A análise fitoquímica das infusões das inflorescências de dois quimiotipos cultivados de Egletes viscosa Less foi realizada. O novo diterpeno 12-acetoxi-7-hidroxi-3,13(14)-clerodandieno-18,19:15,16-diolídeo, ternatina, ácido centipédico e a lactona do ácido 12-acetoxihawtriwaico foram isolados a partir do quimiotipo acetato de trans-pinocarveíla, enquanto que o quimiotipo acetato de cis-isopinocarveíla forneceu o 12-acetoxi-7-hidroxi-3,13(14)-clerodandieno-18,19:15,16-diolídeo, 12-epi-bacchotricuneatina, ternatina e escopoletina. A elucidação estrutural dos compostos isolados foi realizada com base em dados espectrais, através do uso de seqüências de pulsos de RMN uni e bidimensionais e comparação com dados da literatura.Phytochemical analysis of flower buds infusion from two cultivated chemotypes of Egletes viscosa Less was accomplished. The new diterpene 12-acetoxy-7-hydroxy-3,13(14)-clerodandien-18,19:15,16-diolide, ternatin, centipedic acid and 12-acetoxy-hawtriwaic lactone were isolated from the chemotype trans-pinocarveyl acetate. Analysis of the chemotype cisisopinocarveyl acetate yielded 12-acetoxy-7-hydroxy-3,13(14)-clerodandien-18,19:15,16-diolide, 12-epi-bacchotricuneatin, ternatin and scopoletin. Structural elucidation of the isolated compounds was established on the basis of spectral data through the use of 1D NMR and several 2D shift correlated NMR pulse sequences and comparison with literature data. Keywords: Egletes viscosa chemotypes, trans-pinocarveyl acetate, cis-isopinocarveyl acetate, infusion chemical constitution IntroductionEgletes viscosa Less (Asteraceae) is an annual herb mostly native to intertropical Americas that grows throughout the northeast of Brazil at the margins of river and lakes as soon as the raining season ends. It is popularly known as "macela" or "marcela", and sometimes as "macela-da-terra" to differentiate it from Achyrocline satureoides, other Asteraceae common at the south and southeast regions of Brazil. Due to its large household use for the preparation of a tea to which emmenagogue, diaphoretic, 1 stomachic and antidiarrhoea 2 properties seem to be related, dried flower buds of Egletes viscosa are widely sold in herbal stores and supermarkets of the Brazilian northeast.During the last decade, phytochemical, pharmacological and agronomic studies of Egletes viscosa have been performed in our research group. Previous works with the flower buds purchased from a herbal store in Fortaleza, Ceará, allowed to obtain an essential oil characterized by trans-pinocarveyl acetate 1 as the major constituent. 3 From the non-volatile fraction ternatin 2, and the diterpenes centipedic acid 3, barbatol 4, tarapacol 5, and 12-acetoxy-hawtriwaic lactone 6 were isolated. 3,4 The pharmacological studies showed anti-hepatotoxic, 5 antiperoxidative, 6 gastroprotective and antidiarrhoeal, 7 hepatoprotective, 8 antithrombotic, 9 anti-anaphylactic and anti-inflammatory 10,11 properties for ternatin 2; antinociceptive and gastroprotective for the diterpenes 3 and 6; 12 and antinociceptive, a...

A reatividade e estereosseletividade apresentadas por uma nova cepa de Candida tropicalis na redução de cetonas pró-quirais foram comparadas com cepas de microrganismos, estudadas em nosso laboratório, provenientes da biodiversidade brasileira. Neste caso, Candida tropicalis demonstrou-se como um agente redutor versátil e estereosseletivo na biorredução de uma série de cetonas aromáticas. Estes compostos pró-quirais foram convertidos aos correspondentes álcoois opticamente ativos com moderada a excelente estereopreferência dependendo da estrutura do substrato. Entre as cetonas utilizadas, as nitroacetofenonas foram enzimaticamente reduzidas aos correspondentes (S)-álcoois enantiopuros com completa conversão.The reactivity and stereoselectivity showed by a new strain of Candida tropicalis in the reduction of prochiral ketones have been compared with the ones previously attained in our laboratory using microorganisms from the Brazilian biodiversity. In this manner, Candida tropicalis has demonstrated its versatility as stereoselective agent in the bioreduction of a series of aromatic ketones. These prochiral compounds were converted into their corresponding optically alcohols with moderate to excellent stereopreference depending on the substrate structure. Among ketones tested, nitroacetophenones were enzymatically reduced to enantiopure (S)-alcohol with complete conversion. Keywords: alcohol dehydrogenases, biocatalysis, Candida tropicalis, ketones, yeast IntroductionChiral alcohols are an important class of organic substrates due to their properties as bioactive compounds and as starting materials for the synthesis of various biologically active materials.1 For example, enantiopure 1-phenylethanol is a chiral building block used in the fine chemical and pharmaceutical industries as an ophthalmic preservative, a solvatochromic dye, an inhibitor of cholesterol intestinal absorption and a mild floral fragrance. 2 In the synthesis of enantiopure chiral secondary alcohols, prochiral ketones are commonly used as starting materials using stereoselective chemical transformations or biocatalytic methods. Asymmetric reduction by chemical methods usually involves the use of expensive reagents or heavy metal catalysts.3 By contrast, biocatalysis applied to industrial processes has been shown as a very advantageous alternative to conventional chemical methods, and is widely used for the preparation of enantiomerically pure pharmaceuticals and other high added value compounds. 4 Enzymatic reduction of carbonyl groups represents one of the most important reactions employed in the synthesis of chiral alcohols. Enzymes that can be used for this transformation are oxidoreductases, which require the presence of a coenzyme, such as NADH or NADPH, which transfers the hydride anion to the carbonyl compound, being formed NAD + or NADP + . Whole cells of microorganisms can be also used in the enzymatic reduction of the carbonyl group. Each cell represents a small factory fully equipped for the reduction of the substrate bearing Candida...

The diterpene, 12-acetoxyhawtriwaic acid lactone (AHAL, tanabalin) isolated from the flower buds of Egletes viscosa Less. (Asteraceae) was evaluated on capsaicin-induced ear edema and hindpaw nociception in mice. AHAL (12.5, 25 and 50 mg/kg, P. O.) significantly attenuated the ear edema response to topically applied capsaicin (250 microg), in a dose-related manner. At similar doses, AHAL also suppressed the nocifensive paw-licking behavior induced by intraplantar injection of capsaicin (1.6 microg). These responses to capsaicin were also greatly inhibited by ruthenium red (3 mg/kg, S. C.), a non-competitive capsaicin receptor (TRPV1) antagonist. The anti-edema effect of AHAL (50 mg/kg) seems unrelated to either blockade of mast cell degranulation or to histamine and serotonin receptor antagonism since AHAL did not modify the paw edema response induced by intraplantar injections of compound 48/80, histamine or serotonin. However, the hindpaw edema induced by substance P and vascular permeability increase induced by intraperitoneal acetic acid were significantly suppressed by AHAL. The antinociceptive effect of AHAL (50 mg/kg) was unaffected by naloxone pretreatment but was significantly antagonized by theophylline and glibenclamide, the respective blockers of adenosine and K(ATP)-channels. AHAL (50 mg/kg, P. O.) did not impair the ambulation or motor coordination of mice in open-field and rota-rod tests. These data suggest that AHAL inhibits acute neurogenic inflammation possibly involving capsaicin-sensitive TRPV1-receptors, endogenous adenosine and ATP-sensitive potassium channels.

Effects of α-tocopherol and ternatin antioxidants on morphology and activation of goat preantral follicles in vitro cultured ABSTRACTThe effects of α-tocopherol and ternatin on the morphology, activation, and growth of goat preantral follicles in vitro cultured, for one or five days, were evaluated. Ovarian fragments were immediately fixed (non-cultured control) or in vitro cultured for one or five days in Minimum Essential Medium (MEM) with or without α-tocopherol or ternatin supplementation, both at concentrations of 5, 10, or 15µM, corresponding to the following treatments: MEM, TOC5, TOC10, TOC 15, TER5, TER10, and TER15. The percentages of morphologically normal preantral follicles in non-cultured ovarian tissue (control) was 73.2% and after five days of culture, there was a decrease on these percentages in all treatments (P<0.05) when compared with non-cultured control. Culture of ovarian cortex for five days increased the percentages of follicular activation in all treatments (P<0.05). Ultrastructural analysis did not confirm the integrity of caprine preantral follicles cultured for five days in medium containing antioxidants. This study demonstrated that α-tocopherol and ternatin can promote follicular activation; however, addition of these antioxidants in the tested concentrations reduced the follicular viability after in vitro culture.Keywords: caprine, preantral follicle, α-tocopherol, ternatin RESUMO

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