Sample records for hexadecanoic acid
from WorldWideScience.org

Sample records 1 - 4 shown.



1

Constituintes químicos voláteis e não-voláteis de Moringa oleifera Lam., Moringaceae/ Volatile and non-volatile chemical constituents of Moringa oleifera Lam., Moringaceae

Barreto, Milena B.; Freitas, João Vito B. de; Silveira, Edilberto R.; Bezerra, Antônio Marcos E.; Nunes, Edson P.; Gramosa, Nilce V.
2009-12-01

Resumo em português O estudo fitoquímico do extrato etanólico das folhas de Moringa oleifera Lam., Moringaceae, resultou no isolamento dos derivados benzilnitrilas niazirina, niazirinina e 4-hidroxifenil-acetonitrila, enquanto que das cascas dos frutos somente o octacosano foi obtido. Os óleos essenciais das folhas, flores e frutos foram analisados por cromatografia gasosa acoplada a espectrometria de massa. Os constituintes principais identificados foram: fitol (21,6%) e timol (9,6%) nas (mais) folhas, octadecano (27,4%) e ácido hexadecanóico (18,4%) nas flores e docosano (32,7%) e tetracosano (24,0%) nos frutos. As estruturas dos compostos isolados foram identificadas a partir de técnicas espectroscópicas (RMN, IV e EM). A 4-hidroxifenil-acetonitrila está sendo citada pela primeira vez para o gênero Moringa e os óleos essenciais das flores e frutos estão sendo citados pela primeira vez para a espécie M. oleifera. Resumo em inglês Phytochemical analysis of the ethanol extract from leaves of Moringa oleifera Lam., Moringaceae, yield the benzylnitriles: niazirine, niazirinine and 4-hydroxyphenylacetonitrile, while of fruit shells only octacosane was isolated. The essential oils from leaves, flowers and fruits were examined by gas chromatography-mass spectrometry. The major constituents identified were: phytol (21.6%) and thymol (9.6%) in the leaves oil, octadecane (27.4%) and hexadecanoic acid (18.4% (mais) ) in the flowers oil, docosane (32.7%) and tetracosane (24.0%) in the fruits oil. The structures of all compounds were identified by spectroscopic analyses (NMR, IR and MS). 4-hydroxyphenylacetonitrile is reported for the first time to the Moringa genus and the essential oils of flowers and fruits are reported for the first time to the species M. oleifera.

Scientific Electronic Library Online (Portuguese)

2

Constituintes químicos de licania tomentosa Benth. (Chrysobalanaceae)/ Chemical constituents of Licania tomentosa Benth. (Chrysobalanaceae)

Castilho, Rachel Oliveira; Kaplan, Maria Auxiliadora Coelho
2008-01-01

Resumo em inglês This paper describes the chemical constituents isolated from leaves and fruits of Licania tomentosa Benth. The plant materials were successively extracted with hexane and methanol. From the extracts the following compounds were obtained: betulinic acid; licanolide, a new triterpene lactone; oleanolic acid, lupeol; palmitoleic and hexadecanoic acid; a mixture of stigmasterol and sitosterol; and a mixture of tormentic, ursolic and betulinic acid. The structures of the natural products were identified on the basis of spectral data.

Scientific Electronic Library Online (Portuguese)

3

Composição química da glândula abdominal da fêmea da mariposa Castnia licus (Drury) (Lepidoptera:Castniidae): possíveis feromônios e precursores/ Chemical composition from female pheromone gland of Castnia licus (Drury) (Lepidoptera: Castniidae)

Rebouças, Lúcia M. C.; Caraciolo, Maria do S. B.; Sant'Ana, Antônio E. G.; Pickett, John A.; Wadhams, Lester J.; Pow, Eleanor M.
1999-09-01

Resumo em inglês The hexane and methanolic extracts from pheromonal glands of Castnia licus (Drury) virgin females have been studied. Analyses by gas chromatography and mass spectrometry allowed us to determine the major constituents present in the hexane extract as n-alkanes C21 to C30, (Z)-9-hexadecenoic acid (C16), and (Z)-9-octadecenoic acid (C18) and hexadecanoic acid (C16). Aldehyds, alkenes and acetates were also detected in low concentrations in the extracts. Female pheromone glan (mais) ds were analysed for pheromone precursors using the methanolic extract. In addition to the compounds methyl hexadecanoate and methyl (Z)-9-octadecenoate, the glandular tissue contains a homologous series of methyl esters from C12 to C24. The hexane extract of the female abdomenal glands elicited activity from males in a behavioural bioassay.

Scientific Electronic Library Online (Portuguese)

4

Causas químicas de resistência de Lycopersicon peruvianum (L.) a Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)/ Chemical resistance of Lycopersicon peruvianum (L.) to Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

Suinaga, Fábio A.; Picanço, Marcelo; Jham, Gulab N.; Brommonschenkel, Sérgio H.
1999-06-01

Resumo em português Esta pesquisa foi conduzida em casa de vegetação na Universidade Federal de Viçosa e objetivou estudar a resistência dos acessos CNPH 101, 374 e 402 de Lycopersicon peruvianum a Tuta absoluta e as causas químicas dessa resistência. Os tratamentos foram as espécies de tomateiro Lycopersicon esculentum (cvs. Santa e IPA-5: padrões de suscetibilidade) e os acessos de L. peruvianum. Avaliaram-se o número de ovos / folha, de minas pequenas (comprimento (mais) ndes (comprimento > 0,5 cm) e a percentagem de folíolos minados por T. absoluta. Realizou-se extração hexânica nas folhas, e os extratos obtidos foram submetidos a cromatografia gasosa associada a espectrômetro de massa. Nos acessos de L. peruvianum contataram-se menores taxas de oviposição, percentagens de folíolos minados, números de minas pequenas e grandes de T. absoluta do que nas cultivares IPA-5 e Santa Clara. Foram detectados 69 picos nos cromatogramas do extrato hexânico das folhas com concentração relativa > a 10(6) íons x seg. Verificou-se efeito significativo (p Resumo em inglês The resistance of three accessions of Lycopersicon peruvianum (CNPH 101, 374 and 402) to Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and its chemical causes were studied. The trial was carried out in greenhouse in the Universidade Federal de Viçosa, with two susceptible tomato cultivars (Lycopersicon esculentum cvs. Santa Clara and IPA-5) and three accessions of L. peruvianum. The number of eggs per leaf, short leaf mines (length (mais) > 0.5 cm) and the percentage of mined leaflets by T. absoluta were evaluated. All hexanic extracts were analyzed with a gas chromatography-mass spectrometer (GC-MS). Accessions of L. peruvianum showed lower number of eggs per leaf, percentage of mined leaflets and number of leaf mines (small and big) than the susceptible cultivars (IPA-5 and Santa Clara). The total number of compounds in the chromatograms was 69, with relative concentrations > 10(6) ions x second. The effect between T. absoluta attack and relative concentrations of the compounds showed by the five peaks (28, 42, 46, 55 and 58) was significant (p

Scientific Electronic Library Online (Portuguese)