bluuebunny/crossref_metadata_2025 huggingface dataset:
Tres momentos de institucionalización de la educación de anormales en Colombia: análisis desde las políticas educativas
Authors: Orjuela Sánchez Gloria Janneth
Published: October 2018

Se pretende mostrar aquí una primera forma de acercamiento a la noción de diferencia desde las políticas educativas, con lo que se pretende evidenciar los momentos que han tenido estas políticas, en relación con las formas de institucionalización de la educación para la diferencia en Colombia. En esa línea de ideas, cabe anotar que se hará uso de la historia como instrumento que permitirá analizar la política, sus reformas, sus efectos y la relación de ésta con la noción de diferencia. Así mismo, es la historia la que posibilitará poner en diálogo reflexiones acerca de la inclusión y la educación de la diferencia.
Estado del arte de la investigación “inclusión del componente pedagógico, desde lo crítico, en los principios de la ética de mínimos y máximos de Adela Cortina en la categoría ciudadanía”
Authors: Hernández Acevedo Álvaro
Published: October 2018

Este trabajo muestra una aproximación al estado del arte de la investigación acerca de la formación en ciudadanía, partiendo de la inclusión del componente pedagógico, desde lo crítico, a las distintas formas políticas educativas de ser y generar ciudadanos de y para el mundo. Se parte de la comprensión de las múltiples acepciones que se han venido estableciendo acerca de ciudadanía, su relación con las dimensiones humanas, especialmente lo político, económico, social y cultural. En este contexto, se plantea la función de la pedagogía en el cómo, qué y para qué integrar el aula, las experiencias vitales y la teoría que incluyen el ser ciudadano, además que las relaciones que se establecen para lograr una mentalidad ciudadana, crítica y emancipadora de los sistemas hegemónicos.
Estrategias pedagógicas que favorecen el aprendizaje de niñas y niños de 0 a 6 años de edad en Villavicencio- Colombia
Authors: Cortés Alexandra , Garcia Giovanna
Published: October 2018

La educación en los primeros años vida de es un proceso continuo e integral, producto de múltiples experiencias que brinda la escuela a los niños y niñas, a través de la interacción con la sociedad y con el medio ambiente, siendo la base de la formación integral del ser humano. Unas de las tantas herramientas o estrategias pedagógicas son el juego, las artes escénicas, la pintura y la lectura, las cuales se transforman en estrategias lúdico-pedagógicas que favorecen el desarrollo integral del niño. Esta revisión bibliográfica tiene como objetivo presentar los resultados de diversas investigaciones que contienen pluralidad de herramientas metodológicas, que los docentes pueden emplear en el aula de clase, para desarrollar en el niño un mejor aprendizaje. Se encuentra que existe una variedad de estrategias implementadas por los maestros en las instituciones educativas; sin embargo, no se encuentra una investigación que produzca e integre las diferentes herramientas pedagógicas que orienten a los agentes educativos, para favorecer el proceso de aprendizaje en los niños de 0 a 6 años de edad, como es el caso de la ciudad de Villavicencio, en donde se puede establecer que no se cuenta con algún tipo de investigación que plantee dichas herramientas.
Percepción de los niveles personal, familiar, educativo, social y afectivo en internos de la penitenciaria de Acacias, Meta
Authors: Ballen Fernanda , Reyes Ana María , Rodríguez Francy
Published: October 2018

En este artículo se presentan los resultados de la investigación realizada en la penitenciaría de Acacías – Meta, con la cual se pretendió conocer, identificar y describir la percepción de los internos del pabellón 4 de dicho penal, sobre los niveles personal, familiar, educativo, social y afectivo de acuerdo a los sistemas del modelo ecológico. Para comenzar, la teoría del modelo ecológico postulada por Brofenbrenner, consiste en el estudio científico de la progresiva acomodación mutua, entre un ser humano activo en desarrollo y las propiedades cambiantes de los entornos inmediatos en los que vive la persona (sistemas) (1987, p. 40), lo cual es la “interrelación de diferentes elementos ya sean objetos, situaciones o elementos, procesos, variables, de manera organizada los cuales siempre tienen determinada función” (p. 7). De esta manera, la situación de encarcelamiento es una experiencia difícil de asimilar para la persona privada de la libertad y sus familias, al menos en los primeros momentos del ingreso en prisión, la cual genera en estas personas un esfuerzo adaptativo constante que, como consecuencia, le genera una serie de distorsiones afectivas, emocionales, cognitivas y perceptivas (Altamirano, 2013), puesto que existen restricciones, como el aislamiento emocional y la consecuente frustración (Arroyo, 2011); así mismo existen factores que impactan en el individuo, y los cuales se encuentran asociados a la misma condición de internamiento,  como la privación de libertad, el alejamiento de las redes sociales y familiares, el abandono de la vida laboral, estrés cognitivo asociado a las preocupaciones por la situación de la familia, el hacinamiento, la falta de privacidad, entre otros (Ruiz, 1999). Se tiene por objetivo general conocer la percepción de los internos del pabellón 4 de la penitenciaria de Acacias- Meta sobre los niveles de los sistemas del modelo ecológico (familiar, educativo, social y afectivo). En cuanto a la metodología realizada fue de enfoque cualitativo, diseño fenomenológico, una muestra de 22 internos del pabellón 4 entre las edades de 19 a 44 años; para la recolección de datos se aplicó una entrevista a profundidad.Por último, se realizó el análisis de información por medio del programa Atlas Ti, el cual es una herramienta flexible que permite analizar varias vertientes y por lo tanto facilita en gran parte la organización, manejo e interpretación de datos cualitativos (Cuevas y Méndez, 2012).
Comunidad de aprendizaje con el uso de MOOC sobre CSC en la formación permanente de profesores
Authors: Beltrán Penagos María Alejandra , Martínez Pérez Leonardo Fabio , Ramírez Martínez Jorge Enrique
Published: October 2018

Se presenta la sistematización de la experiencia piloto de un MOOC en el que participaron 38 profesores en diferentes niveles de formación con el fin de que aborden las Cuestiones Sociocientíficas (CSC) como estrategia didáctica en sus prácticas pedagógicas. La sistematización se desarrolla según los planteamientos de Mejía (2012), haciendo una categorización de cinco aspectos de análisis transversales: práctica pedagógica/actualización profesional; estrategias/recursos de enseñanza-aprendizaje; abordaje de CSC; contexto/cotidianidad; y formación ciudadana. Para la discusión de los resultados, se parte de la interpretación de la información elaborada por los profesores participantes durante el desarrollo del MOOC y del conocimiento de la literatura que se trae a la indagación. Se encontraron debilidades en cuanto a la plataforma, a las habilidades tecnológicas, a la autonomía, a la comunicación profesor-estudiante, y a la evaluación. Las oportunidades analizadas se refieren a los espacios virtuales para la enseñanza-aprendizaje y a los momentos de participación. En cuanto a las fortalezas, se evidenciaron respecto a un escenario virtual, a la secuencialidad y al rol de los estudiantes. Finalmente, se analizan algunas de las amenazas de la experiencia a nivel general en cuanto a la adaptación a una sociedad en red y al uso de las redes sociales en educación.
¿Cómo el interés y la motivación influyen en el aprendizaje de una lengua extranjera?
Authors: Bilbao Clara Esperanza
Published: October 2018

Aprender una lengua extranjera puede ser para algunas personas una experiencia interesante, fácil y productiva pero para otras; aburridora, complicada e incluso inútil. Sin embargo, es un hecho que en la mayoría de los casos, independientemente de la percepción que se tenga, el estudiante no alcanza la misma competencia en la lengua extranjera que en la lengua materna. Aunque este hecho se puede explicar a través de factores específicos al proceso de adquisición de la lengua (los cuales son muy decisivos), también podemos hallar respuesta en factores relacionados con el entorno del estudiante, que determinan desde el momento en que se aprende la lengua, ciertas actitudes y motivación que favorecerán o no la adquisición y el posterior nivel de competencia en ésta.
La Argumentación Como Estrategia Que Potencie El Pensamiento Crítico En Los Estudiantes De Grado 5° Del Centro Educativo Castilleral
Authors: Alean Jiménez Ana Milena , Babilonia Herrera Elvira , Ramírez Parra Carlos Fernando
Published: October 2018

La argumentación es una de las características del pensamiento crítico, por tanto, de mucha importancia para su adquisición; ante esta importancia, surgen diversas investigaciones, sin embargo pocos estudios han abordado directamente los niveles argumentativos; es por ello que esta investigación busca en sus objetivos: Analizar los niveles argumentativos en el desarrollo del pensamiento crítico de los estudiantes de 5° del Centro educativo (CE) Castilleral al discutir sobre problemas socialmente relevantes. Para ello, pretende diseñar y aplicar una UD, basada en resolución de problemas socialmente relevantes; Evaluar los niveles argumentativos de los estudiantes al inicio y al final de aplicación de la Unidad Didáctica (UD), estableciendo evolución conceptual e identificando los obstáculos presentados en la argumentación como estrategia para potenciar el pensamiento crítico. El cumplimiento de estos objetivos permitirá identificar los niveles argumentativos y la evolución conceptual de los estudiantes, cuando se enfrentan a un problema socialmente vivo; haciendo uso del enfoque cualitativo, específicamente del diseño de estudio de casos. Los instrumentos utilizados se remiten a un test de ideas previas, (pre y pos test), además de la aplicación de una UD que permite la recolección de información. Los resultados arrojan el surgimiento de un nivel emergente (Nivel 0), que demuestra dificultad para describir e interpretar, ausencia de los niveles 3, 4 y 5 planteados por Erduran; que se refieren a plantear justificaciones, usos de cualificadores o respaldo teórico y contraargumentos. De igual forma, se evidencia cambio conceptual, en cuanto hay un mayor acercamiento al saber científico. Por otro lado, se vio un ligero aumento en el uso de las conclusiones (Nivel 2), lo que refleja avances en los niveles argumentativos. Esto lleva a concluir que el abordaje de temas socialmente relevantes y la pertinencia en el diseño de la investigación (pre-UD- post) en el aula, contribuyen con la evolución conceptual y avances en los niveles argumentativos de los estudiantes.
Desarrollo de habilidades de comprensión lectora en inglés –como lengua extranjera- en estudiantes de quinto de primaria
Authors: Guarín Ramírez Maria del Carmen , Ramírez Rojas María Isabel
Published: October 2018

En el presente artículo se describe el proceso investigativo cuyo objetivo fue desarrollar habilidades de comprensión lectora en inglés –como lengua extranjera- en estudiantes de grado quinto, de una institución pública del municipio de Cartago, Valle del Cauca. Este se abordó bajo el modelo de lectura interactiva, que concibe la comprensión textual como un proceso de interacción entre el lector y el texto, se fundamentó la propuesta desde los aportes de Solé (1998); Jouini (2005); Van Dikj & Kintsch (1983); Cummins (1983) y Anderson (1984), entre otros. El tipo de estudio fue cualitativo donde a través del enfoque de estudio de caso se analizó cómo los estudiantes desarrollaban las habilidades de lectura comprensiva en inglés. El instrumento de análisis fue una unidad didáctica titulada -Healthy Food compuesta por un instrumento de ideas previas aplicado como pre test y post test y cuatro secuencias que contenían ocho cuestionarios que sustentaron el análisis de la información.
Representaciones sociales de estudiantes universitarios sobre el papel de la universidad en la creación de cultura de paz
Authors: Urbina Cárdenas Jesús Ernesto , Ovalles Rodríguez Gustavo Adolfo , Pérez Fernández Blanca Johanna
Published: October 2018

El artículo muestra los resultados de la investigación sobre el tipo de representaciones sociales que poseen los estudiantes de la UFPS, acerca del papel de la universidad en la creación de una cultura de paz. Las categorías centrales sobre las cuales se fundamenta son las siguientes: la teoría de las representaciones sociales (RS)5 como marco teóricoepistemológico para la interpretación de los fenómenos socio-educativos y el concepto de Cultura de Paz. El texto expone la parte descriptiva del estudio, a partir de una encuesta aplicada a quinientos (500) estudiantes de las distintas carreras de la universidad. Algunos de los resultados permiten percibir cierto escepticismo frente al proceso de paz y una falta de conocimiento sobre los avances y logros de los diálogos de La Habana. El 59.9% afirma no conocer lo que se está pactando en la isla, el 37.4% cree que nunca se va a firmar la paz, el conflicto armado se asocia con la inequidad social en un 54% de las respuestas, la palabra con la que asocian la paz, en mayor porcentaje, es “la justicia” en un 34.8%, el 45.3% considera que la universidad debe abrir debates permanentes como principal estrategia para construir cultura de paz, y el 57.7% afirma que no hay un buen ambiente en la universidad para construir dicha cultura.
La experiencia de confianza de los niños en proceso de educación musical: una relación del cuidado
Authors: Quintero Jurado Jessica Marcela
Published: October 2018

Esta investigación tuvo como objetivo comprender las experiencias de confianza, como sentimiento moral, en el proceso de educación musical de niños y niñas entre 9 y 11 años de la Escuela Musical Amadeus de la ciudad de Medellín. Se adoptó el método fenomenológico-hermenéutico. Para la selección de los participantes se realizó un muestreo por fases. Las técnicas que se utilizaron fueron fotohistoria, fotolenguaje, entrevista en profundidad y grupo focal como estrategia de triangulación. Se encontró que la relación de confianza posee unas características que la consolidan como una relación de cuidado, pues posibilita el aprendizaje y el acceso a nuevas experiencias, promueve y facilita la regulación emocional, es considerada por los niños y las niñas como una relación empática y comprensiva, y está asociada a una expectativa de incondicionalidad.
Unidades didácticas y desarrollo de habilidades comunicativas en el aula
Authors: Reinoso Gómez Mario Fernando
Published: October 2018

Este artículo se basa en el trabajo de investigación que está orientado hacia el fortalecimiento de las habilidades comunicativas en los estudiantes del grado noveno de una institución educativa pública del municipio de Bucaramanga. Para ello se planteó la preparación y ejecución de unidades didácticas que incorporaron actividades de aula que estimularon a los estudiantes en sus procesos comunicativos. Para llevar a cabo este proyecto se tuvo en cuenta la investigación cualitativa desde el enfoque de la investigación-acción ya que el elemento fundamental de la misma es la sociedad, representada en el grupo de estudiantes que son objeto de este estudio. De esta manera, este trabajo se denominó: Unidades didácticas como estrategia para el fortalecimiento de las habilidades comunicativas en los estudiantes del grado noveno de una institución pública del municipio de Bucaramanga.En principio, se pudo establecer que existe una marcada dificultad en los procesos de comprensión de lectura por parte de este grupo de estudiantes. Dicha falencia, se hace evidente en los resultados de las pruebas SABER que, a la par con la prueba diagnóstica de lenguaje, expuso otras dificultades que van más allá de lo que registran las pruebas estandarizadas. Problemas en las habilidades para redactar, sostener argumentos de forma oral y dificultades a la hora de escuchar a sus pares y docentes, se suman a la deficiente comprensión lectora. A raíz de lo anterior, surgió la necesidad de implementar una serie de acciones orientadas a la mejora de las habilidades comunicativas durante (12) meses de implementación y análisis. Este proceso estuvo enmarcado en la formulación de (3) unidades didácticas que integraron el desarrollo de las cuatro habilidades comunicativas (leer, escribir, hablar y escuchar), contando con el enfoque y la orientación de la teoría de desarrollo del lenguaje de Noam Chomsky, puesto que este autor se ha destacado en el estudio y evolución de las destrezas comunicativas a lo largo del desarrollo de procesos formativos en los seres humanos. La reflexión final condujo a establecer que el desarrollo de las unidades didácticas aquí propuestas derivó en una notoria mejoría en los procesos comunicativos de los estudiantes, y a su vez, brindó una nueva perspectiva de la aproximación a los temas desde un modelo dinámico que contó con la participación activa de los implicados y desde ya se proyecta para su ejecución en otros grados y materias.
Manejo de la atribución hostil en el aula a partir del currículo educativo especializado
Authors: Arrubla Sánchez Ricardo
Published: October 2018

El objetivo de esta investigación es la construcción de un modelo educativo para prevenir el comportamiento disocial y delictivo en adolescentes a partir de la teoría de guiones cognitivos de Bandura, y sustentado desde el uso de la razón jurídica y práctica en adolescentes por medio de la incorporación de la cultura de la legalidad en los colegios. Es un estudio descriptivo –  explicativo, realizado con dos grupos focales integrado por estudiantes de grado 11 a quienes se les realizó entrevista semiestructurada, y la aplicación de la Escala de Conducta Antisocial y Delictiva, Cuestionario de Agresión Proactiva-Reactiva -RPQ- "Reactive-Proactive Aggression Questionnaire". En la población en estudio se identificaron conductas relacionadas con la impulsividad, agresividad, búsqueda de sensaciones, y narrativas violentas, generando en los estudiantes el síndrome de atribución hostil, y un déficit en el procesamiento de la información. Como conclusión principal, la modificación estructural de la cognición negativa en los estudiantes se debe llevar a cabo a partir de la creación de un neurocurrículo que facilite la mediatización del significado, tanto en el nivel cognitivo como en el nivel afectivo.
EFFECT OF POLYCAPROLACTONE ON CHARACTERISTICS AND MORPHOLOGY OF ALGINATE/CHITOSAN/LOVASTATINE COMPOSITE FILMS
Authors: Chinh Nguyễn Thúy , Thai Hoang , Thach Loc Thi , Le Giang Duc , Ngo Thuy Phuong
Published: October 2018

In this work, alginate (AG)/chitosan (CS)/lovastatine (LS) AG/CS/PCL/LS composite films using polycaprolactone (PCL)  are prepared by solution method with the ratio of AG/CS and LS content fixed at 4/1 and 10 wt.% (in comparison with the total weight of CS and AG), respectively.  The PCL content is used at 3, 5 and 10 wt.% (in compared with total weight of AG, CS and LS). The role of PCL as a compatibilizer in AG)/CS)/LS composites is considered by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and Differential Scanning Calorimetric (DSC) methods. Based on the change in FTIR spectra, morphology and thermal parameters of AG/CS/PCL/LS composites, it can be seen that PCL has effectiveness of compatibility for AG, CS, and LS as well as plasticity for the composites. Besides, the influence of PCL content on the swelling degree of the composites is also investigated.
Changes in glycosylated flavonoids in soybean (Glycine max (L.) Merr. cv. “Nam Dan”) leaves under aphid infestation
Authors: Thơm Mai Thị , Toàn Trần Ngọc , Thanh Huyền Trần Thị , Chung Mai Văn
Published: October 2018

Changes in contents of glycosylated flavonoids in leaves of soybean (Glycine max (L.) Merr. cv. “Nam Dan”) in the flowering stage under infestation of cowpea aphid (Aphis craccivora Koch) was investigated. A strong decrease in the level of glycosylated flavonoids, e.g., genistein 7-O-glucoside, 2’OH genistein 7-O-glucoside, 2’OH genistein malonyl glucoside, after 48-96 hours post-infestation (hpi) of aphid. Levels of these compounds in aphid-infested leaves were remarkably lower than those in controls. Whereas, genistein and total flavonoids in the aphid-infested leaves were induced to higher contents than that observed in control. Activity of important enzymes regarding biosynthesis of flavonoids such as phenylalanine ammonia-lyase (PAL, EC. 4.3.1.5), chalcone synthase (CHS, EC 2.3.1.74) and chalcone isomerase (CHI, EC 5.5.1.6) in the aphid-infested leaves strongly increased during experiemntal time. An increase in acitivity of those enzymes was proportional with the induced decrease of the glycosylated flavonoids and an accumulated increase of genistein and total flavonoids. These results indicate that, changes in the glycosylated flavonoids occured in soybean “Nam Dan” leaves infested by cowpea aphid may connect to a protective mechanism in this soybean cultivar in the flowering stage.
CHEMICAL CONSTITUENTS OF THE ETHYL ACETATE EXTRACT OF THE FRUIT BODIES OF PHELLINUS GILVUS
Authors: Dang Quang Ngoc
Published: October 2018

Five fungal secondary metabolites named 1,2,4,5-tetrachloro-3,6-dimethoxybenzene (1); ergosterol (2); ergosterol peroxide (3); (E)- 4-(3,4-dihydroxyphenyl)but-3-en-2-one (4) and [Bi-1,4-cyclohexandien-1-yl]-3,3’,6,6’-tetrone, 4, 4’-dihydroxyl-2,2’,5,5’-tetramethyl (5) were purified from ethyl acetate extract of the fruit bodies of Phellinus gilvus collected at Pu Mat national park, Nghe An province. Their structures were charaterized by 1D, 2D NMR and GC-MS spectroscopies. Especially, the structure of compound 1 was confirmed by X-ray crystallographic analysis. The antimicrobial and cytotoxicity activities of compounds 1 were also evaluated. This is the first report on the chemical constituents of Vietnamese Phellinus gilvus.
THE PROTECTIVE EFFECT OF SOME FRACTIONS AND ISOLATED COMPOUNDS FROM EUPHORBIA HIRTA L. ON PANCREATIC β-CELLS MIN6
Authors: Le Bach Thi , Le Dung Tien , Nguyen Tuan Trong , Nguyen Thanh Quoc Chau , Joëlle Quetin Leclercq , Bui Buu Hue Thi
Published: October 2018

Euphorbia hirta L., a kind of herbs belonging to family Euphorbiaceae, has been found a lot in the Mekong Delta. From the ethyl acetat and methanol fractions of this plant, four pure compounds were isolated and identified their chemical structure by spectroscopic techniques including quercitrin (1), luteolin (2), quercetin (3) and caffeic acid (4). The effect of crude ethanolic extract and some fractioned extracts as well as four isolated compounds from E  hirta L., collected in the Mekong Delta, on endoplasmic reticulum stress-induced cell death in mouse β-cell lines was investigated. The results showed that methanol fraction and a isolated compound, quercitrin gave strong cell-protective effect with the cell viability of 69% and 78% at the dose of 100 µg/mL and 10 µg/mL, respectively. This proves that E hirta L. might have anti-diabetic effects and worth conducting further pharmacological investigations related to type 2 diabetes mellitus.
CHOLESTANE-TYPE STEROIDS FROM THE OCTOCORAL Verrucella corona
Authors: Ngoc Ninh Thi , Hanh Tran Thi Hong , Cuong Nguyen Xuan , Thanh Nguyen Van , Thao Do Thi , Nam Nguyen Hoai , Thung Do Cong , Kiem Phan Van , Minh Chau Van
Published: October 2018

Using various chromatographic separations, three cholestane-type steroids were isolated from the methanol extract of the octocoral Verrucella corona. Their structures were elucidated to be (22E)-cholesta-5,22-dien-3β-ol-7-one (1), trans-liagosterol (2), and guggulsterol-II (3), by detailed analysis of the 1D and 2D-NMR data as well as comparison with those reported. Among them, compound 2 showed significant cytotoxicity against eight human cancer cell lines as HepG2, HL-60, KB, LNCaP, LU-1, MCF7, SK-Mel2, and SW480.
HCTN 60-EXTRACTION OF CHONDROITIN SULFATE FROM CHICKEN KEEL CARTILAGE BY COMBINING OF ULTRASOUND TREATMENT AND ALCALASE HYDROLYSIS
Authors: Dao Dong Thi Anh
Published: October 2018

ABSTRACT - HCTN 60 Chondroitin sulfate (CS) is a glycosaminoglycan composed of N-acetyl-D-galactosamine and D-glucuronic acid sulfated at positions 4 or 6 [1, 2], that used in functional food for supporting treatment of arthritis diseases. Chicken keel cartilage from byproduct of the industry of poultry slaughter that contains a major content of CS, can be used in CS production. Our study was undertaken to extract CS from chicken keel cartilage by combining ultrasound treatment and Alcalase hydrolysis. The variables of ultrasound treatment such as dilution ratio, pH, temperature, and time were investigated and optimal conditions were obtained by response surface methodology (RMS) method. Optimal values of ultrasound treatment were derived at pH of 7.5, ratio of material and buffer of 1:10 (wmaterial/v­buffer), the ultrasonic temperature of 50oC and time of 21 minutes. Then conditions of Alcalase hydrolysis processing include enzyme per substances E/S of 4% (v/wpro), with the temperature of 55oC and time of 3 hours were determined. The result of HPLC analysis showed that powder product contained 80.45% CS compound with the average molecular weight ( w) of 159.53kDa by GPC. The yield of researched CS reached to 24.29% of absolute dry material; 62.1% in compared with total carbohydrate of dry material.
MODELING OF ESSENTIAL OIL EXTRACTION PROCESS: APPLICATION FOR ORANGE, POMELO, AND LEMONGRASS
Authors: Nguyen Dang Binh Thanh , Nguyen Trung Dung , Ta Duc Hong
Published: October 2018

ABSTRACT - HCTN - 44In this study, the kinetic models of steam distillation of orange (Citrus Sinensis (L.) Osbeck), pomelo (Citrus grandis L.), and lemongrass (Cymbopogon Citratus) for the recovery of essential oils were developed. The model parameters were estimated based on experimental data and comprehensive kinetic mechanisms of the solid-liquid extraction process. Numerical results showed that, the extraction mechanism of the three materials were best fit to the Patricelli two-stage model in which the diffusion of the oil was followed by the washing step. Moreover, the model parameters obtained from the measured data reflected clearly the nature of the two-stage extraction at which the kinetic rate of the washing step (surface extraction) was higher than that of in-tissue diffusion step. Thus, the kinetics of the extraction processes obtained from the present work could be used for the scale-up of the extraction process operating at a large scale and for the purpose of process control as well.
FURTHER STUDY ON CHEMICAL CONSTITUENTS FROM THE HEARTWOOD OF DALBERGIA TON
Authors: Cuong To Dao , Nhan Ngu Truong , Nguyen Nguyen Phuong Dai , Khanh Pham Ngoc , Huong Tran Thu , Cuong Nguyen Manh
Published: October 2018

From the methanol extract of the heartwood of Dalbergia tonkinensis Prain collected in Buon Ma Thuot city, DakLak province, five flavonoids, liquiritigenin (1), 7,3',5'-trihydroxyflavanone (2), sativanone (3), 3'-O-methylviolanone (4) and sulfuretin (5) were isolated. The chemical structures of isolated compounds were determined by the interpretation of NMR spectral data as well as comparison with data from the literature. This study marks that 7,3',5'-trihydroxyflavanone (2) was isolated from the genus Dalbergia for the first time.
METHOXYFLAVONES FROM ORTHOSIPHON STAMINEUS BENTH. AND THEIR PTP1B INHIBITORY ACTIVITIES
Authors: Nguyen Phi Hung
Published: October 2018

Phytochemical analysis of the methanol extract of the aerial parts of Orthosiphon stamineus Benth. led to the isolation of four flavone compounds including 5-hydroxy-3,7,3′,4′-tetramethoxyflavone (1), 3,5,7,3′,4′-pentamethoxyflavone (2), 3,3′-dihydroxy-5,7,4′-trimethoxyflavone (3), and 3,5,3′-trihydroxy-7,4ʹ-dimethoxyflavone (4). Their chemical structures were determined from the spectroscopic evidences, including 1D-NMR and MS, respectively. The inhibitory effects of the isolates (1‒4) against protein tyrosine phosphatase 1B (PTP1B) enzyme were investigated in vitro using ursolic acid as positive control. Among the isolates, compound 4 exhibited potential activity with IC50 value of 10.12 ± 0.19 μM, the others showed weak activity. In this assay, ursolic acid displayed an IC50 value of 3.42 ± 0.25 μM. This is indicated that 3,3′-dihydroxy-5,7,4′-trimethoxyflavone (4) maybe useful for discovery of PTP1B inhibitors as antidiabetic agent.
EXTRACTION OF POLYSACCHARIDES FROM LINGZHI BY ULTRASONIC-ASSISTED ENZYMATIC METHOD
Authors: Hoa Tran Quoc
Published: October 2018

The medicinal values of polysaccharides (PS) in Lingzhi have been shown to lie in many anti-cancer effects and good benefits for human health. Lingzhi, which is rich in healthy PS, has been used more and more commonly in Vietnam in recent years. In the present work, ultrasonic-assisted enzymatic extraction (UAEE) was used for extraction of PS from Lingzhi. The experiments were conducted according to a Box-Behnken design (BBD), with four independent variables: solvent temperature, ultrasonic power, pH, and ultrasonic irradiation time. The results showed that the best adequate extraction conditions were extraction time of 144 min, extraction temperature of 55°C, ultrasonic power of 240W, pH 7.9, and ultrasonic irradiation time of 144 min. Under these conditions, the predicted optimal yield was 3.716%. Whereas by following the optimized conditions, the experimental yield of PS was 3.65% ± 0.14, which was in good agreement with that of the prediction. Compared to the hot water extraction (HWE) method, ultrasonic-assisted extraction (UAE) method and enzyme-assisted extraction (EAE) method, the yield of PS obtained by UAEE was favorable. The PS yield obtained by HWE, and EAE were 1.96% and 3.10%, respectively. These results demonstrated that UAEE was an appropriate and effective extraction of polysaccharides from Lingzhi.
INSULIN-MIMETIC BIFLAVONOIDS FROM A VIETNAMESE MEDICINAL PLANT SELAGINELLA TAMARISCINA
Authors: Phi Hung Nguyen
Published: October 2018

During the search for antidiabetic agents from natural sources, four biflavonoids including amentoflavone (1), robustaflavone (2), cupressuflavone (3), and 3,8′′-biapogenin (4) have been isolated and structurally elucidated from the methanol extract of a Vietnamese medicinal plant Selaginella tamariscina by using combined chromatographic and spectroscopic experiments. All isolated compounds showed significant stimulatory effects on 2-NBDG glucose uptake in 3T3-L1 adipocyte cells. At a concentration of 10 μM, compounds 3 and 4 exhibited potential stimulatory effects by 1.47 and 1.44 fold of inductions as compared with the control (DMSO), respectively. In this assay, the positive control (insulin) showed an induction of 1.54 fold at a concentration of 100 nM. The result suggests that these biflavonoids maybe potential as insulin mimetics for developing antidiabetic agents.
FLAVONOIDS FROM THE LEAVES OF ARALIA HIEPIANA
Authors: Phan Nguyễn Hữu Toàn , Thuần Nguyễn Thị Diệu , Hiền Nguyễn Thị Thu , Hảo Trần Minh , Huyến Phạm Văn
Published: October 2018

Aralia hiepiana J.Wen & Lowry (Araliaceae), a new species from southern Vietnam, is described and illustrated by J. Wen & Lowry in 2002. Up to now, there are not any chemical data from this endemic species. By various chromatography methods, four flavonoids compounds namely kaempferol 3,7-O-α-L-dirhamnopyranoside (1), kaempferol 3-O-β-D-glucopyranosyl-7-O-a-L-rhamnopyranoside (2), kaempferol (3), quercetin (4), apigenin 7-O-β-glucopyranoside (5) were isolated from the methanol extract of leaves of Aralia hiepiana collected in Da Lat, Lam Dong province. Their structures were elucidated using 1-D and 2-D NMR techniques and by comparison with the literature data. This is the first time to isolate these compounds from Aralia hiepiana.
RESEARCH ON THE COMPONENT OF LIPID CLASSES, FATTY ACID, AMINO ACIDS FROM EGG AND BODY OF SEA URCHIN TRIPNEUSTES GRATILLA (LINNAEUS, 1758)
Authors: Dinh Kim Hoa Thi
Published: October 2018

ABSTRACT – HCTN 06The Sea urchin Tripneustes gratilla (Linnaeus, 1758) is a famous species of invertebrate member of the phylum Echinodermata of marine animals living in shallow tropical water. In Viet Nam, it is usually called by the name of yellow sea urchin. This species is mentioned much about its economic and commerce properties. Recently, many researchers have been paying attention to sea urchin because of its positive effect on human health. In terms of medicine and nutrition, the egg of yellow sea urchin was rich in Polyunsaturated Fatty Acids (PUFAs) and essential amino acids. In this research, we focused on determining the total lipid contents, the components of lipid classes and the compositions and contents of fatty acids, amino acids from the body and the egg of the yellow sea urchin T. gratilla (Linnaeus, 1758) collected in Hon Tam, Nha Trang, Khanh Hoa, Viet Nam in 2016. Although the yellow sea urchin T. gratilla has low percentage of total lipid in fresh weigh basis, they are full of essential lipid ingredients such as Wax and Hydrocabon (H + W), Triacylglycerol (TG), Monodiacylglycerol MDAG, Free Fatty Acid (FFA), sterol (ST), and Polar Lipid (PL). In both egg and body samples palmitic acid (16:0) was the most abundant fatty acid with the proportion of about 25%. In addition, arachidonic acid (20:4n-6) is dominent Omega-6 fatty acid in the Monounsaturated Fatty Acid group (MUFA). Furthermore, the research result also showed the very high percentages of omega-3 fatty acids in the egg and body of T. gratilla, with the total contents of 13.97% and 20.67% respectively, especially the presence of eicosapentaenoic fatty acid (C20:5n-3, EPA), a very valuable fatty acid. By the HPLC method, the research also found 17 amino acids in the egg and body of T. gratilla with the existence of 7 essential amino acids.Keywords: Tripneustes gratilla, lipid classes, yellow sea urchin, echinodermata, fatty acid content.
COMPARATIVE STUDY ON VOLATILE COMPOUNDS OF AGARWOOD FROM KHANH HOA PROVINCE EXTRACTED BY DIFFERENT METHODS
Authors: Thuy DINH Thi Thu , Tuyen Tran Thi , Chien Nguyen Quyet , Thuy Tran Thi Thu , Bich Hoang Thi , Toan Tran Quoc
Published: October 2018

Agarwood from Aquilaria crassna cultivated in Khanh Hoa province was extracted by 5 methods, including simple, enzyme-assited, and microwave-assisted hydrodistillation, extraction with solvent and supercritical carbon dioxide. The volatile compounds of the products were analyzed by GC-MS. Almost all samples contain some common characteristic components, such as Valerianol, Agarospirol, Eudesmol , Eudesmol <10-epi-g->, 2-Allyl-4-methylphenol, Guaiol and Neopetasone. However, there were obvious differences in yields, composition, and number of identified components. The application of the more advanced methods for the extraction of agarwood resulted in saving of time and energy, and some improvement of product yield. However, these methods also lead to unconventional products with many unknown components, what requires further investigations.
EFFECTIVE METHOD OF POLYPHENOL EXTRACTION FROM SESAME CAKE USING MICROBIAL FERMENTATION BY LACTOBACILLUS BREVIS NCTH24
Authors: Son Le Huy , Anh Nguyen La , Huong Dang Thu , Tram Ly Ngoc
Published: October 2018

Sesame seed is not only nutrient rich food but also of high polyphenol content. The total polyphenol content of Sesamum indicum’s bran can reach up to 150 mg/g. Among phenolic compounds, sesame lignans and anthocyanin were reported to have bioactive activities against diseases. The research focused on the development of method for sesame cake fermentation by Lactobacillus brevis NCTH24 to get high polyphenol content. It was found that fermentation medium of the following contents: 1/10 (w/v) ratio of sesame cake to distilled water, supplemented with 15g/l yeast extract and 1g/l glucose, adjusted to pH 6.0 then inoculated with 8% (v/v) inoculum of Lactobacillus brevis NCTH24 equivalent to 8.4*10^7 CFU/ml, to ferment at 30oC for 12h. As a result, the total polyphenol, flavonoid contents (calculated per gram dry sesame cake) and antioxidant activity through scavenged DPPH amount obtained from sesame cake fermented supernatant were 21.96 mg, 0.135 mg and 0.38 mg DPPH/30 min, respectively. They were significantly higher than those from sesame cake by extraction using methanol solvent (polyphenol 2.29 mg, flavonoid 0.05 mg and scavenged DPPH amount 0.19 mg/30 min).
STUDY ON CHEMICAL CONSTITUENTS AND BIOLOGICAL ACTIVITIES OF ALPINIA KWANGSIENSIS T. L. WU AND S. J. CHEN COLLECTED IN VIETNAM
Authors: Minh Tran Thi
Published: October 2018

Three compounds named ester methyl-trans-p-coumarate (1), 7-hydroxy-6-methoxycoumarin (2), and (+)-gallocatechin (3) have been isolated from the ethyl acetate fraction of methanol extract of Alpinia kwangsiensis roots collected in Thai Nguyen province. Their structures were elucidated on the basis of spectroscopic data and by comparison with their spectral data reported in literature. This is the first isolation of three compounds from this species. The ethyl acetate fraction was found to be active against bacterias as Staphylococcus aureus and Bacillus subtilis with the IC50 values ranging at 74.65 mg/ml and 80.54 mg/ml, respectively. This fraction also showed antioxidant activity through DPPH test with the EC50 value 87.98 mg/ml.
Triterpenoids from a Vietnamese medicinal plant Selaginella rolandi-principis Alston and their PTP1B Inhibitory activity
Authors: Phi Hung Nguyen
Published: October 2018

As part of an ongoing search for new protein tyrosine phosphatese 1B (PTP1B) inhibitors from medicinal plants, the methanol extract of Selaginella rolandi-principis Alston was found to possess PTP1B inhibition. Thus, bioassay-guided separation of this active extract led to the identification of four compounds (1‒4) as active principles. Their chemical structures were elucidated by extensive analysis of spectroscopic and physicochemical data. Among the isolates, compounds 1–3 exhibited potential inhibitory activities with IC50 values of 18.8 ± 0.7, 5.6 ± 0.9, and 28.4 ± 1.2 µM against PTP1B. In this assay, ursolic acid as positive control displayed an IC50 value of 3.46 ± 0.07 µM.
A Comparison of the Cytotoxic Activity of Extracts from Artificial Fruiting Bodies and Mycelial Biomass of Cordyceps neovolkiana (DL004) Fungus
Authors: Nguyễn Dũng Chí
Published: October 2018

ABSTRACTC-HCTN-69Cordyceps neovolkiana is an insect-parasitic fungus, naturally distributed in the Langbiang mountain, Tam Dao and Ba Vi national parks of Vietnam. This study assessed and compared the in vitro cytotoxic activity of crude extracts from fruit bodies and biomass of artifical C. neovolkiana fungus against human Jurkat (acute T cell leukemia) and breast carcinoma (MCF-7) cells using the sulforhodamine B (SRB) assay. We obtained the extracts via the ethanol extraction and liquid-liquid extraction with four different solvents; ethanol (EtOH) petroleum ether (60 – 80oC) (PE), etyl acetate (ET), butanol (BU) and water (W), successively. The result shows both the cytotoxic potential of biomass and fruit-body extracts were determined the IC50 value at 0 – 100 µg/mL concentration. The PE-fruit-body extract displayed the highest cytotoxic activity on MCF-7 and Jurkat cell lines with IC50 values of 76,30 ± 1,20 µg/mL and 37,18 ± 1,39 µg/mL, respectively. Beside that, the PE- biomass extracts respectively showed the highest cytotoxic activity on MCF-7 and Jurkat cell lines with IC50 values of 26,94 ± 1,62 µg/mL and 15,50 ± 0,19. Obviously, we need to study further about the cytotoxic mechanism PE-fruit-body and biomass extracts on MCF-7 and Jurkat cells and chemical composition analysis of extracts to possibly use as a promising anticancer agent.
EFFECT OF RICE BRAN OIL ON MYCELIAL BIOMASS PRODUCTION, BIOSYNTHESIS AND BIOACTIVITIES OF POLYSACCHARIDES BY OPHIOCORDYCEPS SINENSIS FUNGUS
Authors: Hoang Nguyen Tai
Published: October 2018

Ophiocordyceps sinensis (syn. Cordyceps sinensis), which is an entomopathogenic fungus, is widely known as “Dong Chong Xia Cao” in Traditional Chinese Medicine. It continues to attract scientists’ attention due to the diversity of bioactive compounds such as polysaccharides, cordycepin, adenosine, amino acids, peptides, and ergosterol. Among them, exopolysaccharides (EPS) from the culture broth has possessed many precious bioactivities, for example, immunomodulatory, antitumor, antioxidant activity, and etc. Interestingly, previous studies have demonstrated that plant oils have positive affects to the growth and biosynthesis of secondary metabolites of medicinal fungi. Therefore, the aim of this study is to enhance the biomass growth and EPS biosynthesis of O. sinensis fungus by implementing rice bran oil (RBO) at various concentrations from 1% to 8% (v/v) into the culture medium. The results illustrated that, in the RBO-added media, the biomass of mycelial and EPS production increased significantly compared to non-RBO medium. In particular, biomass yield was 26.6 g/L in medium within 6% RBO, and EPS production was 4.62 g/L in medium within 5% RBO. Importantly, inhibition of xanthine oxidase activity of the IPS and EPS crudes from the (2, 8% respectively). RBO-supplemented broths rose considerably compared to the control EPS. Besides, at 5% of RBO, the anti-inflammatory activity of EPS was highest with IC50 = 824.947 (µg/ml). In addition, the minimum IC50 value of IPS was 1529.061 (μg/ml) when added to the culture medium 4% RBO. In conclusion, these data have exposed evidence that the RBO was potential to dramatically exhibit the biomass production and EPS biosynthesis of O. sinensis fungus and improve their bioactivities.
CHARACTERIZATION OF CYTOCHALASINS AND STEROIDS FROM THE FRUITING BODIES OF Daldinia concentrica (BOLTON FR. CES. & DE NOT) IN VIETNAM
Authors: Tran Thang Dinh
Published: October 2018

ABSTRACT-HCTN_14[11]-cytochalasa-6(12), 13-diene- 1, 21-dione-7, 18, 19- trihydroxy-16,18-dimethyl-10-phenyl-(7S*, 13E, 16S*, 18S*, 19R*) (1), [11]-cytochalasa-6(12),13-dien-1,21-dion-7,18-dihydroxy-16,18-dimethyl-10-phenyl -(7S*, 13E, 16S*, 18R*) (2), ergosterol (3) and ergosterol peroxit (4) were isolated from the methanolic extract of the fruit body of Daldinia concentrica. The structures of these compounds were elucidated using a combination of UV, IR, 1D and 2D NMR techniques (1H-, 13C-NMR, COSY, HSQC and HMBC) and MS analyses.
ENTRAINER SELECTION FOR SEPARATION OF AZEOTROPIC MIXTURES BY DISTILLATION METHODS
Authors: Tien Thi Luot
Published: October 2018

Azeotropic or close – boiling mixtures often preclude conventional distillation as a method of separation. Instead, extractive or azeotropic distillations are commonly used to separate azeotropic or close – boiling mixtures. For the design of those separation units, selecting suitable entrainers (solvents) is a key step. The traditional method for solving this problem is to use experimentation which is time – consuming and expensive. Currently available selection criteria are inadequate. They contradict one another and often lead to incorrect conclusions. Indeed, for a minimum boiling azeotrope, the existing entrainer selection rules state that one should use a high boiling component that introduces no additional azeotrope (Benedict & Rubin, 1945), an intermediate boiling component that introduces no additional azeotrope (Hoffman, 1964), a component which introduces no distillation boundary between the azeotropic constituents (Doherty & Caldarola, 1985), and either a low boiling component that introduces no additional azeotrope or a component that introduces new minimum boiling azeotrope (Stichlmaric, Fair & Bravo, 1989).In this work, Aspen Plus simulator was used to propose an entrainer selection procedure based on the criteria: 1) A good entrainer is a component that eliminates the azeotrope easily (i.e. even when it’s concentration is small). 2) A component that yields high relative volatilities αAB between the two azeotrope constituents.
TRITERPENES FROM DOCYNIA INDICA FRUITS AND THEIR CYTOTOXIC ACTIVITY
Authors: Duy Lê Xuân
Published: October 2018

Five triterpenes were isolated from the ethyl acetate fraction of methanolic extract of Docynia indica fruits. Their structures were determined to be pomolic acid (1), maslinic acid (2), ursolic acid (3), 23-hydroxy ursolic acid (4) and euscaphic acid (5) by comparison of physicochemical, NMR and mass spectral data with those reported in the literature. All triterpenes (1 – 5) were isolated for the first time from Docynia indica. Compounds 1 – 5 were evaluated for their cytotoxic activity using MTT assay, of which 23-hydroxy ursolic acid (3) and ursolic acid (4) showed cytotoxic activities against HeLa and Hep-G2 cancer cell lines.
ANTIBACTERIAL ACTIVITIES OF THE ESSENTIAL OIL OF VIETNAMESE HOLY BASIL (Ocimum sanctum L.) AGAINST FOOD-BORNE BACTERIA AND FUNGI SPECIES
Authors: CUNG THI TO QUYNH
Published: October 2018

Antimicrobial activities of essential oil (EO) of Vietnamese holy basil (Ocimum sanctum L.) were screened against several food-borne bacteria and fungi species. The main volatile components detected in the holy basil EO were eugenol (53.61%), (E)-caryophyllene (25.37%), (β)-elemene (15.86%), germacrene A (2.03%). A significant growth inhibition of this EO with some different concentrations against Escherichia coli ATCC® 25922™ (E. coli), Staphylococcus aureus ATCC ® 25923 ™ (S. aureus), Bacillus subtilis ATCC® 11774™ (B.subtilis), Bacillus cereus ATCC® 13061™ (B.cereus) and Candida albicans ATCC 10231, Rhizoctonia solani, Fusarium oxysporum were observed by the standard disc diffusion method. The inhibition zone for each isolate by holy basil EO obtained from 5 µl and 10 µl of EO ranged from 15.3 - 16.4 mm and 16.7 – 18.4 mm in diameter, respectively. The minimum inhibitory concentration (MIC) of holy basil EO was 0.78 µl/ml determined by a micro-dilution method in MHB liquid medium. The bactericidal concentrations (MBC) was 1.56 µl/ml in all isolates tested. The antifungal properties of the holy basil EO were also determined in this study against three important pathogenic fungi such as Candida albicans, Rhizoctonia solani and Fusarium oxysporum with the inhibition zone ranges from 20 to 30 mm. The results suggested that holy basil EO can be applied in food industries as natural flavoring preservatives/additives to control food spoilage and food-borne pathogenic bacteria and fungi causing severe destruction in food.
STRUCTURAL ELUCIDATION OF FIVE PHENOLIC COMPOUNDS FROM THE RHIZOMES OF CURCULIGO ANNAMITICA GAGNEP
Authors: Liên Tạ Thị
Published: October 2018

Phytochemical research on the chloroform and ethyl acetate extracts of the rhizome of Curculigo annamitica Gagnep (Hypoxidaceae) collected in Binh Chau-Phuoc Buu Nature Reserve, Ba Ria - Vung Tau province, led to the isolation and structural elucidation of five phenolic compounds namely 2-hydroxy-3,4-dimethoxybenzoic acid (1), 2-hydroxy-6-methoxybenzoic acid (2), 4-hydroxybenzoic acid (3), p-coumaric acid (4) and 2-(ethoxymethyl)benzene-1,4-diol (5). Their chemical structures were confirmed by spectroscopic methods including HR-ESI-MS, 1D and 2D-NMR and compared with reported data. Compound 1 was known to be present for the first time from the family Hypoxidaceae.Keywords: Curculigo annamitica Gagnep (Hypoxidaceae), rhizome, phenolic compounds, 2-hydroxy-3,4-dimethoxybenzoic acid