Dataset Information

Molluscicidal effectiveness of Luo-Wei, a novel plant-derived molluscicide, against Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus.

ABSTRACT:

Background

Control of snail intermediate hosts has been proved to be a fast and efficient approach for interrupting the transmission of schistosomiasis. Some plant extracts have shown obvious molluscicidal activity, and a new compound Luo-Wei, also named tea-seed distilled saponin (TDS), was developed based on the saponins extracted from Camellia oleifera seeds. We aimed to test the molluscicidal activity of 4% TDS against the intermediate host snails in China and Egypt, and evaluate its environmental safety to non-target organisms.

Methods

In the laboratory, Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus were exposed to 4% TDS, and the median lethal concentration (LC₅₀) was estimated at 24, 48 and 72 h. In the field, snail mortalities were assessed 1, 2, 3 and 7 d post-immersion with 2.5 g/m³ 4% TDS and 1, 3, 7 and 15 d post-spraying with 5 g/m² 4% TDS. In addition, the acute toxicity of 4% TDS to Japanese quail (Coturnix japonica), zebrafish (Brachydanio rerio) and freshwater shrimp (Macrobrachium nipponense) was assessed by estimations of LC₅₀ or median lethal dose (LD₅₀).

Results

In the laboratory, the LC₅₀ values of 4% TDS for O. hupensis were 0.701, 0.371 and 0.33 mg/L at 24, 48 and 72 h, respectively, and 4% TDS showed a 1.975 mg/L [corrected] 24 h LC₅₀ against B. alexandrina, and a 1.396 mg/L 24 h LC₅₀ against B. truncatus. Across all study regions, the pooled mortalities of O. hupensis were 72, 86, 94 and 98% at 1, 2, 3 and 7 d, following field immersion of 4% TDS at a dose of 2.5 g/m³, and were 69, 77, 85 and 88% at 1, 3, 7 and 15 d, following field spraying at 5 g/m², respectively. 4% TDS had moderate toxicity to Japanese quail (7 d LD₅₀ > 60 mg/kg) and to shrimp (96 h LC₅₀ = 6.28 mg/L; 95% CI: 3.53-11.2 mg/L), whereas its toxicity to zebrafish was high (96 h LC₅₀ = 0.15 mg/L; 95% CI: 0.14-0.17 mg/L).

Conclusions

4% TDS is active against O. hupensis, B. alexandrina and B. truncatus under laboratory and field conditions, and it may be a candidate molluscicide of plant origin.

SUBMITTER: Jia TW

PROVIDER: S-EPMC6480903 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Publications

Molluscicidal effectiveness of Luo-Wei, a novel plant-derived molluscicide, against Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus.

Jia Tie-Wu TW Wang Wei W Sun Le-Ping LP Lv Shan S Yang Kun K Zhang Neng-Min NM Huang Xi-Bao XB Liu Jian-Bing JB Liu Han-Cheng HC Liu Rui-Hua RH Gawish Fathia A FA Habib Mohamed R MR El-Emam Mohamed A MA King Charles H CH Zhou Xiao-Nong XN

Infectious diseases of poverty 20190331 1

<h4>Background</h4>Control of snail intermediate hosts has been proved to be a fast and efficient approach for interrupting the transmission of schistosomiasis. Some plant extracts have shown obvious molluscicidal activity, and a new compound Luo-Wei, also named tea-seed distilled saponin (TDS), was developed based on the saponins extracted from Camellia oleifera seeds. We aimed to test the molluscicidal activity of 4% TDS against the intermediate host snails in China and Egypt, and evaluate its ...[more]

PMID: 31014390

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Dataset Information

Molluscicidal effectiveness of Luo-Wei, a novel plant-derived molluscicide, against Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus.

Background

Methods

Results

Conclusions

Publications

Molluscicidal effectiveness of Luo-Wei, a novel plant-derived molluscicide, against Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus.

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