Proyección de extractos de diferentes plantas brasileñas como candidatos para el control de Spodoptera frugiperda (Lepidoptera: Noctuidae).

Los efectos de extractos de las plantas Actinostemon concolor, Geonoma shottiana, Palicourea rigida y Rudgea viburnoides sobre Spodoptera frugiperda fueron evaluados en este estudio. Los extratos se incorporaron en la dieta artificial (1 mg mL-1 de la dieta) y se ofrecieron a larvas de S. frugiperda. El extracto de A. concolor causó 36,1 % de mortalidad. Se detectaron cambios ultraestructurales en los huevos de adultos alimentados en sus estados larvales con extractos de P. rigida y A. concolor. Se observó reducción de la actividad de la tripsina de S. frugiperda después del tratamiento con el extracto de A. concolor. Al cuantificar los fenoles totales en A. concolor, G. shottiana, P. rigida y R. viburnoides, se encontró que A. concolor fue la especie con mayor contenido. El residuo de metanol/agua extracción, que se obtuvo del extracto crudo de A. concolor, contenía compuestos fenólicos que causan cambios en la biología de S. frugiperda similar a los generados por el extracto crudo. En conclusión, A. concolor produce metabolitos secundarios con actividad insecticida sobre S. frugiperda

Toxic effects of Ricinus communis non-protein trypsin inhibitor on Spodoptera frugiperda (J. E. Smith) (Lepidoptera:Noctuidae)

In the study reported herein, we aimed to isolate a trypsin inhibitor from Ricinus communis leaves through chromatographic and spectrometric techniques and evaluate its toxic effects on the development of Spodoptera frugiperda larvae. Plant extracts were submitted to fractionation in adsorption column. The fraction 10, which showed the highest inhibitory activity, were incorporated into an artificial diet at the concentrations of 0, 0.06, 0.12, 0.25 and 0.5%, and offered to S. frugiperda larvae. Fresh weight of larvae, food consumed and weight of eliminated faeces were registered. Based on these parameters the following nutritional index were calculated: Relative Consumption Rate (RCR), Relative Metabolic Rate (RMR), Relative Growth Rate (RGR), Approximated Digestibility (AD), Efficiency of Ingested Food Conversion (EIC), Efficiency of Digested Food Conversion (EDC) and the Metabolic Cost (100 - EDC). The inhibitor at 0.5% concentration was deleterious to S. frugiperda, extending the larval stage in 11 days, with higher RCR and ECD, and lower RGR, ECI and ECD. Therefore, the trypsin inhibitor from leaves of R. communis affected the S. frugiperda larval development, being promising in studies of alternative and sustainable control methods for lepidopteran pest species.Keywords: Castor beans, enzymatic inhibition, integrated pest management, plant defense against herbivor

Biological activities and phytochemical screening of leaf extracts from Zanthoxylum caribaeum L. (Rutaceae)

The Brazilian flora is known for its vast biodiversity; however, many species have been still little studied regarding to their chemical composition and biological potential. Thus, this study aimed to determine the antimicrobial, antioxidant and acaricidal activity of the extracts of leaves of Zanthoxylum caribaeum L. In addition, phytochemical screening of these extracts was carried out to determine the main classes of secondary metabolites present in Z. caribaeum.  Using the Z. caribaeum leaves, the aqueous extract and extracts were obtained in organic solvents (ethanol, methanol, hexane, acetone, dichloromethane and ethyl acetate). The antimicrobial activity of extracts was determined by broth microdilution method, and to detect antioxidant activity the method of capturing the free radical 2,2-diphenyl-1-picryl hydrazyl (DPPH) was used. The acaricidal activity of the extracts was tested on Dermanyssus gallinae (De Geer) (Acari: Dermanissidae). Ethanolic and methanolic extracts presented antimicrobial activity for most of the bacterial strains tested, as well as for yeast Candida albicans. The ethanolic extract presented high free radical sequestration potential (71.2%) and antioxidant capacity (the lowest IC50 value - 24.39 μg mL-1). The extracts obtained with methanol and acetone were the most promising. In general, phytochemical screening indicated the presence of steroids, flavanones, flavones, flavonols, saponins, tannins, triterpenoids and xanthones

Propriedades da Alcachofra com Ênfase na Composição Nutricional/Properties of Artichoke with Emphasis on Nutritional Composition

O uso de plantas medicinais consiste em uma das mais antigas formas de prática medicinal utilizada tanto, para o tratamento quanto, para a cura e prevenção de doenças. Dentre as plantas medicinais de maior relevância, a alcachofra (Cynara scolymus L.) tem recebido destaque, devido aos seus efeitos benéficos sob a saúde humana. Diante disso, o objetivo do estudo foi identificar as propriedades da alcachofra com ênfase na composição nutricional. Para isso, foi realizada uma revisão narrativa através da busca em bancos de dados eletrônicos acerca das propriedades da alcachofra. As bases de dados consultadas foram: Scientific Electronic Library Online (SciELO), Biblioteca Virtual em Saúde (BVS) e outras Revistas Eletrônicas de Saúde, com dimensão temporal entre 2001 e 2018, nos idiomas português e inglês. Pode-se verificar com os dados obtidos, que a alcachofra atua com benefícios frente a doenças hepáticas, saúde intestinal, diabetes, apetite e hipercolesterolemia e suas propriedades bioativas estão associadas diretamente a sua composição química

Extraction and isolation of anti-tryptic castor-bean ( Ricinus communis L.) substances and their effects on Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae)

The search for alternative methods aiming to the control of agricultural pests that cause less environmental impact has been a recurring theme in several studies. For this purpose, the factors influencing the extraction and isolation of the trypsin inhibitor found in castor-bean ( Ricinus communis L.) cake and seeds were studied, and its effect on the development of fall armyworm Spodoptera frugiperda (Smith, 1797) was evaluated. Therefore, the type and proportion of the solvent (w/v), extraction period and oil content were evaluated. The castor-bean cake extract with oil content of 20% in water at a ratio 1:40 (w/v) for 30 min showed the greatest trypsin inhibition, with 21.23 mUTI g-1 seed. The isolation of the trypsin inhibitor contained in the extract was performed by flash chromatography, with inhibition peaks of up to 8906.12 mUTI g-1 fraction, as well as inferring that the best eluent was ethyl acetate with a small percentage of ethanol (< 30%). In order to evaluate the effect of the inhibitor on the development of this insect, the aqueous extract of castor bean cake with oil content of 20% was incorporated into the diet that was provided to the caterpillars at a concentration of 4000 ppm. There was reduction in the oviposition period and an increase in the concentration of proteins in the feces, with 20.55 ± 3.73 d and 177.70 ± 16.90 μmol g-1, respectively. The increase in protein excretion indicates that the trypsin inhibitor was able to reduce the absorption of essential amino acid residues by the insect without, however, impairing the development of S. frugiperda

Extrato de Coffea racemosa como alternativa no controle do bicho-mineiro do cafeeiro Coffea racemosa extract as an alternative for the control of coffee leaf miner

Objetivou-se, com o presente trabalho, verificar o efeito do extrato metanólico de Coffea racemosa Lour., espécie silvestre de cafeeiro portadora de resistência a uma das principais pragas da cultura cafeeira, o bicho-mineiro. Inicialmente, o extrato metanólico das folhas de C. racemosa foi pulverizado em mudas de cafeeiro Coffea arabica cv. Catuaí, em casa-de-vegetação, as quais foram expostas a adultos de L. coffeella para o teste de oviposição com chance de escolha. Observou-se que as plantas tratadas foram menos preferidas para oviposição. A seguir, realizou-se o teste de efeito ovicida, no qual mudas de C. arabica contendo ovos do bicho-mineiro foram pulverizadas com o mesmo extrato. Os experimentos foram conduzidos em delineamento inteiramente casualizado com cinco repetições. Verificou-se redução significativa na eclosão de larvas, e segundo análise por microscopia eletrônica de varredura, os ovos não viáveis apresentaram anomalias nas superfícies externas. Entretanto, os adultos provenientes de ovos tratados não foram afetados na percentagem de emergência, razão sexual e oviposição. Os resultados obtidos demonstram que C. racemosa apresenta-se como uma alternativa promissora ao controle do bicho-mineiro, necessitando, no entanto, de novos estudos para isolamento e identificação das substâncias bioativas.The objective of this study was to evaluate the effect of Coffea racemosa Lour. methanolic extract , a wild coffee specie that presents resistance against the coffee leaf-miner, a major pest of coffee crop. The methanol extract of C. racemosa leaves was sprayed on coffee seedlings, Coffea arabica cv. Catuaí, in greenhouse, which were exposed to adults of L. coffeella for oviposition in free choice test. Plants treated were less preferred for oviposition. An ovicidal assay was carried out by spraying the methanol extract on C. arabica seedlings containing L. coffeela eggs on their leaves. The experiments were conducted in a completely randomized design with five replicates. Larvae hatching out from treated eggs were significantly reduced by the extract and non viable eggs presented some anomalies on their external surfaces according to analyses by scanning electron microscopy. However, the adults derived from treated eggs did not have the percentage of emergence, sex ratio and oviposition affected by the treatment. The results show that C. racemosa presents as a promising alternative to control the coffee leaf-miner, being necessary new studies to isolate and caracterize the bioactive substances against this pest

Extraction and isolation of anti-tryptic castor-bean (Ricinus communis L.) substances and their effects on Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae)

The search for alternative methods aiming to the control of agricultural pests that cause less environmental impact has been a recurring theme in several studies. For this purpose, the factors influencing the extraction and isolation of the trypsin inhibitor found in castor-bean (Ricinus communis L.) cake and seeds were studied, and its effect on the development of fall armyworm Spodoptera frugiperda (Smith, 1797) was evaluated. Therefore, the type and proportion of the solvent (w/v), extraction period and oil content were evaluated. The castor-bean cake extract with oil content of 20% in water at a ratio 1:40 (w/v) for 30 min showed the greatest trypsin inhibition, with 21.23 mUTI g-1 seed. The isolation of the trypsin inhibitor contained in the extract was performed by flash chromatography, with inhibition peaks of up to 8906.12 mUTI g-1 fraction, as well as inferring that the best eluent was ethyl acetate with a small percentage of ethanol (< 30%). In order to evaluate the effect of the inhibitor on the development of this insect, the aqueous extract of castor bean cake with oil content of 20% was incorporated into the diet that was provided to the caterpillars at a concentration of 4000 ppm. There was reduction in the oviposition period and an increase in the concentration of proteins in the feces, with 20.55 ± 3.73 d and 177.70 ± 16.90 μmol g-1, respectively. The increase in protein excretion indicates that the trypsin inhibitor was able to reduce the absorption of essential amino acid residues by the insect without, however, impairing the development of S. frugiperda