Antibacterial Activity and Reversal of Multidrug Resistance of Tumor Cells by Essential Oils from Fresh Leaves, Flowers, and Stems of Montanoa quadrangularis Schultz Bipontinus (Asteraceae) Collected in Mérida-Venezuela.

Essential oils obtained by hydrodistillation of Montanoa quadrangularis leaves, flowers, and stems were analyzed by GC and GC/MS techniques revealing myrcene, limonene, ß-phellandrene, and sabinene among the main components. The aim of the present study was to evaluate the MDR modulator activity on human MDR1 gene transfected mouse lymphoma cell line and the antimicrobial activity on the essential oils obtained from different parts of the species under investigation. The results revealed that MQL caused a similar increase in the fluorescence activity of the cells at 0.02 µL/mL comparing to the Verapamil® value. The antimicrobial assay was carried out according to the disc diffusion method. Five different bacterial strains (Staphylococcus epidermidis, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli AG 100, and Escherichia coli AG100A) were treated with the essential oils and the zones of inhibition were determined on TSA plates and TSA agar plates supplemented with Tween 20. MQF and MQL showed activity against B. subtilis, S. epidermidis, and E. coli AG 100A while MQS was only active against E. coli AG 100A on TSA agar plates experiment. In case of TSA agar plates supplemented with 0.1 v/v% Tween 20 detergent, MQF showed inhibition on B. subtilis, S. epidermidis, and E. coli AG 100A; MQL was active against B. subtilis, E. coli AG 100, and E. coli AG 100A while MQS was only active against E. coli AG 100A.

Antimicrobial activity of four Valeriana (Caprifoliaceae) species endemic to the Venezuelan Andes / Actividad antimicrobiana de cuatro especies de Valeriana (Caprifoliaceae) endémicas de los Andes venezolanos

Abstract Valeriana L. genus is represented in Venezuela by 16 species, 9 of these are endemic of Venezuelan Andes growing in high mountains at 2 800 masl. In this investigation, four species were analyzed in order to determine the main secondary metabolites and antimicrobial activity of extracts obtained from aerial parts of Valeriana parviflora, V. rosaliana, V. triplinervis and V. phylicoides. Alkaloids, flavonoids, tannins, sterols, triterpenoids and saponins were qualitatively observed in all methanolic extracts tested. The color intensity or a precipitate formation was used as analytical response to these tests. Antimicrobial activity was evaluated against Gram positive, Gram negative bacterial strains and yeast, using disc diffusion method. N-hexane extracts of V. triplinervis and V. rosaliana showed the highest efficiency against Staphylococcus aureus, exhibiting inhibition zones of 16 mm and 15 mm; MIC (Minimal Inhibition Concentration) values were observed at 116 mg/mL and 150 mg/mL, respectively. Dichloromethane and methanolic extracts of V. triplinervis and methanolic extract of V. rosalianashowed a rather moderate activity (MIC between 200 to 316 mg/ml) but a very weak antibacterial activity was observed in V. phylicoides and V. parviflora extracts (MIC > 420 mg/mL). None of the extracts assayed in this investigation showed any activity against Candida albicansand Candida krusei. Statistical analysis showed no significant differences on the different polarity extracts assayed with respect to antimicrobial activity against S. aureus (P > 0.10), however it was observed significant differences between the Valeriana species analyzed (P < 0.10) in relation to the minimal inhibitory concentration (MIC). Rev. Biol. Trop. 66(3): 1282-1289. Epub 2018 September 01.

Resumen El género Valeriana, está representado en Venezuela por 16 especies, 9 de las cuales son endémicas de Los Andes y crecen en las altas montañas a 2 800 msnm. En esta investigación cuatro especies fueron analizadas para determinar los principales metabolitos secundarios y la actividad antimicrobiana de los extractos obtenidos de las partes aéreas de Valeriana parviflora, V. rosaliana, V. triplinervis y V. phylicoides. Compuestos como alcaloides, flavonoides, taninos, estroles, triterpenos y saponinas fueron detectados cualitativamente en todos los extractos metanólicos ensayados. La intensidad del color o la formación de un precipitado se tomaron como respuesta positiva para estos análisis. Actividad antimicrobiana fue evaluada frente a bacterias Gram positivas, Gram negativas y levaduras, usando el método de difusión en discos. Los extractos en n-hexano de V. triplinervis y V. rosaliana mostraron la mayor eficiencia frente a Staphylococcus aureus, mostrando zonas de inhibición de 16 mm y 15 mm con valores de CIM (Concentración Inhibitoria Mínima) observados a 116 mg/mL y 150 mg/mL, respectivamente. Los extractos con diclorometano y metanol de V. triplinervis y metanol de V. rosaliana revelaron moderada actividad (CIM entre 200 y 316 mg/ml), mientras actividad muy leve se observó en los extractos de V. phylicoides y V. parviflora (CIM > 420 mg/mL). Ninguno de los extractos ensayados mostraron actividad frente a Candida albicans y Candida krusei. Los análisis estadísticos mostraron que no hay diferencia significativa entre los solventes de diferentes polaridades con relación a la actividad antimicrobiana frente a S. aureus (P > 0.10), sin embargo, sí se observó diferencia significativa (P < 0.10), entre las especies de Valeriana ensayadas con respecto a la concentración inhibitoria mínima (CIM).

Comparison of the chemical composition of Valeriana parviflora essential oils collected in the Venezuelan Andes in two different seasons.

The essential oils obtained by hydrodistillation of the aerial parts of Valerianaparviflora (Trevir) BM Vadillo, an endemic species of the Venezuelan Andes, collected from the same location in two different seasons (dry and rainy) of the year, were analyzed by GC/MS. The essential oil obtained during the dry season showed linalool (11.9%), eugenol (8.9%), p-menth-l-en-9-al (8.7%) and α-terpineol (7.7%) as main components, while the oil obtained from the rainy season collection showed o-xylol (16.2%), 3-methyl isovaleric acid (10.6%) and geranial (9.5%) as major compounds. Some of the differences in the composition of these oils might be due to the climatic conditions at the time of harvesting.

Essential oil composition and antimicrobial activity of Vismia macrophylla leaves and fruits collected in Táchira-Venezuela.

Hydrodistillation of Vismia macrophylla Kunth (Hypericaceae) leaves (L) and fruits (F) yielded 1.3%, v/w, and 5.6%, v/w, of essential oil, respectively. GC and GC-MS analyses showed the presence of twenty-four (96.4%, L) and thirty-one (96.6%, F) components, respectively. Major compounds identified in the leaf oil were γ-bisabolene (44.4%) and ß-bisabolol (14.9%), while those in the fruit oil were germacrene-D (12.1%), 6-cadinene (10.7%) and γ-bisabolene (22.3 %). Oil obtained from the fruits of V. macrophylla showed antibacterial activity against Gram-positive (S. aureus ATCC 25923 and E. faecalis ATCC 29212) as well as Gram-negative bacteria (E. coli ATCC 25922), with MIC values ranging from 150 µL/mL to 740 µL/mL. Oil obtained from leaves were active only on the Gram-positive bacteria S. aureus (100 µL/mL) and E. faecalis (500 µL/mL), but also showed antiyeast activity against Candida albicans CDC-B385 and C. krusei ATCC 6258 (600 µL/mL, each).

Jatropha curcas leaves analysis, reveals it as mineral source for low sodium diets.

Jatropha curcas is a perennial herb, belonging to the family Euphorbiaceae, found in countries such as India, Mexico and Venezuela. In the present study, proximate composition and mineral content on the leaves of J. curcas was analysed and compared to spinach (Spinacia oleracea L.) using a ICP-AES. The bromatologic test (dry material) results for ashes, proteins, lipids and carbohydrates revealed 23.4%, 28.0%, 3.2% and 45.4% for J. curcas; whereas for S. oleracea values were 28.9%, 20.8%, 0.5% and 49.9%. Furthermore, minerals found in both species ashes were: calcium, potassium, magnesium, iron and phosphorus, resulting that leaves of J. curcas are composed by three times the iron and calcium amount comparing to spinach; while sodium was absent from the former species. In this study Cu and Zn were found only in spinach, while Pb and As were not detected in any of the studied species. These results indicate that J. curcas leaves might be considered as mineral source suitable for animal and human consumption, especially for people who requires a low sodium diet.

Chemical composition and biological activity of Conyza bonariensis essential oil collected in Mérida, Venezuela.

The essential oil from aerial parts of Conyza bonariensis (L) Cronquist collected in Mérida was obtained by hydrodistillation and analysed by GC/MS. The major components were trans-beta-farnesene (37.8%), trans-ocimene (20.7%) and beta-sesquiphellandrene (9.8%). Cytotoxicity assay was also performed with the essential oil against HeLa (cervix carcinoma), A-459 (lung carcinoma) and MCF-7 (breast adenocarcinoma) human cell lines and against normal Vero cells (African green monkey kidney) with IC50 values ranging from 1.4 to 45.8 microg/mL. Additionally, the essential oil presented a significant bactericidal effect against Bacillus cereus, while a moderate activity was observed against Staphylococcus epidermidis and Candida albicans.

Comparative study of the chemical composition of essential oils of five Tagetes species collected in Venezuela.

The leaves and inflorescences of five species of Tagetes, family Asteraceae, were collected from different locations in Mérida state, Venezuela, and their essential oils analyzed by GC and GC/MS. Several differences were observed in the composition of these oils, mainly regarding the major components, which for T. caracasana were trans-ocimenone (64.3%) and cis-tagetone (13.7%), and for T. erecta, piperitone (35.9%) and terpinolene (22.2%). High amounts of trans-anethole (87.5%) and estragole (10.7%) were observed in T. filifolia, while T. subulata essential oil contained terpinolene (26.0%), piperitenone (13.1%) and limonene (10.8%). For T. patula, two different oil samples were analyzed, leaves (TPL) and inflorescences (TPI). The TPL oil showed terpinolene (20.9%) and piperitenone (14.0%) as main components, while the TPI sample was composed mainly of beta-caryophyllene (23.7%), terpinolene (15.6%) and cis-beta-ocimene (15.5%).

Adulticide effect of Monticalia greenmaniana (Asteraceae) against Lutzomyia migonei (Diptera: Psychodidae).

Leishmaniasis is a public health problem that has been increasing year by year, with the further difficulty that an efficient control system is not available. Therefore, it is necessary to search for less contaminating and dangerous alternatives for controlling Leishmania transmitting sandflies. The purpose of this study was to evaluate the activity of Monticalia greenmaniana (Asteraceae) extracts and essential oil as an adulticide against Lutzomyia migonei (Diptera: Psychodidae) females, from a laboratory colony, in experimental conditions. Dry aerial parts of M. greenmaniana (Hieron) Jeffrey were used. Methanolic and aqueous extracts were prepared, and essential oil was obtained by hydrodistillation. Adulticide tests in pots, adulticide tests in cages, and knocked-down effects were determined. The results obtained demonstrated that methanolic and aqueous extracts produced adulticide activity. The essential oil from M. greenmaniana was proved to be the most toxic against L. migonei, with a 95 % death rate at a concentration of 0.01 mg/ml during a 1-h exposure. The essential oil showed a DL50 = 0.0050 and DL98 = 0.0066 mg/ml. The methanolic extract was DL50 = 0.130 and DL98 = 1.016 mg/ml, and the aqueous extract, DL50 = 0.487 and DL98 10.924 mg/ml. The knocked-down effect for the M. greenmaniana oil showed a KDTL50 = 48.6 and KDTL98 = 90.1 min. It was concluded that the essential oil from M. greenmaniana showed a strong insecticide effect against L. migonei females, which encourages us to continue these studies in search for control alternatives against sandflies.

Essential oil composition and antibacterial activity of Monticalia greenmaniana (Asteraceae).

The essential oils from fresh aerial parts of Monticalia greenmaniana (Hieron) C. Jeffrey (Asteraceae) collected in March, were analyzed by GC/MS. Oil yields (w/v) of 0.1% (flowers), 0.07%, (stems) and 0.1% (leaves) were obtained by hydrodistillation. Thirteen, sixteen and eighteen components, respectively, were identified by comparison of their mass spectra with those in the Wiley GC-MS Library data base. The major components of the flower and stem oils were 1-nonane (38.8% flowers; 33.5% stems), alpha-pinene (29.0% flowers; 14.8% stems) and germacrene D (15.6% flowers; 18.6% stems). However, in the leaf oil, germacrene D was observed at 50.7%, followed by beta-cedrene at 8.4%. The leaf essential oil showed a broad spectrum of antibacterial activity against the important human pathogenic Gram-positive and Gram-negative bacteria Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and Klebsiella pneumoniae (ATCC 25955) with MIC values ranging from 75 to 6000 ppm.

Revisión bibliográfica sobre la composición química y actividades farmacológicas del género Vismia (Guttiferae) / A review on the chemical composition and pharmacological activities of Vismia genus (Guttiferae)

Vismia genus is an important source of natural medicinal products, thus, information collected in this review is an attempt to cover the most recent developments in the ethnopharmacology, pharmacology and phytochemistry of this genus. Anthraquinones and other quinonoid derivates, terpenoids and volatile constituents have been reported as the major constituents isolated from different Vismia species. On the other hand, pharmacological studies carried out to date have revealed the variety of anti-plasmodium, antioxidant, antimicrobial and antifungical properties of extracts and pure isolated compounds of the different species tested. The information summarized in this paper intends to serve as a reference tool to practitioners in the fields of etnopharmacology and chemistry of natural products.

El género Vismia es una fuente importante de productos naturales medicinales, es por esto que la información reunida en la presente revisión cubre los estudios más recientes en la etnofarmacología, farmacología y fitoquímica de este género. Antraquinonas y otros derivados quinoides, terpenos y constituyentes volátiles han sido reportados como los compuestos mayormente aislados de las diferentes especies de Vismia. Por otro lado, los estudios farmacológicos realizados hasta los momentos muestran las diversas propiedades antiplasmodicas, antioxidantes, antimicrobianas y antifúngicas que presentan tanto los extractos como los compuestos puros aislados de las diferentes especies ensayadas. La información resumida en este documento intenta servir de material de apoyo para investigadores en los campos de la etnofarmacologia y la química de productos naturales.

Essential oil composition and antibacteral activity of Vismia baccifera fruits collected from Mérida, Venezuela.

The essential oil from the fruits of Vismia baccifera Triana & Planch. (Gutttiferae), collected in June 2009, was analyzed by GC/MS. A yield of 0.6% oil was obtained by hydrodistillation. Twenty-seven components were identified by comparison of their mass spectra with those in the Wiley GC-MS Library data base. The major components were trans-cadin-l1,4-diene (36.6%), cis-cadin-1,4-diene (18.8%) and beta-caryophyllene (11.9%). The essential oil showed a broad spectrum of antibacterial activity against the important human pathogenic Gram-positive and Gram-negative bacteria Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25992), Pseudomonas aeruginosa (ATCC 27853) and Klebsiella pneumoniae (ATCC 23357) with MIC values ranging from 9 to 37 microg/mL.

Essential oil composition of Vismia macrophylla leaves (Guttiferae).

The essential oil from Vismia macrophylla Kunth (Guttiferae) leaves, extracted by hydrodistillation, was analyzed by GC/MS. The oil obtained (yield 0.11%) contained twenty-eight compounds, which were identified from their retention indices and by comparison of their mass spectra with those in the Wiley GC-MS Library data base. The major components were beta-caryophyllene (20.1%), germacrene D (11.6%) and beta-elemene (7.0%).

Volatile compounds from Tagetes pusilla (Asteraceae) collected from the Venezuela Andes.

The essential oil from the leaves of Tagetes pusilla Kunth (Asteraceae) collected from Mérida, Venezuela, was analyzed by GC/MS. A yield of 0.38% oil was obtained by hydrodistillation. Only two components, trans-anethole and 4-allylanisole were identified by comparison of their mass spectra with those in the Wiley GC-MS Library data base.

Chemical composition of the essential oil of leaves and roots of Ottoa oenanthoides (Apiaceae) from Mérida, venezuela.

Essential oils extracted by hydrodistillation from leaves and roots of Ottoa oenanthoides Kunth (Apiaceae) were analyzed by GC/MS. The oils, obtained in yields of 0.10% and 0.66%, respectively, each contained four compounds, which were identified from their mass spectra and retention indices (RI). The major compound identified was 2-methoxy-8-methyl-1,4-naphthalindione (59.9% leaves, and 62.8%, roots), followed by 7-methoxy-1-naphthol (18.3% leaves and 17.3% roots), 2-naphthalenol (18.6% leaves and 15.0% roots), and 3-methoxy-2-naphthalenol (3.1% leaves and 2.1% roots). To the best of our knowledge, this is the first time that naphthalene derivatives have been reported for any species of the Apiaceae family.

Chemical composition and antibacterial activity of the essential oil of Monticalia andicola (Asteraceae) collected in Venezuela.

The essential oil from the leaves of Monticalia andicola Turcz., collected in November 2008, was analyzed by GC/MS. A yield of 0.15% oil was obtained by hydrodistillation. Thirty-six components were identified by comparison of their mass spectra with those in the Wiley GC-MS Library data base. The major components were alpha-pinene (19.6%), beta-pinene (10.5%), alpha-longipinene (6.5%), delta-3-carene (6.2%), cyperene (5.4%) and beta-phellandrene (5.2%). The antibacterial activity of the essential oil was evaluated against Gram- positive (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212) and Gram-negative (Escherichia coli ATCC 25992, Klebsiella pneumoniae ATCC 23357, Pseudomonas aeruginosa ATCC 27853) bacteria, using the disc diffusion agar method. The results showed a broad spectrum of activity with minimal inhibitory concentration (MIC) values ranging from 10 to 150 microg/mL.

The chemical composition of the essential oils of Euphorbia caracasana and E. cotinifolia (Euphorbiaceae) from Venezuela.

The essential oils from leaves of E. caracasana Boiss collected from Miyoi, Pueblo Llano, Mérida State at 1800 m above sea level and leaves of E. cotinifolia L collected from Manzano Alto-Ejido, Mérida State at 1520 m were analyzed by GC/MS. Beta-Caryophyllene (33.7 %), alpha-humulene (18.8 %) and aromadendrene (8.4 %) were the major constituents of E. caracasana oil, whereas those of E. cotinifolia oil were beta-caryophyllene (39.3 %), germacrene-D (21.5 %) and alpha-copaene (9.3 %).