasis, the second most common parasitic disease worldwide, is caused by trematodes of the Schistosoma genus. One of the most promising methods for controlling schistosomiasis in Egypt is the use of plant-based molluscicides to target snails. The application of plant-origin molluscicides offers several benefits, including being safe, inexpensive, and environmentally friendly. The purpose of this study was to evaluate the molluscicidal and larvicidal effects of Illicium verum (star anise) on the free larval stages of the Schistosoma mansoni parasite and its intermediate host. Additionally, the study assessed various biological, biochemical, and histological characteristics of Biomphalaria alexandrina snails treated with I. verum. The most promising variety of I. verum was identified, and B. alexandrina snails were infected with S. mansoni. Hemocyte counts, antioxidant enzyme activities, and histological reactions of the snails were analyzed. The cold-dried powder of I. verum fruit, suspended in water, demonstrated molluscicidal effects on B. alexandrina snails and larvicidal effects on the cercariae and miracidia of S. mansoni. The survival rate of S. mansoni-infected snails exposed to sublethal concentrations of star anise at the time of first cercarial shedding was significantly lower compared to the control group (P< 0.05). Furthermore, infection rates and cercarial production in infected snails were significantly reduced. Antioxidant enzymes, such as superoxide dismutase (SOD), showed a notable increase after the snails were exposed to a sub-lethal concentration (LC25) of I. verum (36.60 for the treatment group compared to 5.43 for the control group). The use of a fruit dry powder water suspension of Illicium verum proved to be effective in snail management. This treatment interferes with snail biology and infection with S. mansoni, potentially halting and limiting the spread of the parasite.