Composition of the essential oil from leaves of Smallanthus quichensis (Asteraceae) from Costa Rica / Composición química del aceite esencial de las hojas de Smallanthus quichensis (Asteraceae) de Costa Rica

Smallanthus is a genus of flowering plants in the Asteraceae family, which has about 24 species, ranging mostly from southern Mexico and Central America to the Andes in South America. The aim of the present study was to identify the chemical composition of leaf essential oil of S. quichensis, growing wild in Costa Rica. The extraction of the oils was carried out by the hydrodistillation method, using a modified Clevenger type apparatus. The chemical composition of the oils was analyzed by capillary GC-FID and GC-MS using the retention indices on DB-5 type capillary column. A total of 100 compounds were identified, accounting for about 90 percent of the total amount of the oils. Smallanthus quichensis leaf produced a monoterpenoid-rich oil, whose composition was dominated by αlfa-pinene (64.5 percent) and 1,8-cineole (9.7 percent) or, in a different sample, by αlfa-pinene (35.5 percent) with moderate amounts of p-cymene (11.5 percent), beta-phellandrene (9.2 percent), alfa-phellandrene (9.0 percent) and limonene (5.8 percent). This is the first report of the chemical composition of the essential oil obtained from this plant species.

Smallanthus es un género de plantas perteneciente a la familia Asteraceae que contiene aproximadamente 24 especies, la mayoría ubicadas desde el sur de México, América Central y hasta la cordillera de los Andes en América del Sur. El objetivo del presente estudio fue el de identificar la composición química del aceite esencial de las hojas de S. quichensis. La extracción se realizó mediante el método de hidrodestilación, empleando un instrumento de tipo Clevenger. Se analizó la composición de los aceites mediante CG-FID y CG-EM, utilizando índices de retención obtenidos en una columna capilar tipo DB-5. Se identificaron 100 compuestos, correspondientes a un 90 por ciento de los constituyentes totales. Los aceites están constituidos principalmente por monoterpenoides (ca. 85 por ciento). Los componentes mayoritarios se identificaron como alfa-pineno (64.5 por ciento), acompañado por 1,8-cineol (9.7 por ciento) o, en otra muestra distinta, αlfa-pineno (35.5 por ciento) junto a cantidades moderadas de p-cimeno (11.5 por ciento), beta-felandreno (9.2 por ciento), alfa-felandreno (9.0 por ciento) y limoneno (5.8 por ciento). Este es el primer informe acerca de la composición química de aceites esenciales obtenidos de S. quichensis.

Biotransformation of (-)-alpha-Pinene by Whole Cells of White Rot Fungi, Ceriporia sp. ZLY-2010 and Stereum hirsutum

Two white rot fungi, Ceriporia sp. ZLY-2010 (CER) and Stereum hirsutum (STH) were used as biocatalysts for the biotransformation of (-)-alpha-pinene. After 96 hr, CER converted the bicyclic monoterpene hydrocarbon (-)-alpha-pinene into alpha-terpineol (yield, 0.05 g/L), a monocyclic monoterpene alcohol, in addition to, other minor products. Using STH, verbenone was identified as the major biotransformed product, and minor products were myrtenol, camphor, and isopinocarveol. We did not observe any inhibitory effects of substrate or transformed products on mycelial growth of the fungi. The activities of fungal manganese-dependent peroxidase and laccase were monitored for 15 days to determine the enzymatic pathways related to the biotransformation of (-)-alpha-pinene. We concluded that a complex of enzymes, including intra- and extracellular enzymes, were involved in terpenoid biotransformation by white rot fungi.

Chemical composition and evaluation of antibacterial activity of essential oils of Ageratina jahnii and Ageratina pichinchensis collected in Mérida, Venezuela / Composición química y evaluación de la actividad antibacteriana de los aceites esenciales de Ageratina jahnii y Ageratina pichinchensis recolectadas en Mérida,Venezuela

Essential oil from leaves of Ageratina jahnii (B.L.Rob.) R. M. King & H. Rob. and Ageratina pichinchensis (Kunth) R. M. King & H. Rob (Asteraceae) collected in January 2010 were analyzed by GC/MS. Oils extracted by hydrodistillation yielded 0.50 percent and 0.43 percent w/v, respectively. Fifteen and twenty five components were identified by comparison of their mass spectra with the Wiley GC-MS Library data and by their retention indices (RI). The major components identified in A. jahnii were beta-myrcene (37.6 percent, alpha-pinene (17.1 percent), limonene (8.8 percent and pentacosane (9.2 percent while for A. pichinchensis 8,9-epoxythymyl isobutyrate (20.2 percent, germacrene-D (19.8 percent, thymyl isobutyrate (10.8 percent, eupatoriochromene (6.5 percent) and encecalol (5.9 percent) were observed as main compounds. This is the first report regarding the essential oil composition and antibacterial activity of the essential oil of A. jahnii.

Aceites esenciales de las hojas de Ageratina jahnii (B.L.Rob.) R. M. King & H. Rob. y Ageratina pichinchensis (Kunth) R. M. King & H. Rob (Asteraceae) colectadas en enero 2010 fueron analizados por CG/EM. Los aceites extraídos por hidrodestilación produjeron 0,50 por ciento y 0,43 por ciento p/v de rendimiento, respectivamente. Quince y veinticinco compuestos fueron identificados por comparación de sus espectros de masas con la base de datos de la librería Wiley CG/EM y por sus índices de retención (IR). Los compuestos identificados como majoritarios en A. jahnii fueron beta-mirceno (37,6 por ciento), alfa-pineno (17,1 por ciento, limoneno (8.8 por ciento y pentacosano (9,2 por ciento mientras para A. pichinchensis isobutirato de 8,9-epoxitimilo (20,2 por ciento, germacreno-D (19,8 por ciento, isobutirato de timilo (10,8 por ciento), eupatoriocromeno (6,5 por ciento y encecalol (5,9 por ciento) fueron observados como compuestos mayoritarios. Este es el primer reporte sobre la composición química y actividad antibacteriana del aceite esencial de A. jahnii.