Chemical composition of various plant extracts and their in vitro efficacy in control of Fasciola hepatica eggs / Composição química de vários extratos vegetais e sua eficácia in vitro no controle de ovos de Fasciola hepática

ABSTRACT: Fasciolosis has been diagnosed in cattle, goats, sheep and horses in southern and southeastern Brazil. Effective alternative treatments are the targets of study. One promising alternative is the use of plant extracts. The aim of this study was to perform phytochemical analysis of extracts of Eugenia uniflora L., Harpagophytum procumbens, Psidium guajava L. and Stryphnodendron adstringens, and to evaluate the in vitro efficacy of these extracts on ovicidal activity in Fasciola hepatica. Plant extracts were analyzed for phytochemical properties. F. hepatica eggs were collected directly from the gallbladders of animals diagnosed as positive for fasciolosis on post mortem examination. One hundred eggs were incubated with 3 ml of each extract at concentrations of 0.10%, 0.25% and 0.50%, albendazole 0.50% (positive control) or tap water (negative control). To determine anti larval efficacy of each plant extract, hatched eggs were counted and the averages were used. Phytochemical analysis revealed the presence of phenolic compounds, tannins and terpenes in most extracts. E. uniflora L. extract was 100% effective at 0.10%, H. procumbens was effective at 0.25% and P. guajava L. and S. adstringens extracts were 100% effective at all concentrations tested. Taken together, the data suggested that ovicidal activity in F. hepatica is due to the presence of these bioactive compounds.

RESUMO: A fasciolose tem sido diagnosticada em bovinos, caprinos, ovinos e equinos no sul e sudeste do Brasil, sendo que tratamentos alternativos mais eficazes são alvos de estudo. Umas das alternativas promissoras é o uso de extratos vegetais no controle dessa e outras enfermidades. O objetivo deste estudo foi realizar a análise fitoquímica dos extratos de Eugenia uniflora L., Harpagophytum procumbens, Psidium guajava L. e Stryphnodendron adstringens, além de avaliar a eficácia in vitro desses extratos na atividade ovicida em Fasciola hepatica. Os extratos vegetais foram obtidos e analisados para determinação fitoquímica. Ovos de F. hepatica foram coletados diretamente das vesículas biliares de animais diagnosticados como positivos para fasciolose no exame post mortem. Cem ovos foram incubados com três mililitros de cada extrato nas concentrações de 0,10%, 0,25% e 0,50%, de albendazol a 0,50% (controle positivo) e água de torneira (controle negativo). Para determinar a eficácia de cada extrato vegetal os ovos eclodidos foram contados, e a média utilizada para os cálculos de eficácia. A análise fitoquímica revelou a presença de compostos fenólicos, taninos e terpenos na maioria dos extratos. O extrato de E. uniflora L. apresentou eficácia de 100% na concentração de 0,10%, o de H. procumbens a 0,25% e os extratos de P. guajava L. e S. adstringens apresentaram 100% de eficácia em todas as concentrações testadas. Assim, sugere-se que a atividade ovicida em F. hepatica seja devido à presença desses compostos bioativos.

In vitro anthelmintic activity of Lippia gracilis Schauer essential oil against egg-hatching of goat gastrointestinal nematodes / Atividade anti-helmíntica in vitro do óleo essencial de Lippia gracilis Schauer contra a eclosão de nematódeos gastrintestinais de caprinos

Since drug-resistant nematodes became a common problem in sheep and goat industries, alternative methods using natural products have emerged as a viable and sustainable anthelmintic treatment option. Here, the in vitro effect of essential oil extracted from Lippia gracilis Schauer was assessed on the hatching process of nematodes recovered from naturally infected goats. Essential oil at concentrations of 0.08% (0.008 µL/mL), 0.12% (0.012 µL/mL), and 0.16% (0.016 µL/mL) was able to induce an average inhibition of 74.7, 84 and 93%, respectively. The effective concentration required to inhibit egg hatching in 50% of eggs (EC50) was 0.03452%. Therefore, essential oil of L. gracilis showed promisor in vitro anthelmintic results against egg-hatching of goat gastrointestinal nematodes.(AU)

Como os nematoides resistentes a drogas se tornaram um problema comum nas indústrias de ovinos e caprinos, métodos alternativos que utilizam produtos naturais surgiram como uma opção de tratamento anti-helmíntico viável e sustentável. Aqui, o efeito in vitro do óleo essencial extraído de Lippia gracilis Schauer foi avaliado no processo de eclosão de nematoides recuperados de caprinos naturalmente infectadas. O óleo essencial nas concentrações de 0,08% (0,008 µL/mL), 0,12% (0,012 µL/mL), e 0,16% (0,016 µL/mL)foi capaz de induzir uma inibição média de 74,7, 84 e 93%, respectivamente. A concentração efetiva necessária para inibir a eclosão de ovos em 50% dos ovos (CE50) foi de 0,03452%. Portanto, o óleo essencial de L. gracilis apresentou resultados anti-helmínticos in vitro promissores contra a eclosão de nematódeos gastrintestinais de caprinos.(AU)

Exposure of Toxocara canis eggs to Purpureocillium lilacinum as a biocontrol strategy: an experimental model evaluation / Exposição de ovos de Toxocara canis a Purpureocillium lilacinum como estratégia de biocontrole: uma avaliação em modelo experimental

Abstract Purpureocillium lilacinum is a nematophagous fungus used in biological control against some parasites, including Toxocara canis. This study researched the infectivity of embryonated T. canis eggs after exposure to the fungus P. lilacinum. T. canis eggs were exposed to P. lilacinum for 15 or 30 days and subsequently administered to Swiss mice (n=20). Control group consisted of mice who received T. canis embryonated eggs without fungal exposure. Forty-eight hours after infection, heart, lung, and liver from animals of each group were collected to assess larval recovery. The organs of mice that received embryonated eggs exposed to the fungus showed a lower average larval recovery (P<0.05) suggesting that exposure of T. canis eggs to P. lilacinum was able to reduce experimental infection. Under the evaluated conditions, the interaction time between the fungus and the parasite eggs was not a significant factor in larvae recovery. P. lilacinum may be considered a promising T. canis biological control agent. However, further studies are needed to determine a protocol for the use of this fungus as a biological control agent.

Resumo Purpureocillium lilacinum é um fungo nematófago com potencial para uso no controle biológico de parasitos, incluindo Toxocara canis. Este estudo pesquisou a infectividade de ovos de T. canis embrionados após exposição ao fungo P. lilacinum . Ovos de T. canis foram expostos ao fungo por 15 ou 30 dias e subsequentemente administrados a camundongos Swiss (n=20). O grupo controle consistiu de camundongos que receberam ovos embrionados do parasita sem exposição ao fungo. Quarenta e oito horas após a infecção, coração, pulmão e fígado dos camundongos foram coletados para avaliar a recuperação larval. Os órgãos dos animais que receberam ovos embrionados expostos ao fungo apresentaram menor média de recuperação larval (P<0,05) do que os infectados com ovos sem exposição ao fungo, sugerindo que a exposição dos ovos de T. canis a P. lilacinum foi capaz de reduzir a infecção experimental. Nas condições avaliadas, o tempo de interação entre o fungo e os ovos do parasito não foi um fator significativo na recuperação das larvas. P. lilacinum pode ser considerado um promissor agente de controle biológico de T. canis, no entanto, mais estudos são necessários para avaliar o emprego deste fungo como um agente de controle biológico.

In vitro effect of Chrysosporium indicum and Chrysosporium keratinophylum on Toxocara canis eggs / Efecto in vitro de Chrysosporium indicum y Chrysosporium keratinophylum sobre huevos de Toxocara canis

The degree of antagonism exercised by fungi on geohelminth development varies according to the morphological alterations caused by different fungal species. Saprophytic fungi may exert ovicidal or ovistatic effects. The aim of this study was to apply scanning electron microscopy (SEM) to observe the action of two soil saprophytic species of Chrysosporium (C. indicum and C. keratinophylum) on Toxocara canis eggs. The fungal strains to be tested were incubated for 28 days at 28 °C in 2% water agar with a suspension of unembryonated T. canis eggs. A suspension of T. canis eggs in 2% water agar was used as control group. The assay was done in triplicate for each fungus and the control group. SEM observations were performed on the 4th, 7th, 14th, 21st, and 28th day after inoculation. The effect of the fungi on eggs was evaluated in accordance with the alterations observed on the surface and the changes in the normal characteristics of the eggs. Hyphae around the eggs, appresoria penetrating the shell and changes in the typical egg membrane were observed in this assay. Type 3 effect (alterations that occur both in the embryo and the shell, and hyphal penetration of the eggs) was the prevalent effect. SEM allowed us to observe clearly the morphological alterations in T. canis eggs due to the effect of C. indicum and C. keratinophylum. Both saprophytic species of Chrysosporium alter the egg structure and alterations increase as exposure increases.

El grado de antagonismo ejercido por los hongos sobre el desarrollo de los geohelmintos depende de la especie fúngica y las alteraciones morfológicas que causan. Los hongos saprofitos pueden tener efecto ovicida u ovistático sobre los huevos. El objetivo fue aplicar la microscopía electrónica de barrido (MEB) para observar la acción de 2 especies de Chrysosporium (C. indicum y C. keratinophylum) saprofitas de suelos, sobre huevos de Toxocara canis.Las especies a ensayar se sembraron en agar agua al 2% con una suspensión de huevos no embri-onados de T. canis y se incubaron 28 días a 28 °C. Como grupo control se utilizó una suspensión de huevos de T. canis en agar agua al 2%. El ensayo se realizó por triplicado para cada hongo y el grupo control. Las observaciones con MEB se realizaron a los 4, 7, 14, 21 y 28 días de incubación. La acción de los hongos se evaluó según las alteraciones en la superficie y los cambios en las características normales de los huevos. En este ensayo se observaron: hifas rodeando los huevos, appresorios penetrando la cubierta y cambios en la membrana característica del huevo, prevaleciendo el efecto tipo 3 (alteraciones que se producen tanto en el embrión como en la cubierta y penetración de hifas al interior de los huevos). La aplicación de la MEB permitió observar claramente que las 2 especies de Chrysosporium saprofitas de suelos, afectan el normal desarrollo de los huevos de T. canis, alteran su estructura y las alteraciones aumentan con el tiempo de exposición.

Anthelmintic effect of Cassia fistula and Combretum leprosum protein fractions against goat gastrointestinal nematodes / Efeito antihelmíntico das frações proteicas de Cassia fistula e Combretum leprosum contra nematodeos gastrintestinais de caprinos

Abstract In this study, we evaluated the ovicidal and larvicidal activity of protein preparations obtained from Cassia fistula L. and Combretum leprosum Mart. leaves on the gastrointestinal parasites of goats. Protein preparations were obtained after the extraction of C. fistula L. and C. leprosum Mart. leaves, followed by protein fractionation (with ammonium sulfate saturation percentages of 30%, 30%-60%, and 60%-90%) and dialysis, which resulted in protein fractions (called F1, F2, and F3, respectively). The fractions were evaluated by egg hatching (the eggs were recovered in stool samples from naturally infected goats) and larval development tests. The results reveled that the inhibition of hatching of eggs caused by the protein fractions of C. fistula (38%) were similar to that of the control drug, thiabendazole. In addition, the fractions of C. fistula caused significant inhibition (61-69%) of larval development also. However, C. leprosum did not reveal significant inhibition of egg hatching and larval development. We conclude that C. fistula L. showed better ovicidal and larvicidal activity against endoparasites.

Resumo Neste estudo, foram avaliadas as atividades ovicida e larvicida de preparações proteicas de Cassia fistula L. e Combretum leprosum Mart. em parasitas gastrointestinais de caprinos. As preparações proteicas foram obtidas por extração das folhas de C. fistula L. e C. leprosum Mart. seguido pelo fracionamento proteico (com porcentagens de saturação de sulfato de amônio de 30%, 30-60%, 60-90%) e diálise, resultando nas frações proteicas (intituladas F1, F2 e F3, respectivamente). As frações foram avaliadas nos testes de eclosão de ovos (os ovos foram recuperados em amostras de fezes de cabras naturalmente infectadas) e de desenvolvimento larvar. Os resultados revelaram que a inibição da eclosão de ovos causada pelas frações proteicas de C. fistula (38%) foi semelhante à do fármaco controle, o tiabendazol. Além disso, as frações de C. fistula também causaram inibição significativa (61-69%) do desenvolvimento larvar. No entanto, C. leprosum não revelou inibição significativa na eclosão dos ovos e no desenvolvimento larvar. Concluiu-se que C. fistula L. mostrou uma melhor atividade ovicida e larvicida contra endoparasitas.

Evaluation of fractions and 5,7-dihydroxy-4',6-dimethoxy-flavone from Clerodendrum phlomidis Linn. F. against Helicoverpa armigera Hub.

Twelve fractions from chloroform extract of Clerodendrum phlomidis and 5,7-dihydroxy- 4',6-dimethoxy-flavone (pectolinaringenin) were evaluated against Helicoverpa armigera. Maximum antifeedant (89.41%), larvicidal (83.77%) and ovicidal (69.25%) activities were observed in fraction 5. The least LC50 value for antifeedant (178.09 ppm) and larvicidal (198.23 ppm) were observed in fraction 5. No adult emergence was recorded in fractions 4-6 at 1000 ppm. The oviposition deterrent activity was 100% in fraction 5 at all the concentrations. Pectolinaringenin recorded maximum antifeedant (74.68%) and larvicidal (81.11%) activities at 100 ppm; it completely prevented the adult emergence of H. armigera at 100 ppm. Maximum ovicidal activity at 100 ppm concentration was 67.95%. The oviposition deterrent activity was 100% in 100 and 50 ppm concentrations. C. phlomidis could be effectively used to develop a new formulation to control the economically important pests.

Ação anti-helmíntica do extrato hidroalcóolico da raiz da Tarenaya spinosa (Jacq.) Raf. no controle de Haemonchus contortus em ovinos / Anthelmintic action of the hydroalcoholic extract of the root of Tarenaya spinosa (Jacq.) Raf. for Haemonchus contortus control in sheep

Para investigar o potencial anti-helmíntico do extrato hidroalcóolico da raiz de Tarenaya spinosa, como alternativa no controle do nematóide gastrintestinal Haemonchus contortus de ovinos, foram realizados testes in vitro com Artemia salina, em seguida, sobre coproculturas contendo ovos do helminto, avaliando a ação ovicida e larvicida do extrato. Após os testes preliminares, foi realizado o teste in vivo em 20 ovinos machos os quais foram divididos em quatro tratamentos Grupo 1: ivermectina 1%; Grupo 2: sem tratamento; Grupo 3: extrato hidroalcóolico de T. spinosa 150μg/mL; Grupo 4: extrato hidroalcóolico de T. spinosa 300μg/mL, amostras de fezes e de sangue foram coletadas para exames parasitológicos e hematológicos. No teste in vitro, a toxicidade frente a A. salina foi de 150μg/mL, obteve-se eficiência de 81,53% sobre ovos e larvas do H. contortus. No teste in vivo, a avaliação da eficácia dos tratamentos foi realizada pelo teste de redução na contagem de ovos fecais (RCOF), os grupos tratados com Ivermectina e T. spinosa a 150μg/mL e 300μg/mL obtiveram os melhores resultados, reduzindo o OPG após 28 dias em 40,6, 41 e 40,2% respectivamente, revelando assim seu potencial fitoterápico para fins de controle de nematódeos gastrintestinais em ovinos.

To investigate the anthelmintic potential of hydroalcoholic extract of the root of Tarenaya spinosa, as an alternative in the control of gastrointestinal nematode Haemonchus contortus in sheep, in vitro tests were performed with Artemia salina then on stool cultures containing helminth eggs, assessing ovicidal and larvicidal action of the extract. After preliminary tests, the in vivo test was performed in 20 male sheep were divided into four treatments: Group 1 Ivermectin 1 %, Group 2: untreated; Group 3: hydroalcoholic extract of T. spinosa 150μg/mL; Group 4: hydroalcoholic extract T. spinosa 300μg/mL, stool samples and blood were collected for parasitological and haematological tests. In in vitro tests, toxicity against A. salina was 150μg/mL, there was obtained 81.53% efficiency against eggs and larvae of H. contortus. In vivo test, evaluating the effectiveness of treatments was performed by reduction test in faecal egg count (RCOF), the groups treated with Ivermectin and T. spinosa the 150μg/mL and 300μg/mL obtained the best results, reducing OPG after 28 days in 40.6, 41 and 42.6% respectively, thus revealing its herbal potential for control of gastrointestinal nematodes in sheep.

Knowledge, attitudes, perceptions and practices related to ovicidal-larvicidal traps for dengue control among households in one barangay in Quezon city

OBJECTIVE:The study aimed to establish the knowledge, attitudes, perceptions and practices of households in Quezon City on the novel dengue Ovicidal-Larvicidal (OL) traps.METHODOLOGY: This is a descriptive cross-sectional study done in one barangay in Quezon City.  This barangay was purposively chosen for two reasons: 1) it has a  high incidence of dengue and, 2) it is one of the recipient barangays of DOST-developed OL traps distributed by DOH. Data were collected through face to face interview using a pilot-tested interview schedule and observation. Respondents were also purposively included if they were a resident of the barangay, at least 13 years old, have received an OL trap & instructions, and gave consent. A total of 399 respondents were recruited which was more than the computed sample size  of  383.RESULTS: Of the 399 respondents, 92% were females, age ranged from 13 to 82 (mean of 39), 85% were married and 54% finished secondary education. Majority had high level of knowledge on OL traps components, properties, installation, and maintenance. Generally, 65% to 90% of respondents had favorable attitudes and perception towards dengue OL traps. Some misconceptions like OL trap is not safe to human and that it can kill mosquitoes even without adding the pellets were found.CONCLUSIONS: The study generally established good knowledge, positive attitudes and perceptions and correct practices among respondents. Misconceptions need to be corrected to increase the acceptability of using the OL traps at the household level.

Larvicidal & ovicidal efficacy of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) against Anopheles stephensi Liston & Aedes aegypti Linn. (Diptera: Culicidae).

Background & objectives: In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the larvicidal and ovicidal potential of the crude hexane, benzene, chloroform, ethyl acetate and methanol solvent extracts from the medicinal plant Pithecellobium dulce against the mosquito vectors, Anopheles stephensi and Aedes aegypti (Diptera: Culicidae). Methods: Larvicidal activity of P. dulce plant extracts was studied in the range of 60 to 450 mg/l against early third instar larvae of An. stephensi and Ae. aegypti in the laboratory. The larval mortality was observed after 24 h of exposure. The ovicidal activity was determined against An. stephensi and Ae. aegypti to various concentrations ranging from 100 to 750 mg/l under the laboratory conditions. Mean per cent hatchability of the eggs were observed after 48 h post treatment. Results: All leaf and seed extracts showed moderate larvicidal and ovicidal effects; however, the highest larval mortality was found in methanol extract of leaf of P. dulce against the larvae of An. stephensi and Ae. aegypti with the LC50 and LC90 values 145.43, 155.78 mg/l and 251.23, 279.73 mg/l, respectively. The per cent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Zero hatchability was observed at 400 mg/l for leaf methanol extract and 625 mg/l for seed methanol extract of P. dulce against An. stephensi and Ae. aegypti, respectively. Compared to leaf extracts, seed extracts have low potency against the two mosquitoes. Interpretation & conclusions: The present results suggest that the leaf and seed extracts of P. dulce have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes.

Mosquito larvicidal and ovicidal properties of Pemphis acidula Frost. (Lythraceae) against Culex tritaeniorhynchus Giles and Anopheles subpictus Grassi (Diptera:Culicidae)

Objective: This study was undertaken to assess the larvicidal and ovicidal potential of the crude methanol, benzene and acetone solvent extracts from the medicinal plant Pemphis acidula (Pe. acidula) against the medically important mosquito vectors, Culex tritaeniorhynchus (Cx. tritaeniorhynchus) and Anopheles subpictus (An. subpictus) were exposed to various concentrations and (Diptera: Culicidae). Methods: Twenty five late third instar of Cx. tritaeniorhynchus and An. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO 2005. The larval mortality was observed 24 h of treatment. Hundred eggs of Cx. tritaeniorhynchus and An. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of Su and Mulla 1998. The ovicidal activity was observed 48 h of treatment. Results: The LC50 and LC90 values being 10.81and 20.64 and 22.10 and 43.71 ppm and hundred percent of egg mortality was observed at 350 and 400 ppm methanol extract of Pe. acidula against Cx. tritaeniorhynchus and An. subpictus, respectively. Conclusion: These results suggest that the leaf extracts have the potential to be used as an ideal ecofriendly approach for the control of mosquitoes.

Ovicidal activity of Atalantia monophylla (L) Correa against Spodoptera litura Fab. (Lepidoptera:Noctuidae)

Objective: To evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura). Methods:Hexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0%and 0.5%for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC50 and LC90 were calculated using probit analysis. Results:Hexane crude extract showed maximum ovicidal activity of 61.94%at 5.0%concentration with a correlation value of r2=0.81, and least LC50 value of 3.06%. Hexane extract was fractionated using silica gel column chromatography and 12 fractions were obtained. Fraction 9 was active which showed maximum ovicidal activity of 75.61%at 1 000 mg/kg with the LC50 value of 318.65 mg/kg and LC90 value of 1 473.31 mg/kg. In linear regression analysis, significant and high correlation (r2=0.81%) was seen between concentration and ovicidal activity of hexane crude extracts and its active fraction. Conclusions:As per our knowledge, this is the first report for ovicidal activity of A. monophylla against S. litura, A. monophylla could be used for the management of S. litura and other insect pests.

Ovicidal activity of botanical oil formulations against Helicoverpa armigera Hubner and Spodoptera litura Fabricius (Lepidoptera：Noctuidae)

Objective: To evaluate the ovicidal activity of different botanical oil formulations againstHelicoverpa armigera and Spodoptera litura. Methods: Different botanical oils were formulated with different ratio to evaluate the ovicidal activity against H. armigera and S. litura at 5, 10, 15 and 20μl/L concentrations. Results: All the oil formulations showed the ovicidal activity against H. armigera and S. litura. The maximum ovicidal actvity of 76.74 and 69.36% was noticed at 20μl/L concentration in formulation 3 PONNEEM. Formulation 4 Pongam oil showed lower ovicidal activity of 31.34 and 24.76% against H. armigera and S. litura respectively. Among the formulations, PONNEEM exhibited statistically superior ovicidal activity against both insect pests. Conclusions: the present study clearly showed PONNEEM as a pontenial biopesticide to control the egg stage of economically important pests of H. armigera and S. litura. This is the first report for the ovicidal activity of PONNEEM against these two insect pests.

Ovicidal activity of Atalantia monophylla (L) Correa against Spodoptera litura Fab. (Lepidoptera: Noctuidae)

<p><b>OBJECTIVE</b>To evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura).</p><p><b>METHODS</b>Hexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0% and 0.5% for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC50 and LC90 were calculated using probit analysis.</p><p><b>RESULTS</b>Hexane crude extract showed maximum ovicidal activity of 61.94% at 5.0% concentration with a correlation value of r (2)=0.81, and least LC50 value of 3.06%. Hexane extract was fractionated using silica gel column chromatography and 12 fractions were obtained. Fraction 9 was active which showed maximum ovicidal activity of 75.61% at 1 000 mg/kg with the LC50 value of 318.65 mg/kg and LC90 value of 1 473.31 mg/kg. In linear regression analysis, significant and high correlation (r (2)=0.81%) was seen between concentration and ovicidal activity of hexane crude extracts and its active fraction.</p><p><b>CONCLUSIONS</b>As per our knowledge, this is the first report for ovicidal activity of A. monophylla against S. litura, A. monophylla could be used for the management of S. litura and other insect pests.</p>

Efficacy of indigenous plant extracts on the malaria vector Anopheles subpictus Grassi (Diptera: Culicidae).

Background & objectives: Mosquito control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of plant origin may serve as suitable alternative biocontrol techniques in the future. The purpose of the present study was to assess the ethyl acetate, acetone and methanol extracts of Andrographis paniculata, Eclipta prostrata and Tagetes erecta leaves tested for oviposition-deterrent, ovicidal and repellent activities against malaria vector, Anopheles subpictus Grassi (Diptera: Culicidae). Methods: The dried leaves of the three plants were powdered mechanically and extracted with ethyl acetate, acetone and methanol. One gram of crude extract was first dissolved in 100 ml of acetone (stock solution). From the stock solution, test solution concentrations of 31.21- 499.42 mg/l for oviposition- deterrence assay and repellency and 15.60 - 998.85 mg/l were used in ovicidal assay. The percentage oviposition- deterrence, hatching rate of eggs and protection time were calculated. One-way analysis of variance was used for the multiple concentration tests and for per cent mortality to determine significant treatment differences. Results: The percentage of effective oviposition repellency was highest at 499.42 mg/l and the lowest at 31.21 mg/l in ethyl acetate, acetone and methanol extracts of A. paniculata, E. prostrata and T. erecta. The oviposition activity index (OAI) value of ethyl acetate, acetone and methanol extracts of A. paniculata, E. prostrata and T. erecta at 499.42 mg/l were -0.91, -0.93, -0.84, -0.84, -0.87, -0.82, -0.87, -0.89 and -0.87, respectively. Mortality (no egg hatchability) was 100 per cent with ethyl acetate and methanol extracts of A. paniculata, E. prostrata and T. erecta at 998.85 mg/l. The maximum adult repellent activity was observed at 499.42 mg/l in ethyl acetate extracts of A. paniculata, E. prostrata and methanol extracts of T. erecta, and the mean complete protection time ranged from 120 to 150 min with the different extracts tested. Interpretation & conclusions: The acetone extract of A. paniculata, methanol extract of E. prostrata and T. erecta showed good oviposition-deterrent, ovicidal and repellent activities respectively. These results suggest that the leaf extracts of A. paniculata, E. prostrata and T. erecta may have the potential to be used as an ideal eco-friendly approach for the control of the An. subpictus.

Efecto de la colofonia sobre la actividad cardiaca y eclosión de los huevos de Biomphalaria havanensis / Effect of colophony on the heart activity and hatching of Biomphalaria havanensis eggs

INTRODUCCIÓN: estudios recientes en Cuba con colofonia, resina extraída a partir de Pinus caribeae y Pinus tropicalis, han demostrado su actividad molusquicida sobre Biomphalaria havanensis, hospedero intermediario de esquistosomosis. OBJETIVO: determinar la influencia de la colofonia sobre la actividad cardiaca y sobre la eclosión de los huevos de B. havanensis en condiciones de laboratorio. MÉTODOS: se trabajó con las dosis letales (DL50 y DL90) de colofonia, para determinar su influencia en la actividad cardiaca y su carácter ovicida en huevos de B. havanensis. RESULTADOS: como resultado se obtuvo que este producto afecta el desarrollo embrionario de los huevos de 1 y 5 d de puestos, y estos últimos son los menos afectados. Además, se observó una marcada disminución en el número de latidos del corazón por minuto. CONCLUSIÓN: la colofonia puede considerarse como un posible candidato para el control de B. havanensis, por causa de su evidente carácter molusquicida.

INTRODUCTION: in Cuba, recent studies with colophony - a resin from Pinus caribaea and P. tropicalis - have shown its molluscicidal activity on Biomphalaria havanensis, intermediate host of schistosomosis. OBJECTIVE: to determine the impact of colophony on the heart activity and the hatching of B. havanensis eggs in lab. METHODS: lethal doses of colophony (LD50 y LD90) were used to determine their effect on heart activity and their ovicidal capacity on B. havanensis eggs. Heartbeats were counted using stethoscope. The ovicidal effect was observed in one day and 5-day laid eggs. RESULTS: as a result, this product had an impact on the embrionary development of one-day and five-day eggs; the latter were the least affected. In addition, a marked reduction in the number of heartbeats per minute was observed. CONCLUSION: colophony may be considered as possible option for control of B. havanensis because of their molluscicidal properties.

Avaliação da atividade tóxica em Artemia salina e Biomphalaria glabrata de extratos de quatro espécies do gênero Eleocharis (Cyperaceae) / Toxic evaluation of four species of the genus Eleocharis (Cyperaceae) in Artemia salina and Biomphalaria glabrata

O gênero Eleocharis R. Br. compreende cerca de 200 espécies, ocorrendo em ambientes úmidos tais como brejos e margens de rios e lagos. Procurando novos agentes moluscicidas, os extratos de Eleocharis acutangula (Roxb.) Schult., Eleocharis interstincta (Vahl) Roem. & Schult., Eleocharis maculosa (Vahl) Roem. & Schult. e Eleocharis sellowiana Kunth foram testados para atividade moluscicida, contra caramujos adultos e desovas, e toxicidade (ensaio de letalidade com Artemia salina). O extrato hexânico de Eleocharis acutangula (parte subterrânea fresca) foi ativo contra Artemia salina (CL50 = 476,00 mg/mL), enquanto os demais extratos apresentaram CL50 >> 10³ mg/mL, sugerindo baixa toxicidade. O extrato hidro-etanólico de Eleocharis sellowiana (parte subterrânea fresca) foi ativo contra desovas de Biomphalaria glabrata (CL50 = 24,27 mg/mL) mas inativo contra indivíduos adultos. Os demais extratos testados não apresentaram atividade moluscicida.

The genus Eleocharis R. Br. comprises about 200 species, occurring in wet environments like swamps, lakes and river margins. In the search for new molluscicides, extracts from Eleocharis acutangula (Roxb.) Schult., Eleocharis interstincta (Vahl) Roem. & Schult., Eleocharis maculosa (Vahl) Roem. & Schult. and Eleocharis sellowiana Kunth were tested for molluscicidal activity (spawns and adult snails) and toxicity (Brine Shrimp Lethality - BSL - bioassay). The hexane extract of Eleocharis acutangula (fresh subterraneous parts) was active in the BSL bioassay (LC50 = 476 mg/mL), while the other extracts showed LC50 >> 10³ mg/mL, suggesting they have low toxicity. The aqueous ethanol extract of Eleocharis sellowiana (fresh subterraneous parts) was active against Biomphalaria glabrata spawns (LC50 = 24.27 mg/mL) but it was not lethal to adult snails. No other plant extract tested in this study showed molluscicidal activity.