RESUMEN Colombia posee gran diversidad de plantas medicinales, pero pocas han sido objeto de investigación. En este trabajo se evaluó la actividad antiproliferativa de aceites esenciales obtenidos por hidrodestilación asistida por microondas. Se analizaron 15 muestras de 11 especies en ensayos del MTT en células cancerosas MCF-7, HeLa y HepG-2 y se incluyeron células normales humanas (HEK293) y de animales (Vero y B16F10) para evaluar selectividad. La composición química de muestras activas se determinó por cromatografía de gases acoplada a espectrometría de masas (GC-MS). Aceites esenciales de cuatro especies mostraron actividad antiproliferativa (CI50: 50 μg/mL) en células HeLa y/o MCF-7, en el siguiente rango (índice de selectividad en paréntesis): Pipercumanense H.B.K. (4,7) > Piper subflavum var. espejuelanum C.DC (3,9) > Salvia officinalis L. (3,6) > Piper eriopodom (Miq.) C. DC. (3,1). Ninguna muestra fue activa en células HepG-2. El análisis por CG-MS identificó β-cariofileno, a-copaeno, β-pineno, α-pineno y linalol como componentes mayoritarios. Los aceites esenciales activos pueden ser puntos de partida para desarrollo de medicamentos herbales para cuidado paliativo del cáncer.

ABSTRACT Colombia has a great diversity of medicinal plants, but few have been investigated. In this work, the antiproliferative activity of essential oils obtained by microwave-assisted hydrodistillation was evaluated. Fifteen samples from 11 species were analyzed in MTT assays in cancer cells MCF-7, HeLa and HepG-2, and normal human cells (HEK293) and animal cells (Vero and B16F10) were included to evaluate selectivity. The chemical composition of the active oils was determined by gas chromatography coupled to mass spectrometry (GC-MS). Essential oils from four species showed antiproliferative activity (IC50: <50 μg / mL) in HeLa and / or MCF-7 cells, in the following range (selectivity index in parenthesis): Piper cumanense H.B.K. (4.7) > Piper subflavum var. espejuelanum C. DC (3.9) > Salvia officinalis Linneo. (3.6) > Piper eriopodom (Miq.) C.DC. (31). The CG-MS analysis identified β-caryophyllene, a-copaene, β-pinene, a-pinene and linalool as major components. Active essential oils could serve as starting points to develop herbal medicines for cancer palliative care.

Abstract INTRODUCTION: In the present study, we determined the chemical composition of Clinopodium macrostemum essential oil obtained by microwave-assisted hydrodistillation and its effect on the growth and development of Culex quinquefasciatus mosquito larvae. METHODS: The essential oil compounds were identified by gas chromatography-mass spectrometry analysis, and bioassays were conducted to evaluate the influence on the developmental stages of early second instar larvae of Cx. quinquefasciatus until the emergence of adults, using essential oil concentrations of 50, 100, 200, 400, and 800mg/L. RESULTS: The gas chromatography-mass spectrometry analyses revealed that the leaf essential oil of C. macrostemum contained 32 compounds and the major chemical compounds identified were linalool (55.4%), nerol (6.4%), caryophyllene (6.25%), menthone (5.8%), geraniol acetate (4.1%), terpineol (3.7%), and pulegone (2.8%). The essential oil yield obtained by microwave-assisted hydrodistillation was 0.8% at 20 min. The treatments showed lethal concentrations (LC50 and LC90) of 22.49 and 833.35mg/L, respectively, after the final measurement of the total number of dead larvae (second, third, and fourth instars), and LC50 and LC90 of 6.62 and 693.35mg/L, respectively, at the end of the experimental period. The essential oil inhibited the growth and development of the mosquito larvae by 32% (relative growth index = 0.68) at 50mg/L, and up to 47% (relative growth index = 0.53) at 800mg/L. CONCLUSION: The present study demonstrated the larvicidal effect of C. macrostemum essential oil on Cx. quinquefasciatus, which can be attributed to the oxygenate compounds obtained by the extraction method.

Abstract The search for new insecticides to control dengue fever, chikungunya, and Zika vectors has gained relevance in the past decades. The aim of the present study was to evaluate the larvicidal action of essential oils (EOs) from Thymus vulgaris, Salvia officinalis, Lippia origanoides, Eucalyptus globulus, Cymbopogon nardus, Cymbopogon martinii, Lippia alba, Pelargonium graveolens, Turnera diffusa, and Swinglea glutinosa on Aedes (Stegomyia) aegypti. The EOs were extracted by microwave-assisted hydrodistillation and characterized by gas chromatography/mass spectrometry (GC/MS). The chemical components of the EOs were identified by linear retention indices and mass spectra. Lethal concentrations (LC50 and LC95) were determined by probit analysis using larvae of Ae. aegypti between the third and the fourth instars. All EOs achieved larvicidal activity at LC50 values lower than 115 mg/L. The lowest LC50 value (45.73 mg/L) corresponded to T. vulgaris EO, whereas C. martinii EO showed the highest LC50 (LC50 = 114.65 mg/L). Some EO mixtures showed lower LC50 than oils used individually, such as the mixtures of L. origanoides + S. glutinosa (LC50 = 38.40 mg/L), T. diffusa + S. glutinosa (LC50 = 63.71 mg/L), and L. alba + S. glutinosa (LC50 = 48.87 mg/L). The main compounds of the EOs with highest larvicidal activity were thymol (42%) and p-cymene (26.4%).

ABSTRACT In this study essential oil of the aerial parts of Heracleum persicum a spice widely used in Iran was isolated by conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD) techniques. The extraction yield was determined and the chemical compositions of essential oils were identified by the application of gas chromatography/mass spectrometry (GC/MS). The antioxidant activity was determined by two different methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and oven test methods. Although the main compounds of essential oils by the both extraction methods were similar, the essential oil extracted by HD with lower extraction efficiency showed more diverse compounds. The evaluation of antioxidant activity of the essential oil measured by delay in sunflower oil oxidation indicated that the antioxidant activity was dependent on the concentration which increased when higher concentrations of the essential oils were applied. The results of DPPH radical assay also indicated that the percentage of inhibition increased with increasing of essential oil concentration and IC50 value for essential oil extracted by MAHD method was obtained 1.25 mg/mL. Therefore the Heracleum persicum essential oil might be recommended for use as a flavoring agent and a source of natural antioxidants in functional foods, formulation of the supplements and in medicinal due to numerous pharmacological activities.

Abstract Tomato and papaya are crops of great economic importance to producers from Chiapas; however, they are experiencing a production crisis due to limited options for alternative management of its major diseases. In this study, were assessed in vitro the regulatory effect hidrodestillates and Cinnamomum zeylanicum, Syzygium aromaticum and Pimienta dioica oils (obtained by traditional distillation and microwave assisted) on Alternaria solani, Fusarium oxysporum isolated from Lycopersicon esculentum and on Colletotrichum gloeosporioides isolated from Carica papaya. Poisoned medium technique was used in a first trial a concentration of hidrodistillate at 30% (v/v) and 1% for oils were used. Then the minimum inhibitory concentration was determined. The regulatory effect was determined by quantifying mycelial growth and conidia formation. The results indicated that clove hidrodistllate completely inhibited A. solani and F. oxysporum at 30% and 10% to C. gloeosporioides, while cinnamon microwaveassisted inhibited A. solani and C. gloeosporioides 10% and 30% to F. oxysporum, and clove at 30% inhibits F. oxysporum and A. solani and at 10% C. gloeosporioides and cinnamon and clove oils at 0.05% inhibited A. solani and C. gloesporioides. It is concluded that hidrodestillates and oils from C. zeylanicum, Z. aromaticum and P. dioica obtained by microwave are more efficient in inhibiting the growth of these pathogens than by traditional distillation, which can be an alternative for its management.

Resumen El tomate y la papaya son cultivos de gran importancia económica para productores de Chiapas; sin embargo, atraviesan por una crisis productiva debida a las escasas alternativas para el manejo alternativo para sus principales enfermedades. En este estudio, se evaluó in vitro el efecto regulador de hidrodestilados y aceites de Cinnamomum zeylanicum, Syzygium aromaticum y Pimienta dioica (obtenidos por destilación tradicional y asistido por microondas) sobre Alternaria solani, Fusarium oxysporum aislados de Lycopersicum esculentum y sobre Colletotrichum gloesporioides aislado de Carica papaya. Se utilizó la técnica de medio envenenado, en un primer ensayo se probó concentración 30% (v/v) de hidrodestilados y 1% para aceites. Luego se determinó la concentración mínima inhibitoria. El efecto regulador se determinó cuantificando crecimiento micelial y formación de conidias. Los resultados indicaron que el hidrolato de clavo obtenido por destilación inhibió totalmente a A. solani y F. oxysporum al 30% y 10% a C. gloesporioides, mientras que los asistidos por microondas de canela inhibieron a A. solani y C. gloesporioides 10% y 30% a F. oxysporum, y el de clavo a 30% inhibe a F. oxysporum y A. solani y al 10% C. gloesporioides y los aceites de canela y clavo al 0.05% inhibieron a A. solani y C. gloesporioides. Se concluye que los hidrodestilados y aceites de C. zeylanicum, Z. aromaticum y P. dioica obtenidos por microondas son más eficientes en inhibir el desarrollo de éstos patógenos que por destilación tradicional, los cuales pueden ser una alternativa para su manejo.

En este estudio se evaluó el efecto del origen (cuatro zonas), la época de recolección (lluviosa y seca) y la edad de las hojas (jóvenes y maduras) sobre el rendimiento y el contenido de timol del aceite esencial (AE) de plantas de Lippia origanoides, que crecen en estado silvestre en la región del Alto Patía al suroccidente de Colombia. Las extracciones de AE se realizaron mediante la técnica de hidro-destilación asistida por radiación de microondas (MWHD) y fueron analizadas por cromatografía de gases. Los rendimientos de AE variaron entre 2.53 y 3.28% y sólo se encontraron diferencias significativas (P < 0.05) para la zona de origen de las plantas. Para el contenido de timol se observaron diferencias relacionadas con la época de recolección, siendo mayor el contenido en las muestras recolectadas en época seca. Los compuestos principales identificados en los AE fueron timol (50.8 - 81.6%), r-cimeno (7.5 - 19.5%) y g-terpineno (2.3 - 7.4%).

The purpose of this research was to evaluate the effect of the origin (4 localities), the plant's leaves age (young and mature) and the season (rainy and dry season) on the essential oil's (EOs) yield and thymol content of Lippia origanoides growing wild in the Alto Patía region (south-west of Colombia). The extractions were performed through microwave-assisted hydrodistillation technique (MWHD) and the EOs were analyzed by gas chromatography. Yields of EOs varied between 2.5 and 3.3% and were obtained where the origin factor showed statistical differences (P< 0.05) over the yielding. Taking into account the thymol content, differences related to the season were observed. The highest thymol content in the EOs were obtained in the dry season. The major compounds identified in the EOs were thymol (50.8 - 81.6%), r-cymene (7.5 - 19.5%) and g-terpinene (2.3 - 7.4%).

Introduction: Acmella ciliata (Kunth) Cass. is a native weed of northern South America known by its aliphatic alkamide content and used as an anesthetic and analgesic for toothache and sore throat. Objective: to obtain, to analyze and to evaluate the biological activities of essential oils from Acmella ciliata (Kunth) Cass flowers and leaves. Methods: Acmella ciliata essential oils were obtained by hydrodistillation and microwave-assisted hydrodistillation and analyzed by gas chromatography coupled to mass spectrometry. The biological activity of both essential oils was determined by using the modified agar-well diffusion assay, evaluating their activities against five bacteria and one fungus, along with tests of toxicity in Artemia salina (Lethal Dose 50). Results: microwave-assisted hydrodistillation was the technique with the best performances in the extraction of Acmella ciliata. essential oils. Their volatile fractions contain a high proportion of sesquiterpenes such as β-trans-caryophyllene, the major component. Essential oils at two different concentrations (25 mg/mL and 15 mg/mL) showed a strong antimicrobial activity against gram-positive bacteria Staphylococcus aureus and Staphylococcus epidermidis, in addition they exhibited low toxicity against Artemia salina, presenting mean lethal doses of 176, 156 and 100,104 ppm for the essential oils from leaves and flowers, respectively. Conclusions: Acmella ciliata essential oils are products with high content of terpenoids and marked antimicrobial activity against gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis) and low toxicity against Artemia salina.

Introducción: Acmella ciliata (Kunth) Cass. es una arvense nativa del norte de Suramérica conocida por su contenido de alcamidas alifáticas, se usa popularmente como anestésico y analgésico contra los dolores de muelas y de garganta. Objetivos: obtener, analizar y evaluar la actividad biológica de los aceites esenciales de las flores y hojas de Acmella ciliata (Kunth) Cass. Métodos: se obtuvieron los aceites esenciales de Acmella ciliata por hidrodestilación e hidrodestilación asistida por microondas, y se analizaron por cromatografía de gases acoplados a un espectrómetro de masas. La actividad biológica de los aceites esenciales se determinó mediante el método modificado de pozos de agar, se evaluaron sus actividades antimicrobianas frente a 5 bacterias y 1 hongo, junto con pruebas de toxicidad en Artemia salina. Resultados: la hidrodestilación asistida por microondas fue la técnica con mejores rendimientos en la extracción de los aceites esenciales de Acmella ciliata. Sus fracciones volátiles contienen una alta proporción de sesquiterpenos como el trans-β-cariofileno, su componente mayoritario. Los aceites esenciales a 2 concentraciones diferentes (25 y 15 mg/mL) presentaron una marcada actividad antimicrobiana frente a las bacterias grampositivas Staphylococcus aureus y Staphylococcus epidermidis; además exhibieron una baja toxicidad contra Artemia salina, con dosificaciones letales medianas de 176,156 ppm y 100,104 ppm para el aceite esencial de las hojas y flores, respectivamente. Conclusiones: los aceites esenciales de Acmella ciliata son productos que presentan un alto contenido de terpenoides, con marcada acción antimicrobiana frente bacterias grampositivas (Staphylococcus aureus y Staphylococcus epidermidis) y baja toxicidad en Artemia salina.

Antibacterial properties and chemical characterization of the essential oils from summer savory (Satureja hortensis) extracted by microwave-assisted hydrodistillation (MAHD) were compared with those of the essential oils extracted using the traditional hydrodistillation (HD) method. While MAHD at 660 W required half as much time as HD needed, similar antibacterial efficacies were found from the essential oils obtained by the two extraction methods on two food pathogens (Staphylococcus aureus, a gram positive bacterium, and Escherchia coli, a gram negative bacterium). Also, as it was the case with the essential oils extracted by HD, that of MAHD indicated greater influence on S. aureus than on E. coli. The compositions of the extracted essential oils were also studied using GC-MS analysis. The same components with negligible differences in their quantities were found in the extracted essential oils using the two methods outlined above. Overall, to reduce the extraction time, MAHD can be applied at higher microwave levels without any compromise in the antibacterial properties of the essential oils extracted.

Introducción: Lippia alba (Mill) N.E. Brown es una planta aromática perteneciente a la familia Verbenaceae, ampliamente usada en Suramérica y Norteamérica como infusión contra la hipertensión, problemas digestivos, náuseas y resfriados. Objetivo: En el presente estudio, se evaluó la actividad antiviral in vitro frente al Herpesvirus Humano Tipo 1 (HSV-1), de veinte aceites esenciales de L. alba y, diez de sus componentes mayoritarios. Metodología: La actividad antiviral in vitro fue evaluada empleando la técnica modificada, de titulación del punto final (EPTT). Los aceites esenciales, de plantas de L. alba recolectadas de diferentes regiones del país, fueron obtenidos por hidrodestilación asistida con radiación de microondas (MWHD). Se determinó por cromatografía de gases-espectrometría de masas (GC-MS), la composición química, de los veinte aceites esenciales de L. alba, identificándose dos quimiotipos: citral y carvona. Resultados y conclusiones: Los aceites quimiotipo carvona, BC1 y CA2, mostraron actividad antiherpética in vitro, moderada sobre monocapa de células HeLa infectadas, con valores de Rf de 1x10(1,5), en concentraciones, de 250 μg/mL y 125 μg/mL, respectivamente. Los controles positivos, sulfato de heparina y aciclovir, redujeron el titulo viral con valores de Rf, en orden, de 1x10² y 1x10(4). Ninguno de los monoterpenos evaluados mostró actividad contra el HSV-1. Salud UIS 2010; 42: 230-239

Introduction: Lippia alba (Mill.) N.E. Brown is an aromatic shrub belonging to the Verbenaceae family, which is widely used all over South and Central America as an infusion against, hypertension, digestive troubles, nausea and cold. The antiviral activity in vitro against Herpesvirus 1, Human (HSV-1) of twenty essential oils of L. alba and ten of its components were evaluated. Methodology: The antiviral activity was determined using a modified end-point titration technique (EPPT). The essential oils from L. alba collected in different regions of Colombia were obtained by microwave-assisted hydrodistillation (MWHD). Their chemical compositions were determined by GC and GC/MS. Two chemotypes were distinguished, characterized by carvone and citral as main constituents. Results and conclusions: Carvone chemotype oils BC1 and CA2 were found to be moderate antiviral activity over infected confluent monolayers of HeLa cells with Rf value of 1x10(1,5) at a concentration of 250 μg/mL and 125 μg/mL, respectively. Heparin sodium salt and acyclovir were used as positive controls and showed Rf values of 1x10² and 1x10(4), respectively. None of monoterpenes tested showed antiviral activity against HSV-1. Salud UIS 2010; 42: 230-239

Treze óleos essenciais de plantas da Colômbia, obtido por hidrodestilação ou hidrodestilação assistida por microondas, da planta inteira, caule, folhas e flores, foram analisados por técnicas de espectrometria de massa acoplada a cromatografia gasosa. Foi avaliada a citotoxicidade de óleos essenciais utilizando o ensaio com Artemia salina e suas atividades antioxidantes medindo seus efeitos sobre os níveis de substâncias reativas ao ácido tiobarbitúrico em microssomas de fígado de rato induzida por Fe2+/H2O2. Cinco óleos apresentaram alta citotoxicidade (LC50<10 µg/mL) sobre o ensaio de Artemia salina. A atividade antioxidante do óleo essencial de Ocotea sp., Tagetes lucida e Lippia alba (quimiotipo geranial) apresentaram os menores valores de Concentração Eficaz (CE50), na ordem de 31,1, 37,9 e 94,9 µg/mL, respectivamente. Os principais componentes desses óleos foram α-pineno (42%), estragol (95,7%) e geranial (30,4%), respectivamente. Elettaria cardamomum e Lippia alba (quimiotipo carvona, Tolima) apresentaram moderada atividade antioxidante com valores de CE50 de 130,5 e 174,4 µg/mL, respectivamente. Os óleos essenciais de mollis Minthostachys mollis, Lippia alba (quimiotipo carvona, Cundinamarca), e Piper sanctifelisis não mostraram atividade antioxidante (CE50>1000 µg/mL).

Thirteen essential oils from Colombian plants, obtained by hydrodistillation or microwave-assisted hydrodistillation of total plant, stem, leaves, and flowers were analyzed by gas-chromatography-mass spectrometry techniques. Cytotoxicity of essential oils was assessed using the brine shrimp assay, and their antioxidant activities measuring their effects on the levels of thiobarbituric acid reactive substances on rat liver microsomes induced by Fe2+/H2O2. Five oils showed high cytotoxicity (LC50<10 µg/mL) on the brine shrimp assay. The antioxidant activity of the essential oil from Ocotea sp., Tagetes lucida and Lippia alba (geranial chemotype) showed the lowest mean effective concentrations (EC50), with values of 31.1, 37.9 and 94.9 µg/mL, respectively. The main components for these oils were α-pinene (42%), estragole (95.7%) and geranial (30.4%), respectively. Elettaria cardamomum and Lippia alba (carvone chemotype, Tolima) presented moderate antioxidant activities with EC50 values of 130.5 and 174.4 µg/mL, respectively. Essential oils from Minthostachys mollis, Lippia alba (carvone chemotype, Cundinamarca), and Piper sanctifelisis did not show antioxidant activity (CE50>1000 µg/mL).

Los aceites esenciales y pectinas se obtienen de los subproductos de la extracción de los jugos de mandarina, naranja, toronja y pomelo. Para la extracción de los aceites esenciales se emplea la técnica de hidrodestilación asistida por radiación de microondas. La identificación de sus componentes se lleva a cabo mediante cromatografía de gases acoplada a espectrometría de masas, calculándose sus cantidades relativas. Las pectinas se extraen mediante hidrólisis ácida. Los mayores rendimientos de aceite esencial (0.23%) y pectina (25.2% en base seca) se obtienen del pomelo.

Essential oils and pectins are obtained from the mandarin, orange, grapefruit and pommelo by-products. The essential oils are isolated by microwave-assisted hydrodistillation. The compounds identification is carried out by gas chromatography coupled to mass spectrometry and their relative amounts are calculated. The pectins are extracted by acid hydrolysis. The highest essential oil (0.23%) and pectins (25.2% dry basis) yields are obtained from pommelo.