Antimalarial activity of the aqueous extract of the latex of Aloe pirottae Berger. (Aloaceae) against Plasmodium berghei in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: In spite of worldwide efforts, malaria remains one of the most devastating illnesses in the world. The huge number of lives it takes and the resistance of malaria parasites to current drugs necessitate the search for new effective antimalarial drugs. Medicinal plants have been the major source of such drugs and A. pirottae is one of these plants used traditionally for the treatment of malaria in Ethiopia. AIM: This study was aimed at evaluating the antimalarial activity of the aqueous extract of A. pirottae against chloroquine sensitive P. berghei in mice. MATERIALS AND METHODS: The extract was obtained by macerating the latex of A. pirottae with distilled water. To determine its antiplasmodial activity, a 4-day suppressive model was used by dividing 40 mice into five groups of 8 mice each and given 200, 400 & 600mg/kg of the extract, the standard drug (chloroquine 25mg/kg) and the vehicle (distilled water). Then parasite suppression by the extract, survival time and prevention of loss of body weight, rectal temperature and packed cell volume were assessed. All data were presented as the Mean ±â€¯SEM (Standard Error of the Mean) and analyzed using IBM SPSS version 20. RESULTS: The extract showed moderate antimalarial activity by significantly (p < 0.001) suppressing parasitemia at all dose levels with maximum parasitemia suppression of 47.0% and significantly (p < 0.01) increasing survival time. Furthermore, 400 mg/kg and 600 mg/kg doses showed significant (p < 0.01) prevention of loss in body weight, rectal temperature and packed cell volume. CONCLUSION: Based to the results of this study, A. pirottae is endowed with a moderate antimalarial activity that is in agreement with the traditional claim of A. pirottae, hence may be used as a basis for further studies to be conducted on antimalarial activity of the plant.

Evaluation of the cytotoxicity, oral toxicity, genotoxicity, and mutagenicity of the latex extracted from Himatanthus drasticus (Mart.) Plumel (Apocynaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Himatanthus drasticus is a tree popularly known as janaguba. Endemic to Brazil, it is found in the Cerrado and Caatinga biomes, rock fields, and rainforests. Janaguba latex has been used in folk medicine for its antineoplastic, anti-inflammatory, analgesic, and antiallergic activities. However, studies investigating the safety of its use for medicinal purposes are limited. AIM OF THE STUDY: This study aimed to evaluate the toxicity of the latex extracted from H. drasticus. MATERIALS AND METHODS: The latex was extracted from H. drasticus specimens by removing a small area of bark (5 × 30 cm) and then dissolving the exudate in water and lyophilizing it. Phytochemical screening was performed by TLC and GC-MS, protein, and carbohydrate levels. Cell viability was performed by the MTT method. Acute oral toxicity, genotoxicity, and mutagenicity assays were performed in mice. RESULTS: TLC showed the presence of saponins and reducing sugars, as well as steroids and terpenes. The GC-MS analysis of the nonpolar fraction identified lupeol acetate, betulin, and α/ß-amyrin derivatives as the major compounds. The latex was toxic to S-180 cells at 50 and 100 µg/mL. No signals of toxicity or mutagenicity was found in mice treated with 2000 mg/kg of the latex, but genotoxicity was observed in the Comet assay. CONCLUSIONS: H. drasticus latex showed toxicity signals at high doses (2000 mg/kg). Although the latex was not mutagenic to mice, it was genotoxic in the Comet assay in our experimental conditions. Even testing a limit dose of 2000 mg/kg, which is between 10 to 35-fold the amount used in folk medicine, caution must be taken since there is no safe level for genotoxic compounds exposure. Further studies on the toxicological aspects of H. drasticus latex are necessary to elucidate its possible mechanisms of genotoxicity.

Corneal Toxicity after Self-Application of Calotropis procera (Ushaar) Latex: Case Report and Analysis of the Active Components.

Calotropis procera (ushaar) produces a copious amount of latex, which has both inflammatory and anti-inflammatory pharmacological properties. Local application produces an intense inflammatory response and causes significant ocular morbidity. We report corneal toxicity following self-application of latex from C. procera in a 74-year-old man. He reported painless decreased vision in the affected eye with diffuse corneal edema, and specular microscopy revealed a reduced endothelial cell count. After he was treated with topical corticosteroids, his visual acuity improved from hand motion to 20/80. The composition of the active compounds in the latex was analyzed. When topically administered, the latex may cause severe ocular injuries and a loss of endothelial cells over a period of time. Public education, early recognition of such injuries, and timely intervention may prevent permanent ocular damage.

Toxicity of Jatropha curcas L. latex in Allium cepa test / Toxicidade do látex de Jatropha curcas L. no modelo de Allium cepa

The latex obtained from Jatropha curcas (physic nut) is used in traditional medicine to treat a variety of disturbs, including burns, hemorrhoids, ringworm and ulcers. Phytochemical analyses have shown that J. curcas latex contains natural compounds with therapeutic potential. In this study, the toxicity, cytotoxicity and genotoxicity effects of J. curcas latex on the root cells of Allium cepa were examined. Onion seeds and bulbs were exposed to seven different concentrations of latex and then the roots were submitted to macro and microscopic analyses. Water and sodium azide were used as negative and positive controls, respectively. The analysis of root growth showed that J. curcas crude latex or 50% diluted is highly toxic. Cytogenetic results showed that the mitotic index of the onion roots submitted to latex treatment decreased significantly compared to the negative control, which suggests that the latex is cytotoxic. High incidence of chromosome aberrations in the cells treated with J. curcas latex was observed too, indicating that the latex also presents genotoxic effect. The analyses presented in this report suggest the toxic, cytotoxic and genotoxic effects of J. curcas latex. Then, the indiscriminate use of J. curcas latex in folk medicine could bring risk to human health.

O látex obtido de Jatropha curcas (pinhão manso) é usado na medicina tradicional para tratamento de diversos distúrbios, como queimaduras, hemorroida, micose e úlcera. Análises fitoquímicas apontaram que o látex de J. curcas contém compostos naturais com potencial terapêutico. Este estudo avaliou a toxicidade, citotoxicidade e genotoxicidade do látex de J. curcas em células da raiz de Allium cepa. Sementes e bulbos de cebola foram expostos á sete diferentes concentrações de látex e, então, as raízes foram submetidas a análises macro e microscópica. Água e azida sódica foram utilizadas como controle negativo e positivo, respectivamente. A análise do comprimento das raízes mostrou que o látex de J. curcas puro e diluído a 50% é altamente tóxico. O índice mitótico das raízes de cebola submetidas ao tratamento com o látex diminuiu significativamente comparado com o controle negativo, o que sugere que o látex é citotóxico. Uma alta incidência de aberrações cromossômicas em células tratadas com o látex de J. curcas também foi observada, indicando que o látex apresenta efeito genotóxico. Essa análise sugere que o látex de J. curcas possui efeitos tóxico, citotóxico e genotóxico, sendo que o uso indiscriminado do látex de J. curcas na medicina popular pode trazer risco à saúde humana.

Latex proteins from Calotropis procera: Toxicity and immunological tolerance revisited.

Many thousands of plants are disseminated worldwide in traditional and folk medicines based on the belief that their leaves, roots, seeds, bark or secretions, when adequately handled, can treat, alleviate or ameliorate numerous disease symptoms. Calotropis procera (Apocynaceae) is a popular medicinal plant and the claims of this shrub's phytomedicinal properties have been scientifically validated. In this study, further prospects towards the in vivo toxicity and oral immunological tolerance of phytomodulatory proteins isolated from the latex of C. procera are reported. Acute toxicity was determined in mice by oral and intraperitoneal administration of latex proteins (LP) and was followed behavioral, hematological and histological analyses. Oral immunological tolerance to LP was assessed by intraperitoneal immunization in mice that had received LP orally before. Animals given 5000 mg/kg orally exhibited only discrete behavioral alterations and augmentation of monocytes. Death was not notified 14 days after exposure. However, all animals receiving LP 150 mg/kg by i.p. died in 1 h. Death (20%) was documented when LP (75 mg/kg) was given in the peritoneum and signs of harmful effects were observed in the survivors (80%). Oral immunological tolerance was observed in animals previously given LP orally, when they were further immunized/challenged with peritoneal exposure to different doses of LP. This was confirmed by the lowering of IgE and IgG in the serum, IL-4 and IFN-γ in spleen homogenates and the absence of anaphylaxis signs. It is therefore concluded that LP exhibited quite discrete adverse effects when orally administrated at higher concentrations and this route of administration did not stimulate adverse immunological reactions. Instead it was observed immunological tolerance. The present study contributes very important information concerning the safe use of C. procera as a phytotherapeutic agent.

Evaluation of cytotoxicity and genotoxicity of Hancornia speciosa latex in Allium cepa root model.

The latex obtained from Hancornia speciosa Gomes (Mangabeira tree) is widely used in traditional medicine to treat a variety of diseases, including diarrhea, ulcer, gastritis, tuberculosis, acne and warts. In this study, the cytotoxicity and genotoxicity effects of H. speciosa latex on the root meristem cells of Allium cepa were examined. Onion bulbs were exposed to different concentrations of latex and then submitted to microscopic analysis using Giemsa stain. Water was used as a negative control and sodium azide as a positive control. The results showed that, under the testing conditions, the mitotic index (MI) of the onion roots submitted to latex treatment did not differ significantly from the negative control, which suggests that the latex is not cytotoxic. Low incidence of chromosome aberrations in the cells treated with H. speciosa latex was also observed, indicating that the latex does not have genotoxic effect either. The MI and the chromosome aberration frequency responded to the latex concentration, requiring more studies to evaluate the dosage effect on genotoxicity. The results indicate that in tested concentrations H. speciosa latex is probably not harmful to human health and may be potentially used in medicine.

Evaluation of cytotoxicity and genotoxicity of Hancornia speciosa latex in Allium cepa root model / Avaliação da citotoxicidade e genotoxicidade do látex de Hancornia speciosa usando o modelo da raiz de Allium cepa

Abstract The latex obtained from Hancornia speciosa Gomes (Mangabeira tree) is widely used in traditional medicine to treat a variety of diseases, including diarrhea, ulcer, gastritis, tuberculosis, acne and warts. In this study, the cytotoxicity and genotoxicity effects of H. speciosa latex on the root meristem cells of Allium cepa were examined. Onion bulbs were exposed to different concentrations of latex and then submitted to microscopic analysis using Giemsa stain. Water was used as a negative control and sodium azide as a positive control. The results showed that, under the testing conditions, the mitotic index (MI) of the onion roots submitted to latex treatment did not differ significantly from the negative control, which suggests that the latex is not cytotoxic. Low incidence of chromosome aberrations in the cells treated with H. speciosa latex was also observed, indicating that the latex does not have genotoxic effect either. The MI and the chromosome aberration frequency responded to the latex concentration, requiring more studies to evaluate the dosage effect on genotoxicity. The results indicate that in tested concentrations H. speciosa latex is probably not harmful to human health and may be potentially used in medicine.

Resumo O látex obtido de Hancornia speciosa é amplamente utilizado na medicina popular para tratar uma variedade de doenças, tais como: diarreia, úlcera, gastrite, tuberculose, acne e verrugas. Nesse estudo, foram avaliados os efeitos citotóxicos e genotóxicos do látex de H. speciosa sobre as células meristemáticas das raízes de Allium cepa. Os bulbos das cebolas foram expostos a diferentes concentrações de látex e depois submetidos à analise microscópica usando o corante Giemsa. A água foi usada como controle negativo e a ázida sódica como controle positivo. Os resultados mostraram que o índice mitótico (IM) das raízes de cebola submetidas ao tratamento com látex, nas condições testadas, não diferiram significativamente do controle negativo, e sugerem que o látex não é citotóxico. Também foi observada uma baixa incidência de aberrações cromossômicas nas células tratadas com látex de H. speciosa, o que sugere que o látex também não possui efeito genotóxico. O IM e a frequência de aberrações cromossômicas foram dependentes da concentração de látex. Outros estudos devem ser realizados para avaliar o efeito da dose na genotoxidade. Os resultados indicam que o látex de mangabeira, nas concentrações testadas, provavelmente não é danoso para saúde humana e pode ter potencial para ser usado na medicina.

Is folklore use of Euphorbia helioscopia devoid of toxic effects?

OBJECTIVE: To evaluate acute toxic effects of Euphorbia helioscopia in order to assure the safety and usefulness of herbal remedy. MATERIALS AND METHODS: The Organization for Economic Cooperation and Development (OECD) for chemical testing guidelines No. 425 for acute oral toxicity testing were followed in this study. Mice were divided into three groups (n = 5). Group I served as control. Groups II and III were administered methanol extract of E. helioscopia leaves and latex orally at dose of 2000 mg/kg, respectively. Then, all the animals were observed for two weeks. Blood sampling was done by cardiac puncture after 14 days from each group for biochemical analysis. Histopathology was performed to find out any microscopic lesion in vital organs. RESULTS AND DISCUSSION: LD50 was found greater than 2000 mg/kg. There was decrease in cholesterol, triglycerides, LDL and VLDL levels of latex and leaves with methanol extract-treated animals, with respect to control indicating plant's hypolipidemic effect. On macroscopic examination, no lesions were found on vital organs, such as liver, heart and kidney; and normal architecture was observed on microscopic examination. CONCLUSION: On the basis of results, it was concluded that methanol extract of E. helioscopia leaves and latex were devoid of toxic effects in acute toxicity study.

Evaluation of hemostatic activity of latex from three Euphorbiaceae species.

ETHNOPHARMACOLOGICAL RELEVANCE: Latices from several plant species of Euphorbiaceae family have been traditionally applied over fresh cuts to stop bleeding and subsequently applied over wounds to enhance healing process. The latex arrested bleeding from fresh wounds by reducing bleeding and whole blood coagulation time which are important indices of hemostatic activity. It has been accepted that hemostatic activity is due to the proteolytic fraction of plant latices. Thus, the present study aimed to assess the clot inducing properties of three Euphorbiaceae plants viz., Euphorbia nivulia Buch.-Ham., Pedilanthus tithymaloides (L.) Poit and Synadenium grantii Hook F. MATERIALS AND METHODS: In the present study, various proteolytic activities namely protease, gelatinase, milk clotting and whole blood clotting assay of the enzyme fraction of latices of Euphorbia nivulia, Pedilanthus tithymaloides and Synadenium grantii have been investigated. The inhibition profile of protease specific inhibitors was assessed. Also, the effects of protein fractions were studied using bleeding/clotting time test of fresh experimentally-induced wounds in mice. RESULTS: Euphorbia nivulia latex protease has noticeable blood clotting activity followed by Pedilanthus tithymaloides and Synadenium grantii. Stem latex protease of Pedilanthus tithymaloides exhibits superior procoagulant activity in different mammal's blood samples viz., Capra hircus, Bubalus bubalis, Ovibos moschatus and Bos indicus. Blood sample of ox was the most sensitive to latex protease than other mammal's blood. Concomitantly, the plant latex protease could significantly reduce whole blood clotting time of human and mice blood samples. CONCLUSION: The protease fraction of latices of Euphorbia nivulia, Pedilanthus tithymaloides and Synadenium grantii possesses phytoconstituents capable of arresting wound bleeding, and accelerating whole blood coagulation process. It suggests good potentiality for use of latex proteases in wound management. Also, the finding of this study showed that the protease enzyme of Pedilanthus tithymaloides has the most potent hemostatic agent.

Análise da atividade in vitro de altas diluições de Euphorbia tirucalli L. em cultura de células de melanoma humano / Analysis of in vitro activity of high dilutions of Euphorbia tirucalli L. in human melanoma cells

Aveloz é uma planta da família Euphorbiaceae, caracterizada pela produção de um látex tóxico, que quando em contato com mucosas e pele tem ação corrosiva. O uso tópico e contínuo deste látex vem sendo indicado na medicina popular para tratamento de verrugas, e epiteliomas. Para validar o uso popular da Aveloz, o látex ultradiluído e o medicamento homeopático Euphorbia tirucalli L. foram testados in vitro sobre a proliferação de células de melanoma. O látex ultradiluído foi obtido através do processo de diluiçaõ e agitação (método de trituração para fase sólida e sucussão para fase líquida), usando EtOH 70ºGL( Álcool etílico de alcoolatura de 70° Gay Lussac) como insumo inerte nas diluições homeopáticas de 5cH, 15cH e 30cH, conforme preconizado pela Farmacopeia Homeopática Brasileira(FHB). O medicamento homeopático Euphorbia tirucalli foi obtida a partir da tintura-mãe e preparado pelo método hahnemanniano na escala centesimal. Soluções de EtOH 70º GL (0,5 e 5%) foram sucussionadas e usadas como controle neste experimento. Células de melanoma humano foram cultivadas, tratadas e monitoradas pelo método MTT no intervalo de tempo de 24h a 72h. Observou-se que a solução de EtOH 0,5% teve pouco ou nenhum efeito sobreInt J High Dilution Res 2011; 10(36):183-193Proceedings of the XXV GIRI Symposium and VIII CBFH; 2011 Sep 04-07; Foz do Iguaçu (Brazil)190a proliferação de células de melanoma (inibição máxima de 5,1% no grupo 30cH ). Na maioria dos grupos, observou-se uma correlação positiva entre o grau de inibição da proliferação e a diluição dos preparativos, máximo de aumento de 9% no grupo do látex 5%. Além disso, a tintura mãe foi mais ativa do que o látex , no tratamento com 0,5% de látex 30cH mostrou uma inibição de 19,7%, enquanto no tratamento com 0,5% do medicamento homeopático Euphorbia tirucalli 30cH houve uma inibição de 32,1% da proliferação celular (p<0.05). Estes resultados sugerem um possível uso terapêutico do Aveloz em ultra-diluições. (AU)

Aveloz (firestick cactus; Euphorbia tirucalli L.) belongs to Euphorbiaceae family, characterized by the production of a toxic latex that has corrosive effects on the skin and mucous membranes. Continual topic use of the latex is recommended by popular medicine to treat warts, and epitheliomas. To validate this indication, ultra diluted latex and homeopathic medicine Euphorbia tirucalli were tested in vitro on the proliferation of melanoma cells. Ultra diluted latex was prepared in homeopathic dilutions 5cH, 15cH and 30cH by dilution and agitation (trituration for solid and sucussion for liquid phases) using 70º GL (Gay Lussac) ethylic alcohol (70º GL EtOH 70ºGL) as inert medium according to the guidelines in Farmacopéia Homeopática Brasileira (FHB). Homeopathic medicine Euphorbia tirucalli was prepared from mother-tincture according to the centesimal Hahnemannian method. Solutions 0.5% and 5% of 70ºGL EtOH were succussed and used as control. Human melanoma cells were cultured, treated and monitored by method MTT for 24 to 72 hours. It was observed that 0.5% 70ºGL EtOH solution had little or no effect on the proliferation of melanoma cells (5.1% maximal inhibition in dilution 30cH). Positive correlation was observed in most groups between inhibition of proliferation and diluted preparations, maximal increase (9%) was seen in with 5% latex. Moreover, mother-tincture proved to be more active than latex; treatment with 0.5% solution of latex 30cH exhibited 19.7% inhibition, whereas treatment with 0.5% solution of Euphorbia tirucalli 30cH exhibited 32.1% inhibition of cell proliferation (p<0.05). These results suggest that high dilutions of firestick cactus (especially dilution 30cH) might have a therapeutic indication in melanoma, further studies are needed in this regard.(AU)

Potato disc bioassay and cytotoxic effect of Leptadenia pyrotechnica: comparative study of diverse extracts.

Comparative acute toxicity studies of the latex and sequential extracts of Leptadenia pyrotechnica (Forsk.) Decne (Asclepiadaceae) were recorded using brine shrimp. The higher toxicities were exhibited in latex; methanol, methanol/dichloromethane (1:1), defatted methanol/dichloromethane (1:1), defatted methanol and dichloromethane extracts. The other extracts; aqueous, alkaloids, ethyl acetate and n-butanol exhibited less toxicities compared with the other extracts. The estimated LC50 and its 95% confidence limits for these extracts expressed in ppm were: methanol, latex 18.84 (11.22-31.61), methanol/dichloromethane 19.95 (7.76-53.70), defatted methanol/dichloromethane 21.38 (7.24-63.10), defatted methanol 28.19 (16.27-48.81) and dichloromethane 30.90 (11.75-79.43). The anti-tumor activities; potato disc assays of methanol, ethyl acetate and alkaloids extracts showed good activities as anti-tumor agent which represented-49.30,-43.20 an -33.60%, respectively. While latex and aqueous extract represented-30.80 and-28.17%, respectively.

Toxicity of aqueous extract of Euphorbia tirucalli latex on catfish, Heteropneustes fossilis.

A four-day static renewal acute toxicity test was performed to determine the LC(50) value of aqueous extract of Euphorbia tirucalli latex for the freshwater fish, Heteropneustes fossilis. The LC(50) values, their upper and lower confidence limits and slope functions were calculated. The LC(50) values for aqueous extract of E. tirucalli latex at various exposure periods are 3.450 µl/L for 24 h, 2.516 µl/L for 48 h, 1.623 µl/L for 72 h and 1.315 µl/L for 96 h. The toxicity of aqueous extract of E. tirucalli latex exhibits a positive correlation between fish mortality and exposure periods. It is concluded that latex of E. tirucalli has higher piscicidal activity as compared with other synthetic pesticides, organophosphates and pyrethroids for the fish H. fossilis. Hence, adequate precautions must be exercised when E. tirucalli latex is being used near fish-inhabiting water reservoirs.

Skin exposure to micro- and nano-particles can cause haemostasis in zebrafish larvae.

Low mass ambient exposure to airborne particles is associated with atherothrombotic events that may be a consequence of the combustion-derived nanoparticle content. There is concern also over the potential cardiovascular impact of manufactured nanoparticles. To better understand the mechanism by which toxic airborne particles can affect cardiovascular function we utilised zebrafish as a genetically tractable model. Using light and confocal fluorescence video-microscopy, we measured heart-rate and blood flow in the dorsal aorta and caudal artery of zebrafish larvae that had been exposed to a number of toxic and non-toxic microparticles and nanoparticles. Diesel exhaust particles (DEP), carboxy-charged Latex beads (carboxy-beads) and toxic alumina (Taimicron TM300), but not non-toxic alumina (Baikalox A125), were found to promote both skin and gut cell damage, increased leukocyte invasion into the epidermis, tail muscle ischaemia and haemostasis within the caudal artery of free swimming zebrafish larvae. The presence of sodium sulfite, a reducing agent, or warfarin, an anticoagulant, within the system water abrogated the effects of both toxic alumina and carboxy-beads but not DEP. Genetic manipulation of skin barrier function augmented skin damage and haemostasis, even for the non-toxic alumina. The toxic effects of carboxy-beads were still apparent after leukocyte numbers were depleted with anti-Pu.1 morpholino. We conclude that particle uptake across skin epithelium and gut mucosal barriers, or the presence of leukocytes, is not required for particle-induced haemostasis while a compromised skin barrier function accentuated tissue injury and haemostasis.

Effect of aqueous suspension of dried latex of Calotropis procera on hepatorenal functions in rat.

AIM OF THE STUDY: The present study was carried out to evaluate the effect of dry latex (DL) of Calotropis procera, a plant of the family Asclepiadaceae, on the functions of liver and kidney in normal rats. MATERIALS AND METHODS: Aqueous suspension of DL was orally administered to rats at doses of 10, 100 and 400 mg/kg for a period of 45 days and the effect on various parameters reflecting liver and kidney functions was compared with that of normal controls. RESULTS: Treatment with DL did not alter the serum levels of aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), creatinine, urea and urinary levels of glucose and protein as compared to the normal rats. It exhibited a modulatory role in maintaining the levels of blood glucose and serum insulin. The liver and kidney of DL treated and normal rats were also comparable with regard to the tissue levels of oxidative stress markers and histology. Further, no signs of toxicity were observed in the DL treated rats over the study period. CONCLUSION: Our study reveals that aqueous suspension of Calotropis procera latex does not produce any toxicity and could be safely used for therapeutic purpose at the doses studied.

The lethality of Euphorbia conspicua to adults of Biomphalaria glabrata, cercaria of Schistosoma mansoni and larvae of Artemia salina.

Leaf extracts of Euphorbia conspicua (Euphorbiaceae), together with the latex and fractions derived therefrom, were evaluated for their molluscicidal and cercaricidal activities and their toxicities to brine shrimps. Whilst the leaf extracts were inactive against Biomphalaria glabrata, the latex, its triterpenic fraction and irritant fractions I and II exhibited high activities against adult snails with LC90 values of 4.87, 10.55, 0.64 and 0.10 microg/mL, respectively. The latex and its derived fractions were considered lethal to the cercaria of Schistosoma mansoni at concentrations of 100 microg/mL. The toxicities of the latex and the irritant fractions, but not of the triterpenic fraction, against Artemia salina were high with LC50 values < 10 microg/mL. The possible application of the latex of E. conspicua as an alternative natural molluscicide is considered.

Latex constituents from Calotropis procera (R. Br.) display toxicity upon egg hatching and larvae of Aedes aegypti (Linn.).

Calotropis procera R. Br. (Asclepiadaceae) is a well-known medicinal plant with leaves, roots, and bark being exploited by popular medicine to fight many human and animal diseases. This work deals with the fractionation of the crude latex produced by the green parts of the plant and aims to evaluate its toxic effects upon egg hatching and larval development of Aedes aegypti. The whole latex was shown to cause 100% mortality of 3rd instars within 5 min. It was fractionated into water-soluble dialyzable (DF) and non-dialyzable (NDF) rubber-free materials. Both fractions were partially effective to prevent egg hatching and most of individuals growing under experimental conditions died before reaching 2nd instars or stayed in 1st instars. Besides, the fractions were very toxic to 3rd instars causing 100% mortality within 24 h. When both fractions were submitted to heat-treatment the toxic effects were diminished considerably suggesting low thermostability of the toxic compounds. Polyacrylamide gel electrophoresis of both fractions and their newly fractionated peaks obtained through ion exchange chromatography or desalting attested the presence of proteins in both materials. When submitted to protease digestion prior to larvicidal assays NDF lost most of its toxicity but DF was still strongly active. It may be possible that the highly toxic effects of the whole latex from C. procera upon egg hatching and larvae development should be at least in part due to its protein content found in NDE However the toxicity seems also to involve non protein molecules present in DF.

Latex constituents from Calotropis procera (R. Br.) display toxicity upon egg hatching and larvae of Aedes aegypti (Linn.)

Calotropis procera R. Br. (Asclepiadaceae) is a well-known medicinal plant with leaves, roots, and bark being exploited by popular medicine to fight many human and animal diseases. This work deals with the fractionation of the crude latex produced by the green parts of the plant and aims to evaluate its toxic effects upon egg hatching and larval development of Aedes aegypti. The whole latex was shown to cause 100 percent mortality of 3rd instars within 5 min. It was fractionated into water-soluble dialyzable (DF) and non-dialyzable (NDF) rubber-free materials. Both fractions were partially effective to prevent egg hatching and most of individuals growing under experimental conditions died before reaching 2nd instars or stayed in 1st instars. Besides, the fractions were very toxic to 3rd instars causing 100 percent mortality within 24 h. When both fractions were submitted to heat-treatment the toxic effects were diminished considerably suggesting low thermostability of the toxic compounds. Polyacrylamide gel electrophoresis of both fractions and their newly fractionated peaks obtained through ion exchange chromatography or desalting attested the presence of proteins in both materials. When submitted to protease digestion prior to larvicidal assays NDF lost most of its toxicity but DF was still strongly active. It may be possible that the highly toxic effects of the whole latex from C. procera upon egg hatching and larvae development should be at least in part due to its protein content found in NDF. However the toxicity seems also to involve non protein molecules present in DF.

Molluscicidal evaluation of three common plants from India.

Mortality caused by the aqueous extract of latex of Thevetia peruviana, Alstonia scholaris and Euphorbia pulcherrima against two harmful freshwater snails, Lymnaea acuminata and Indoplanorbis exustus, is reported. Latices of all the plants at high doses were also lethal to freshwater fish Channa punctatus, which shares the habitat with these snails, but within 24 h, LC90 of snail L. acuminata did not cause any mortality to fishes in a mixed population of snail and fish. Therefore, these plant extracts may eventually be of great value for the control of harmful aquatic snails and other molluscan pests.

Anthelmintic activity of Calotropis procera (Ait.) Ait. F. flowers in sheep.

The anthelmintic activity of Calotropis (C.) procera flowers in comparison with levamisole was evaluated through in vitro and in vivo studies. In vitro studies revealed anthelmintic effects (P<0.05) of crude aqueous (CAE) and crude methanolic extracts (CME) of Calotropis procera flowers on live Haemonchus (H.) contortus as evident from their mortality or temporary paralysis. For in vivo studies, Calotropis procera flowers were administered as crude powder (CP), CAE and CME to sheep naturally infected with mixed species of gastrointestinal nematodes. Egg count percent reduction (ECR) was recorded as 88.4 and 77.8% in sheep treated with CAE and CP at 3gkg(-1) body weight on day 7 and 10 post-treatment (PT), respectively. CME was least effective resulting in 20.9% reduction in ECR on day 7 PT. It was found that Calotropis procera flowers possess good anthelmintic activity against nematodes, yet it was lower than that exhibited by levamisole (97.8-100%). It is suggested that further research on large scale be carried out involving a large number of animals, doses higher than those used in the current study, identification of active principles, and standardization of dose and toxicity studies for drug development.

The toxicity of four native Indian plants: effect on AChE and acid/alkaline phosphatase level in fish Channa marulius.

The latex of four plants viz. Euphorbia royleana, Jatropha gossypifolia (Euphorbiaceae), Nerium indicum and Thevetia peruviana (Apocynaceae) caused significant reduction in acid/alkaline phosphatase activity and anti-acetylcholinesterase activity in nervous tissue of freshwater air breathing fish Channa marulius. The reduction in the activity of both phosphatases and AChE were time as well as dose dependent.