Essential Oil from the Leaves, Fruits and Twigs of Schinus terebinthifolius: Chemical Composition, Antioxidant and Antibacterial Potential.

Schinus terebinthifolius Raddi, popularly known as "Pink pepper", is a plant native to Brazil. The objective of this work was to analyze the chemical composition and the antioxidant and antibacterial potential of essential oils (EOs) from the leaves, fruits and twigs of S. terebinthifolius, aiming for their application in food safety. EOs were obtained by hydrodistillation and the chemical composition was determined by gas chromatography coupled to mass spectrometry. Phenolic compounds were quantified and antioxidant activity was evaluated using three different methods. The antibacterial activity was determined by the broth microdilution method against foodborne bacteria. In the chemical analysis, 22 compounds were identified in the leaves, 13 compounds in the fruits and 37 compounds in the twigs, revealing the presence of the main compounds germacrene D (12.04%, 15.78%, 20,41%), caryophyllene (15.97%, 3.12%, 11.73%), α-pinene (11.6%, 17.16%, 2.99%), ß-pinene (5.68%, 43.34%, 5.60%) and γ-gurjunene (16,85%, 3,15%) respectively. EOs showed better antioxidant potential using the ß-carotene/linoleic acid method with 40.74, 61.52 and 63.65% oxidation inhibition for leaves, fruits and twigs, respectively. The EO from the leaves showed greater antibacterial potential against Escherichia coli and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 0.62 mg mL-1, a value lower than the MIC of sodium nitrite (5.00 mg mL-1), the antimicrobial standard synthetic. The activities of pink pepper EOs suggest their potential as a biopreservative in foods.

Chemical Evaluation, Phytotoxic Potential, and In Silico Study of Essential Oils from Leaves of Guatteria schomburgkiana Mart. and Xylopia frutescens Aubl. (Annonaceae) from the Brazilian Amazon.

The essential oils (EOs) of Guatteria schomburgkiana (Gsch) and Xylopia frutescens (Xfru) (Annonaceae) were obtained by hydrodistillation, and their chemical composition was evaluated by gas chromatography-mass spectrometry (GC/MS). Herbicide activity was measured by analyzing the seed germination percentage and root and hypocotyl elongation of two invasive species: Mimosa pudica and Senna obtusifolia. The highest yield was obtained for the EO of Xfru (1.06%). The chemical composition of Gsch was characterized by the presence of the oxygenated sesquiterpenes spathulenol (22.40%) and caryophyllene oxide (14.70%). Regarding the EO of Xfru, the hydrocarbon monoterpenes α-pinene (35.73%) and ß-pinene (18.90%) were the components identified with the highest concentrations. The germination of seeds of S. obtusifolia (13.33 ± 5.77%) showed higher resistance than that of seeds of M. pudica (86.67 ± 5.77%). S. obtusifolia was also more sensitive to the EO of Xfru in terms of radicle (55.22 ± 2.72%) and hypocotyl (71.12 ± 3.80%) elongation, while M. pudica showed greater sensitivity to the EO of Gsch. To screen the herbicidal activity, the molecular docking study of the major and potent compounds was performed against 4-hydroxyphenylpyruvate dioxygenase (HPPD) protein. Results showed good binding affinities and attributed the strongest inhibitory activity to δ-cadinene for the target protein. This work contributes to the study of the herbicidal properties of the EOs of species of Annonaceae from the Amazon region.

Finding reliable methodology for optical rotation and correct predictions of (s)-methyloxirane and (1R,5R)-ß-pinene.

Theoretical calculations of optical rotation (OR), although important to predict absolute configurations (ACs) and corroborate experiments, require efficient methodology able to reproduce enantiomer specificity and real OR values. Also, troublesome molecules are recurring in the literature, such as (S)-methyloxirane and (1R,5R)-ß-pinene. This study evaluates DFT functionals B3LYP, CAM-B3LYP, ωB97X-D, M06-2X, and PBE0 considering basis sets aug-cc-pVDZ, aug-cc-pVTZ, 6-311++G(2d,p), and 6-311++G(3df,2p) in OR prediction of 42 rigid organic molecules assessing cases with wrong enantiomeric determination comparing to available experimental data at wavelengths 355, 589, and 633 nm. Functionals CAM-B3LYP and ωB97X-D with aug-cc-pVTZ are indicated here to reproduce experimental values more accurately considering fewer number of wrong AC predictions, normalized RMSD values below 0.70, and a good approximation to experimental values in hierarchical cluster analysis. Methyloxirane AC was reproduced in CAM-B3LYP and PBE0, with [α]355=6.94 for CAM-B3LYP/aug-cc-pVTZ close to experimental value [α]355=7.49±0.30 . Good results were found for AC of ß-pinene in M06-2X, CAM-B3LYP, and ωB97X-D while the latter in 6-311++G(3df,2p) obtained OR values of [α]589=3.44 and [α]689=4.20 close to experimental values [α]589=2.8 and [α]689=4.66±0.60 . The two molecules aforementioned are, for the first time, reported to give valid theoretical OR values in such simple methodologies. OR calculations were all performed after geometry optimization at the same level of theory, and analysis of different functional combinations for each step in ß-pinene showed it can interfere with AC prediction even in rigid molecules.

Essential oils from leaves of Vernonanthura montevidensis (Spreng.) H. Rob.: chemical profile and antimollicute potential.

Aiming to valorise the Atlantic Rainforest biodiversity in Santa Catarina, the chemical characterisation of the essential oils (EOs) from leaves of Vernonanthura montevidensis (Spreng.) H. Rob. is described for the first time. Fresh leaves collected in the year 2014 and 2015, were submitted to hydrodistillation to give pale blue EOs in yields of 0.21 and 0.19%, respectively. The EOs were characterised by GC-MS and GC-FID semi- and quantitative methods. The monoterpene ß-pinene was the major constituent in both samples reaching a maximum of 26.3%. The monoterpene α-pinene and the sesquiterpene ß-caryophyllene, were also among the major constituents in both samples. By means of the extracted ion chromatogram procedure, it was possible to detect chamazulene, which was associated with the pale blue colour of the essential oils. In the in vitro antimollicute assays, the essential oil was moderately active against Mycoplasma genitalium and M. pneumoniae with MIC values of 250 µg mL-1.

Anthelmintic effect of essential rhizome oil from Hedychium coronarium Koenig (Zingiberaceae) introduced in Northeastern Brazil.

Hedychium coronarium is native to Tropical Asia and has been introduced into several Brazilian biomes. Significant biological properties described for the essential oil (EO) from this species' rhizomes include antimicrobial, larvicidal, anti-inflammatory, antioxidant, phytotoxic, and anthelmintic activities. The primary constituents identified in this study by GC-MS in the EO were monoterpenes 1,8-cineole (33.5%), ß-pinene (17.0%), α-terpineol (7.7%), α-pinene (7.3%), limonene (5.2%), and p-cymene (4.9%), comprising 75.6% of total oil compounds. The main monoterpenes' EO and standards were tested against N2 (susceptible) and UVR15 (resistant) adult nematode Caenorhabditis elegans strains, with varying dead rates in motility tests.. Nematocidal activity was not attributed to 1,8-cineole and ß-pinene, the main H. coronarium rhizome oil components, as both exhibited an inhibitory concentration (IC50) ≥ 5 mg/mL. On the other hand, the α-pinene (IC50, 1.69 mg/mL) and (S)-(-)-limonene (IC50, 1.66 mg/mL) standards demonstrated more efficient action than rhizome oil in motility tests, with significant adult C. elegans nematode mortality rates. These results support the hypothesis that the combination of H. coronarium EO constituents can be helpful as a nematicidal product, due to their synergistic action.

Turpentine valorization by its oxyfunctionalization to nopol through heterogeneous catalysis.

Turpentine is a mixture of monoterpene hydrocarbons obtained as a by-product in the paper industry. In this contribution we present its transformation process towards an alcohol named nopol, that is an important household product and fragrance raw material. Reaction conditions were established for the oxyfuntionalization of crude turpentine oil over Sn-MCM-41 catalyst for the selective conversion of ß-pinene to nopol. Synthesized materials were characterized by XRD, N2 adsorption, FT-IR, TEM and chemical absorption. The reaction was tested in 2 mL glass reactor with a sample of commercial turpentine with α-pinene (55.5% w/w) and ß-pinene (39.5% w/w) as main components and scaled up into a 100 mL Parr reactor, getting 92% conversion of ß-pinene and a nopol selectivity of 93%. The reusability tests showed that the catalyst can be reused 4 times without loss of activity. The results showed that 86% less solvent and 37.5% less paraformaldehyde can be used with turpentine, compared to the conditions used with ß-pinene for getting similar catalysts activity.

Wild Brazilian species of Eugenia genera (Myrtaceae) as an innovation hotspot for food and pharmacological purposes.

The Myrtaceae is one of the most common plant families in Brazil, including >1000 species of native fruit spread from North to South, where around 50% of all species are endemic to the Atlantic Rain Forest Biome. Most Brazilian species belong to Eugenia, Campomanesia, Psidium and Myrciaria genera. In general, they are characterized by the presence of leaves opposite, simple, entire, with pellucid glands containing ethereal oils and produces berry-like, fleshy fruits with a wide diversity of beneficial characteristics. Several parts of these plants are widely used in regional folk medicine as an astringent, anti-inflammatory, antihypertensive, to treat gastrointestinal disorders, and so on. Some species have already been studied and most of their metabolic effects are attributed to the presence of polyphenols, carotenoids as well as sesquiterpenes and monoterpenes. In addition, the Myrtaceae family has great economic potential, because of the sensory characteristics which encourages their commercial exploitation plus the presence of phytochemicals which play an important role in managing several degenerative chronic diseases besides representing a hotspot of technological innovation for food, cosmetic and pharmaceutical purposes. In this context, this review discusses about the importance of some Eugenia genera representatives such as Eugenia uniflora, Eugenia stipitata, Eugenia brasiliensis, Eugenia pyriformis and Eugenia dysenterica, emphasizing its profile of bioactive compounds as well as the knowledge of the nutritional and functional fruit potential, providing information for further studies aiming to stimulate the cultivation of Brazilian wild berries, for consumption and new food ingredients.

Comparative study of alpha- and beta-pinene effect on PTZ-induced convulsions in mice.

Convulsions occur in response to a loss of balance between excitatory and inhibitory neurotransmitters, and the treatment for this condition consists in restore such lost balance. Many anticonvulsant drugs present side effects which may limit their use. This fact has stimulated the search for new sources of treatment from aromatic plants. Many monoterpenes commonly present in essential oils are known because of their anticonvulsant properties. The anticonvulsant effect of α- and ß-pinene, two structural isomers, is still little studied. Thus, the present work evaluated the anticonvulsant effect of α- and ß-pinene in pentylenetetrazole-induced convulsions model. Initially, the oral LD50 for α- and ß-pinene was estimated. Following the oral administration, a mild sedation was observed and no deaths were recorded; the LD50 estimated for both monoterpenes was greater than 2 000 mg/kg, p.o. Further, animals were orally treated with α-pinene (100, 200 and 400 mg/kg), ß-pinene (100, 200 and 400 mg/kg) and the equimolar mixture of α- and ß-pinene (400 mg/kg) and subjected to the pentylenetetrazole-induced convulsions model. In this model, only the dose of 400 mg/kg of the compounds was able to significantly decrease the seizure intensity. The latency of first convulsion was significantly increased by the mixture of α- and ß-pinene (400 mg/kg). In addition, ß-pinene and the mixture of the two monoterpenes, both at a dose of 400 mg/kg, significantly increased the time of death of animals. The treatment with ß-pinene and the equimolar mixture of the two monoterpenes significantly reduced hippocampal nitrite level and striatal content of dopamine (DA) and norepinephrine (NE). Taken together, the results suggest that α-pinene appears to be devoid of anticonvulsant action. This fact, however, seems to be dependent on the chemical structure of the compound, since pretreatment with the ß-pinene increased the time of death pf PTZ-treated mice, which seems to depend on the ability of the compound to reduce nitrite concentration and NE and DA content, during the pentylenetetrazole-induced seizure.

Composición química del aceite esencial de las hojas de Hedyosmum luteynii Todzia (Chloranthaceae)

El objetivo de este trabajo fue la caracterización química del aceite esencial de Hedyosmum luteynii, a partir de muestras recolectadas en el bosque natural Jacarón, cantón Colta, provincia de Chimborazo, Ecuador. El aceite esencial se extrajo por hidrodestilación; el análisis de la composicion se realizó mediante un cromatógrafo de gases acoplado a un espectrómetro de masas; la identificación de los componentes se realizó por comparación de sus espectros de masas y de los índices de Kováts reportados en la literatura. Se identificaron 28 compuestos, correspondientes al 98.62% del total de los constituyentes, siendo la mayoría monoterpenos hidrocarburos naturales (83.21%). Los constituyentes más abundantes fueron: α-felandreno (32.72%), α-pineno (13.20%), (Z)-β-ocimeno (10.99%), silvestreno (6.51%), biciclogermacreno (5.05%), 1.8-cineol (4.95%), (E)-β-ocimeno (3.88%) y germacreno D (3.20%). Es la primera vez que se reporta al silvestreno como un componente importante en el aceite esencial de una de las especies del genero Hedyosmum. Este resultado hace evidente una marcada diferencia en la composición química del aceite esencial de H. luteynii respecto a otras especies del género Hedyosmum.

In this work, essential oil of Hedyosmum luteynii is characterize from samples collected in the Jacarón natural forest, Colta, Chimborazo, Ecuador. The essential oil was extracted by hydrodistillation; analysis of the composition was carried out by gas chromatograph, coupled to a mass spectrometer; identification of the components was made by comparing their mass spectra and the Kováts indexes reported in the literature. Twenty-eight compounds were identified, 98.62% of the total components. Natural hydrocarbon monoterpenes were the highger (83.21%). The most abundant components were: α-phellandrene (32.72%), α-pinene (13.20%), (Z)-β-ocimene (10.99%), silvestrene (6.51%), bicyclogermacrene (5.05%), 1.8-cineol (4.95%), (E)-β-ocimene (3.88%) and germacrene D (3.20%). For first time, silvestrene is reported as an important component of essential oil in one of the species of the genus Hedyosmum. This result is a important difference in the chemical composition of the essential oil of H. luteynii respect to other species of Hedyosmum.