Milene Aparecida Andrade

Chemical Composition and Antioxidant Activity of Essential Oils from Cinnamodendron dinisii Schwacke and Siparuna guianensis Aublet

The objectives of this study were to chemically characterize and evaluate the antioxidant activity of essential oils Cinnamodendron dinisii Schwacke (pepper) and Siparuna guianensis Aublet (negramina). The essential oil was isolated by hydrodistillation using a Clevenger modified apparatus, and the identification and quantification of constituents, through GC/MS and GC-FID analysis. The antioxidant activity was evaluated using β-carotene/linoleic acid system and the DPPH radical sequestering method. In chromatographic analysis, the majority constituents found in the essential oil of C. dinisii were bicyclic monoterpenes, α-pinene (35.41%), β-pinene (17.81%), sabinene (12.01%) and sesquiterpene bicyclogermacrene (7.59%). In the essential oil of the fresh leaves of Siparuna guianensis Aublet, acyclic monoterpene, β-myrcene (13.14%), and sesquiterpenes, germacrene-D (8.68%) and bicyclogermacrene (16.71%) were identified. The antioxidant activity was low by the β-carotene/linoleic acid test and was not evidenced by the DPPH test, for both oils evaluated.

Composition of the essential oil from the leaves of tree domestic varieties and one wild variety of the guava plant (Psidium guajava L., Myrtaceae)

The compositions of the essential oils from the leaves of three domestic varieties of the guava tree Psidium guajava L. (Paluma, Seculo XXI and Pedro Sato) and of one wild variety were compared. Essential oils were extracted by steam distillation, the components were identified by gas chromatography coupled to mass spectrometry GC-MS, and the apparent concentrations were determined by gas chromatography with a flame ionization detector. The results demonstrated that the three essential oils contained many common substances with a prevalence of 1,8-cineole, whereas the essential oil of the Paluma variety contained 1,8-cineole (42.68%) as the major constituent, as well as α-terpineol (38.68%). The principal components of the essential oil of the Seculo XXI variety were 1,8-cineole (18.83%), trans-caryophyllene (12.08%), and selin-11-en-4-αol (20.98%), while those of the Pedro Sato variety and of the wild plant were 1,8-cineole (17.68%) and (12.83%), caryophyllene oxide (9.34%) and (9.09%), and selin-11-en-4-α-ol (21.46%) and (22.19%), respectively.

Essential oil of Origanum majorana L., Illicium verum Hook. f. and Cinnamomum zeylanicum Blume: chemical and antimicrobial characterization

Essential oils of Origanum majorana L. (marjoram), Illicium verum Hook. f. (star- anise) and Cinnamomum zeylanicum Blume (cinnamon) were obtained by steam distillation using a modified Clevenger device. The antimicrobial activity of each oil was evaluated against the bacteria Staphylococcus aureus, Escherichia coli and the fungi Aspergillus flavus and Aspergillus parasiticus by observing their growth and/or mycelial inhibition through comparison with the standard dish (without oil). The essential oils were analyzed using a gas chromatograph coupled to a mass spectrometer for identification and coupled to a flame ionization detector for quantification. The major constituents of marjoram, star-anise and cinnamon essential oils were 4-terpineol, trans- anetole and cinnamic aldehyde, respectively. In in vitro tests, essential oils of marjoram and cinnamon promoted an inhibitory effect on the bacteria S. aureus and E. coli, while the essential oil of star-anise presented activity only against E. coli. Marjoram, star-anise and cinnamon oils were effective against the studied fungi, presenting an inhibitory effect. The minimal inhibitory concentration for the mycelial growth of A. parasiticus was 1 and 0.01 L mL -1 for star-anise and cinnamon oils, respectively. The minimal inhibitory concentration for A. parasiticus was 0.25, 2 and 2 L mL -1 for cinnamon, star-anise and marjoram oils, respectively.

Biological activity of the essential oils from Cinnamodendron dinisii and Siparuna guianensis

This study had analyzed the antibacterial, antifungal and trypanocidal activity of the essential oils from Cinnamodendron dinisii Schwacke (Canellaceae) and Siparuna guianensis Aublet (Siparunaceae). The essential oils were obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. Chemical analysis by gas-liquid chromatography coupled to mass spectrometry (GC-MS) showed that these essential oils are rich in monoterpene and sesquiterpene hydrocarbons. Activity against the pathogenic bacteria Escherichia coli , Listeria monocytogenes , Pseudomonas aeruginosa , Salmonella choleraesuis and Staphylococcus aureus was evaluated with the agar cavity diffusion method, while activity on the filamentous fungi Aspergillus flavus , Aspergillus niger , Aspergillus carbonarius and Penicillium commune was evaluated by the disk diffusion technique. Trypanocidal activity was tested against Trypanosoma cruzi epimastigotes, using the Tetrazolium salt (MTT) colorimetric assay. Both essential oils exhibited low inhibitory effect towards bacteria, showing high MIC values (125–500 μg mL −1 ), with Gram positive bacteria being more susceptible. Better inhibitory effect was obtained for the evaluated fungi, with lower MIC values (7.81–250 μg mL −1 ), being A. flavus the most susceptible species. Both essential oils presented low trypanocidal activity, with IC 50 /24 h values of 209.30 μg mL −1 for S. guianensis and 282.93 μg mL −1 for C. dinisii . Thus, the high values observed for the MIC of evaluated bacteria and for IC 50 /24 h of T. cruzi , suggest that the essential oils have a low inhibitory activity against these microorganisms. In addition, the low MIC values observed for the tested fungi species indicate good inhibitory activity on these microorganisms’s growth.

Influência da secagem sobre o rendimento e composição química dos compostos voláteis das raízes de Piper piscatorum Trel. & Yunck. (Piperaceae)

In this study, we evaluated the yield and chemical composition of volatile compounds obtained from fresh, dried at 30 and 40 oC respectively of Piper piscatorum, employing the technique of hydrodistillation. The volatile were chemically characterized by GC-MS and GC-FID. The main volatile compounds were selin-11-en-4-a-ol (57,63 ± 3,07%; 53,95 ± 1,56% and 56,20 ± 0,43%) and benzyl benzoate (15,40 ± 0,36%; 16,32 ± 0,85% and 15,04 ± 0,24%).The drying of the raw material reduced yield of volatile compounds, changing their chemical compositions.

Chemical analyses of the essential oils from leaves of Mikania glauca Mart. ex Baker

The essential oils obtained by hydrodistillation of two samples of fresh Mikania glauca leaves collected in different periods were analyzed by gas chromatography (GC) and by GC–mass spectrometry (GC–MS). Twenty compounds, representing 99% of the total oil composition, were identified and quantified in sample 1, while forty-five compounds, also representing 99% of the total oil composition, were identified in sample 2. The essential oils from the fresh leaves of both samples were rich in the terpenes. In sample 1 and 2, respectively, α-pinene (27% and 26%), β-pinene (22% and 36%), myrcene (24% and 18%), β-caryophyllene (9% and 6%) and bicyclogermacrene (8% and 4%) were the principal constituents. This demonstrated the predominance of monoterpene hydrocarbons in the essential oil of M. glauca and the influence of the collection period on the concentrations of the components.

Anticancer Properties of Essential Oils: An Overview

BACKGROUND Essential oils are complex mixtures of low molecular weight compounds extracted from plants. Their main constituents are terpenes and phenylpropanoids, which are responsible for their biological and pharmaceutical properties, such as insecticidal, parasiticidal, antimicrobial, antioxidant, anti-inflammatory, analgesic, antinociceptive, anticarcinogenic, and antitumor properties. Cancer is a complex genetic disease considered as a serious public health problem worldwide, accounting for more than 8 million deaths annually. OBJECTIVE The activities of prevention and treatment of different types of cancer and the medicinal potential of essential oils are addressed in this review. CONCLUSION Several studies have demonstrated anti-carcinogenic and antitumor activity for many essential oils obtained from various plant species. They may be used as a substitution to or in addition to conventional anti-cancer therapy. Although many studies report possible mechanisms of action for essential oils compounds, more studies are necessary in order to apply them safely and appropriately in cancer therapy.

Influência da temperatura de secagem sobre o rendimento e a composição química do óleo essencial de Tanaecium nocturnum (barb. Rodr.) bur. & K. Shum

The yields and chemical compositions of the essential oils obtained by steam distillation of the fresh and dried (30 and 40 oC) leaves, stems and roots of Tanaecium nocturnum are reported. The identification and quantification of the volatile constituents were accomplished by GC/MS and GC/FID, respectively. The essential oils obtained from the various parts of the plant were constituted mainly of benzaldehyde. Large losses and variations in the quantities of the components during the drying process were observed. The presence of mandelonitrile in higher concentration in the stem and roots indicates that this species produces cyanogenic glycosides.