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Essential oils from the leaves of Bauhinia rufa and B. dumosa collected from the Cerrado biome in central Brazil were obtained by hydrodistillation and analyzed using GC and GC/MS. Both oil...

Essential oils from the leaves, stems, flowers and fruits of Melaleuca leucadendra growing in the state of Pernambuco, Brazil, were analyzed using gas chromatography-mass spectrometry (GC-MS). The effects of the oils and their major constituent were evaluated on the agricultural pests Tetranychus urticae and Plutella xylostella in different stages of development. The analysis revealed a M. leucadendra chemotype rich in (E)-nerolidol (81.78 ± 0.90 to 95.78 ± 1.20%). P. xylostella was more susceptible to the oils and major constituent than T. urticae. The fruit oil was 1.5-fold more toxic than the leaf oil to T. urticae eggs. (E)-Nerolidol was 5.5-fold and 4.5-fold more toxic to T. urticae adults than the leaf and fruit oils, respectively. Azamax® used as the positive control was more efficient than the oils and (E)-nerolidol against T. urticae. However, the oils and (E)-nerolidol were more toxic to P. xylostella than Azamax®.

This paper describes the construction of a polarimeter for the identification of chemical substances. The device was built with low-cost materials, measures the phenomenon of optical activity and has educational applicability. The measurement of optical activity is achieved through the measurement of the resulting polarized radiation in a photodiode connected to a voltmeter after passing through polarizing and analyzing filters.

Normal 0 21 false false false MicrosoftInternetExplorer4 Os oleos essenciais obtidos por hidrodestilacao das folhas e caules de Peperomia pellucida coletadas de um fragmento de Mata Atlântica no estado da Bahia, Brasil, foram analisados utilizando cromatografia gasosa e cromatografia gasosa-espectrometria de massa. Independentemente da parte da planta, sesquiterpenos foram a classe de compostos mais abundantes nos oleos, seguido de fenilpropanoides. Os principais constituintes do oleo das folhas foram ? -gurjuneno (11,34%), 1,10-di- epi -cubenol (11,27%), ( E )-cariofileno (8,71%) e dillapiole (8,50%), enquanto que carotol (9,77%), dillapiole (9,18%), trans - ? -guaieno (9,05%) e ( E )-cariofileno (8,53%) foram os principais constituintes do oleo de caule. A atividade dos oleos contra Tetranychus urticae foi avaliada por 24 h. O oleo do caule (LC 50 = 1 x 10 -2 µL/L of air) foi quatro vezes mais toxico do que o oleo de folha (LC 50 = 4 x 10 -2 µL/L of air), mas 2,5 vezes menos ativo do que o eugenol, o qual foi utilizado como o controle positivo .

Laboratory bioassays on fumigation, ovicidal and oviposition deterrence activity of the essential oil from Indigofera suffruticosa and its constituents [eugenol, (E)-asarone, dill apiole, (Z)-asarone, thymol, (E)-nerolidol and safrole] against Tetranychus urticae were carried out. Components of Indigofera leaf oil were characterized by gas chromatography (GC) ad mass spectrometry (GC-MS), which revealed the identification of 17 components, representing 97.7 ± 0.6% of the total oil, with a high percentage of phenylpropanoids (89.9 ± 0.5%), among which eugenol (45.6 ± 0.4%) and (E)-asarone (17.4 ± 0.2%) were major constituents. The ovicidal activity and oviposition deterrence tests revealed that the essential oil as well as its main compounds affected the oviposition and hatchability of mite eggs. Eugenol and thymol were the most potent compounds and were approximately 225-fold more potent than the oil. The acaricidal action exerted by sesquiterpenes and phenylpropanoids of the leaf oil is also discussed. The results suggest that the Indigofera oil and selected components associated with ovicidal activity and oviposition deterrence can serve as the basis for a promising agent that could be used in the formulation of a product for use against the T. urticae.

Chemical analysis involving gas chromatography coupled to mass spectrometry of the essential oils of red and orange flowers from E. velutina revealed a predominance of phenylpropanoids in both samples. However, qualitative and quantitative differences were found in the compositions. (E)-Asarone (16.22 ± 0.23%) and (E)-caryophyllene (12.22 ± 0.11%) were identified as the major constituents of the essential oil from the red flowers, whereas (E)-caryophyllene (41.72 ± 1.65%) and eugenol (20.99 ± 0.21%) were identified as the major constituents of the oil from the orange flowers. Seventeen fatty acids were characterized in the red and black seeds. The fatty acid composition in the two chromatic variations had a high degree of similarity. Oleic acid (41.56 ± 1.33% and 46.12 ± 1.90% in the red and black seeds, respectively), palmitic acid (15.39 ± 0.16% and 12.33 ± 0.41%) and behenic acid (9.95 ± 0.14% and 12.10 ± 0.42%) were identified as the main fatty acids. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) enabled identifying significant differences in the chemical profile of the essential oils from the red flower and orange flower varieties of E. velutina. In contrast, PCA and HCA analysis revealed no significant differences in the fatty acid profile of the red and black seeds.

The essential oils from leaves, stems and roots of Piper caldense were analyzed by GC-MS. The antibacterial potential of the oils was evaluated against gram-negative bacteria and gram-positive bacteria. The major chemical constituents that were identified from various parts of this plant were α-cardinal, α-muurolol, tujopsan-2-β-ol and δ-cadiene in the leaves, valencene, pentadecane, elina-3,7-11-dieno α-terpineol in the roots and terpine-4-ol, α-terpineol, α-cadinol 2-β-ol in the stems. Tissue oils showed antibacterial activity against the bacteria tested except for Enterococcus faecalis. This is the first report of the biological activity and chemical composition essential oil of P. caldense.

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.

The essential oils of Protium bahianum fruit and leaves obtained through water distillation were analyzed by GC-FID and GC/MS, and their acaricidal activity was also evaluated using Tetranychus urticae as model. Twenty-nine components were identifed in the oils. The main component of the fruit oil was α-pinene (34.0%) whereas aromadendrene (20.3%) was the major component of the leaf oil. The leaf oil exhibited a higher lethality rate with LC50 of 3.5 μL/L of air after 24 h exposure. The fruits oil showed LC50 of 9.1 μL/L of air and was repellent at 1% concentration.

The volatile components of the fruits from nine collections of Clusia nemorosa G. Mey. from two municipalities (Tamandare: T1–3 and Cabo de Santo Agostinho: N1–3; G1–3) of the coastal region of Pernambuco, Northeast of Brazil, in two kind of soil, rocky rich in iron (N1–3) and sandy clays (T1–3 and G1–3), were analyzed by GC and GC/MS. The isolated oils were obtained in similar yields, 0.1–0.3 % (w/w) and 0.1–0.2% (w/w) in the samples from Taman- dare (T1–3) and Fortress Nazare (N1–3) and in the samples from Gaibu (G1–3), respectively. The oil samples can be characterized by the abundance of sesquiterpene hydrocarbons, while the percentage of oxygenated sesquiterpenes was higher in the samples collected in Tamandare (T1–3: 20.4—22.0%) and Gaibu (G1–3: 17.6–20.4%). Monoterpenes hydrocarbons were totally absent in all samples. All samples showed β-caryophyllene (37.3–48.6%) as the principal component. Based on the information of other major components, two subtypes of C. nemorosa growing wild in Pe...

The essential oils of leaves and stems of Croton grewioides Baill. of the “agreste” region of Pernambuco, Brazil, were obtained by hydrodistillation and analyzed by GC and GC/MS. Twenty-two components were identified, which represented 99.8% and 98.6% of the total constituents in the leaf and stem oil, respectively. Croton grewioides produced an oil with a predominance of phenylpropanoid compounds, whose principal component was (E)-anethole (65.5% in the leaf and 47.8% in the stem). Other major components found in the leaf oil were methyl eugenol (10.6%) and (E)-methyl isoeugenol (4.7%). Other components identified in the stem oil were (E)-methyl isoeugenol (30.0%), cadalene (8.4%) and methyl eugenol (4.6%). The insecticidal activity of C. grewioides was evaluated against Mexican bean weevils, Zabrotes subfaciatus (Boheman) resulting in a LC50 for the leaf oil, which was 3.4 times less than that obtained from the stem oil.

The chemical compositions of the essential oils from the leaves collected of Lippia gracilis Schauer at two localities in the bioma caatinga of Pernambuco were analyzed by GC and GC/MS, where a total of thirty-six compounds were identified in the oils from all the samples. The chemical profiles of samples from the same locations were the same having only relative changes in composition. But the chemical compositions of oils collected in the vicinity of Buique in the Agreste of Pernambuco were quite different from the ones collected in Ouricuri in the Sertao. The main components identified in samples from Buique were carvacrol (36.4–45.0%) and p-cymene (18.1–26.2%), while thymol (37.4%), γ-terpinene (14.9–20.5%) and 4-methoxy-acetophenone (10.1–12.4%) were the major components found in the specimen collected in Buique.

Essential oils obtained by hydrodistillation from stem and leaves of Cordia globosa (Jacq.) Hmb., Bonpl. et Kunth and Cordia curassavica (Jacq.) Roem. et Schult. were analyzed by GC/FID and GC/MS. The oil yield of C. globosa and C. curassavica was 0.5% and 1.1% for the stem and 0.6% and 1.0% for the leaves, respectively. Although they belong to the same genus, the chemical composition of the oils from two Cordia species was very different. The main components in the oil of C. globosa were: 1-endo-bourbonanol (20.2% in stem) and linalyl butyrate (14.7% in stem); β-caryophyllene (39.0% in leaves) and α-humulene (12.1% in leaves). Spathulenol (27.1% in stem), trans-sesquisabinene hydrate (11.0% in stem), viridiflorol (10.7% in stem), β-phellandrene (25.3% in leaves), cubebol (23.9% in leaves) and α-pinene (10.4 % in leaves) were the main constituents of the oils of C. curassavica.

The essential oils from two sources of resinous exudates of Protium bahianum obtained by hydrodistillation were analyzed by combinations of GC and GC/MS. Twenty-two and thirteen components were identified in the oils from fresh and aged resins, comprising 95.8 % and 98.6 %, of the oils, respectively. The aged resin oil contained a high percentage of oxygen-containing sesquiterpenes (85.4 %) with a high predominance of β-(Z)-santalol acetate (83.1 %). In contrast, no sesquiterpenes were detected in the fresh resin oil and it was constituted basically by monoterpenes hydrocarbons (42.4 %) and oxygen-containing monoterpenes (27.7 %), of which α-phellandrene (13.9 %) and terpinen-4-ol (7.4 %) were the major components, respectively. The acaricidal activities against Tetranychus urticae of the resin oil were also investigated. Both oils showed fumigant toxicity (mortality and fecundity), but only the aged resin oil induced repellence.

The essential oils of Lantana camara L. and L. fucata Lindl. leaves collected in the region of Mata Serrana in the municipality of Brejo da Madre de Deus in Pernambuco—Brazil were obtained by hydrodistillation and analyzed by GC and GC/MS. Twenty-five compounds were identified in L. camara, representing 99.4% of the leaf oil constituents, while 15 compounds were identified in L. fucata, representing 97.1% of the leaf oil constituents. The major compounds present in the oil of L. fucata were caryophyllene oxide (27.9%), gossonorol (18.2%), β-caryophyllene (12.3%) and bulnesol (10.8%), whereas those in the oil of L. camara were germacrene D (28.6%), germacrene D-4-ol (19.9%), β-caryophyllene (16.2%) and bicyclogermacrene (14.7%).

The essential oil of the leaves of six samples of Piper aduncum L. growing wild in two different region of Pernambuco, northeast of Brazil (Brejo da Madre de Deus—samples BMD1—3 and Serra Negra—samples SN1—3), were investigated by a combinations of GC and GC/M S. The characterized oil samples from different localities show a high percentage of oxygen-containing sesquiterpenes in both places (BMD1—3: 90.1–90.8% and SN1—3: 95.6–97.5%). Oxygen-containing monoterpenes represented less than 6% in BMD1—3 and less than 1% in SN1—3. Twelve compounds were identified representing more than 95% of each of the oil samples. (E)-Nerolidol was found to be the main component in all the samples being present in BMD1—three in the range of 81.5 to 82.5% while in SN 1—3 79.2–81.2% were found. Despite the fact that some minor components are not present in each oil sample, this investigation showed the same compositions of the major components of the essential oils of these P. aduncum from different region of Pernanam...

Published in Khimiya Prirodnykh Soedinenii, No. 4, July–August, 2012, pp. 622–623. Original article submitted May 12, 2011.