Larvicide and insecticide activity of the essential oil of Ocimum sanctum var. cubensis in the control of Musca domestica (Linnaeus, 1758), under laboratory conditions

Essential oils have been considered as an important alternative facing synthetic pesticides. The control of the species Musca domestica is very important for public health due to their role as vector associated with Vibrio cholerae, Salmonella and Shigella, among other pathogens. The objective of this work was to evaluate the larvicidal and insecticidal efficacy of the essential oil of Ocimum sanctum var. cubensis, in the control of Musca domestica and its effect on the post-embryonic development of this species. The essential oil was applied topically in six concentrations to newly hatched larvae (1μL / larva). Mortality, interval length of each development period, as well as the weight of mature larvae were analyzed. An insecticidal bioassay was also carried out in adult flies. The essential oil of O. sanctum caused a slight reduction in the larval and pupal period for some of the concentrations evaluated. The time of development of the newly hatched larvae until the adult period was shortened in all the concentrations analyzed. The larvae of the control group were the heaviest. The effectiveness of the product in the control of the larvae of the flies of the species M. domestica was greater than 50%, except for those larvae treated with 80.25 mg/mL of the essential oil. The lethal concentration for adult insects LC50 was estimated at 9.41μg. Results demonstrated that the essential oil of O. sanctum has effect in all stages of the life cycle of M. domestica, extolling its potential as an effective insecticide against this species.&nbsp

Potencial antioxidante do extrato da folha de Spondias mombin L. em etanol 70%

Introduction: the species Spondias mombin L. is a plant that grows in Cuba, and to which a considerable number of ethnopharmacological applications and high antioxidant power are reported. However, most of these reports are oriented to the fruit, which stands out for its nutritional value. Objective: to evaluate the antioxidant activity of an extract of Spondias mombin L. leaves in 70% ethanol. Method: the antioxidant activity was evaluated by six different methods: determination of the oxidation index, reducing power, inhibition of DPPH and ABTS radicals, hydrogen peroxide reducing capacity and oxygen radical neutralization capacity. Concentrations from 1000 to 62.5 µg/mL were evaluated, prepared from the value of total solids determined. Results: for the oxidation index, concentrations of 250 µg/mL were sufficient to decolorize the permanganate solution in the same period of time as the quercetin standard. However, the IC50 calculated for the reducing power, the inhibition of the DPPH radical and ABTS were higher than the ascorbic acid standard with values of 362.33; 190.34 and 241.88 µg/mL, respectively. Conclusions: the extract of leaves of Spondias mombin L. in 70% ethanol presents a high antioxidant action in the six experimental models tested, even though in most cases, with lower values than the reference substance used. These results, together with the structural diversity of metabolites present in it, highlight its value as a potential natural antioxidant.Introducción: la especie Spondias mombin L. es una planta que crece en Cuba y a la que se le reporta un número considerables de aplicaciones etnofarmacológicas y elevado poder antioxidante. Sin embargo, la mayor parte de estos reportes está orientada al fruto, el cual resalta por su valor nutricional. Objetivo: evaluar la actividad antioxidante de un extracto de hojas de Spondias mombin L. en etanol al 70 %. Método: la actividad antioxidante fue evaluada por seis métodos diferentes: determinación del índice de oxidación, poder reductor, inhibición de los radicales DPPH y ABTS, capacidad reductora del peróxido de hidrógeno y capacidad de neutralización del radical oxígeno. Se evaluaron concentraciones desde los 1 000 hasta los 62,5 µg/mL preparadas a partir del valor de sólidos totales determinados. Resultados: para el índice de oxidación, concentraciones de 250 µg/mL resultaron suficientes para decolorar la solución de permanganato en igual período de tiempo que el patrón de quercetina. Sin embargo, los IC50 calculados para el poder reductor, la inhibición del radical DPPH y del ABTS resultaron mayores que el estándar de ácido ascórbico con valores de 362,33; 190,34 y 241,88 µg/mL, respectivamente. Conclusiones: el extracto de hojas de Spondias mombin L. en etanol al 70 % presenta una elevada acción antioxidante en los seis modelos experimentales ensayados, aun cuando en la mayor parte de casos, con valores inferiores al de la sustancia de referencia empleada. Estos resultados conjuntamente con la diversidad estructural de metabolitos presentes en el mismo resaltan su valor como potencial antioxidante natural.Introdução: a espécie Spondias mombin L. é uma planta que cresce em Cuba e à qual são relatados um número considerável de aplicações etnofarmacológicas e alto poder antioxidante. No entanto, a maioria desses relatos é voltada para o fruto, que se destaca pelo seu valor nutricional. Objetivo: avaliar a atividade antioxidante de um extrato de folhas de Spondias mombin L. em etanol 70%. Método: a atividade antioxidante foi avaliada por seis diferentes métodos: determinação do índice de oxidação, poder redutor, inibição dos radicais DPPH e ABTS, capacidade redutora do peróxido de hidrogênio e capacidade de neutralização do radical oxigênio. Foram avaliadas concentrações de 1000 a 62,5 µg/mL, preparadas a partir do valor de sólidos totais determinado. Resultados: para o índice de oxidação, concentrações de 250 µg/mL foram suficientes para descolorir a solução de permanganato no mesmo período de tempo do padrão de quercetina. No entanto, o IC50 calculado para o poder redutor, a inibição do radical DPPH e ABTS foram superiores ao padrão de ácido ascórbico com valores de 362,33; 190,34 e 241,88 µg/mL, respectivamente. Conclusões: o extrato de folhas de Spondias mombin L. em etanol 70% apresenta alta ação antioxidante nos seis modelos experimentais testados, embora na maioria dos casos com valores inferiores à substância de referência utilizada. Esses resultados, juntamente com a diversidade estrutural de metabólitos presentes nele, destacam seu valor como potencial antioxidante natural

DESARROLLO DE COMPETENCIAS PROFESIONALES EN LA PRÁCTICA DE LABORATORIO DE FISIOLOGÍA DE LOS SISTEMAS VEGETATIVOS A TRAVÉS DE LA REDACCIÓN DE ARTÍCULOS CIENTÍFICOS

Los nuevos retos en la Enseñanza Superior, encaminados a la formación de profesionales competentes dentro de un perfil amplio de desempeño laboral, han revolucionado la manera de pensar y enseñar en la pedagogía contemporánea. Encaminado en esta tendencia educativa, el objetivo del presente trabajo consiste en desarrollar competencias profesionales en los estudiantes universitarios de 4to año de Biología en las prácticas de laboratorio de Fisiología de los Sistemas Vegetativos. En este trabajo se presenta la concepción metodológica de las Prácticas de Laboratorio que concibe la redacción de un artículo científico como variante de informe final de esta actividad docente. Se observó y evaluó, a través del desarrollo de la práctica y la redacción de artículos, la formación académica e investigativa del estudiante, la discusión del análisis científico de los contenidos abordados en clases y el desarrollo de habilidades investigativas y de trabajo en el laboratorio, que lograron establecer relaciones interdisciplinarias; permitiéndole explorar, caracterizar, integrar, aplicar, desarrollar habilidades e inquietudes investigativas y formarse como un profesional competente con una visión generalizadora de la carrera.PALABRAS CLAVE: competencias profesionales; práctica de laboratorio; interdisciplinariedad; redacción científicaTHE DEVELOPMENT OF PROFESSIONAL COMPETENCES IN LABORATORY WORK OF PHYSIOLOGY OF THE VEGETATIVE SYSTEMS THROUGH THE WRITING OF SCIENTIFIC ARTICLESABSTRACTNowadays, the new challenges in the Higher Education have changed vigorously the way of thinking and teaching in contemporary pedagogy in order to form students with professional competences and capable of solving scientific problems inside a wide profile of labor performance. The main goal for this work is to develop professional competences in students during the lab work in Physiology of Vegetative Systems in 4th year of the degree course of Biology. In this article there is proposed a methodological conception of Laboratory Work that conceives the writing of a scientific article as variant of final report. It was observed and evaluated, through the progress of the lab work and the writing of scientific articles, the academic and research training of the students, the improving and discussion of the scientific analysis of the contents tackled in classes and the development of research and laboratory work skills, establishing interdisciplinary relations through the solution of professional problems in such a way that allows students to explore, characterize, integrate, apply, develop skills and research concerns to form them like a competent professional with a generalizing vision of the degree course.KEYWORDS: professional competences; laboratory work; interdisciplinary; scientific writing</p

Effects of Persea americana Mill. seed extracts on the postembryonic development of Musca domestica (Diptera: Muscoide)

Context: The synthetic insecticides used to control Diptera are harmful to the environment and humans. Extracts and compounds from plants are a more sustainable source for the development of bio-insecticides. Aims: To evaluate the efficacy of a hydroalcoholic extract of Persea americana Mill seeds as an alternative control of the species Musca domestica. Methods: The extracts were obtained by two methods, the Shaker (S) and the Soxhlet extraction (SE) method, using 94% ethanol as the solvent. Also, the qualitative chemical composition was determined by phytochemical screening. The effect of the two extracts on the post-embryonic development of the fly as well as the adulticidal effect was evaluated. Results: Phytochemical analysis revealed the presence of metabolites such as alkaloids, coumarins, tannins, flavonoids, sugars and amino acids. The influence on the post-embryonic development of M. domestica was demonstrated, especially on the viability of larvae and neolarvae to adults; however, the effect on the weight and duration of each period was low. The adulticidal effects of the extracts were determined by the lethal concentration 50(LC50) of 2.910 mg/100 mL and 3.944 mg/100 mL for the S and SE extracts, respectively. Conclusions: Both extracts showed their insecticidal effects against Musca domestica, but the extract elaborated by S method showed greater influence diminishing viability and better adulticidal effect

A Two-Step Purification Procedure of Phospholipases A2 from the Sea Anemone Condylactis gigantea

Submitted by EMERSON LEAL ([email protected]) on 2019-06-12T19:28:42Z No. of bitstreams: 1 Protocolo de purificación en dos etapas de fosfolipasas A2 a partir de la anémona marina Condylactis gigantea.pdf: 978834 bytes, checksum: 57fa15e40656a2df50e09018fe03ace6 (MD5)Approved for entry into archive by EMERSON LEAL ([email protected]) on 2019-06-12T20:08:42Z (GMT) No. of bitstreams: 1 Protocolo de purificación en dos etapas de fosfolipasas A2 a partir de la anémona marina Condylactis gigantea.pdf: 978834 bytes, checksum: 57fa15e40656a2df50e09018fe03ace6 (MD5)Made available in DSpace on 2019-06-12T20:08:42Z (GMT). No. of bitstreams: 1 Protocolo de purificación en dos etapas de fosfolipasas A2 a partir de la anémona marina Condylactis gigantea.pdf: 978834 bytes, checksum: 57fa15e40656a2df50e09018fe03ace6 (MD5) Previous issue date: 2017Universidad de Oriente. Facultad de Ciencias Naturales. Santiago de Cuba, Cuba.Universidad de La Habana. Facultad de Biología. Centro de Estudio de Proteínas. Ciudad Habana, Cuba.Instituto de Catálisis y Petroleoquímica. Madrid, España.Universidad de La Habana. Facultad de Biología. Centro de Estudio de Proteínas. Ciudad Habana, Cuba.Universidad de La Habana. Facultad de Biología. Centro de Estudio de Proteínas. Ciudad Habana, Cuba.Fundação Oswaldo Cruz. Centro de Estudos de Biomoléculas Aplicadas à Saúde. Universidade Federal de Rondônia. Departamento de Medicina. Porto Velho, RO, Brasil.Universidad de La Habana. Facultad de Biología. Centro de Estudio de Proteínas. Ciudad Habana, Cuba.El veneno de los celenterados marinos constituyen mezclas complejas de varios componentes, muchos de naturaleza proteica, y para los cuales se ha descrito la actividad fosfolipásica A2. El objetivo de la presente investigación fue purificar las fosfolipasas A2 (FLA2) procedentes de la anémona marina Condylactis gigantea a partir de un protocolo de dos etapas para su posterior caracterización. Se muestra la purificación de FLA2 en un soporte cromatográfico de afinidad con fosfatidilcolina de huevo inmovilizada covalentemente para la purificación de fosfolipasas A2, a los que se les comprobó cualitativamente la actividad fosfolipásica A2 por cromatografía en placa (TLC) utilizando sustrato marcado con fluorescencia. Dicho soporte cromatográfico permite que en un protocolo de purificación de solamente dos pasos se obtengan tres componentes proteicos de pesos moleculares entre 18000 y 14000, con al menos un componente que posee actividad fosfolipásica A2.Marine coelenterate venom is composed of complex mixtures of several substances, mainly of proteins, for which phospholipase A2 activity has been described. This research study aims to test a two-step purification procedure for phospholipases A2 (PLA2) to filter enzymes for further characterization. PLA2 purification from the sea anemone Condylactis gigantean is conducted through a chromatographic affinity support MANA - Sepharose CL 4B with covalently immobilized phosphatidylcholine egg. The phospholipase A2 activity was corroborated by using qualitative TLC and a fluorogenic substrate. By means of the above-mentioned support, purification of three protein-based components can be carried out. These components are produced with molecular weights between 18000 and 14000, and at least one component possessing phospholipase A2 activity

LC-MS Characterization and Biological Activities of Cuban Cultivars of Plectranthus neochilus Schltr

Plectranthus neochilus Schltr. (Lamiaceae) is a plant recently introduced in Cuba. Worldwide, it is an ethnomedicinal alternative for its use against microbial infections, but the Cuban population use the extracts to treat sleep disorders. To address this apparent incongruity, four collections (from different seasonal conditions in the year) of Cuban P. neochilus cultivars were analyzed in terms of their pharmacognostic characteristics. Three extracts using fresh and dried leaves were chemically and biologically characterized. UPLC-DAD-MS/MS analysis was performed to determine their chemical composition, while a panel of nine microorganisms was used to evaluate their antimicrobial activity. Finally, cytotoxic effects of different fractions were measured in three cell lines by the resazurin viability assay. In contrast to previously reported micro and macromorphological properties of P. neochilus, the leaves from the Cuban cultivars did not present glandular trichomes, nor did they produce quantifiable levels of essential oils. Moreover, aqueous extracts used by the population revealed no significant antimicrobial activity and were not cytotoxic. The three extracts showed a similar phytochemical composition, i.e., eight flavonoids, seven abietane diterpenes, and rosmarinic acid as the major constituent, most of them reported for the first time in this species. The low yield of essential oil, the absence of glandular trichomes, compounds with a high level of oxidation, and a moderate antimicrobial activity detected were the most distinctive pharmacognostic and biological characteristics of P. neochilus grown in Cuba. These aspects could explain its non-use as an antimicrobial

LC-MS characterization and biological activities of Cuban cultivars of Plectranthus neochilus Schltr

Plectranthus neochilus Schltr. (Lamiaceae) is a plant recently introduced in Cuba. Worldwide, it is an ethnomedicinal alternative for its use against microbial infections, but the Cuban population use the extracts to treat sleep disorders. To address this apparent incongruity, four collections (from different seasonal conditions in the year) of Cuban P. neochilus cultivars were analyzed in terms of their pharmacognostic characteristics. Three extracts using fresh and dried leaves were chemically and biologically characterized. UPLC-DAD-MS/MS analysis was performed to determine their chemical composition, while a panel of nine microorganisms was used to evaluate their antimicrobial activity. Finally, cytotoxic effects of different fractions were measured in three cell lines by the resazurin viability assay. In contrast to previously reported micro and macromorphological properties of P. neochilus, the leaves from the Cuban cultivars did not present glandular trichomes, nor did they produce quantifiable levels of essential oils. Moreover, aqueous extracts used by the population revealed no significant antimicrobial activity and were not cytotoxic. The three extracts showed a similar phytochemical composition, i.e., eight flavonoids, seven abietane diterpenes, and rosmarinic acid as the major constituent, most of them reported for the first time in this species. The low yield of essential oil, the absence of glandular trichomes, compounds with a high level of oxidation, and a moderate antimicrobial activity detected were the most distinctive pharmacognostic and biological characteristics of P. neochilus grown in Cuba. These aspects could explain its non-use as an antimicrobial

Preparation of non-toxic nano-emulsions based on a classical and promising Brazilian plant species through a low-energy concept

A true sustainable and ecofriendly concept of utilization of natural products must involve not only the obtainment of plant material in consonance with biodiversity preservation, but also the potential lower risk to the environment and lower consume of energy in the transformation of the plant into novel products. We therefore describe an elegant study in which the fruits of Pterodon emarginatus, a high promising Brazilian species that can be obtained through a sustainable use of biodiversity, are the natural raw material for the preparation of nano-emulsions. The essential oil was prepared by hydrodistillation, using a classical extraction with a non-toxic solvent instead of organic solvents. Moreover, the utilization of low energy emulsification method at room temperature and rational design with blends of non-ionic surfactants allowed the preparation of nano-emulsions with desirable properties. An optimal nano-emulsion with droplet size around 110−130 nm, low polydispersity index (around 0.14 – 0.20) and high kinetic stability was obtained. The process of preparation of this nano-emulsion was reproducible and it presented stability towards temperature (from 25 Cº to 80 Cº) and also long-term physical stability for 540 days in storage. Moreover, toxicity in vitro assays were also performed in order to evaluate the potential risks of the optimal nano-emulsion. The results showed that it could be considered non-irritant. Therefore, the present study shows the feasibility of classical concepts of nano-emulsion stabilization to generate a novel nano-emulsion with desirable properties.The authors would like to thank the Coordination for the Improvement of Higher Education Personnel (CAPES) by the doctorate grant to the first author and the Pro-Rectory of Cooperation and Inter-institutional Relations of the Federal University of Amapá (UNIFAP) by the financial support which allowed the international mobility carried out by the last author. We also would like to thank the Pro-Rectory of Inter-Institutional Relations (International Mobility Program) and Pro-Rectory of Post-Graduation (Papesq Program) of the Federal University of Amapá), for the financial support.Peer reviewe