Antidiabetic effect of Euterpe oleracea Mart. (açaí) extract and exercise training on high-fat diet and streptozotocin-induced diabetic rats: A positive interaction.

A growing body of evidence suggests a protective role of polyphenols and exercise training on the disorders of type 2 diabetes mellitus (T2DM). We aimed to assess the effect of the açaí seed extract (ASE) associated with exercise training on diabetic complications induced by high-fat (HF) diet plus streptozotocin (STZ) in rats. Type 2 diabetes was induced by feeding rats with HF diet (55% fat) for 5 weeks and a single dose of STZ (35 mg/kg i.p.). Control (C) and Diabetic (D) animals were subdivided into four groups each: Sedentary, Training, ASE Sedentary, and ASE Training. ASE (200 mg/kg/day) was administered by gavage and the exercise training was performed on a treadmill (30min/day; 5 days/week) for 4 weeks after the diabetes induction. In type 2 diabetic rats, the treatment with ASE reduced blood glucose, insulin resistance, leptin and IL-6 levels, lipid profile, and vascular dysfunction. ASE increased the expression of insulin signaling proteins in skeletal muscle and adipose tissue and plasma GLP-1 levels. ASE associated with exercise training potentiated the reduction of glycemia by decreasing TNF-α levels, increasing pAKT and adiponectin expressions in adipose tissue, and IR and pAMPK expressions in skeletal muscle of type 2 diabetic rats. In conclusion, ASE treatment has an antidiabetic effect in type 2 diabetic rats by activating the insulin-signaling pathway in muscle and adipose tissue, increasing GLP-1 levels, and an anti-inflammatory action. Exercise training potentiates the glucose-lowering effect of ASE by activating adiponectin-AMPK pathway and increasing IR expression.

Salicytamide: a New Anti-inflammatory Designed Drug Candidate.

Salicytamide is a new drug developed through molecular modelling and rational drug design by the molecular association of paracetamol and salicylic acid. This study was conducted to assess the acute oral toxicity, antinociceptive, and antioedematogenic properties of salicytamide. Acute toxicity was based on the OECD 423 guidelines. Antinociceptive properties were investigated using the writhing, hot plate and formalin tests in Swiss mice. Antioedematogenic properties were evaluated using the carrageenan-induced paw oedema model and croton oil-induced dermatitis in Wistar rats. Salicytamide did not promote behavioural changes or animal deaths during acute oral toxicity evaluation. Furthermore, salicytamide exhibited peripheral antinociceptive activity as evidenced by the reduction in writhing behaviour (ED50 = 4.95 mg/kg) and licking time in the formalin test's inflammatory phase. Also, salicytamide elicited central antinociceptive activity on both hot plate test and formalin test's neurogenic phase. Additionally, salicytamide was effective in reducing carrageenan or croton oil-induced oedema formation. Overall, we have shown that salicytamide, proposed here as a new NSAID candidate, did not induce oral acute toxicity and elicited both peripheral antinociceptive effects (about 10-25 times more potent than its precursors in the writhing test) and antioedematogenic properties. Salicytamide also presented central antinociceptive activity, which seems to be mediated through opioid-independent mechanisms. These findings reveal salicytamide as a promising antinociceptive/antioedematogenic drug candidate.

Euterpe oleracea Mart. (açaí) seed extract associated with exercise training reduces hepatic steatosis in type 2 diabetic male rats.

Type 2 diabetes mellitus contributes to an increased risk of metabolic and morphological changes in key organs, such as the liver. We aimed to assess the effect of the açaí seed extract (ASE) associated with exercise training on hepatic steatosis induced by high-fat (HF) diet plus streptozotocin (STZ) in rats. Type 2 diabetes was induced by feeding rats with HF diet (55% fat) for 5 weeks, followed by a single low dose of STZ (35 mg/kg i.p.). Control and diabetic groups were subdivided into four groups that were fed with standard chow diet for 4 weeks. Control (C) group was subdivided into Sedentary C, Training C, ASE Sedentary C and ASE Training C. Diabetic (D) group was subdivided into Sedentary D, Training D, ASE Sedentary D and ASE Training D. ASE (200 mg/kg/day) was administered by intragastric gavage, and the exercise training was performed on a treadmill (30 min/day; 5 days/week). Treatment with ASE associated with exercise training reduced the blood glucose (70.2%), total cholesterol (81.2%), aspartate aminotransferase (51.7%) and hepatic triglyceride levels (66.8%) and steatosis (72%) in ASE Training D group compared with the Sedentary D group. ASE associated with exercise training reduced the hepatic lipogenic proteins' expression (77.3%) and increased the antioxidant defense (63.1%), pAMPK expression (70.2%), cholesterol transporters (71.1%) and the pLKB1/LKB1 ratio (57.1%) in type 2 diabetic rats. In conclusion, ASE treatment associated with exercise training protects against hepatic steatosis in diabetic rats by reducing hepatic lipogenesis and increasing antioxidant defense and cholesterol excretion.

Euterpe oleracea Mart.-Derived Polyphenols Protect Mice from Diet-Induced Obesity and Fatty Liver by Regulating Hepatic Lipogenesis and Cholesterol Excretion.

The aim of this study was to investigate the effect of a polyphenol-rich Açaí seed extract (ASE, 300 mg/kg-1d-1) on adiposity and hepatic steatosis in mice that were fed a high-fat (HF) diet and its underlying mechanisms based on hepatic lipid metabolism and oxidative stress. Four groups were studied: C57BL/6 mice that were fed with standard diet (10% fat, Control), 10% fat + ASE (ASE), 60% fat (HF), and 60% fat + ASE (HF + ASE) for 12 weeks. We evaluated the food intake, body weight gain, serum glucose and lipid profile, hepatic cholesterol and triacyglycerol (TG), hepatic expression of pAMPK, lipogenic proteins (SREBP-1c, pACC, ACC, HMG-CoA reductase) and cholesterol excretion transporters, ABCG5 and ABCG8. We also evaluated the steatosis in liver sections and oxidative stress. ASE reduced body weight gain, food intake, glucose levels, accumulation of cholesterol and TG in the liver, which was associated with a reduction of hepatic steatosis. The increased expressions of SREBP-1c and HMG-CoA reductase and reduced expressions of pAMPK and pACC/ACC in HF group were antagonized by ASE. The ABCG5 and ABCG8 transporters expressions were increased by the extract. The antioxidant effect of ASE was demonstrated in liver of HF mice by restoration of SOD, CAT and GPx activities and reduction of the increased levels of malondialdehyde and protein carbonylation. In conclusion, ASE substantially reduced the obesity and hepatic steatosis induced by HF diet by reducing lipogenesis, increasing cholesterol excretion and improving oxidative stress in the liver, providing a nutritional resource for prevention of obesity-related adiposity and hepatic steatosis.

Protective effect of Euterpe oleracea†Mart (açaí) extract on programmed changes in the adult rat offspring caused by maternal protein restriction during pregnancy.

OBJECTIVES: This study examined the effect of açaí (Euterpe oleracea Mart.) seed extract (ASE) on cardiovascular and renal alterations in adult offspring, whose mothers were fed a low-protein (LP) diet during pregnancy. METHODS: Four groups of rats were fed: control diet (20% protein); ASE (200 mg/kg per day); and LP (6% protein); LP + ASE (6% protein + ASE) during pregnancy. After weaning, all male offspring were fed a control diet and sacrificed at 4 months old. We evaluated the blood pressure, vascular function, serum and urinary parameters, plasma and kidney oxidative damage, and antioxidant activity and renal structural changes. KEY FINDINGS: Hypertension and the reduced acetylcholine-induced vasodilation in the LP group were prevented by ASE. Serum levels of urea, creatinine and fractional excretion of sodium were increased in LP and reduced in LP + ASE. ASE improved nitrite levels and the superoxide dismutase and glutathione peroxidase activity in LP, with a corresponding decrease of malondialdehyde and protein carbonyl levels. Kidney volume and glomeruli number were reduced and glomerular volume was increased in LP. These renal alterations were prevented by ASE. CONCLUSIONS: Treatment of protein-restricted dams with ASE provides protection from later-life hypertension, oxidative stress, renal functional and structural changes, probably through a vasodilator and antioxidant activity.

Antinociceptive, neurobehavioral and antioxidant effects of Eupatorium triplinerve Vahl on rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Eupatorium triplinerve Vahl belongs to the Asteraceae family, popularly known as Japana. It is a perennial shrub native to Amazon rainforests of South America. Its leaves are used through infusions, decoctions, baths, and tea. It is largely used in Brazilian folk medicine as sedative, febrifuge, stimulant, tonic and anti-inflammatory. AIM OF THE STUDY: The present study evaluated the putative effects of Eupatorium triplinerve on the central nervous system (CNS), including locomotor and anxiety activity, depression-like behavior, and antinociception and oxidative stress. MATERIALS AND METHODS: Two-month-old male Wistar rats (n=7-10 rats/group) and Swiss male and female mice of the species Mus musculus (n=7-10 per group) were administered with 100 mg/kg, 200 mg/kg, 400 mg/kg, 600 mg/kg, and 800 mg/kg of hydroalcoholic extracts of Eupatorium triplinerve (HEET). The behavioral assays included open-field (OF), elevated Plus-maze (EPM), and forced swimming tests (FS). The antinociceptive activity was verified using chemical (acetic acid and formalin) and thermal (hot plate) models of nociception. The oxidative stress levels were measured in rat blood samples after behavioral assays and Trolox equivalent antioxidant capacity (TEAC), nitric oxide and malondialdehyde (MDA) levels were measured in vivo. RESULTS: Oral pretreatment with HEET reduced the locomotion in OF test (200-800 mg/kg), increased central locomotion and open arms entries in the OF and EPM tests, respectively (600-800 mg/kg), and decreased the immobility time in the FS (200-800 mg/kg). It also reduced the writhing number evoked by acetic acid injection (200-800 mg/kg) and licking time in the first phase of the formalin test (400-800 mg/kg). In the oxidative stress assays, the extract decreased TEAC, Nitric Oxide and MDA levels in response to swimming stress induced in rats. CONCLUSIONS: These results were indicative for the first time that Eupatorium triplinerve exerted mild sedative, anxiolytic and antidepressive effects on the CNS. Antinociceptive effects not related to opioid system and antioxidant activity were also observed. These results support the ethnopharmacological use of Eupatorium triplinerve in popular medicine.

Vasorelaxant effects of 1-nitro-2-phenylethane, the main constituent of the essential oil of Aniba canelilla, in superior mesenteric arteries from spontaneously hypertensive rats.

The present study investigated the mechanisms underlying the vasorelaxant effects of the essential oil of Aniba canelilla (EOAC) and its main constituent 1-nitro-2-phenylethane (NP) in isolated superior mesenteric artery from spontaneously hypertensive rats (SHRs). At 0.1-1000 µg/mL, EOAC and NP relaxed SMA preparations pre-contracted with 75 mMKCl with IC(50) (geometric mean [95% confidence interval]) values of 294.19 [158.20-94.64] and 501.27 [378.60-624.00] µg/mL, respectively); or with phenylephrine (PHE) (IC(50)s=11.07 [6.40-15.68] and 7.91 [4.08-11.74) µg/mL, respectively). All these effects were reversible and remained unaltered by vascular endothelium removal. In preparations maintained under Ca(2+)-free conditions, EOAC and NP (both at 600 µg/mL) reduced the PHE-, but not the caffeine-induced contraction. In Ca(2+)-free and high K(+) (75 mM) medium, the contractions produced by CaCl(2) or BaCl(2) were reduced or even abolished by EOAC and NP at 100 and 600 µg/mL, respectively. EOAC and NP (both at 10-1000 µg/mL) also relaxed the contraction evoked by phorbol dibutyrate (IC(50)=52.66 [10.82-94.64] and 39.13 [31.55-46.72] µg/mL, respectively). It is concluded that NP has a myogenic endothelium-independent vasorelaxant effects and appears to be the active principle of the EOAC. Vasorelaxant effect induced by both EOAC and NP is preferential to receptor-activated pathways and it appears to occur intracellularly more than a superficial action restricted to the membrane environment such as a simple blocking activity on a given receptor or ion channel.

Euterpe oleracea Mart.-derived polyphenols prevent endothelial dysfunction and vascular structural changes in renovascular hypertensive rats: role of oxidative stress.

The consumption of polyphenol-rich foods is associated with a decreased risk of mortality from cardiovascular diseases. Previously, we have demonstrated that the stone of Euterpe oleracea Mart. (açaí) from the Amazon region exerts vasodilator and antioxidant actions. This study examined the effect of açaí stone extract (ASE) on the vascular functional and structural changes and oxidative stress associated with the two-kidney, one-clip (2K-1C) renovascular hypertension. 2K-1C and sham-operated rats were treated with ASE 200 mg/kg/day (or vehicle) for 40 days. Blood pressure was measured by tail plethysmography, and the vascular reactivity was evaluated in the rat isolated mesenteric arterial bed. Mesenteric protein expression of endothelial nitric oxide synthase (eNOS), superoxide dismutase 1 and 2 (SOD1 and SOD2), metalloproteinase 2 (MMP-2), and tissue inhibitor of MMPs (TIMP)-1 was assessed by Western blot; oxidative damage and antioxidant activity by spectrophotometry; MMP-2 levels by gelatin zymography; and structural changes by histological analysis. ASE prevented 2K-1C hypertension and the reduction of acetylcholine-induced vasodilation. The increased levels of malondialdehyde and carbonyl protein were reduced by ASE. SOD, catalase, and glutathione peroxidase activities and the expressions of SOD1 and SOD2, eNOS, and TIMP-1 were decreased in 2K-1C rats and recovered by ASE. In 2K-1C rats, ASE prevented vascular remodeling and the increased expression/levels of MMP-2. These findings indicate that ASE produces antihypertensive effect and prevents the endothelial dysfunction and vascular structural changes in 2K-1C hypertension, probably through mechanisms involving antioxidant effects, NOS activation, and inhibition of MMP-2 activation.

Antinociceptive and antispasmodic effects of the essential oil of Ocimum micranthum: potential anti-inflammatory properties.

The antinociceptive and antispasmodic properties of the essential oil of OCIMUM micranthum (EOOM) were characterized. In mice, EOOM (15-100 mg · kg (-1), p. o.) reduced both the writhing responses induced by acetic acid and the licking-time induced by formalin, being inert on the hot plate test. In rat trachea, EOOM relaxed sustained contractions induced by KCl or carbachol (CCh). Its constituents, ( E)- [( E)-MC] and ( Z)-methyl cinnamate [( Z)-MC], reproduced several effects of EOOM. Inhaled as aerosol, EOOM prevented tracheal hyperresponsiveness to KCl or CCh in ovalbumin-sensitized animals after antigen challenge. Thus, EOOM exerts peripheral analgesia in nociception of inflammatory origin and has antispasmodic actions on rat airways under an inflammatory environment. Its effects are mainly due to ( E)-MC, which makes this substance potentially interesting for studies involving conjunctly smooth muscle cells, nociception, and inflammation. Other EOOM constituents also appear to be involved in its pharmacological actions.

Antioxidant capacity and larvicidal activity of essential oil and extracts from Lippia grandis

The leaves and thin branches of Lippia grandis Schauer, Verbenaceae, are used for flavoring of food in the Brazilian Amazon, as substitute for oregano. In this study the constituents of the essential oil were identified and the antioxidant capacity and larvicidal activity of the oil and methanol extract and its sub-fractions were evaluated. A sensory evaluation was determined in view of absence of toxicity. The oil showed a yield of 2.1 percent and its main constituents were thymol (45.8 percent), p-cymene (14.3 percent), γ-terpinene (10.5 percent), carvacrol (9.9 percent) and thymol methyl ether (4.8 percent), totalizing 85 percent. The DPPH radical scavenging activity showed values for the EC50 between 9.0 and 130.5 µg mL-1 and the TEAC/ABTS values varied from 131.1 to 336.0 mg TE/g, indicating significant antioxidant activity for the plant. The total phenolic content ranged from 223.0 to 761.4 mg GAE/g, contributing to the antioxidant activity observed. The crude extracts inhibited the bleaching of β-carotene and the oil showed the greatest inhibition (42.5 percent). The oil (LgO, 7.6±2.4 µg mL-1) showed strong larvicidal activity against the brine shrimp bioassay. The sensory evaluation was highly satisfactory in comparison to oregano. The results are very promising for the use of L. grandis in seasoning and antioxidant products.

Addition of açaí (Euterpe oleracea) to cigarettes has a protective effect against emphysema in mice.

Chronic inhalation of cigarette smoke (CS) induces emphysema by the damage contributed by oxidative stress during inhalation of CS. Ingestion of açai fruits (Euterpe oleracea) in animals has both antioxidant and anti-inflammatory effects. This study compared lung damage in mice induced by chronic (60-day) inhalation of regular CS and smoke from cigarettes containing 100mg of hydroalcoholic extract of açai berry stone (CS + A). Sham smoke-exposed mice served as the control group. Mice were sacrificed on day 60, bronchoalveolar lavage was performed, and the lungs were removed for histological and biochemical analyses. Histopathological investigation showed enlargement of alveolar space in CS mice compared to CS + A and control mice. The increase in leukocytes in the CS group was higher than the increase observed in the CS + A group. Oxidative stress, as evaluated by antioxidant enzyme activities, mieloperoxidase, glutathione, and 4-hydroxynonenal, was reduced in mice exposed to CS+A versus CS. Macrophage and neutrophil elastase levels were reduced in mice exposed to CS + A versus CS. Thus, the presence of açai extract in cigarettes had a protective effect against emphysema in mice, probably by reducing oxidative and inflammatory reactions. These results raise the possibility that addition of açaí extract to normal cigarettes could reduce their harmful effects.

Cardiovascular effects of 1-nitro-2-phenylethane, the main constituent of the essential oil of Aniba canelilla, in spontaneously hypertensive rats.

This study investigated the cardiovascular responses to the essential oil of Aniba canelilla (EOAC) and its main constituent 1-nitro-2-phenylethane (NP) in spontaneously hypertensive rats (SHRs). In anesthetized SHRs, intravenous (i.v.) bolus injections of EOAC (1-20 mg/kg) or NP (1-10 mg/kg) elicited dose-dependent hypotensive and bradycardiac effects, which were characterized in two periods (phases 1 and 2). The first rapid component (phase 1) evoked by EOAC and NP both at 10 mg/kg was absent after left ventricle injection, fully abolished by bilateral vagotomy and perineural treatment of both cervical vagus nerves with capsaicin (250 µg/mL) while remained unaltered by i.v. pretreatment with capsazepine (1 mg/kg) or ondansetron (30 µg/kg). In conscious SHRs, NP (5 and 10 mg/kg, i.v.) evoked rapid hypotensive and bradycardiac effects (phase 1) that were fully abolished by methylatropine (1 mg/kg, i.v.) pretreatment. In rat endothelium-containing mesenteric preparations, increasing concentrations (0.1-1000 µg/mL) of EOAC and NP relaxed the phenylephrine-induced contraction in a concentration-dependent manner. It is concluded that NP induces a vago-vagal bradycardiac and depressor reflex (phase 1) that apparently results from the stimulation of vagal pulmonary rather than cardiac C-fiber afferents. This effect does not appear to involve activation of either vanilloid TPRV(1) or 5-HT(3) receptors located on vagal sensory nerves. The phase 2 hypotensive response to i.v. NP seems to result, at least in part, from its direct vasodilatory effect on the peripheral smooth muscle. All in vivo and in vitro effects of EOAC are mostly attributed to the actions of its main constituent NP.

Effects of an extract obtained from fruits of Euterpe oleracea Mart. in the components of metabolic syndrome induced in C57BL/6J mice fed a high-fat diet.

Previously, we have demonstrated that the seed of Euterpe oleracea Mart. (açaí) from the Amazon region exerts vasodilator and antihypertensive actions. The aim of our study was to assess the effects of oral chronic treatment with açaí seed extract (ASE, 300 mg · kg(-1) · d(-1)) on high-fat (HF) diet­induced metabolic syndrome (MS) in C57BL/6J mice. Four groups of C57BL/6 mice were fed with control diet (10% fat), ASE (10% fat), HF (60% fat), and HF + ASE (60% fat plus ASE) for 12 weeks. The vasodilator effects of acetylcholine (ACh) and nitroglycerine (NG) were studied in perfused mesenteric arterial bed. Body weight, plasma total cholesterol, triglyceride, glucose and insulin levels, oral glucose tolerance test, and oxidative damage were determined, and the insulin resistance measured by Homeostatic Model Assessment (HOMA) index. Vasodilator response to ACh but not to NG was reduced in HF mice, and ASE restored the response. Increased plasma malondialdehyde levels, body weight, plasma triglyceride, total cholesterol, glucose levels, and insulin resistance were observed in HF mice and reduced by ASE. Treatment with ASE also reduced glucose intolerance observed by oral glucose tolerance test in HF mice. In conclusion, ASE protected C57BL/6J mice fed HF diet from phenotypic and metabolic characteristics of MS, providing an alternative nutritional resource for prevention of MS.

1-Nitro-2-phenylethane, the main constituent of the essential oil of Aniba canelilla, elicits a vago-vagal bradycardiac and depressor reflex in normotensive rats.

Previously, it was shown that intravenous (i.v.) treatment with the essential oil of Aniba canelilla (EOAC) elicited a hypotensive response that is due to active vascular relaxation rather than to the withdrawal of sympathetic tone. The present study investigated mechanisms underlying the cardiovascular responses to 1-nitro-2-phenylethane, the main constituent of the EOAC. In pentobarbital-anesthetized normotensive rats, 1-nitro-2-phenylethane (1-10mg/kg, i.v.) elicited dose-dependent hypotensive and bradycardiac effects which were characterized in two periods (phases 1 and 2). The first rapid component (phase 1) evoked by 1-nitro-2-phenylethane (10mg/kg) was fully abolished by bilateral vagotomy, perineural treatment of both cervical vagus nerves with capsaicin (250 microg/ml) and was absent after left ventricle injection. However, pretreatment with capsazepine (1mg/kg, i.v.) or ondansetron (30 microg/kg, i.v.) did not alter phase 1 of the cardiovascular responses to 1-nitro-2-phenylethane (10mg/kg, i.v.). In conscious rats, 1-nitro-2-phenylethane (1-10mg/kg, i.v.) evoked rapid hypotensive and bradycardiac (phase 1) effects that were fully abolished by methylatropine (1mg/kg, i.v.). It is concluded that 1-nitro-2-phenylethane induces a vago-vagal bradycardiac and depressor reflex (phase 1) that apparently results from the stimulation of vagal pulmonary rather than cardiac C-fiber afferents. The transduction mechanism of the 1-nitro-2-phenylethane excitation of C-fiber endings is not fully understood and does not appear to involve activation of either Vanilloid TPRV(1) or 5-HT(3) receptors. The phase 2 hypotensive response to 1-nitro-2-phenylethane seems to result, at least in part, from a direct vasodilatory effect since 1-nitro-2-phenylethane (1-300 microg/ml) induced a concentration-dependent reduction of phenylephrine-induced contraction in rat endothelium-containing aorta preparations.

Essential oil composition and antioxidant capacity of Lippia schomburgkiana.

The leaves and fine stems of Lippia schomburgkiana recorded an essential yield of 1.8%, the main constituents of which were 1,8-cineole (64.1%) and alpha-terpineol (12.0%). The methanol extract of L. schomburgkiana inhibited the DPPH radical, resulting in an EC50 value of 16.1 +/- 0.7 microg x mL(-1), which is only three times lower than that of trolox (4.7 +/- 0.4 microg x mL(-1)), signifying a high antioxidant activity for the species. The amount of total phenolics (376.7 +/- 35.5 mg GAE/g) and the trolox equivalent antioxidant capacity (327.0 +/- 24.8 mg TE/g) of the methanol extract confirmed the significant antioxidative capacity of this plant. The brine shrimp bioassay carried out on the oil (49.6 +/- 0.4 microg x mL(-1)) showed high toxicity, providing important evidence of its biological activity. The sensory evaluation of the leaves of L. schomburgkiana showed a percentage acceptance value very close to commercial oregano, indicating that the plant can be used in spice and condiment products.

Essential oil composition of three Peperomia species from the Amazon, Brazil.

The essential oils of three species of Peperomia from the Amazon, Brazil, were hydrodistilled and their 96 volatile constituents identified by GC and GC-MS. The main constituents found in the oil of P. macrostachya were epi-alpha-bisabolol (15.9%), caryophyllene oxide (12.9%), myristicin (7.6%), an aromatic compound (6.6%) and limonene (5.4%). The oil of P. pellucida was dominated by dillapiole (55.3%), (E)-caryophyllene (14.3%) and carotol (8.1%). The major volatile found in the oil of P. rotundifolia was decanal (43.3%), probably a fatty acid-derived compound, followed by dihydro-P3-santalol (9.0%), (E)-nerolidol (7.9%) and limonene (7.7%). The aromatic compounds elemicin, myristicin, apiole, dillapiole and safrole identified in these Peperomia species has been found also in Amazon Piper species. The oils and methanol extracts showed high brine shrimp larvicidal activities. The oil of P. rotundifolia (LC50 = 1.9 +/- 0.1 microg/mL) was the more toxic, followed by the extract of P. pellucida (LC50 = 2.4 +/- 0.5 microg/mL) and the oil of P. macrostachya (LC50 = 9.0 +/- 0.4 microg/mL), therefore with important biological properties.

Antinociceptive activity of 1-nitro-2-phenylethane, the main component of Aniba canelilla essential oil.

Aniba canelilla (H.B.K.) Mez is a medicinal plant used in the Amazon folk therapeutic as antispasmodic, antidiarreic, carminative, tonic agent and a stimulant of the digestive and central nervous system. Our preliminary studies showed that the plant essential oil has analgesic activity in mice. Now, we are reporting the antinociceptive effect of the compound 1-nitro-2-phenylethane (97.5%), the main component of the essential oil of Aniba canelilla, which was obtained by column chromatographic purification. In the writhing test this compound was dosed at 15, 25 and 50 mg/kg reducing the abdominal writhes in a significant manner; in the hot plate test it was assayed at 50, 100 and 200 mg/kg producing no alterations in the latency time when compared to the control; and in the formalin test the 1-nitro-2-phenylethane was tested at 50 and 25 mg/kg decreasing significantly the second phase of the algic stimulus. The study suggests that the 1-nitro-2-phenylethane has analgesic activity, probably of peripheral origin. The mechanism involved is not completely understood, however, the results suggest that the opioid receptors are involved in the antinociceptive action observed to 1-nitro-phenylethane.

Cafeína em suplementos energéticos consumidos em Belém, Pará / Caffeine in energy supplements consumed in Belem, Para

Determinar os teores deste alcalóide em suplementos energéticos comercializados nacidade de Belém,Pará. Método: realizou-se um estudo de pesquisa analítico por cromatografialíquida de alta eficiência com detecção no ultravioleta. Resultados: a concentração média decafeína nas amostras analisadas foi 19.2±18.8mg/10mL, com intervalo de 2.45 a 62.4mg/10mLe coeficiente de variação de 98%. Conclusão: os resultados deste estudo demonstraram que osteores de cafeína nos suplementos energéticos não representa riscos a saúde do consumidor,por outro lado indicaram a necessidade da intensificação das medidas regulatórias referentes arotulagem inadequada, composição e controle de qualidade dos componentes

to determine the caffeine contents of 30 samples of energy supplements from Belem, PA, to evaluate the safety of the human consumption. Method: Analysis of caffeine in energy supplements by high performance liquid chromatography with ultraviolet detection. Results:The mean concentration of caffeine in energy supplements was 19.2±18.8mg/10ml ranging from2.45 to 6.24mg/10mL. The variation coefficient was 98%. Conclusion: contents of energy supplements don?t represent a risk for human health, but regulatory approaches for the evaluation of composition and quality control are needs.

Variability in essential-oil composition of Piper marginatum sensu lato.

This paper contains data on the chemical composition of the essential oils of 22 leaf samples of Piper marginatum Jacq. collected in different areas and ecosystems of the brazilian Amazon, as well as an overview of the available literature. The species presents a large synonymy based on their different leaf characteristics and distinct scents where some of them smell like anise or very close compounds. By GC, GC/MS, and cluster analysis, we identified seven chemotypes for the leaf oils. The main components found in chemotype I were safrole (1) and 3,4-(methylenedioxy)propiophenone (2). The chemotype II was dominated by 3,4-(methylenedioxy)propiophenone (2) and p-mentha-1(7),8-diene (10). The major compounds identified in chemotype III were 3,4-(methylenedioxy)propiophenone (2), myristicin (3), (E)-beta-ocimene (11), and gamma-terpinene (12). In the chemotype IV, the principal constituents were beta-caryophyllene (13), alpha-copaene (14), and 3,4-(methylenedioxy)propiophenone (2). The chemotype V was dominated by (E)-isoosmorhizole (6), (E)-anethole (8), and isoosmorhizole (7). The main compounds found in the chemotype VI were 2-methoxy-4,5-(methylenedioxy)propiophenone (4), methoxy-4,5-(methylenedioxy)propiophenone isomer 5, and (E)-isoosmorhizole (6). The major constituents in chemotype VII were beta-caryophyllene (13), bicyclogermacrene (15), and (E)-asarone (9).

Antioxidant capacity and cytotoxicity of essential oil and methanol extract of Aniba canelilla (H.B.K.) Mez.

The leaves and fine stems, bark, and trunk wood oils of Aniba canelilla showed yields ranging from 0.2 to 1.3%. The main volatile constituent identified in the oils was 1-nitro -2-phenylethane (70.2-92.1%), as expected. The mean of DPPH radical scavenging activity (EC 50) of the oils (198.17 +/- 1.95 microg mL(-1)) was low in comparison with that of wood methanol extracts (4.41 +/- 0.12 microg mL(-1)), the value of which was equivalent to that of Trolox (4.67 +/- 0.35 microg mL(-1)), used as antioxidant standard. The mean amount of total phenolics (TP) (710.53 +/- 23.16 mg of GAE/g) and this value calculated as Trolox equivalent antioxidant capacity (TEAC) (899.50 +/- 6.50 mg of TE/g) of the wood methanol extracts confirmed the high antioxidant activity of the species. On the other hand, in the brine shrimp bioassay the values of lethal concentration (LC50) for the oils (21.61 +/- 1.21 microg mL(-1)) and 1-nitro-2-phenylethane (20.37 +/- 0.99 microg mL(-1)) were lower than that of the wood methanol extracts (91.38 +/- 7.20 microg mL(-1)), showing significant biological activities.