- Laboratorio de Química Ecológica
Facultad de Ciencias - Universidad de Chile
Avenida Las Palmeras 3425, Ñuñoa, Santiago, Chile - +562 978 7266
- Universidad de Chile, Facultad de Ciencias, Post-Docadd
- Phytochemical Screening of Medicinal Plants, Pharmacognosy and Phytochemistry, Natural Products Chemistry, Chemical Ecology, Ethnopharmacology, Alkaloids, and 38 moreArchaeology, Organic Synthesis, Psychoactive Drugs, Anthropology of Hallucinogens, Entheogens, Psychedelics, Hallucinogens, Ethnobotany in South America, Indigenous ecological knowledges and practices, Andean archaeobotany, Clay Tobacco Pipes, Archaeology of Pipes and Smoking, Andean Archaeology, Burial Customs, Organic Residue Analysis, Analysis of dyes by gas chromatography-mass spectrometry (GC-MS), Indigenous Knowledge, Ceramics (Archaeology), Natural resin, Andean textiles, Archaeometry, Ceramic Analysis (Archaeology), Archaeological Method & Theory, Archaeological Science, Funerary Archaeology, Organic Chemistry, Periodo Formativo, Etnoarchaeology, Plantas aromaticas y medicinales, Plantas silvestres comestibles, Traditional Ecological Knowledge, Ethnobotany, Etnobotánica, Ethnobiology, Funerary Practices, Archaeology of Funerary Rituals, Ethnographic fieldwork, and Thibault Saintenoyedit
- I'm Chemist and degree in Chemistry (2006), and received my PhD in Chemistry at Facultad de Química y Biología, Unive... moreI'm Chemist and degree in Chemistry (2006), and received my PhD in Chemistry at Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), in Santiago Chile (2012). After this I moved to Universidad de Chile, Facultad de Ciencias, to work with Dr. Hermann Niemeyer to the present.
I am interested in the natural products chemistry, specifically in plant secondary metabolites of the native flora of Chile. Specifically my interest has focused on the search for diterpenes with antibacterial and antifungal, insecticidal essential oils, and alkaloids with psychoactive effects. Also my interest lately has focused on the ethnopharmacology of native flora from Northern Chile.
Currently, I work collaborate with scientists from different disciplines, institutions and countries to collaborate in the analysis of the biocultural evolution of pre-Hispanic populations from Atacama Oases.
In October 2012 I will start working on my first project FONDECYT (2013-2015): Exploration of the psychoactive potential of native flora from northern Chile in relation to its use in pre-Hispanic times.
Specialities:
Structural elucidation of secondary metabolites by 1D and 2D NMR and VCD. Research of secondary metabolites derivatives and essential oils of Chilean endemic terrestrial plants with antibacterial, antifungal and insecticide activities.
Ethnobotanical and Ethnopharmacological exploration of the psychoactive potential of native flora from northern Chile in relation to its use in pre-Hispanic times. Chemical analysis of bioarchaeological material (hair, textile, funerary paraphernalia and other devices).edit
A partir de un trabajo etnográfico centrado en las memorias territoriales de la comunidad aymara de Mulluri (Región de Arica y Parinacota, Norte de Chile) se propone que el pastoreo, un modo de vida tradicional de origen prehispánico,... more
A partir de un trabajo etnográfico centrado en las memorias territoriales de la comunidad aymara de Mulluri (Región de Arica y Parinacota, Norte de Chile) se propone que el pastoreo, un modo de vida tradicional de origen prehispánico, tiñe fuertemente la percepción del espacio de sus habitantes y la clasificación que elaboran en relación al mundo de las plantas. Se realizaron entrevistas y observación participante guiadas por un enfoque etnobotánico y espacial orientado a relevar sistemas clasificatorios y manejos ganaderos. Se analizaron las categorías “cordillera”, “costa” y “valle” usadas por los comuneros para nombrar las distintas regiones geográficas o pisos ecológicos de la gradiente occidental andina, definidas por ellos a partir de variables climáticas, ecológicas, simbólicas y prácticas. Simultáneamente, al interior de estas macro regiones los comuneros reconocen zonas específicas según las asociaciones botánicas existentes. Éstas fueron conceptualizadas por los comuneros como “etapas de pasto”, coincidiendo con los pisos vegetacionales definidos por la botánica. Y en relación a las plantas, se registraron categorías genéricas de acuerdo a sus formas de crecimiento (“pastos del champeal”, “pajas” o wichu, t ́olas, “montes”, “pastos de lluvia” y otros) así como nomenclaturas específicas por especie.
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En este artículo presentamos nuevos conocimientos sobre costumbres fumatorias en tres regiones geográficoculturales de Chile, en que las evidencias de prácticas de fumar en pipas se constatan, con cierto desfase cronológico, desde los... more
En este artículo presentamos nuevos conocimientos sobre costumbres fumatorias en tres regiones geográficoculturales de Chile, en que las evidencias de prácticas de fumar en pipas se constatan, con cierto desfase cronológico, desde los inicios del periodo Alfarero Temprano ca. 200 a.C., hasta el 1.300 d.C. El tema se abordó con una metodología multidisciplinaria que incluyó el estudio de los contextos de uso o depositación en que estos materiales fueron encontrados, los estilos morfo-tecnológicos y decorativos de los artefactos y análisis
arqueobotánico y químico de las sustancias fumadas. Los resultados obtenidos dan cuenta de dos relevantes y principales aspectos culturales vinculados al uso de artefactos para fumar. Uno de ellos fue constatar la existencia de una práctica generalizada de uso de pipas que involucró a distintos grupos culturales, en el trascurso del periodo Alfarero Temprano y en las tres regiones estudiadas. A su vez, bajo esta tradición suprarregional, se relevó la existencia de importantes particularidades regionales y/o locales. Estas se refieren a las diversas y
distintivas expresiones y atributos tecnológicos de los artefactos fumatorios, a la parafernalia asociada, a las diferencias cualitativas en cuanto a sitios y contextos en que fueron depositados estos artefactos y a los rangos de tiempo en que se mantuvieron vigentes estas prácticas.
arqueobotánico y químico de las sustancias fumadas. Los resultados obtenidos dan cuenta de dos relevantes y principales aspectos culturales vinculados al uso de artefactos para fumar. Uno de ellos fue constatar la existencia de una práctica generalizada de uso de pipas que involucró a distintos grupos culturales, en el trascurso del periodo Alfarero Temprano y en las tres regiones estudiadas. A su vez, bajo esta tradición suprarregional, se relevó la existencia de importantes particularidades regionales y/o locales. Estas se refieren a las diversas y
distintivas expresiones y atributos tecnológicos de los artefactos fumatorios, a la parafernalia asociada, a las diferencias cualitativas en cuanto a sitios y contextos en que fueron depositados estos artefactos y a los rangos de tiempo en que se mantuvieron vigentes estas prácticas.
Careful reevaluation of the 1H and 13C NMR spectroscopic data of filifolinol acetate (4) led to the reassignment of the C-10 and C-11 signals, as well as the gem-dimethyl signals. Single crystal X-ray analysis provided an independent... more
Careful reevaluation of the 1H and 13C NMR spectroscopic data of filifolinol acetate (4) led to the reassignment of the C-10 and C-11 signals, as well as the gem-dimethyl signals. Single crystal X-ray analysis provided an independent structural confirmation of 4, and comparison of the experimental vibrational circular dichroism spectrum with calculations performed using density functional theory provided the absolute configuration of this 3H-spiro-1-benzofuran-2,1′-cyclohexane and related molecules.
essential oils, ii) to determine the composition of the smoke generated by the combustion of different koas using a dynamic headspace sorption method for the collection of smoke samples, Plant-derived smoke is used in medicinal as well as... more
essential oils, ii) to determine the composition of the smoke generated by the combustion of different koas using a dynamic headspace sorption method for the collection of smoke samples, Plant-derived smoke is used in medicinal as well as ritual contexts by many cultures worldwide. These two aspects of smoke, pharmacological and cultural, can blend or intertwine, for example in the ancient use of tobacco as incense, medicine, and for religious purposes. Ethnographical studies in the Chilean Andean highlands have shown the use of a variety of aromatic plant species , generically denominated koas as incense or sahumerios by Atacameño and Aymara communities [1]. The koa concept in the central Andes integrates various aromatic and resinous bushes of the Asteraceae and Solanaceae whose smoke is used during certain ritual ceremonies. The aims of this work were: i) to establish the aromatic nature of the species by obtaining and analyzing their and to relate it to the pharmacological activ...
Several plant species are known to have been used in smoking practices by prehispanic inhabitants of central Chile. Archaeobotanical studies have shown the presence of seeds and plant microremains attributed to Datura sp. and Nicotiana... more
Several plant species are known to have been used in smoking practices by prehispanic inhabitants of central Chile. Archaeobotanical studies have shown the presence of seeds and plant microremains attributed to Datura sp. and Nicotiana sp., and chemical studies the presence of nicotine, both in residues of smoking pipes from various archaeological sites [1]. Besides the use of these psychoactive alkaloid-containing plant species, ethnohistorical and ethnographical studies have reported the use of species that act as adjuvants in the smoking practices [2 -3]. The purpose of these elements is unclear; they have been interpreted as conferring softening and flavouring characteristics, or otherwise enhancing the effect of alkaloidal and/or non-alkaloidal active compounds. The aims of this work were: i) to assess the aromatic nature of the species reported as adjuvants by obtaining and analyzing their essential oils; ii) to identify the components of the smok e generated by the combustion...
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Drastic cultural changes occurred during the Early Ceramic Period (200 BC–1300 AD) in Chile. The social systems became more complex, manifested by the appearance of a large variety of cultural expressions in archaeological contexts, among... more
Drastic cultural changes occurred during the Early Ceramic Period (200 BC–1300 AD) in Chile. The social systems became more complex, manifested by the appearance of a large variety of cultural expressions in archaeological contexts, among them smoking pipes or quitras. The spatial discontinuity of this evidence and the fragmentary state of the investigation of smoking pipes has limited our understanding of the Smoking Complex. We aim to deepen this understanding and widen our perspective by examining their contents and their social scope and dispersion. Our investigation uses evidence from the Smoking Complex at the La Granja site (central Chile), which has been associated with ritual ceremonies of local ceramic and horticultural groups as well as groups from nearby localities.
In this chapter, we present results obtained from the initial stage of our project. Analyses of archaeological seeds and residue analysis have been fundamental in the identification of plant species and substances consumed in the smoking pipes. The ethnohistorical and ethnographical data compiled, along with chemical and microfossil analyses, confirms the use of Nicotiana sp. in the pipes. Furthermore, the morphotechnological and stylistic studies have shown ample variability in the pipes from La Granja. In addition, the presence of other elements of smoking paraphernalia has augmented the types of material objects associated with this practice. Based on these results, we discuss this site as a place of social aggregation for communities living in the central region of Chile and how the analysis can enrich our understanding of the local Smoking Complex.
In this chapter, we present results obtained from the initial stage of our project. Analyses of archaeological seeds and residue analysis have been fundamental in the identification of plant species and substances consumed in the smoking pipes. The ethnohistorical and ethnographical data compiled, along with chemical and microfossil analyses, confirms the use of Nicotiana sp. in the pipes. Furthermore, the morphotechnological and stylistic studies have shown ample variability in the pipes from La Granja. In addition, the presence of other elements of smoking paraphernalia has augmented the types of material objects associated with this practice. Based on these results, we discuss this site as a place of social aggregation for communities living in the central region of Chile and how the analysis can enrich our understanding of the local Smoking Complex.
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La aplicación de marcadores en estudios arqueológicos es fundamental para obtener información de los materiales recuperados más allá de las meras descripciones morfotecnológicas. El uso de marcadores arqueobotánicos y químicos en el... more
La aplicación de marcadores en estudios arqueológicos es fundamental para obtener información de los
materiales recuperados más allá de las meras descripciones morfotecnológicas. El uso de marcadores arqueobotánicos
y químicos en el desarrollo del proyecto FONDECYT 1121097, “Los Complejos Fumatorios del Período
Alfarero Temprano en Chile semiárido y centro-sur: un estudio multidisciplinario”, redundó en la implementación
de un conjunto de requisitos para manipular objetos arqueológicos de modo tal de no perder la posibilidad de
obtener de ellos distintos marcadores, definidos y por definir, que conduzcan a diversos tipos de información.
Asuntos ligados al registro de procedencia y a la manipulación de los artefactos inciden directamente en la
potencialidad de analizar una muestra, por lo tanto, es necesario reformular los métodos de manipulación para
resguardar el estado original en que se encontraron las piezas a estudiar. En este trabajo, exponemos cómo el
uso de metodologías tomadas de diferentes disciplinas para la búsqueda de resultados diversos que apuntan a
la comprensión de una temática común, nos ha conducido a la proposición de un protocolo de manipulación
y toma de muestras.
materiales recuperados más allá de las meras descripciones morfotecnológicas. El uso de marcadores arqueobotánicos
y químicos en el desarrollo del proyecto FONDECYT 1121097, “Los Complejos Fumatorios del Período
Alfarero Temprano en Chile semiárido y centro-sur: un estudio multidisciplinario”, redundó en la implementación
de un conjunto de requisitos para manipular objetos arqueológicos de modo tal de no perder la posibilidad de
obtener de ellos distintos marcadores, definidos y por definir, que conduzcan a diversos tipos de información.
Asuntos ligados al registro de procedencia y a la manipulación de los artefactos inciden directamente en la
potencialidad de analizar una muestra, por lo tanto, es necesario reformular los métodos de manipulación para
resguardar el estado original en que se encontraron las piezas a estudiar. En este trabajo, exponemos cómo el
uso de metodologías tomadas de diferentes disciplinas para la búsqueda de resultados diversos que apuntan a
la comprensión de una temática común, nos ha conducido a la proposición de un protocolo de manipulación
y toma de muestras.
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El hallazgo de pipas en contextos fúnebres del litoral del Desierto de Atacama hace más de un siglo, ha sido la base para sugerir que los grupos de pescadores, cazadores y recolectores marinos tuvieron como costumbre fumar durante el... more
El hallazgo de pipas en contextos fúnebres del litoral del Desierto de Atacama hace más de un siglo, ha sido la base para sugerir que los grupos de pescadores, cazadores y recolectores marinos tuvieron como costumbre fumar durante el período Formativo (1500 a.C.–1000 cal d.C.). Lo que seguía siendo una incógnita es qué estaban fumando y de dónde provenían las sustancias consumidas. En la búsqueda de dar solución a este problema, presentamos el análisis de los residuos adheridos de cuatro pipas de piedra en forma de T invertida, recuperadas de un cementerio de la costa del Desierto de Atacama al norte de Chile, usando dos metodologías complementarias derivadas de la arqueobotánica y la química. Paralelamente, realizamos un análisis químico sobre cabello humano perteneciente a un individuo asociado a una de las pipas. Se logró identificar, al interior de éstas, la presencia de nicotina y otras sustancias, tales como microrrestos de Nicotiana y de otras especies, además de nicotina, en el cabello muestreado. Finalmente, discutimos estos resultados en función de la disponibilidad de fuentes de estos recursos, estrategias de movilidad, relaciones de intercambio y el modo de vida de las poblaciones litorales.
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Conditions for the use of archaeobotanical and chemical markers in archaeological research on smoking complexes: proposal for a protocol for artifact handling and sampling. The use of markers in archaeological studies is crucial to obtain... more
Conditions for the use of archaeobotanical and chemical markers in archaeological research on smoking complexes: proposal for a protocol for artifact handling and sampling. The use of markers in archaeological studies is crucial to obtain information about the materials recovered from archaeological sites, going beyond mere morpho-technological description. During the development of the FONDECYT 1121097 research project entitled "Los Complejos Fumatorios del Período Alfarero Temprano en Chile semiárido y centro-sur: un estudio multidisciplinario", a need emerged to implement a set of requirements concerning the collection, removal and treatment of archaeological objects in order to safeguard the possibility of studying different markers that may lead to various types of information. Matters related to the recording and handling of archaeological artifacts directly affect the potential to analyze a sample; therefore, it is necessary to check what basic requirements are needed and what manipulation methods are the most suitable to protect this evidence. The paper explains how the use of methodologies from different disciplenes oriented to respond to a common question has led to the proposal of a handling and sampling protocol.
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The consumption of plant-derived hallucinogenic substances through smoking and snuffing is a long-standing tradition in the south-central Andes. Chemical and archaeobotanical evidence point to the consumption of nicotine and tryptamine... more
The consumption of plant-derived hallucinogenic substances through smoking and snuffing is a long-standing tradition in the south-central Andes. Chemical and archaeobotanical evidence point to the consumption of nicotine and tryptamine alkaloids in Northwestern Argentina and of tryptamine alkaloids in San Pedro de Atacama (SPA), in prehispanic times. In this paper, results are reported of gas chromatography - mass spectrometry (GC/MS) analyses aimed at identifying nicotine and tryptamine alkaloids in the hair of mummies from different cultural periods of SPA. Fifty-six samples were examined. While tryptamines were not found in any of the samples, nicotine was found in 35 samples, assigned to the Late Formative (1 of 1 sample from this period), Late Formative or Middle (1 of 2 samples from either of these periods), Middle (4 of 6 samples from this period) and Late Intermediate periods (8 of 12 samples from this period), or without assignment to period due to lack of contextual information (21 of 35 samples unassigned to a period). These results show a continuous consumption of nicotine from the Late Formative to the Late Intermediate periods of SPA (ca. 100 B.C. – 1450 AD). No associations were found between presence of nicotine in the hair of mummies and presence of snuffing trays or of other snuffing paraphernalia in the corresponding tomb; furthermore, neither the diversity of the funerary context, measured in terms of the number of types of objects, nor the presence of gemstone necklaces differed between tombs with mummies with or without nicotine in their hair. Overall, these results suggest that consumption of nicotine was performed by members of the society at large, irrespective of their social and wealth status.
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In spite of the high degree of endemism of the native vascular flora of Chile (ca. 52%) and predictions based on the frequency of occurrence of alkaloids in the world flora (they have been found in 40.4% of the families, 13.1% of the... more
In spite of the high degree of endemism of the native vascular flora of Chile (ca. 52%) and predictions based on the frequency of occurrence of alkaloids in the world flora (they have been found in 40.4% of the families, 13.1% of the genera and 2.7% of the species), alkaloids have been isolated from only 12.5% of families, 3.9% of genera and 1.7% of species of the native flora of Chile. The slope of the linear correlation between these two sets of figures suggests that the alkaloid potential of the native Chilean flora has been exploited to the extent of only 29%. Currently known alkaloid-containing species from the native flora of Chile are listed in this review together with pertinent references. The distribution of alkaloids was compared between the native flora of Chile and the world flora; this led to the identification of several families with good potential as sources of alkaloids.
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The analysis by gas chromatography coupled with mass spectrometry (GC-MS) of the alkaloidal extract of Browningia candelaris (Cactaceae) showed the presence of N-acetyl-3,4-dimethoxyphenylethylamine;... more
The analysis by gas chromatography coupled with mass spectrometry (GC-MS) of the alkaloidal extract of Browningia candelaris (Cactaceae) showed the presence of N-acetyl-3,4-dimethoxyphenylethylamine; N,N-dimethyl-3,4-dimethoxyphenylethylamine; N,N-dimethyl-4-methoxyphenylethylamine; and 4-methoxyamphetamine. The presence of these psychoactive compounds is discussed in terms of their possible use in rituals in Andean cultures of northern Chile.
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A new withanolid amine was isolated from Dunalia spinosa (Solanaceae). Its relative stereochemistry was determined using FT-IR, 1H and 13C NMR spectroscopies and high resolution mass spectrometry. Nicotine was also isolated;... more
A new withanolid amine was isolated from Dunalia spinosa (Solanaceae). Its relative stereochemistry was determined using FT-IR, 1H and 13C NMR spectroscopies and high resolution mass spectrometry. Nicotine was also isolated; chemotaxonomic and archaeological implications are discussed.
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The floral volatile chemicals of four Heliotropium (Boraginaceae) species endemic to Chile are described and their relationship with an Heliotropium phylogeny assessed. Twenty-two compounds were identified; the most prominent family of... more
The floral volatile chemicals of four Heliotropium (Boraginaceae) species endemic to Chile are described and their relationship with an Heliotropium phylogeny assessed. Twenty-two compounds were identified; the most prominent family of compounds in H. floridum, H. myosotifolium and H. stenophyllum were benzenoids, and in H. pycnophyllum prominence of benzenoids was shared with two monoterpenes, (E)-Ocymene and 1,8-cineol. The similarity between chemical mixtures of the species significantly decreased with increasing phylogenetic distance between them. Neighbor-joining analysis produced a tree topology with one clade comprised by H. myosotifolium and H. stenophyllum and an unresolved relationship between this clade and H. floridum and H. pycnophyllum; this topology bears a close relationship with molecular phylogeny proposed for the group. These preliminary results presented suggest that the genus Heliotropium complies with the condition of phylogenetically-related floral scent interspecific variation, a key condition in studies of plant-pollinator coevolution mediated by them.
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The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Heliotropium stenophyllum (Heliotropiaceae) was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The... more
The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Heliotropium stenophyllum (Heliotropiaceae) was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The insecticidal activity of the oil against the house fly Musca domestica was evaluated and the dose necessary to kill 50% of flies (LC50) in 2 h was determined at 25 ± 1 °C. The essential oil from Heliotropium stenophyllum showed potent insecticidal properties (LC50 = 1.09 mg/dm3) in comparison with other essential oils, in which at shorter times, the same bio-assay was used. According to GC and GC/MS analysis, junenol (19.08%); longiborneol (9.34%); (E, Z)-geranyl linalool (6.81%); selina-3,11-dien-6-α-ol (6.70%); α-cedrene epoxide (6.60%); heliofolen-12-al D (6.23%) and β-epi-bisabolol (4.83%) were the principal components of the EO. The Heliotropium stenophyllum essential oil, made up exclusively of sesquiterpenes, showed a composition very different from the EOs of the other species of Heliotropium, studied, and present a great potential as a natural insecticide against houseflies.
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The relative stereochemistry at C13 and the absolute configuration of salvic acid, a constituent of the leaves of Eupatorium salvia, were established as the 13-(R)-ent-labdane 1. The results follow from vibrational circular dichroism... more
The relative stereochemistry at C13 and the absolute configuration of salvic acid, a constituent of the leaves of Eupatorium salvia, were established as the 13-(R)-ent-labdane 1. The results follow from vibrational circular dichroism measurements of the derived O-methyl ether methyl ester 3 which were compared to DFT B3LYP/DGDZVP calculated spectra. The relative stereochemistry of salvic acid at C13 was independently verified by single crystal X-ray diffraction measurements of 1, and of its derived diol 4.
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"The antibacterial properties of the resinous exudates from Haplopappus litoralis, H. chrysantemifolius and H. scrobiculatus from Central Chile were assessed against Gram negative and Gram-positive bacteria, and proved active against... more
"The antibacterial properties of the resinous exudates from Haplopappus litoralis, H. chrysantemifolius and H. scrobiculatus from Central Chile were assessed
against Gram negative and Gram-positive bacteria, and proved active against the latter. The results show that the antibacterial activities of the resinous
exudates are independent from the flavonols isolated from each extract that proved to be inactive. The estimated lipophilicity of the flavonols isolated from
the Haplopappus resinous exudates were compared with the lipophilicity of known antibacterial flavonols. This analysis showed that lipophilicity is an
important variable to predict the antibacterial activity of flavonols."
against Gram negative and Gram-positive bacteria, and proved active against the latter. The results show that the antibacterial activities of the resinous
exudates are independent from the flavonols isolated from each extract that proved to be inactive. The estimated lipophilicity of the flavonols isolated from
the Haplopappus resinous exudates were compared with the lipophilicity of known antibacterial flavonols. This analysis showed that lipophilicity is an
important variable to predict the antibacterial activity of flavonols."
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This communication reports the chemical composition of the light petroleum ether extract from the leaves and stems of Dunalia spinosa. The aerial part of D. spinosa was extracted using light petroleum ether, which on evaporation yielded a... more
This communication reports the chemical composition of the light petroleum ether extract from the leaves and stems of Dunalia spinosa. The aerial part of D. spinosa was extracted using light petroleum ether, which on evaporation yielded a residue. This residue was subsequently fractioned using CC chromatography on silica gel with petroleum ether, petroleum ether-CH2Cl2 gradient, CH2Cl2 and CH2Cl2-MeOH gradient. The fractions were analyzed using GC and GC-MS. A total of 34 compounds were identified accounting for 56.59% of the extracted mass. The unidentified compounds were isomers of branched chain alkanes and alkenes for which there were no documented compounds matching their calculated RI's. The following compounds were identified: n-Alkanes (65.88%) from C-14 to C-21 as the primary components. 1-Alkenes (1.15%): 1-tetradecene, 1-pentadecene, 1-hexadecene, 1- nonadecene. Aldehydes (1.29%): hexanal, nonanal and decanal. Monoterpenes (5.9%) sabinene, β-pinene, p-cymene, limonene, 1,8-cineol and 1.8-trans- sabinene. Sesquiterpenes (0.17%), caryophyllene oxide. Diterpenes (1.64%): Phytol. In addition, various compounds of note were identified, specifically pythone (4.98%), 7-oxabicyclo [4.1.0] heptane (5.85%) and methyl hexadecanoate (5.57%). This methodology is appropriate for the identification of complex compound mixtures in discarded fractions as in many phytochemical studies, these fractions provide a more complete profile of secondary metabolites in the studied species.
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The compositions of the essential oils (EO's) obtained by hydro distillation from fresh leaves of Haplopappus foliosus and Bahia ambrosoides was analyzed by gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of each... more
The compositions of the essential oils (EO's) obtained by hydro distillation from fresh leaves of Haplopappus foliosus and Bahia ambrosoides was analyzed by gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of each oil against the house fly Musca domestica was evaluated by placing flies in a glass jar with a screw cap that held a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC50) in 1 h was determined at 26±1°C. The essential oil from Haplopappus foliosus was the most potent insecticide (LC50= 4.43 mg/dm3), wile the EO from Bahia ambrosoides shows only moderated insecticide activity (LC50= 19.27 mg/dm3). Accordingto GC and GC/MS analysis, limonene (28,00%); epi-bicyclosesquiphellandrene (9,84%); bornyl acetate (7,74%); 4-terpineol (6,36%);p-cymene (6,00%); agarospirol (5,53%); α-muurolene (4,34%); δ-cadinene (3,98%) and caryophyllene (3,97%) were the principal components of Haplopappus foliosus EO and limonene (28,16%); α-pinene (11,12%); germacrene D (8,81%); sabinene (5,93%); α-thujene (3,48%); γ-curcumene (3,45%) y α-bergamotene (3,36%) were the principal components of Bahia ambrosoides EO. The EO from Haplopappus foliosus seem promising as a natural insecticide against houseflies and the difference with the activity of the EO of Bahia ambrosoides can be ascribed to the content of oxygenated monoterpenoids and sesquiterpenoids.
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The composition of the essential oils (EOs) obtained by hydro-distillation of fresh leaves from Pseudognaphalium robustum, P. heterotrichium and P. cheiranthifolium was analysed using gas chromatography/mass spectroscopy (GC-MS).... more
The composition of the essential oils (EOs) obtained by hydro-distillation of fresh leaves from Pseudognaphalium robustum, P. heterotrichium and P. cheiranthifolium was analysed using gas chromatography/mass spectroscopy (GC-MS). According to GC and GC-MS analysis, α-pinene (50.29 %), (E)-nerolidol (24.41 %) and 1,8-cineole (5.15 %) were the major components of Pseudognaphalium robustum essential oil. α-pinene (27.31 %), β-phellandrene (43.76 %) and criptone (5.88 %) were the major components of P. cheiranthifolium essential oil and β-phellandrene (24.34 %); α-pinene (17.19 %), germacrene B (13.56 %), spathulenol (7.42 %) and germacrene D (4.22 %) were the major components of P. heterotrichium essential oil. No essential oils were isolated from P. vira vira in which glandular trichomes are scarce. The considerable differences in the EO compositions of the Pseudognaphalium species found in this work support authors who consider Pseudognaphalium as a heterogeneous taxonomic group and propose its extensive revision.
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Epicuticular components were obtained using methylene chloride extraction of fresh leaves from two populations of Lithrea caustica. The methylene chloride extracts were analyzed using GC and GC-MS. The extracts from both sampled... more
Epicuticular components were obtained using methylene chloride extraction of fresh leaves from two populations of Lithrea caustica. The methylene chloride extracts were analyzed using GC and GC-MS. The extracts from both sampled populations showed a mixture of a hydrocarbon fraction of n-alkanes from C- 21 to C-33 as their main components and small amounts of monoterpene hydrocarbons. The allergen 3-(pentadec-10-enyl)-catechol was also identified in the epicuticular sample in very different proportions in both extracts. A second extract obtained after the epicuticle had been removed from the sample revealed oxygenated monoterpenes, sesquiterpene hydrocarbons and an increased amount of the allergen
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Careful reevaluation of the 1H and 13C NMR spectroscopic data of filifolinol acetate (4) led to the reassignment of the C-10 and C-11 signals, as well as the gem-dimethyl signals. Single crystal X-ray analysis provided an independent... more
Careful reevaluation of the 1H and 13C NMR spectroscopic data of filifolinol acetate (4) led to the reassignment of the C-10 and C-11 signals, as well as the gem-dimethyl signals. Single crystal X-ray analysis provided an independent structural confirmation of 4, and comparison of the experimental vibrational circular dichroism spectrum with calculations performed using density functional theory provided the absolute configuration of this 3H-spiro-1-benzofuran-2,1'-cyclohexane and related molecules.
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A re-examination of cuticular components of Heliotropium filifolium allowed the isolation of four new compounds: 3’-hydroxy-2’,2’,6’-trimethyl-3H-spiro[1-benzo- furan-2,1’-cyclohexane]-5-carboxylic acid (2), methyl... more
A re-examination of cuticular components of Heliotropium filifolium allowed the isolation of four new compounds: 3’-hydroxy-2’,2’,6’-trimethyl-3H-spiro[1-benzo- furan-2,1’-cyclohexane]-5-carboxylic acid (2), methyl 3’-acetyloxy-2’,2’,6’-trimethyl-3H- spiro[1-benzofuran-2,1’-cyclohexane]-5-carboxylate (3), methyl 3’-isopentanoyloxy- 2’,2’,6’-trimethyl-3H-spiro[1-benzofuran-2,1’-cyclohexane]-5-carboxylate (4) and methyl 3’-benzoyloxy-2’,2’,6’-trimethyl-3H-spiro[1-benzofuran-2,1’-cyclohexane]-5-carboxylate (5). Compounds 2-5 were identified by their spectroscopic analogies with filifolinol (1), and their structures confirmed by chemical correlation with 1. The antimicrobial properties of the compounds were tested against Gram positive and Gram negative bacteria. Some of them proved to be active against Gram positive, but inactive against Gram negative bacteria. In searching for structure-activity relationships from the obtained MIC values, lipophilicity was shown to be an important variable.
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The chemical compositions of the flower heads of H. bertedi and of Chrysantemum coronarium 1., visited by a varied entomofauna, were compared in the search of possible correlations that might explain why different plants are visited by... more
The chemical compositions of the flower heads of H. bertedi and of Chrysantemum coronarium 1., visited by a varied entomofauna, were compared in the search of possible correlations that might explain why different plants are visited by the same insects. Though some similarities were observed in the flavonoid contents of both species, their overall composition was dramatically different, pointing to the existence of rather complex mechanisms ofinsect attraction by these species. OUf results thus represent a cautionary remark to interpretations of such mechanisms based solely on the chemical composition of the volatile components offlowers in the field.
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The composition of essential oil (EO) from Schinus latifolius obtained by hydro distillation of dry leaves was analyzed using gas chromatography (GC-FID) and gas chromatography/mass spectroscopy (GC/MS). The insecticidal effect of the oil... more
The composition of essential oil (EO) from Schinus latifolius obtained by hydro distillation of dry leaves was analyzed using gas chromatography (GC-FID) and gas chromatography/mass spectroscopy (GC/MS). The insecticidal effect of the oil on the house fly Musca domestica was evaluated by placing flies in a sealed glass jar containing a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC50) in 0.5 and 1 h was determined at 26±1°C. The essential oil from Schinus latifolius showed significant insecticidal properties [LC50 = 31.98 mg/dm3 (0.5 h) and LC50 = 19.20 mg/dm3 (1 h)]. According to GC-FID and GC/MS analysis a total of 54 compounds were identified accounting for 99.45% of the EO, with limonene (50.23%); α-pinene (15.01%); β- pinene (11.81%); sabinene (4.71%) and α-thujene (2.18%) as the main components. The EO from Schinus latifolius appears promising as a natural insecticide against houseflies. The composition of the Schinus latifolius essential oil reported in this study is different to that reported in other publications. The most important characteristic is the high content of limonene (50.23%), which can be attributed to the time of year and the geographic location of the sampled plants.
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The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Peumus boldus was analyzed using gas chromatography (GC) and gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of the oil... more
The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Peumus boldus was analyzed using gas chromatography (GC) and gas chromatography/mass spectroscopy (GC/MS). The insecticidal activity of the oil against the house fly Musca domestica was evaluated by placing flies in a sealed glass jar containing a piece of EO-treated cotton yarn. The dose necessary to kill 50% of flies (LC50) in 1 h was determined at 26±1°C. The essential oil from Peumus boldus showed potent insecticidal properties (LC50 = 6.26 mg/dm3). According to GC and GC/MS analysis, 1,8-cineol (36.72%); p-cymene (26.79%); ascaridol (6.25%); sabinene (5.10%); 4-terpineol (4.39%); β-pinene (4.16%) and limonene (2.68%) were the principal components of the EO. The EO from Peumus boldus seems promising as a natural insecticide against houseflies. The peumus boldus essential oil reported in this paper is different to that reported in other publications. .The most important differences are the low content of ascaridol and the high content of both 1,8-cineol and p-cimene which can be attributed to the time of year and the geographic location of the samples plants.
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Surface compounds were obtained by a methylene chloride extraction of fresh flower heads of Flourensia thurifera. The methylene chloride extract was purified by column chromatography and analyzed by GC-MS, leading to the identification of... more
Surface compounds were obtained by a methylene chloride extraction of fresh flower heads of Flourensia thurifera. The methylene chloride extract was purified by column chromatography and analyzed by GC-MS, leading to the identification of several monoterpenes, sesquiterpenes and diterpenes. A hydrocarbon fraction of n-alkanes from C23 to C31 and C33 was also identified. Headspace analysis of the fresh flower heads was also carried out. Different proportions of the same mono- and some of the sesquiterpenes were identified in the volatile fraction. The presence of mono- and sesquiterpenes in the flower heads is in agreement with the fact that these families of compounds have been identified in other Flourensia species.