8 resultados para Citrus flavonoids

em Universidade Federal do Rio Grande do Norte(UFRN)


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The decoction of Brazilian pepper tree barks (Schinus terebinthifolius, Raddi), is used in medicine as wound healing and antiinflamatory. Once extracts from this plant are used for acceleration of scar s process, it is important to study their mutagenic and genotoxic potential. In previous works in our laboratory, it was observed mutagenicity caused by the decoction when in high concentrations. Among the chemical compounds of this plant that could be able to induce mutation, the flavonoids were the only group that was referred to have either an oxidant or antioxidant potential. The flavonoids were isolated, purified and quantified by adsorptive column chromatography under silica gel, bacterial and in vitro genotoxic tests were realized to determine if the flavonoids were the responsible agents for this mutagenicity found. The tests realized with plasmidial DNA were indicative that the flavonoids are probably genotoxic, due to the presence of correlation between increase of the flavonoid concentration and in plasmidial DNA double strand breakage visualized in agarose gel, as well as they were capable to generated abasic sites shown by the in vitro treatment with exonuclease III. The same tests with plasmidial DNA in the presence of copper [10 µM] and of a Tris-HCl pH 7.5 [10 µM] buffer were realized with the isolated flavonoids to determine if there would be or not participation of reactive oxygen species (ROS). The transformation of plasmidial DNA in different bacterial strains proficient and deficient in DNA repair enzymes in the presence or not of a Tris-HCl buffer, suggests that the enzymes that repair oxidative lesions are necessary to repair the lesions generated by the flavonoids and that ROS are generated and are necessary to promote the lesions. Bacterial tests with Escherichia coli strains of the CC collection (deficient or not for DNA repair enzymes), showed that the flavonoids are able to increase the frequency of mutations, mainly in strains mutated in repair enzymes (MutM, MutY-glicosylases and double mutant), suggesting that these agents are responsible for the enhancement in the mutation rate. In order to determine the mutation spectrum caused by the flavonoids of the Brazilian pepper tree stem bark, plasmidial DNA previously treated with the flavonoids were transformed in bacterial strains deficient and proficient in the DNA repair enzymes, followed by a blue-white selection with X-gal, DNA amplification by PCR and sequencing the positive mutant clones. Analysis of the mutants obtained from strains CC104, CC104mutM, CC104mutY, CC104mutMmutY, BW9101, BW9109 indicated a predominance of some mutations like G:C to C:G that can be correlated with the origin of 8-oxoG, due to oxidative lesions caused by the flavonoids. So it can concluded that the flavonoid isolated or in fractions enriched on them are genotoxic and mutagenic, and their mutations are predominantly oxidative, mediated by ROS, and the lesions are recognized by the BER system. In this way it is proposed that the flavonoids can act in two different ways to generate the DNA lesion: 1. in a Fenton-like reaction, when the flavonoid are in the presence of metal ions and that together with the water generate ROS that promotes the DNA lesions; 2. in another way the lesions can be generated by the formation of ROS due to the internal chemical structure of the flavonoid molecule due to the quantity and location of hydroxyl groups, and so producing the DNA lesions, those lesions can be directly (suggested by the in vitro experiments) or indirectly done (supported by the experiments using the CC bacterial strains)

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The main aim of this study was to compare the procedure for dehydration of Gracilaria birdiae prepared handmade and laboratory, collected in the northern coast of Rio Grande do Norte. The sample was collected in the Rio do Fogo beach in march 2009. The sample collected followed by two processing, the first the material prepared in laboratory was air-dried at 50°C for 24 hours in air-flow oven. The second the handmade sample was air-dried on the sun during three days. The extract was prepared in three different solvents: ethanol, hydroethanol and water, resulting in ethanol, hidroethanol and aqueous extracts from handmade and laboratory sample. In according with results only the ethanol extract was fractionated yielding the fractions hexane, dichloromethane and ethyl acetate fractions. The different process to obtain Gracilaria birdiae resulted in the samples with different shades. The soluble solids content was higher in the laboratory sample. The chemical composition the both samples were characterized by presenting a considerable amounts of carbohydrates, with amior percentage protein and ash, respectively, in the handmade and laboratory sample. In two samples showed a low content of lipids and the lipid profile showed a higher proportion of monounsaturated fatty acids, with the absence polyunsaturated handmade sample. The phytochemical screening by chemical reactions showed the presence of flavonoids, tannins, alkaloids and saponins the laboratory sample, presenting a greater diversity of bioactive compounds. Through of the analysis by thin layer chromatography was possible to identify the phytosterols β-sitosterol and stigmasterol the both samples, also suggest the presence of β-carotene and chlorophyll α the laboratory sample. The levels of total phenolics and flavonoids were more significant in the ethanol extract of the laboratory sample. The in vitro lethality showed that extracts of the laboratory sample and handmade from 125 to 500 μg/ mL, respectively, were highly lethal. In the evaluation of antioxidant capacity by the system β-carotene/ácido linoleic method and by DPPH radical scavernging assay, the ethanol extract from the laboratory process showed significantly greater activity than the other extracts, being and the first and second methods, respectively, lower and equivalent to the synthetic antioxidant BHT. The handmade ethanol extract has not demonstrated skill in deactivating free radicals, but showed activity in inhibiting lipid peroxidation, although the values were significantly lower than the laboratory sample. We conclude that the dehydration process in the laboratory is the most efficient technique to maintenance of the chemical composition present in the seaweed, providing beneficial properties such as antioxidant capacity. We emphasize that this property can be explored with the objective of adding commercial value to the final product, which will promote the expansion of production of this seaweed in the community of Rio do Fogo

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Kalanchoe brasiliensis Cambess (Crassulaceae), commonly known as saião , coirama branca , folha grossa , is originally from Brazil and commonly found in São Paulo to Bahia, mainly in the coastal zone. Regarding of biological activities, most preclinical studies were found in the literature, mainly about the anti-inflammatory activity of extracts obtained from leaves and / or aerial parts of K. brasiliensis. As regards the chemical constitution, it has been reported mainly the presence of flavonoids in the leaves of the species, but until this moment did not knows which are the active compounds. Although it is a species widely used in traditional medicine in Brazil, there is no monograph about the quality parameters of the plant drug. In this context, this study aims to characterize and quantify the chemical markers of hydroethanolic extract (HE) from the leaves of K. brasiliensis, which can be used in quality control of plant drug and derivatives obtained from this species. The methodology was divided into two parts: i. Phytochemical study: to fractionate, isolate and characterizate of the chemical (s) marker (s) of the HE from the leaves of K. brasiliensis; ii. To Developed validate of analytical method by High Performance Liquid Chromatography (HPLC)-diode array detector (DAD) to quantify the chemical (s) marker (s) of the EH. i. The EH 50% was prepared by turbo extraction method. It was then submitted to liquid-liquid partition, obtaining dichloromethane, n-butanol and ethyl acetate (AcOEt) fractions. The AcOEt fraction was selected to continue the fractionation process, because it has a chemical profile rich in flavonoids. The acOEt fraction was submitted to column chromatography using different systems for obtaining the compound Kb1. To identify this compound, it was submitted to UV analysis ii. For quantitative analysis, the EH was analyzed by HPLC, using different methods. After selecting the most appropriate method, which showed satisfactory resolution and symmetrical peaks, it was validated according to parameters in the RE 899/2003. As result, it was obtained from the AcOEt fraction the compound Kb1 (2.7 mg). Until this moment, the basic nucleus was characterized by UV analysis using shift reagents. The partial chemical structure of the compound Kb1 was identified as a flavonol, containing hydroxyls in 3 , 4 position (ring A), 5 and 7 free (ring B) and a replacement of the C3 hydroxyl by a sugar. As the analysis were performed in the HPLC coupled to a DAD, we observed that the UV spectrum of the major peaks of EH from K. brasiliensis shown similar UV spectrum. According to the literature, it has been reported the presence of patuletin glycosydes derivatives in the leaves of this species. Therefore, it is suggested that the compound Kb1 is glycosylated patuletin derivative. Probably the sugar (s) unit(s) are linked in the C3 in the C ring. . Regarding the development of HPLC analytical method, the system used consists of phase A: water: formic acid (99,7:0,3, v / v) and phase B: methanol: formic acid (99,7:0,3, v / v), elution gradient of 40% B - 58% B in 50 minutes, ccolumn (Hichrom ®) C18 (250x4, 0 mm, 5 μm), flow rate 0.8 mL / min, UV detection at 370 nm, temperature 25 ° C. In the analysis performed with the co-injection of thecompound Kb1 + HE of K. brasiliensis was observed that it is one of the major compounds with a retention time of 12.47 minutes and had a content of 15.3% in EH of leaves from K. brasiliensis. The method proved to be linear, precise, accurate and reproducible. According to these results, it was observed that compound Kb1 can be used as a chemical marker of EH from leaves of K. brasiliensis, to assist in quality control of drug plant and its derivatives

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Spondias sp. (Anacardiaceae), popularly known as cajá-umbu, is an endemic plant from Northeastern Brazil, where their leaves are widely used in folk medicine to treat inflammatory processes, while their fruits have a great agro industrial potential. This study was designed to evaluate hepatoprotective, antinociceptive, antioxidant, antimicrobial and anti-inflammatory properties, as well as the acute toxicity and repeated dose 28, using a methanolic extract (MES), a fraction rich in flavonoids (FRF) and a precipitate from Spondias sp.leaves. The antioxidant activity of them was valued to evaluate their free radical scavenger capacity by DPPH test, whereas MES and FRF were used to evaluate while the preventive action on carbon tetrachloride (CCl4)-induced hepatotoxicity. Seven groups (n=5) of female Wistar rats were used as follows: control group, CCl4-intoxicated group treated with EMS (500 mg/kg) for 7 days, three CCl4-intoxicated groups treated with FRF (25, 50 and 75 mg/kg) for 7 days and the CCl4-intoxicated group treated with Legalon ® (silimarina; (phytotherapeutic reference) (50 mg/kg; 7 days). MES and FRF showed a protective action against liver injury induced by CCl4, being observed a significant reduction of serum enzyme activity marker of liver damage (alanine transaminase and aspartate transaminase). On the other hand, the lipid peroxidation (SRAT) decrease, as well as the increase of glutathione content and enzyme activity of antioxidant defense system (SOD, CAT, GPx) toward near normal values indicated the ability of EMS to restore the oxidative imbalance induced by CCl4. The histological analysis confirmed the hepatoprotection, compared to degenerative changes in CCl4-treated group. This hepatoprotetor effect was similar to that shown by Legalon®. The in vitro high antioxidant capacity of extract (93.16 ± 1.00%) showed analogous results to those obtained by Carduus marianus BHT (reference standard). This fact explains the obtained results in vivo. Although no antimicrobial activity was detected, EMS and FRF promoted the antinociceptive effect induced in the second phase by the intraplantar formalin test, evidencing the anti-inflammatory action; confirmed by the carrageenan-induced peritonitis model. The evaluation of the mechanical allodynia (CFA a 80%) demonstrated the involvement of the Spondias sp. chemical composition in the anti-inflammatory activity toward the acute processes. The acute exposure and repeated dose during 28 days did not produce significant changes in the parameters that evaluate toxicity. Together the experimental results reveal, that Spondias sp. leaf extracts have a promising potential in pharmaceutical area, and due to its non-toxic condition present efficiency and security

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Licania rigida Benth., Licania tomentosa (Benth.) Fritsch, and Couepia impressa Prance (Chrysobalanaceae family) plants have long been used medicinally by the people from Northeastern Brazil. Crude extracts and infusions of these plants have been applied in the treatment of several conditions such as diabetes and rheumatism, degenerative diseases with involvement of reactive oxygen species (ROS). The aim of this study was to evaluate the aqueous, ethanolic, and hydroethanolic leaves extracts antioxidant capacity of these species, using several in vitro assay systems (reducing power, DPPH● scavenging, the β-carotene linoleate model system and lipid peroxidation inhibition in rat brain homogenate, using thiobarbituric acid reactive substances - TBARS). The oral acute toxicity of aqueous extracts was also evaluated in vivo. Results revealed that these extracts possess a potent reducing power and DPPH scavenging ability, as well as the ability to prevent TBARS formation in rat brain homogenate in a concentration-dependent manner. Regarding in vivo oral acute toxicity of the aqueous species extracts, no toxic effects were observed upon evaluating physiological, hematological and biochemical parameters. The presence of high levels of phenolics and flavonoids was determined mainly in the ethanol extract. However, the C. impressa hydroethanolic extract, fractionated with hexane, chloroform and ethyl acetate for analysis by NMR 1H, showed more efficient results than the reference antioxidant Carduus marianus. The classes of organics compounds were determined were phenolics in the fraction of ethyl acetate and terpenes in chloroform and hexane fractions. The ethil acetate fraction had the highest content of flavonoids and increased scavenging capacity of DPPH●, possibly by the presence of phenolic compounds. Therefore, a detailed investigation of the phytochemical composition and in vivo study of the C. impressa hydroethanolic extract is suggested to characterize the active compounds of the species

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In this present work an ethnographic research was performed with 84 native medicinal specimens from the Litoral Norte Riograndense, from which two plants Cleome spinosa Jacq e Pavonia varians Moric were submitted to ethnobotanic, phytochemistry and pharmacologic investigations. Additionally, a phytopharmacological research of the medicinal specimen Croton cajucara Benth ( native plant of the Amazon region of Brazil) was improved. The obtained phytochemical results of the C. spinosa and P. varians showed the presence of flavonoids constituents, among other components. The two flavonoids (2S)-5-hydroxy-7,4 -dimethoxy-flavanone and 5,4 -dihydroxy-3,7,3 -trimethoxy-flavone were isolated from C. spinosa. The antioxidant activity of the hydroalcoholic extracts of C. spinosa and P. varians solubilized in the microemulsion systems SME-1 and SME-4, was evaluated in the DPPHmethod. The used SME systems [obtained with Tween 80: Span 20 (3:1) and isopropyl myristate (IPM)] improved the dissolution of those tested polar extracts, with higher efficacy to the SME-1 system (in which ethanol was included as cosurfactant). The CE50 values evidenced for P. varians were 114 [g/mL (SME-1) and 246 [g/mL (SME-4); for C. spinosa it was 224 [g/mL (SME-1) and 248 [g/mL (SME-4), being the system SME-1 more effective for both tested extracts. The hydroalcoholic extracts of P. varians (HAE-PV) was also submitted to pharmacological screening for antinociceptive activity in animal models. The oral administration of this extract (100, 300 and 1000 mg/kg) inhibited the acetic acid-induced writhing in mice. The higher inhibition (74%) was evidenced to the 1000 mg/kg administered dose. Its effect on the central nervous system (CNS) was investigated by tail flick and formalin-method and reveled that it has negligible antinociceptive action on the CNS. After taking consideration of HAE-PV interaction, Pavonia varians Moric could be used as a potent analgesic agent in case of peripheral algesia, without affecting the CNS. The phytochemical study of the stem bark of Croton cajucara Benth lead to the isolation of 19-nor-clerodanetype diterpenes, as well as to the separation of its fixed oil FO-CC. This non polar oil material reveled to be rich in sesquiterpenes and 19-nor-clerodanes components. The biologic effect of OF-CC was evaluated in the development in vitro of the fungis phytopatogens such as Fusarium oxysporum, Rhizoctonia solani and Sclerotium rolfsii. Significant inhibitory effect of the tested fungis (at 0,2 mg.mL-1 dosage) were comproved. A Mass Spectrometry study of clerodane-type diterpenes was developed in order to identify characteristic fragments on mass spectrometra of both clerodane and 19-nor-clerodane presenting an α,β-insaturated carbonyl moiety at ring A of the decalin-system. For that study, mass spectroscopy data were analysed for 19-nor-clerodanes [trans-dehydrocrotonin (DCTN), trans-crotonin (CTN), cis-cajucarin B (c-CJC-B), and cajucarinolide (CJCR)] and for clerodanes [isosacacarin (ISCR) and transcajucarin A (t-CJC-A)] obtained from the stem bark of C. cajucara, and also clerodane-type from other species. The trans-junction of the enone-system clerodanes was clear correlated with the presence of the characteristic ions at m/z 95, 121 e 205. Meanwhile, the characteristics ions at m/z 122 e 124 were correlated to cis-junction. The trans-junction of the enone-system 19-nor-clerodanes showed characteristics ions at m/z 161, 134 e 121. This study could be successful employed for identification of clerodane constituents from other specimens without any additional spectroscopic analyses, as well as a previously phytochemical analyzes in clerodane project search

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This study conducted chemical analyzes of the fruits of Licania tomentosa Benth belonging to the Chrysobalanaceae family, order and superorder Rosiflorae Rosales. Samples were collected in February 2011 in the city of Natal - RN. The fruits were separated into peel, pulp and seed, and the samples were analyzed on moisture and ash by thermogravimetric methods, reducing and total sugars, lipids by Soxhlet extraction, minerals by ICP / OES and other analyzes by physical measurements of the fruit. The fruits for the analysis of determination of flavonoids and phenolic compounds were dried at 40 ° C and ground. For the analyzes to determine the content of phenolics and flavonols was used spectroscopy in the visible region, and also performed the characterization of ethanol extracts by high performance liquid chromatography and test for antioxidant activity hydroethanolic extracts. The results obtained are about 83.9% of the fruits have a length between 4.0 to 6.0 cm with respect to the diameter of the fruit about 97.4% of the fruits have a diameter between 2.0 - 4, 0 cm, mean weight of 36.14 g (7.86), the bark showed 60.5 (1.5)% relative humidity, the flesh 72.3 (0.9) and 44.4 seeds (0.4 )%, the bark showed 0.22 (0.00)% ash, the pulp 1.41 (0.01)% and the seed 1.18 (0.01)%, the bark showed 3.73 (0, 09) mg lipids / 100 g sample of the pulp 0.40 (0.04) and the seed 0.05 (0.00). With respect to reducing sugars and total gave the results, 16.23 (0.23) g/100g and 20.70 (0.24) g/100g. The fruit is presented with a good source of nutrients especially carbohydrates and lipids. The analysis for determining the antioxidant activity tests were performed reducing power and antioxidant capacity, the antioxidant capacity of hydroethanolic extracts of peel and pulp showed similar results, with higher concentrations however hydroethanolic bark extract. Regarding the content of phenolics and flavonoids hidroetanílico bark extract showed higher concentration values. The characterization of the extracts by high performance liquid chromatography identified the following compounds by retention time indicated by the race of the standards: galic acid, kaempferol and kaempferol derivatives. Considering the results of the fruit Licania tomentosa Benth may be an alternative food by analysis of their nutritional content and has substances with antioxidant action

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The increase in the incidence of fungal infections due to the drug-resistance or to the number of patients with immune alterations such as AIDS, chemotherapy or organ transplantation, has done the research necesseray for new antifungal drugs. The species from Northeastern Brazil may become an important source of innovative natural molecules. To evaluate the antifungal activity of 10 medicinal plants from Northeastern Brazil, traditionally used as antimicrobial agents, 30 crude extracts (CE) were tested in vitro against four standard species of Candida spp. The CE most promising of these plants were evaluated against yeasts of the oral cavity of kidney transplant patients and through a bioassay-guided fractionation. The extracts form leaves of E. uniflora, the stem bark of L. ferrea and leaves of P. guajava showed significant activity against all yeasts evaluated, with MIC values between 15.62 and 62.5 μg/mL. E. uniflora also showed fungicidal properties against all yeasts, especially against Candida dubliniensis. In patients with immune systems compromised, such as transplanted, oral candidiasis manifests mainly due to immunosuppressive therapy, and resistance to conventional antifungals. The CE of E. uniflora presented range of MIC values between 1.95 to 1000 μg/mL, and lower MIC50 and MIC90 values were observed against C. non-albicans. Due the better results, the CE of E. uniflora was elected to performe the bioassay-guided fractionation. Thus it was possible to obtain enriched fractions, which showed good inhibitory ability against ATCC strains of Candida spp. It was also possible to perform experiments to verify the production of biofilm in two strains of C. dubliniensis and action of extracts and fractions on the same. With this, we observed a behavior between the yeast ATCC and clinical isolate. In addition, CE, fractions and subfractions of E. uniflora inhibit planktonic cells to preventing the growth of biofilm. The preliminary chemical characterization of the fractions obtained revealed the presence of polyphenols (especially flavonoids and tannins). Finally, the results suggests that among the plant species studied, E. uniflora showed a pattern very promising as regards the antifungal, requiring further study of purification and structural elucidation of compounds in order to verify that the antifungal effect found can be attributed to a specific compound or some mechanism depends on synergistic the mixture of polyphenols