Lantana camara Essential Oils from Vietnam: Chemical Composition, Molluscicidal, and Mosquito Larvicidal Activity.

Lantana camara is a troublesome invasive plant introduced to many tropical regions, including Southeast Asia. However, the plant does hold promise as a source of essential oils that may be explored for potential use. Fresh water snails such as Pomacea canaliculata, Gyraulus convexiusculus, and Tarebia granifera can be problematic agricultural pests as well as hosts for parasitic worms. Aedes and Culex mosquitoes are notorious vectors of numerous viral pathogens. Control of these vectors is of utmost importance. In this work, the essential oil compositions, molluscicidal, and mosquito larvicidal activities of four collections of L. camara from north-central Vietnam have been investigated. The sesquiterpene-rich L. camara essential oils showed wide variation in their compositions, not only compared to essential oils from other geographical locations (at least six possible chemotypes), but also between the four samples from Vietnam. L. camara essential oils showed molluscicidal activities comparable to the positive control, tea saponin, as well as other botanical agents. The median lethal concentrations (LC50 ) against the snails were 23.6-40.2 µg/mL (P. canaliculata), 7.9-29.6 µg/mL (G. convexiusculus), and 15.0-29.6 µg/mL (T. granifera). The essential oils showed good mosquito larvicidal activities with 24-h LC50 values of 15.1-29.0 µg/mL, 26.4-53.8 µg/mL, and 20.8-59.3 µg/mL against Ae. aegypti, Ae. albopictus, and Cx. quinquefasciatus, respectively. The essential oils were more toxic to snails and mosquito larvae than they were to the non-target water bug, Diplonychus rusticus (24-h LC50 =103.7-162.5 µg/mL). Sesquiterpene components of the essential oils may be acting as acetylcholinesterase (AChE) inhibitors. These results suggest that the invasive plant, L. camara, may be a renewable botanical pesticidal agent.

Evaluation of molluscicidal activity of three mangrove species (Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle) and their effects on the bioactivity of Biomphalaria glabrata Say, 1818.

Schistosomiasis is a disease of global extent reaching populations in social vulnerability. One of the control measures of this parasitosis is the use of molluscicidal substances that can fight snails of the genus Biomphalaria, intermediate hosts of Schistosoma mansoni. The aim of this work was to study the toxic activity of three mangrove species (Avicennia schaueriana Stapf. & Leech, ex Moldenke, 1939, Laguncularia racemosa (L.) CF Gaertn, 1807 and Rhizophora mangle L. 1753) on the biological activities of snails Biomphalaria glabrata. Hydroalcoholic extracts were prepared from the stem and leaves of each of the three plant species to which mollusks were exposed. The phytochemical analysis of plants showed the presence of important metabolites in the leaves and stems of L. racemosa and R. mangle, such as tannins and saponins, but the absence of these metabolites in A. schaueriana. Leaf and stem extracts of the three plant species showed low molluscicidal activity, not reaching the standards determined by the World Health Organization (WHO, 1983). L. racemosa and R. mangle has interfered with motility, feeding and oviposition of snails, unlike the extracts of A. schaueriana, which had no effect on these activities.

Impact of Moringa oleifera seed aqueous extract on some biological, biochemical, and histological aspects of Biomphalaria alexandrina snails.

Schistosomiasis is one of the neglected tropical diseases. It is a snail-borne trematode infection, and Biomphalaria alexandrina snails are the intermediate host of Schistosoma mansoni in Egypt. The objective of this study is to evaluate the molluscicidal activity of the aqueous seed extract of Moringa oleifera against B. alexandrina snails. The results showed that this aqueous extract was lethal for B. alexandrina snails (LC50 0.27 g/l; LC90 0.41 g/l). Exposure of snails to the sublethal concentrations of this aqueous extract caused a considerable reduction in survival rates and hatchability rates of eggs of these snails. Moreover, it negatively affected some biochemical aspects, where it increased the levels of transaminases (ALT and AST), while it decreased the concentrations of total protein, albumin, and globulin concentration. Histological examinations of the digestive gland of snails exposed to the sublethal concentrations of aqueous seed extract of M. oleifera revealed severe damage in the digestive cells, where they lost their tips and some were degenerated, while the secretory cells increased in number. Regarding the hermaphrodite gland, there were losses of connective tissues and irregular sperms, and the eggs were degenerated. These findings prove the potent activity of aqueous seed extract of M. oleifera against the intermediate hosts of Schistosoma mansoni and provide a considerable scope in exploiting local indigenous resources for snails' molluscicidal agents.

Molluscicidal activity of Solanum elaeagnifolium seeds against Galba truncatula intermediate host of Fasciola hepatica: Identification of ß-solamarine.

CONTEXT: The persistence of fascioliasis in many developing countries urges the search for simple, cheap, and effective substances. In this view, plants provide interesting molluscicidal activities thanks to the secondary metabolites they produce. The genus Solanum is known for its potent effect on vector snails. OBJECTIVE: The molluscicidal activity of Solanum elaeagnifolium Cav. (Solanaceae) seeds against Galba truncatula Müll. (Lymnaeidae), intermediate host of Fasciola hepatica L. (Fasciolidae), was evaluated. MATERIALS AND METHODS: Solanum elaeagnifolium seeds were powdered and successively extracted using n-hexane, methylene chloride, acetone, and methanol, for 20 h each. After filtration, solvents were evaporated. An acid-base treatment was conducted on seed methanolic extract to isolate total alkaloids and ß-solamarine. Total saponins fraction was obtained after successive macerations and evaporations. The molluscicidal activity was evaluated by subjecting snails, in groups of 10, for 48 h to 500 mL of extracts, fractions, and pure product aqueous solutions, each containing amounts, ranging from 1 to 50 mg of plant material in 5 mg increments. RESULTS: The methanolic extract of seeds, ß-solamarine isolated for the first time from this plant and total saponins fraction showed very potent activities on snails, giving respective median lethal concentrations (LC50) of 1.18, 0.49, and 0.94 mg/L. Total alkaloids fraction obtained from the methanolic extract was less active giving an LC50 value of 14.67 mg/L. DISCUSSION AND CONCLUSION: This study emphasizes that glycoalkaloids and saponins of Solanum elaeagnifolium are potent molluscicidal agents. Seed methanolic extract, ß-solamarine, and total saponins fraction may be used as molluscicides.

Anti-infective Natural Products from Cyanobacteria.

Cyanobacteria are a promising yet underexplored source for novel natural products with potent biological activities. While predominantly cytotoxic compounds have been isolated from cyanobacteria in the past, there are also a significant number of compounds known that possess anti-infective activities. As the need for novel anti-infective lead compounds is high, this manuscript aims at giving a concise overview on the current knowledge about anti-infective secondary metabolites isolated from cyanobacteria. Antibacterial, antifungal, antiviral, antiprotozoal, and molluscicidal activities are discussed. Covering up to February 2015.

Acacetin-7-rutinoside from Buddleja lindleyana, a new molluscicidal agent against Oncomelania hupensis.

Buddleja lindleyana is a medicinally important member of the family Loganiaceae distributed in Eastern China. The plant has been used in different traditional medications for the treatment of various diseases. Acacetin-7-rutinoside was isolated from the n-butanol fraction of fresh B. lindleyana leaves and found to be a new molluscicidal agent against the snail Oncomelania hupensis. The structure of acacetin-7-rutinoside was elucidated based on spectral data, including 1H NMR and 13C NMR.

A penta-substituted pyridine alkaloid from the rhizome of Jatropha elliptica (Pohl) Muell. Arg. is active against Schistosoma mansoni and Biomphalaria glabrata.

Jatropha elliptica is a shrub distributed throughout the north and west of Brazil and reputedly possesses a wide range of therapeutical properties. The roots of this plant possess molluscicidal activity and contain terpenoids, coumarin, lignoid, steroids and alkaloid. In the present study, we assessed the schistosomicidal, miracicidal and cercaricidal activities (against Schistosoma mansoni) and molluscicidal activities (against adults and egg masses of Biomphalaria glabrata) of the alkaloid diethyl 4-phenyl-2,6-dimethyl-3,5-pyridinedicarboxylate, isolated from the ethanol extract of the rhizome of J. elliptica, have been determined. The alkaloid was 100% lethal to adult schistosomes within 4 days at a concentration of 50 µg/mL. Alterations were observed in the schistosome tegument occasioned by treatment with the alkaloid, such as formation of vesicles and vacuolisation. The extent of tegumental damage of the worm was proportional to the time of incubation and to the concentration of compound. The alkaloid also exhibited a potent cercaricidal activity (LC100 = 2 µg/mL); it was totally ineffective against miracicidal forms of the parasite. Moreover, the alkaloid presented strong activity against adult snails (LC90 = 36.43 µg/mL) but was inactive against their egg masses. It is observed then the potential of this compound for the development of new therapies for the treatment of schistosomiasis.

OVICIDAL EFFECT OF PIPERACEAE SPECIES ON Biomphalaria glabrata, Schistosoma mansoni HOST / Efeito ovicida de espécies de Piperaceae em Biomphalaria glabrata, hospedeiro do Schistosoma mansoni

SUMMARY Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage. The extracts were evaluated in concentrations ranging from 100 to 10 mg/L. Piper crassinervium and Piper tuberculatum extracts were the most active (100% of mortality at 20 mg/L and 30 mg/L respectively). .

RESUMO A esquistossomose é uma doença negligenciada de importância para a saúde pública em regiões tropicais e subtropicais. Uma alternativa para o controle da doença é o uso de moluscicidas para eliminar ou reduzir a população de caramujo hospedeiro, acarretando uma redução da transmissão da doença nas regiões endemicas. Neste estudo, nove extratos vegetais provenientes de oito espécies de Piperaceae foram expostos a embriões de Biomphalaria glabrata no estágio de blástula. Os extratos foram avaliados em concentrações que variaram entre 100 e 10 mg/L, sendo Piper crassinervium e Piper tuberculatum os extratos mais ativos (100% de mortalidade a 20 mg/L e 30 mg/L respectivamente). .

Ovicidal effect of Piperaceae species on Biomphalaria glabrata, Schistosoma mansoni host.

Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage. The extracts were evaluated in concentrations ranging from 100 to 10 mg/L. Piper crassinervium and Piper tuberculatum extracts were the most active (100% of mortality at 20 mg/L and 30 mg/L respectively).

[Mollusicidal effects of some species of plants in hilly and mountainous areas].

OBJECTIVE: To valuate the mollusicidal effects of some plants cultivated in the hilly and mountainous areas on Oncomelania hupensis and screen the plants against O. hupensis snails. METHODS: The mollusicidal effects of water extracts of plant materials were tested in laboratory. RESULT: The LC50 of all the species in 24 h, 48 h, and 120 h reached the middle noxious level against O. hupensis snails. According to the taxis of LC50(s) in 120 h, Eucalyptus camaldulensis was best with a LC50 of 0.013%, and Ailanthus altissima, Zanthoxylum bungeanum, Juglans regia, Melia azedarach, Nerium indicum, Pterocarva stenobtera, Cinnamomum camphora, Vetiveria zizanioides, and Citrus reticulata were the second with LC50 (s) between 0.020% and 0.370%, and Zingiber officinale had a lower effect on snail control with a LC50 of above 0.500%. There was a correlation between the death rate of snails and soak time. CONCLUSION: The resources of snail-restrained plants are very abundant, and four plants, such as Eucalyptus camaldulensis, Ailanthus altissima, Cinnamomum camphora, and Vetiveria zizanioides have some mollusicidal effect.

Molluscicidal and larvicidal activities and essential oil composition of Cymbopogon winterianus.

UNLABELLED: CONTEXT. Cymbopogon winterianus Jowitt ex Bor (Poaceae), known as citronella grass, is an aromatic herbaceous plant and the essential oil extracted from this grass is used in cosmetics, perfumes, hygiene and cleanliness products worldwide. OBJECTIVE: This study investigated the composition and molluscicidal and larvicidal activities of the essential oil of C. winterianus cultivated in North Brazil. MATERIALS AND METHODS: The oil was obtained by hydrodistillation, analyzed by gas chromatography (GC) and GC-mass spectrometry and then its molluscicidal and larvicidal activities against snails (Biomphalaria glabrata) and hatched larvae of Artemia salina, respectively, were evaluated at concentrations from 10 to 1000 mg/L. RESULTS: The main constituents of oil were citronellal (26.5%), geraniol (16.2%), elemol (14.5%) and citronellol (7.3%). The molluscicidal test revealed significant lethal concentration (LC) values (LC90=97.0 mg/L, LC50=54.0 mg/L and LC20=22.0 mg/L), indicating the presence of molluscicidal compounds in the oil. In addition, the oil showed moderate larvicidal activity (LC50=181.0 mg/L) against the larvae of A. salina, which could justify its use in the aquatic environment without affecting other living organisms. DISCUSSION AND CONCLUSION: The results suggest that the oil of C. winterianus could be an effective alternative to control schistosomiasis, with an average margin of safety to other living organisms that coexist with snails.

Molluscicidal activity of Balanites aegyptiaca against Monacha cartusiana.

CONTEXT: Balanites aegyptiaca (L.) Delile (Zygophyllaceae) is a tropical tree that has many folk uses in various countries. The bark extract is used for the control of the fresh water snails that act as intermediary host of Schistosoma. OBJECTIVE: Study the molluscicidal activity and chemical constituents of seed oil and seed glycosides of B. aegyptiaca against Monacha cartusiana and determine the structure-activity relationship. MATERIALS AND METHODS: Two bioassay methods (residual film application and the leaf dipping technique) were used to evaluate the toxicity effect of the seed oil and glycosides, in concentrations of 1.000, 0.500, 0.250 and 0.125%. The seed oil was analysed by GC/MS. Acid hydrolysis and chromatographic separation were used to study the seed saponins. RESULTS: The bioassay of B. aegyptiaca against the land snail, M. cartusiana, indicated the activity of the seed oil and the high activity of the seed saponins. The seed glycosides gave 30.0, 53.3, 73.0 and 73.3% mortality for concentrations of 0.125, 0.250, 0.500 and 1.00%, respectively. The LC(50) values were 0.335 and 0.256%, respectively. The seed oil was analysed by GC/MS. Acid hydrolysis of the seed saponins gave a mixture of diosgenin, yamogenin and 3,5-spirostadiene. DISCUSSION AND CONCLUSION: To study the structure-activity relationship, a triterpenoidal saponin and a triterpenoidal saponins rich extract (of Zygophyllum coccenum) were proven to be inactive. Thus, the activity is associated with the steroidal, not triterpenoidal saponins. Moreover, a spirostane aglycone without sugar moiety, was found to be inactive and attained the activity by glycosidation.

Molluscicidal activity of Aglaia duperreana and the constituents of its twigs and leaves.

The methanol (MeOH) extract of the twigs and leaves of Aglaia duperreana was investigated for its molluscicidal activity against Pomacea canaliculata. The extract was found to exhibit significant molluscicidal activity. The ethyl acetate soluble fraction of the extract showed the most potent molluscicidal activity among different solvent fractions. The bioactivity-guided chemical investigation of the ethyl acetate soluble fraction led to a new triterpenoid along with 15 known compounds. Their structures were elucidated by spectroscopic methods, including one- and two-dimensional nuclear magnetic resonance techniques as well as mass spectroscopic analysis. The molluscicidal activities of compounds 2-16 against P. canaliculata were also investigated. Naringenin trimethyl ether showed significant molluscicidal activity with a median lethal concentration (LC(50)) of 3.9 µg/mL, which was indicated higher potency than the positive control, tea saponin (LC(50)=4.5 µg/mL).

Molluscicidal activity of methomyl and cardenolide extracts from Calotropis procera and Adenium arabicum against the land snail Monacha cantiana.

In this work, we have evaluated the molluscicidal activity of two cardenolide extracts from Adenium arabicum Balf f. [the benzene (B) and methanol (M) extracts], one cardenolide extract from Calotropis procera (Aiton) W.T. Aiton (extract C), and methomyl against the harmful land snail Monacha cantiana (Montagu). The contact LD50 values for the above mentioned plant extracts were 12.62, 34.63, and 34.35 mg·kg⁻¹ of body weight, respectively, while the LD50 for methomyl was 116.62 mg·kg⁻¹, that is, the plant extracts were 9.24, 3.37, and 3.4 times more toxic than methomyl. In addition, a simple colorimetric method, based on Kedde reagent, was modified to determine cardenolide concentrations in plant extracts. Thin layer chromatography analysis (TLC) showed several cardiac glycosidal compounds in each plant extract. The results proved that cardiac glycosides are promising candidate compounds that could be used to control land snails, or exploited to develop new, effective, and environmentally friendly molluscicides.

Desmettianosides A and B, bisdesmosidic furostanol saponins with molluscicidal activity from Yucca desmettiana.

Bioactivity-guided separation of the aqueous methanolic extract of Yucca desmettiana leaves, which in a preliminary screening exhibited significant molluscicidal activity, led to the isolation and structure elucidation of two new steroidal saponins (1 and 2). The structures of desmettianosides A and B, identified as bisdesmosidic furostanol glycosides with six and five sugar units, respectively, were established by detailed spectroscopic analyses of their NMR and MS data. Compounds 1 and 2 exhibited high molluscicidal activity against Biomphalaria alexandrina snails with LC100 values of 6 and 11 mg/L, respectively.

Isolation, stability and bioactivity of Jatropha curcas phorbol esters.

Jatropha curcas seed oil, which can be utilized for biodiesel production upon transesterification, is also rich in phorbol esters (PEs). In this study, PEs from J. curcas oil (Jatropha factors C1 and C2 (purified to homogeneity), Jatropha factors C3 and (C4+C5) (obtained as mixtures) and PE-rich extract (containing all the above stated Jatropha factors) were investigated. The concentrations of Jatropha PEs were expressed equivalent to Jatropha factor C1. In the snail (Physa fontinalis) bioassay, the order of potency (EC50, µg/L) was: PE-rich extract

Two new triterpenoids from the bark of Eucalyptus exserta and their molluscicidal and cytotoxic activities.

Two new triterpenoids, 2α-hydroxyurs-12-en-28-oic acid-3ß-trans- isoferulate (1) and 2α, 3α, 24-trihydroxyolean-18-en-28-oic acid (2), together with three known triterpenoids (3-5) were isolated from the methanol extract of the bark of Eucalyptus exserta. Their structures were determined by spectroscopic means. Compounds 1, 2, and 5 exhibited molluscicidal activity against Pomacea canaliculata. All isolated compounds showed significant cytotoxic activity against Spodoptera litura (SL) cells.

Efficacy of Euphorbia hirta latex as plant derived molluscicides against freshwater snails.

The toxic effect of binary and tertiary combinations of Euphorbia hirta Linn latex powder with other plant molluscicidal compounds, were evaluated against the freshwater snails Lymnaea (Radix) acuminata and Indoplanorbis exustus in pond. These combinations showed significant time and dose dependent effect against both the snails. These compounds at higher doses were also lethal to freshwater fish Channa punctatus (Bloch) (Channidae {Ophicephalidae}), which shares the habitat with these snails, but the LC90 (24h) doses of snails have no apparent killing properties in fish populations when treated in mixed population of snails and fish.

Efficacy of euphorbia hirta latex as plant derived molluscicides against freshwater snails / Eficácia do látex da Euphorbia hirta como moluscicida vegetal contra caramujos de água doce

The toxic effect of binary and tertiary combinations of Euphorbia hirta Linn latex powder with other plant molluscicidal compounds, were evaluated against the freshwater snails Lymnaea (Radix) acuminata and Indoplanorbis exustus in pond. These combinations showed significant time and dose dependent effect against both the snails. These compounds at higher doses were also lethal to freshwater fish Channa punctatus (Bloch) (Channidae {Ophicephalidae}), which shares the habitat with these snails, but the LC90 (24h) doses of snails have no apparent killing properties in fish populations when treated in mixed population of snails and fish.

Os efeitos tóxicos das combinações binárias e terciárias do pó de látex da Euphorbia hirta Linn assim como outros compostos vegetais moluscicidas foram avaliados em sua ação sobre caramujos de água doce Lymnaea (Radix) acuminata e Indoplanorbis exustus em represas. Estas combinações mostraram significante efeito dose e tempo dependente contra ambos os caramujos. Estes compostos em doses altas foram também letais para peixes de água doce Channa punctatus (Bloch) (Channidae {Ophicephalidae}), que compartilham o ambiente com estes caramujos mas a dose LC90 (24h) para caramujos aparentemente não tem propriedade de matar as populações de peixes quando uma população mista de peixes e caramujos são tratadas.

Molluscicidal activity of various solvent extracts from Solanum nigrum var. villosum L. aerial parts against Galba truncatula.

Molluscicidal activity of Solanum nigrum var. villosum (morelle velue) extracts and their fractions were tested against the mollusca gastropoda Galba truncatula intermediate host of Fasciola hepatica. The results indicated that the hydro-methanol (MeOH-H2O) immature fruit extract possess the highest molluscicidal activity (LC50 = 3.96 mg/L) against Galba truncatula compared with other tested compounds. After acido-basic treatment, the methanolic extract fraction isolated from the immature fruits and the richest in alkaloids was the most toxic (LC50 = 1.65 mg/L). The fractions richest in saponosides obtained from the hydromethanolic and methanolic extracts of immature fruits showed interesting molluscicidal activities (LC50 = 6.15 mg/L and LC50 = 7.91 mg/L, respectively). The observed molluscicide activity could be attributed to the presence of alkaloids or saponosides. So, the immature fruits of Solanum nigrum var. villosum could be substrates of choice for molluscicide activity. In addition, total alkaloids and saponosides present in this plant deserve further investigations in order to identify the active principles and demonstrate their activities on mollusks in their natural habitat. According to the World Health Organization's guidelines on screening for plant molluscicides, use of these fractions may add to the arsenal of methods to control snail transmitting fasciolosis in tropical and Third World countries where fasciolosis is a common disease.