ABSTRACT Linalool is the main compound of many essential oils and occurs in two isomeric forms: S-(+)- and R-(-)-linalool. This study aimed to determine if linalool isomers have different antimicrobial and anesthetic properties in fish. For this purpose, these compounds were previously isolated from Lippia alba (Mill.)N. E. Brown and Ocimum americanum L. essential oils. Antimicrobial effects were evaluated through the microdilution test against Aeromonas hydrophila, an important fish disease etiologic agent. Induction time until sedation, anesthesia and recovery time were determined in silver catfish (Rhamdia quelen) through bath exposure (60, 180, 300 or 500 μL L-1). The results showed different biological properties for the isomers being S-(+)-linalool the only active against A. hydrophila at 3.2 mg mL-1. The sedation was induced without differences between the compounds, however R-(-)-linalool promoted faster anesthesia. There were no differences regarding the recovery time of the animals exposed to the linalool isomers. Although both S-(+)- and R-(-)-linalool can be used for sedative purposes, their use in A. hydrophila infection is inadvisable due to the high effective concentration. Considering anesthesia as the main objective, the R-(-)-linalool demonstrated clear advantages at lower concentration.

Five sesquiterpenoid oxides, named nectandrene A, B, C, D, and E, were isolated from the essential oil of the leaves of Nectandra megapotamica. Their structures were elucidated by spectroscopic analysis, and the relative configurations were proposed by their nuclear Overhauser effect (NOESY) spectrum. Three of these isolated compounds displayed significant antimicrobial activity; the compound most active had minimal inhibitory concentration (MIC) values between 3.12 and 25.0 μg mL-1 against some tested bacteria, and antifungal activity with MIC values between 12.5 and 25.0 μg mL-1.

We herein described the preparation of a novel series of limonin derivatives (modification in A-ring), which was synthesized efficiently using methodology in solution as well as in heterogeneous medium (K-10). In addition, we obtained derivatives by inserting the 1,2,3-triazole nucleus via click reaction and also prepared derivatives from reactions with limonin-7-oxime. All compounds were submitted to investigation of the antimicrobial activity against a collection of microorganisms. The results of the antimicrobial activity, in general, demonstrated that a relevant number of synthetic derivatives presented higher activity than the natural product.

The essential oils obtained by hydrodistillation from samples of propolis manufactured in three regions of Rio Grande do Sul State at Brazil, were analyzed through CG, CG-MS and chiral phase gas chromatography (CPGC). These analyses display the presence of samples with elevated essential oil purport, when compared with plants. The yields obtained were until 3.8%. The samples exhibited similar composition, with predominance of the monoterpenes α-pinene (5763%), β-pinene (12.5-30.8%) and limonene (1.5-11.2%). In chiral analysis ofthese constituents were observed modifications in the enantiomeric excess of isomers of α-pinene and limonene in relation with source location of the sample, already in the chiral analysis of β-pinene were detected only elevated excess of the enantiomer with the (-) configuration. The antimicrobial activity of the crude essential oil was assayed against five bacteria. The best result was obtained against Staphylococcus aureus.

Neste trabalho uma nova fase estacionária quiral,heptaquis (3-O-pentafluoropropionil-2,6-di-O-pentil)-β-ciclodextrina, foi sintetizada e avaliada frente uma grande variedade de compostos voláteis quirais. O novo derivado de ciclodextrina foi usado para a separação de componentes de óleos essenciais, como hidrocarbonetos, cetonas, aldeídos, álcoois de cadeia longa, compostos halogenados e compostos contendo nitrogênio e enxofre.

In this work, a new chiral stationary phase heptakis (3-O-pentafluoropropionyl-2,6-di-O-pentyl)-β-cyclodextrin was synthesized and evaluated with a wide variety of volatile chiral compounds. As a result, the new cyclodextrin derivative can be applied to the separation of chiral components of essential oils, as hydrocarbons, ketones, aldehydes, alcohols and of various classes of synthetic chiral compounds, as long chain alcohols, halocarbons, nitrogen and sulfur containing compounds.

Os óleos essenciais de folhas de Poiretia latifolia Vogel nativas e cultivadas (amostras A e B, respectivamente) e de flores nativas (amostra C), foram obtidos por hidrodestilação e analisados por CG, CG/EM, e através de cromatografia gasosa em fase quiral (CGFQ). Vinte e quatro componentes foram identificados, representando 99,25, 99,26 e 99,23% dos óleos, respectivamente. Os maiores constituintes dos óleos foram os monoterpenos (S)-(-)-limoneno (16,05, 27,60, 15,60%, respectivamente), (1R, 4R)-trans-(+)-diidrocarvona (18,05, 0,66, 77,80%, respectivamente) e (R)-(-)-carvona (61,05, 64,20, 4,50%, respectivamente). Os óleos essenciais apresentaram uma atividade antimicrobiana moderada quando avaliados frente a bactérias e Gram-positivas, Gram-negativas e fungos

The essential oils of Poiretia latifolia Vogel, native and cultivated leaves (Samples A and B, respectively) and native flowers (sample C), were obtained by hydrodistillation and analyzed by GC, GC/MS and chiral phase gas chromatography (CPGC). Twenty-four compounds were identified, representing 99.25, 99.26 and 99.23% of the oils, respectively. The major constituents of the oils were the monoterpenes (S)-(-)-limonene (16.05, 27.60, 15.60%, respectively), (1R, 4R)-trans-(+)-dihydrocarvone (18.05, 0.66 and 77.80%, respectively) and (R)-(-)-carvone (61.05, 64.20 and 4.50%, respectively). The essential oils were evaluated against some strains of Gram (+) and Gram (-) bacteria, and yeast, but displayed only modest antimicrobial activity.

Uma série de cetonas e ésteres alfa,beta-insaturados b-amino ésteres, 4a-h e 6a-d, derivados de alfa-amino ácidos foi obtida a partir dos cloridratos dos alfa-amino ésteres 2a-d e dos compostos 1,3-dicarbonílicos 3a,b e 5 em presença de trietilamina. Estes compostos foram preparados empregando energia de microondas, sem uso de solvente, utilizando como suporte sólido K-10 ou KSF e também foram efetuadas reações na ausência de suporte sólido.

A series of beta-amino esters alpha,beta-unsaturated ketones and esters 4a-h and 6a-d derived from alpha-amino acids have been prepared starting from alpha-amino esters hydrochorides 2a-d with 1,3- dicarbonyl compounds 3a,b and 5 in presence of triethylamine. These compounds have been prepared under domestic microwave oven, under solvent free condition with and without solid support (K-10 or KSF).

Os óleos essenciais obtidos das partes aéreas de Aloysia sellowii, coletadas em duas diferentes localidades (A e B) do sul do Brasil, foram analisadas por CG, CG-EM, e através de cromatografia gasosa com fases quirais (CGC). Dos quarenta e oito componentes identificados, representando cerca de 93 e 91% dos óleos das regiões A e B, respectivamente, 1,8-cineol, beta-pineno, sabineno e beta-(Z)-santalol foram os principais componentes. Um "screening" preliminar das duas amostras de óleos de A. sellowii mostrou atividade frente a Artemia salina (LC50 = 2,85 µg mL-1), além de exibirem atividade antimicrobiana frente a bactérias Gram-positivas e Gram-negativas e frente a leveduras (MIC 1,7-16 mg mL-1).

The essential oils obtained from aerial parts of Aloysia sellowii from two different collection locations Southern Brazil (A and B), were analyzed by GC, GC/MS, and chiral phase gas chromatography (CPGC). It was identified 48 compounds representing ca 93% and 91% of the oils of samples A and B, respectively. Besides them 1,8-Cineole, beta-pinene, sabinene, and beta-(Z)-santalol were the major components. In a preliminary biological screening the samples of essential oils of A. sellowii displayed strong activity in the brine shrimp lethality assay (LC50 = 2.85 µg mL-1) as well as antimicrobial activity against Gram-positive and Gram-negative microorganisms and two yeasts (MIC 1.7-16 mg mL-1).