Quality of propolis commercialized in the informal market

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação farmacognóstica da própolis da região de Maringá

Os autores propõem procedimentos para estabelecer o controle de qualidade da própolis. Para tanto, foram adaptadas e executadas técnicas farmacopéicas e/ou desenvolvidas técnicas novas. Foram estabelecidos perfis dos teores de flavonóides, de ceras, de substâncias voláteis totais (através da perda por dessecação) e de cinzas totais. Os valores obtidos para as amostras de própolis estudadas, coletadas em um apiário-escola, foram comparados com os de própolis adquiridas no mercado. Foi estabelecido, ainda, o perfil destes parâmetros para amostras de própolis coletadas nos diferentes locais da colméla, no periodo de três anos, com coletas de inverno e verão. Os teores de flavonóides variaram entre 2,05 - 5,52%.

Controle da qualidade do fruto de Syzygium cumini (L.) Skeels

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Toxicity of Dimorphandra mollis to Workers of Apis mellifera

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Isolation and HPLC quantitative analysis of flavonoid glycosides from Brazilian beverages (Maytenus ilicifolia and M-aquifolium)

Aqueous infusions of Brazilian Maytenus leaves are used as beverages, foodstuffs, and phytomedicines. Previously, we isolated two new flavonoid tetrasaccharides from the infusion of Maytenus aquifolium leaves that showed antiulcer activity. In this investigation a new flavonoid tetrasaccharide, kaempferol-3-O-alpha -L-rhamnopyranosyl (1-6)-O-[alpha -L-arabinopyranosyl (1 -->3)-O-alpha -L-rhamnopyranosyl (1-2)]-O-beta -D-galactopyranoside (3), was isolated, together with kaempferol tri- and disaccharides and quercetin trisaccharides from the aqueous infusion of Maytenus ilicifolia leaves. All structures were elucidated by ES-MS and NMR spectroscopic methods. The quantitative analysis of the flavonoid glycosides from Maytenus ilicifolia and M. aquifolium has been performed by HPLC.

Gastric antiulcer activity of Syngonanthus arthrotrichus SILVEIRA

Syngonanthus arthrotrichus SILVEIRA, popularly known as sempre-vivas mini-saia, is found in mountains of the Espinhaco range in the Brazilian states of Bahia and Minas Gerais. Extracts of this species contain several constituents, including flavonoids which may have antiulcerogenic activity. An ethanolic extract (EEOH), and flavonoid-rich (FRF) and flavonoid-deficient (FDF) fractions obtained from the scapes of S. arthrotrichus were investigated for their ability to prevent ulceration of the gastric mucosa in mice and rats. In the ethanol/HCl-induced ulcer model, lansoprazole (30 mg/kg), EEOH (50, 100, 250 mg/kg) given orally protected the gastric mucosal against injury in mice by 79%, 78%, 73%, and 64% respectively. In the ethanol-induced gastric ulcer model in rats, the lansoprazole (30 mg/kg), FRF and FDF (100 mg/kg) significantly protected the gastric mucosal of rats by 65%, 38% and 25% respectively when compared with the negative control group. In indomethacin/ bethanechol-induced gastric ulcers, cimetidine (100 mg/kg) and the EEOH (100, 250 mg/kg) inhibited gastric ulcer formation by 73%, 55% and 32% respectively. In this exactly model other treatments as cimetidine, FRF and FDF (100 mg/kg) each caused 54%, 36% and 45% inhibition, respectively. In the stress-induced gastric ulcer model, cimetidine (100 mg/kg) and the EEOH (50, 100, 250 mg/kg), inhibited gastric ulcer formation by 63%, 73%, 68% and 69% respectively. In the same model, cimetidine, FRF and FDF (100 mg/kg) significantly protected the gastric mucosal of the mice by 60%, 51% and 47% when compared to the control group. In pylorus-ligated mice, cimetidine (positive control) and FRF significantly decreased gastric acid secretion, increased gastric pH and reduced the acid output when compared to the negative control. FDF had no significant effect on these parameters. The protection provided by FRF probably involved an antisecretory mechanism mediated by flavonoids which were absent in FDF. The amount of adherent mucous in the stomach contents was also evaluated with the treatments carbenoxolone (200 mg/kg), FRF and FDF (100 mg/kg) treatment. Each treatments significantly increased the amount of adherent mucous in the gastric juice (8.67 +/- 1.73, 3.35 +/- 1.59, 2.1 +/- 0.41 mg/g of wet tissue, respectively) compared to the control group, indicating a cytoprotective action on the gastric mucosa. Treatment with FRF plus indomethacin and FDF plus indomethacin reduced the prostaglandin biosyntesis (13.6 +/- 6.5, 27 +/- 5.5 pg/well) by the mucosa, indicating that the cytoprotective action on the gastric mucosa was not related to the level of prostaglandins. Only FDF (38 +/- 17 pg/well) maintained the level of prostaglandins and guaranteed the integrity of the mucosa. The results indicate that the EEOH, FRF and FDF have antisecretory and cytoprotective actions, that may be related to the presence of luteoline in the extract and active fractions.

Chalcone-flavone tetramer and biflavones from Aristolochia ridicula

Biflavones and a chalcone flavone tetramer were isolated from the leaves of Aristolochia ridicula, together with proto-quercitol. Their structures were determined by spectroscopic methods. (c) 2005 Elsevier Ltd. All rights reserved.

Chemical profile of Eriocaulon ligulatum (Vell.) LB Smith (Eriocaulaceae)

Two new and six known flavonoids and two known naphthopyranones have been isolated by chromatographic methods and spectrometrically identified in capitulae and scapes of Eriocaulon ligulatum (Vell.) L.B. Smith (Eriocaulaceac). The presence of naphthopyranones suggests approximation between Eriocaulon and Paepalanthus genus. (c) 2005 Elsevier Ltd. All rights reserved.

Effects of tea from Turnera ulmifolia L. on mouse gastric mucosa support the Turneraceae as a new source of antiulcerogenic drugs

Turnera ulmifolia is a plant belonging to the family Turneraceae, popularly known in Brazil as chanana. This species is distributed from Guyana to southern Brazil where it is considered a weed. The plant occurs in tropical rain forest, fields, and gardens. Chanana tea is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric dysfunction including gastric and duodenal ulcers. In this study, the ability of a lyophilized infusion, as an aqueous fraction (AqF) of the aerial parts of T. ulmifolia, was investigated for its ability to prevent ulceration of the gastric and duodenal mucosa was examined in mice and rats, respectively. The AqF significantly reduced the formation of lesions associated with HCl/ethanol administration by 39% and 46%, respectively, at doses of 500 mg/kg and 1000 mg/kg, p.o. The AqF also significantly reduced the incidence of gastric lesions induced by a combination of indomethacin and bethanechol by 58% and 72% at doses of 500 mg/kg and 1000 mg/kg, respectively. In stress-induced gastric ulcer, the inhibition by the AqF was 48%, 57%, and 58% at doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg, respectively (p<0.05). A pyloric ligature experiment showed that the highest dose of the AqF significantly affected the gastric juice parameters by increasing the pH from 2.5 (control) to 5.3 and decreasing the acid output from 11.3 (control) to 3.7 mEq/ml/4 h. The AqF had no significant effect on duodenal ulcers induced by cysteamine. Preliminary phytochemical screening confirmed that flavonoids were the major constituents of the AqF of T. ulmifolia. These results indicate that this extract has a significant antiulcerogenic effect, as popularly believed.

Inhibition of hydrogen peroxide, nitric oxide and TNF-alpha production in peritoneal macrophages by ethyl acetate fraction from Alchornea glandulosa

The effects of Alchornea glandulosa ethyl acetate fraction (AGF) on hydrogen peroxide (H2O2), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production in peritoneal macrophages activated with lipopolysaccharide (LPS) or phorbol myristate acetate (PMA) were investigated. Analysis by thin layer chromatography (TLC) of AGF showed several constituents, including flavonoids, which may have anti-inflammatory activity. Inhibitory effects of the fraction in H2O2 and NO production ranged from 8.59 +/- 7.84% to 70.56 +/- 4.16% and from 16.06 +/- 3.65% to 38.73 +/- 3.90%, respectively. The TNF-alpha production was only partially inhibited in the tested concentrations (12.21 +/- 6.23%-15.16 +/- 0.96%). According to these results, it is suggested that AGF has anti-inflammatory activity. This medicinal plant may have therapeutic potential in the control of inflammatory disorders.

Effect of Mouriri pusa extracts on experimentally induced gastric lesions in rodents: Role of endogenous sulfhydryls compounds and nitric oxide in gastroprotection

Several plants are used in folk medicine to treat gastrointestinal disorders. Mouriri pusa Gardn. (Melastomataceae) is a medicinal plant commonly used in the central region of Brazil against gastric ulcer. Two organic extracts methanolic (MeOH) and dichloromethane (DCM) obtained by sequential extraction from the leaves of Mouriri pusa were evaluated for their ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% EtOH, absolute ethanol, non-steroidal anti-inflammatory drug, stress and pylorus ligature) in mice and rats. The best results were obtained after pretreatment with MeOH extract whereas the DCM extract did not show the same significant antiulcerogenic activity. No acute toxicity was observed in animals treated with 5 g/kg, p.o. of MeOH extract. The mechanism involving the antiulcerogenic action of MeOH extract seemed to be related to NO generation and also suggested the effective participation of endogenous sulfhydryl group in the gastroprotective action. Phytochemical investigation of the MeOH extract of Mouriri pusa yielded tannins, flavonoids and (-)-epicatechin. The presence of these phenolic compounds probably would explain the antiulcerogenic effect of the polar extract of Mouriri pusa leaves. (c) 2006 Elsevier B.V.. All rights reserved.

Flavonoid increase in soybean as a response to Nezara viridula injury and its effect on insect-feeding preference

The ability of the stink bug (Nezara viridula) to induce and/or increase production of chemical defenses, i.e., flavonoids, in immature seeds of five genotypes of soybean (BR-16, IAC-100, PI 227687, PI 229358, and PI 274454) was investigated under greenhouse and laboratory conditions. Samples from pods of each genotype damaged by stink bug were analyzed for flavonoid content with high performance liquid chromatography. A dual-choice test was conducted to evaluate the feeding preference of N. viridula comparing BR-16 pods treated with extracts of PI 227687 seeds (with and without stink-bug injury), with water-treated pods. Seeds of PI 227687 damaged by N. viridula presented the highest concentration (352 mug/g) of daidzin (4'-hydroxyisoflavone-7-glucoside). The same trend was observed with genistin (4',5,7-trihydroxyisoflavone-7-glucoside): PI 227687 contained 142.4 mug/g, PI 274454, 31.6 mug/g, and PI 229358, 38.9 mug/g. Seeds damaged by stink bugs had higher isoflavone contents (daidzin and genistin), compared to controls. However, after being damaged, PI 274454 and PI 229358 produced less genistin than the other genotypes and no differences in concentration between damaged and nondamaged plants of this genotypes were observed. The numbers of observations of the insect feeding and the numbers of stylet sheaths left in water-treated BR-16 pods were greater than in those treated with PI 227687 extracts. The insects fed for longer periods on BR-16 pods treated with extract of PI 227687 without injury compared to those that were treated with extract of PI 227687 previously injured by stink bugs. Extracts of PI 227687 pods ( damaged or not) were deterrent to adults of N. viridula, and insect injury increased concentrations of daidzin and genistin in PI 227687 seeds. The deterrence seemed to be more pronounced after pods had suffered stink-bug injury.

Antioxidant flavan-3-ols and flavonol glycosides from Maytenus aquifolium

TLC autographic assay revealed, in the EtOAc extract obtained from leaves and root bark of Maytenus aquifolium (Celastraceae), the presence of five compounds exhibiting antioxidant properties towards beta-carotene. They were isolated and identified as epigallocatechin (1), (+) ouratea-catechin (2), proanthocyanidin (3), kaempferol 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl (4) and quercetin 3-O-alpha-L-rhamnopyranosyl (1-->6)-O-beta-D-glucopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranosyl (5). The isolates were investigated for their redox properties using cyclic voltammetry and for their radical scavenging abilities through spectrophotometric assay on the reduction of 2,2-diphenyl-pycryl hydrazyl (DPPH). These results were correlated to the inhibition of beta-carotene bleaching on TLC autographic assay and to structural features of the flavonoids. Copyright (C) 2003 John Wiley Sons, Ltd.

Intestinal antiinflammatory activity of a lyophilized infusion of Turnera ulmifolia in TNBS rat colitis

Turnera ulmifolia is a plant popularly known in Brazil and South America as chanana. Some species of Turnera are widely used in folk medicine for different types of inflammatory diseases. In this study, the preventive intestinal antiinflammatory activity of a lyophilized infusion obtained from the aerial parts of T. ulmifolia was tested in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. The results obtained revealed that pretreatment to colitic rats with the extract, at 250 and 500 mg/kg, significantly attenuated the colonic damage induced by TNBS. This beneficial effect was associated with an improvement in the colonic oxidative status, since the infusion prevented the glutathione depletion that occurred as a consequence of the colonic inflammation. on the other hand, this antioxidant activity was confirmed in in vitro studies. In conclusion, the preventive effect exerted by the lyophilized infusion of T. ulmifolia in the TNBS model of rat colitis is probably related to its antioxidant properties, due to its flavonoids content. (c) 2006 Elsevier B.V. All rights reserved.

Antifungal constituents from roots of Virola surinamensis

Chromatographic fractionation of the dichloromethane extract from roots of Virola surinamensis yielded two new natural products, 3-epi-juruenolide C and 2'-hydroxy-7,4'-dimethoxyisoflavone, as well as various known steroids, lignans, isoflavones, flavonoids and diarylpropanes. of these, alpha,2'-dihydroxy-4,3'-dimethoxydihydrochal biochanin A and 2'-hydroxy-7,4'-dimethoxyisoflavone displayed antifungal activity against Cladosporium cladosporioides at a minimum amount of 5 mu g, whereas 7-hydroxyflavanone and 7-hydroxy-4'-methoxyisoflavone exhibited an antifungal activity 10-fold higher than the positive control Nystatin. (C) 1999 Elsevier B.V. Ltd. All rights reserved.