Seasonal chemical compositions of the essential oils of Twoeugenia species and their acaricidal properties

The leaf essential oils of Eugenia lutescens Cambess andEugenia langsdorffii O. Berg, collected in the rainy (RS) and dry seasons (DS), were extracted by hydrodistillation and then characterized by a gas chromatography-flame ionization detector and a gas chromatography-mass spectrometer. The potential acaricidal activity and oviposition deterrence of these oils were evaluated against Tetranychus urticae . The oil yields were higher in the RS for E. lutescens, while those forE. langsdorffii were higher in the DS. α-Pinene and β-pinene were determined to be the major constituents of the oils fromE. lutescens, while bicyclogermacrene, spathulenol, and β-caryophyllene predominated in E. langsdorffii . Seasonal variations in the oils were primarily related to chemical diversity, and E. lutescens was more affected than was E. langsdorffii . The E. langsdorffii oil collected in the DS was most toxic to the spider mite, while the oils of E. lutescens and E. langsdorffii collected in the RS drastically reduced its egg quantities. This study successfully determined the periods of greater oil production and acaricidal activity

Chemical compositions of essential oil of piper species from atlantic forest of Amazonia, Brazil

Essential oils from the leaves of Piper japurense (Miq.) C. DC., P. coariense Yunk., P. auriculifolium Yunk., P. curtistilum C.DC., P. alatipetiolatum Yunk. and P. brevesanum Yunk. from the Amazon Forest (Brazil) were obtained through hydrodistillation. The chemical composition of the oils was determined using gas chromatography and mass spectrometry, which revealed the presence of 108 compounds representing 95.14%, 95.64%, 95.57%, 92.05%, 96.24% and 91.316% of the oils, respectively. All oils had an abundance of sesquiterpenes, except the oil from P. alatipetiolatum, which had a higher percentage of monoterpenes. The major components were α-eudesmol in the P. japurense (22.05%) and P. coariense (27.33%) oils, premnaspirodiene (32.26%) in the P. auriculifolium oil, caryophyllene oxide (28.69%) in the P. curtistilum oil, linalool (43.88%) in the P. alatipetiolatum oil and β-elemene (12.75%) in the P. brevesanum oil. Although the oils were composed of terpenes, the chemical analysis revealed qualitative and quantitative differences. This is the first report of the chemical composition of these six species of Piper that occur in the Amazonia biome in Brazil. © 2019 ACG Publications. All rights reserved

Evaluation of the insecticidal potential of leaf extracts of Anadenanthera colubrina var. cebil (Griseb) Altschul against Tetranychus urticae Koch and Sitophilus zeamais Mots

The deterioration and degradation of crops by insects causes economic losses of several billion dollars and affects food security. Sitophilus zeamais and Tetranychus urticae are two economically important species of agricultural crops around the world. The high toxicity of synthetic insecticides and the development of insect resistance to currently used chemicals stimulate the investigation of plant-derived insecticides as new alternatives for pest control. The insecticidal properties of secondary metabolites have been recognized, and have been confirmed scientifically in the last decades. The extract in cyclohexane (Ch) and ethyl acetate (Ea) of the leaves of Anadenanthera colubrina var. cebil collected in the dry and rainy seasons were evaluated for the survival and nutritional physiology of S. zeamais (maize weevil) and for the acaricidal effect front T. urticae (two-spotted spider). All extracts induced mortality of S. zeamais; however, only cyclohexane dry season (Chd) and ethyl acetate in the rainy season (Ear) caused significant mortality (p <0.05), more than 50%, promoting physiological damage to insects in all concentrations tested. In the mortality tests with the spider mite, extracts Chd and Ear showed an LC50 of 52.75 and 156.42 mg.mL-1. Still, in the same test, it can be observed that oviposition was also susceptible to extracts. Therefore, the extracts of A. colubrina are a source of compounds capable of interfering with and impairing the metabolism of the two studied pests

Caracterização fitoquímica e avaliação do potencial acaricida e inseticida do óleo essencial de Hymeneae courbaril L. var. courbaril sobre o ácaro-rajado e o gorgulho do milho

As propriedades inseticidas dos óleos essenciais são geralmente reconhecidas ao longo dos séculos e confirmadas cientificamente nas últimas décadas. Tais produtos podem ser usados na agricultura como uma alternativa para o controle de pragas. O óleo essencial derivado das folhas de Hymenaea courbaril L. var. courbaril foi obtido por hidrodestilação com arraste a vapor e caracterizado fitoquimicamente por cromatografia gasosa/espectrometria de massa (CG/EM); seu potencial acaricida e inseticida foi avaliado contra Tetranychus urticae e Sitophilus zeamais, respectivamente, pragas que ocorrem em uma ampla variedade de culturas economicamente importantes em todo o mundo. Após a análise por CG/EM, foram identificados 36 compostos, sendo 46,42% dos monoterpenos e 51,41% dos sesquiterpenos. Os bioensaios inseticidas avaliaram a interferência do óleo essencial na fisiologia nutricional do gorgulho e no processo de fumigação do ácaro. Os ensaios indicaram que o óleo essencial causou uma mortalidade significativa, promovendo danos fisiológicos ao S. zeamais. O valor de CL50 para T. urticae foi de 35,57 ?L/mL de ar; além disso, também foi observado que a oviposição foi afetada negativamente pelo óleo essencial. O óleo essencial de H. courbaril demonstrou ser um potencial controle de pragas por afetar o metabolismo e a reprodução de ambas as espécies de praga testadas

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http://dx.doi.org/10.5007/2175-7925.2008v21n4p39O “Tratado Único da Constituição Pestilencial de Pernambuco” de João Ferreyra da Rosa, publicado em 1694, foi o primeiro documento sobre a febre amarela, seus sintomas, tratamento e fitoterapia utilizada na época. Rosa descreveu uma centena de plantas medicinais aplicadas no combate à epidemia, destas, grande parte já vinha preparada do Reino, pois os médicos portugueses, em sua grande maioria, rejeitavam os conhecimentos fitoterápicos indígenas. Só mais tarde, devido à duração da viagem marítima e possível perda da eficácia dos princípios ativos, devido à sua degradação pela ação de altas temperaturas, umidade e forma de acondicionamento inadequada dos produtos fitoterápicos, é que esses médicos foram obrigados a adotar as plantas medicinais nativas na sua terapêutica. Dessa forma, as plantas medicinais brasileiras empregadas no tratamento da primeira epidemia de febre amarela no Brasil (século XVII) foram atualizadas do ponto de vista taxonômico fazendo-se comparações com as empregadas atualmente pela medicina popular para outros fi ns terapêuticos. Como resultado, no tratamento fitoterápico para debelar a febre amarela, no final do Séc XVII, Rosa fez uso das plantas medicinais brasileiras: copaíba, macela, maracujá-mirim, aroeira-vermelha, angelicó e almécega.Brazilian medicinal plants used by the Dr. João Ferreyra da Rosa according to his “Treatise on Pestilence in Pernambuco” at the end of the 17th century. João Ferreyra da Rosa’s “Treatise on Pestilencein Pernambuco”, published in 1694 was the fi rst document on yellow fever, its symptoms and treatment, and it described the phytomedicines used at the time. Rosa described a hundred medicinal plants used to treat the epidemic; most of them came already prepared from Europe, since the majority of Portuguese physicians rejected the indigenous therapeutic knowledge. However, later, due to the lenght and adverse conditions of maritime trevel, leading to losses in the effectiveness of the active ingredients of such phytotherapeutic products, doctors were obliged to employ native medicinal plants in their treatments. The Brazilian medicinal plants used in the treatment of the fi rst epidemic of yellow fever in Brazil (17th century) had been brought up to date from the taxonomic point of view, and were comparable with those used in popular medicine today. As part of the phytotherapeutic treatment of yellow fever at the end of the 17th century, Rose made use of thefollowing medicinal plants: copaíba, macela, maracujá-mirim, red aroeira, angélico and almécega