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Dive into the research topics where Marc François Richter is active.

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Featured researches published by Marc François Richter.


Journal of Chromatography A | 2008

Pressurized liquid extraction of vitamin E from Brazilian grape seed oil

Lisiane dos Santos Freitas; Rosângela Assis Jacques; Marc François Richter; Andreia Loviane Silva; Elina Bastos Caramão

The goal of this paper is to optimize the pressurized liquid extraction (PLE) of vitamin E from grape seed oil from residues of the wine industry. For this purpose an experimental planning to optimize the extraction of Brazilian grape seed oil by means of PLE with hexane as solvent was applied and the results are compared with conventional methods (Soxhlet and mechanical press extraction). Vitamin E was separated and analyzed using HPLC with UV detection. This study demonstrates the ability of the PLE in extracting grape seed oil rich in vitamin E.


Plant Foods for Human Nutrition | 2011

Antigenotoxicity and Antioxidant Activity of Acerola Fruit (Malpighia glabra L.) at Two Stages of Ripeness

Roberta da Silva Nunes; Vivian Francília Silva Kahl; Merielen da Silva Sarmento; Marc François Richter; Letícia V. Costa-Lotufo; Felipe Augusto Rocha Rodrigues; Juan Andres Abin-Carriquiry; Marcela Martínez; Scharline Ferronatto; Alexandre de Barros Falcão Ferraz; Juliana da Silva

Genotoxic and antigenotoxic effects of acerola fruit at two stages of ripeness were investigated using mice blood cells. The results show that no ripeness stage of acerola extracts presented any genotoxic potential to damage DNA (Comet assay) or cytotoxicity (MTT assay). When antigenotoxic activity was analyzed, unripe fruit presented higher DNA protection than ripe fruit (red color) extract. The antioxidant capacity of substances also showed that unripe samples inhibit the free radical DPPH more significantly than the ripe ones. The results about determination of compounds made using HPLC showed that unripe acerola presents higher levels of vitamin C as compared to ripe acerola. Thus, vitamin C and the complex mixture of nutrients of Malpighia glabra L., and especially its ripeness stages, influenced the interaction of the fruit extract with the DNA. Acerola is usually consumed when ripe (red fruit), although it is the green fruit (unripe) that has higher potential as beneficial to DNA, protecting it against oxidative stress.


Journal of Photochemistry and Photobiology B-biology | 2009

Protective effects of three extracts from Antarctic plants against ultraviolet radiation in several biological models

Betina Kappel Pereira; Renato Moreira Rosa; Juliana da Silva; Temenouga N. Guecheva; Iuri Marques de Oliveira; Martus Ianistcki; Vinícius Cosmos Benvegnú; Gabriel Vasata Furtado; Alexandre de Barros Falcão Ferraz; Marc François Richter; Nádia Teresinha Schröder; Antonio Batista Pereira; João Antonio Pêgas Henriques

The photoprotective effect of the methanolic extracts of three Antarctic plant species - Deschampsia antarctica Desv., Colobanthus quitensis (Kunth) Bartl., and Polytrichum juniperinum Hedw. against UV-induced DNA damage was investigated in hamster lung fibroblasts (V79 cells) and in a biomonitor organism Helix aspersas, using comet assay. The protective, mutagenic, and antimutagenic profiles of these extracts were also evaluated using haploid strains of the simple eukaryote Saccharomyces cerevisiae, and antioxidant activity were investigated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, as well as the hypoxanthine/xanthine oxidase assay. At the concentration range employed, the extracts were not cytotoxic or mutagenic to S. cerevisiae. In addition, the treatment with these extracts enhanced survival, and decreased induced reverse, frameshift, and forward mutations in a dose-response manner in all UVC doses employed. The plants extracts did not generate DNA strand breaks in V79 cells, and the treatment significantly decreased DNA damage induced by UVC. Extracts significantly decreased UVC-induced lipid peroxidation in V79 cells, showing a clear antioxidant property. Moreover, results of comet assay in V79 cells, employing Fpg, Endo III, and Endo V enzymes, demonstrated significant reduction of UVC-induced DNA damage after pre-incubation with these extracts. The treatment with all tested extracts were much less efficient against UVC-induced cytotoxicity in the yeast strain defective in photolyase as compared to the wild type strain, suggesting that this DNA repair pathway is stimulated by substances present in the extracts. All extracts showed a significant inhibitory effect in the hypoxanthine/xanthine oxidase assay, and they had the ability to scavenge DPPH. In H. aspersas, the treatment was able to protect against UVC-induced damage. In conclusion, D. antarctica, C. quitensis, and P. juniperinum extracts present photoprotective properties, which can be attributed to molecules, such as flavonoids and carotenoids, which act as UV-absorbing molecules and as antioxidants, as well as stimulate DNA-repair processes.


Pharmaceutical Biology | 2011

Pharmacological evaluation of Copaifera multijuga oil in rats

Cristine Kobayashi; Tiago Oselame Fontanive; Bárbara Grade Enzweiler; Laura Renata de Bona; Thalita Massoni; Miriam Anders Apel; Amelia Teresinha Henriques; Marc François Richter; Patrícia Ardenghi; Edna Sayuri Suyenaga

Context: Copaiba oil is an oleoresin made up of resin acids and volatile compounds, and it is obtained by tapping the trunks of trees that are members of the Copaifera L. (Leguminoseae) genus and are found in tropical parts of Latin America. Objective: This study analyzed the chemical composition of Copaifera multijuga Hayne oil and conducted preclinical trials to investigate anti-inflammatory effects and any action it may have on the central nervous system (CNS) of rats. Materials and methods: The chemical analysis was carried out using gas chromatography with mass spectroscopy. Anti-inflammatory activity was measured by leucocytes mobilization, by chemotaxis assay in Boyden’s chamber, and by pleurisy model in rats. CNS effect was determined by plus maze and open-field assays. The statistical test applied was analysis of variance (ANOVA) followed by Tukey’s test or ANOVA followed by Duncan’s test. Results: The oil was composed of sesquiterpenes with the predominance of β-caryophyllene (36.0%), followed by α-copaene (18.8%), β-bisabolene (8.5%), and α-trans-bergamotene (7.0%). Data demonstrated that at 100 and 200 mg/kg doses and at a concentration of 200 μl/ml copaiba essential oil presented anti-inflammatory effects both in vivo and in vitro based on reduced leukocyte migration to the rats’ pleural cavity and to the chemotactic agent lipopolysaccharide solution, respectively. During the experiments investigating CNS effects, locomotive and exploratory activities were reduced and the animals’ anxiety increased at 100 and 200 mg/kg. Conclusion: The results obtained suggest that copaiba oil has an interesting anti-inflammatory effect and important effect on the CNS.


Experimental Diabetes Research | 2010

Effect of Agaricus blazei Murill on the Pulmonary Tissue of Animals with Streptozotocin-Induced Diabetes

Fábio Cangeri Di Naso; Rodrigo Noronha de Mello; Silvia Bona; Alexandre Simões Dias; Marilene Porawski; Alexandre de Barros Falcão Ferraz; Marc François Richter; Norma Anair Possa Marroni

The present study was designed to evaluate the oxidative stress as well as the therapeutic effect of Agaricus blazei Muril (A. Blazei) in rats with streptozotocin-induced diabetes. We used 25 Wistar rats, and DM was induced by injecting streptozotocin (70 mg/Kg i.p.). Agaricus blazei Muril was administered daily starting 40 days after disease onset. A. Blazei was tested as an aqueous extract for its phytochemical composition, and its antioxidant activity in vitro was also evaluated. Lipoperoxidation (LPO), and superoxide dismutase (SOD), catalase, and glutathione peroxidase activities were measured in the pulmonary tissue, as well as the presence of inducible nitric oxide synthase (iNOS), through immunohistochemistry. An anatomopathologic study was also performed. Phytochemical screening of A. Blazei detected the presence of alkaloids and saponins. The extract exhibited a significant antioxidant activity in the DPPH-scavenging and the hipoxanthine/xanthine oxidase assays. Pulmonary LPO increased in diabetic animals (0.43 ± 0.09; P < .001) as compared to the control group (0.18 ± 0.02), followed by a reduction in the A. Blazei-treated group (0.33 ± 0.04; P < .05). iNOS was found increased in the lung in diabetic rats and reduced in the A. Blazei-treated group. The pulmonary tissue in diabetic rats showed oxidative alterations related to the streptozotocin treatment. The A. Blazei treatment effectively reduced the oxidative stress and contributed to tissue recovery.


Journal of Food Science | 2013

In Vivo Genotoxicity Evaluation of an Artichoke (Cynara scolymus L.) Aqueous Extract

Meriele A. Zan; Alexandre de Barros Falcão Ferraz; Marc François Richter; Jaqueline Nascimento Picada; Heloísa Helena Rodrigues de Andrade; Mauricio Lehmann; Rafael Rodrigues Dihl; Emilene Nunes; Juliane Garcia Semedo; Juliana da Silva

UNLABELLED The Cynara scolymus (artichoke) is widely consumed as tea or food and shows important therapeutic properties. However, few studies have assessed the possible toxic effects of artichoke extracts. This study evaluates genotoxic and mutagenic activities of artichoke leaf aqueous extract in mice using the comet assay and the micronucleus test. Leaf extracts were given by gavage (500 mg/kg, 1000 mg/kg, and 2000 mg/kg) for 3 consecutive days. Extract composition was investigated using phytochemical screening and high-performance liquid chromatography (HPLC). In addition, antioxidant capacity was analyzed through the diphenyl-picrylhydrazyl (DPPH) and xanthine oxidase assay. Phytochemical screening detected the presence of phenolic compounds, flavonoids, and saponins. HPLC analyses indicated the presence of chlorogenic acid, caffeic acid, isoquercetrin, and rutin. Extracts showed a dose-dependent free radical scavenging effect of DPPH and an inhibitory effect of xanthine oxidase. The genotoxic results showed that leaf extracts did not increase micronuclei in peripheral blood cells. Compared to the control group, a significant increase in comet assay values was observed only in bone marrow of group treated with 2000 mg/kg, the highest dose tested, indicating that artichoke tea should be consumed with moderation. PRACTICAL APPLICATION This is the first report of in vivo mutagenic and genotoxic evaluation with C. scolymus. The present study revealed leaf aqueous extract from artichoke shows lack of mutagenicity in vivo, and low genotoxicity and antioxidant activity; indicating that artichoke tea should be consumed with moderation.


BioMed Research International | 2012

Treatment with aqueous extract from Croton cajucara Benth reduces hepatic oxidative stress in streptozotocin-diabetic rats.

Graziella Rodrigues; Fábio Cangeri Di Naso; Marilene Porawski; Éder Marcolin; Nelson A. Kretzmann; Alexandre de Barros Falcão Ferraz; Marc François Richter; Claudio Augusto Marroni; Norma Anair Possa Marroni

Croton cajucara Benth is a plant found in Amazonia, Brazil and the bark and leaf infusion of this plant have been popularly used to treat diabetes and hepatic disorders. The present study was designed to evaluate the oxidative stress as well as the therapeutic effect of Croton cajucara Benth (1.5 mL of the C. cajucara extract i.g.) in rats with streptozotocin-induced diabetes. Croton cajucara Benth was tested as an aqueous extract for its phytochemical composition, and its antioxidant activity in vitro was also evaluated. Lipid peroxidation and superoxide dismutase, catalase, and glutathione reductase activities were measured in the hepatic tissue, as well as the presence activation of p65 (NF-κB), through western blot. Phytochemical screening of Croton cajucara Benth detected the presence of flavonoids, coumarins and alkaloids. The extract exhibited a significant antioxidant activity in the DPPH-scavenging and the hypoxanthine/xanthine oxidase assays. Liver lipid peroxidation increased in diabetic animals followed by a reduction in the Croton-cajucara-Benth-treated group. There was activation of p65 nuclear expression in the diabetic animals, which was attenuated in the animals receiving the Croton cajucara Benth aqueous extract. The liver tissue in diabetic rats showed oxidative alterations related to the streptozotocin treatment. In conclusion the Croton cajucara Benth aqueus extract treatment effectively reduced the oxidative stress and contributed to tissue recovery.


Journal of Toxicology and Environmental Health | 2013

Evaluation of the Mutagenicity and Genotoxicity of Arrabidaea chica Verlot (Bignoneaceae), an Amazon Plant with Medicinal Properties

Vinícius Carlotto dos Santos; Thais Basso Longo; Ana Letícia Hilario Garcia; Marc François Richter; Temenouga N. Guecheva; João Antonio Pêgas Henriques; Alexandre de Barros Falcão Ferraz; Jaqueline Nascimento Picada

Arrabidaea chica Verlot (Bignoniaceae) is an important folk medicine plant native to the Amazon region and used to treat anemia, hemorrhage, inflammation, intestinal colic, hepatitis, and skin affections. Although studies showed its therapeutic properties, little knowledge regarding genotoxic properties of this plant is available. The aim of this study was to determine the potential mutagenic and genotoxic/antigenotoxic effects of an A. chica chloroformic fraction (Ac-CF) obtained from leaves containing bioactive metabolites. The mutagenic effects were evaluated using the Salmonella mutagenicity assay, with TA98, TA97a, TA100, TA102, and TA1535 strains, with and without metabolic activation. In vivo mutagenic and genotoxic/antigenotoxic effects were investigated using the micronucleus (MN) test in bone marrow and alkaline comet assay in blood and liver after administration of 100, 500, or 1000 mg/kg Ac-CF in CF-1 mice by gavage (once a day for 3 d). In vitro antioxidant potential was evaluated using DPPH and xanthine/hypoxanthine assays. Ac-CF was not mutagenic in any of the Salmonella typhimurium strains tested and showed negative responses for mutagenicity and genotoxicity in mice. Further, Ac-CF displayed antigenotoxic effects by decreasing the oxidative DNA damage induced by hydrogen peroxide by greater than 50% in blood and liver. The antioxidant action detected in the in vitro assays demonstrated IC50 of 0.838 mg/ml in the xanthine/hypoxanthine assay and IC50 of 28.17 μg/ml in the DPPH assay. In conclusion, Ac-CF did not induce mutagenic and genotoxic effects and was able to protect DNA against oxidative damage in vivo, suggesting that this fraction may not pose genetic risks, although further toxicology assays are necessary. This work was supported by CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico); FAPERGS (Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul); and GENOTOX-ROYAL, Brazil.


Revista Brasileira De Farmacognosia-brazilian Journal of Pharmacognosy | 2010

Influência dos processos de secagem sobre o teor de flavonoides e na atividade antioxidante dos extratos de Baccharis articulata (Lam.) Pers., Asteraceae

Jackson Borgo; Carlos Augusto Xavier; Dinara Jaqueline Moura; Marc François Richter; Edna Sayuri Suyenaga

The objective of this work was to verify the influence of different drying processes on the levels of quercetin of the aerial parts of Baccharis articulata (Lam.) Pers., Asteraceae, as well as the evaluation of the in vitro antioxidant activity of these extracts. We demonstrated that the highest concentration of this flavonoid was detected in oven-dried samples, although there no significant difference in their pharmacological activity of all analyzed samples could be shown.


Genetics and Molecular Biology | 2014

Effects of artichoke (Cynara scolymus) leaf and bloom head extracts on chemically induced DNA lesions in Drosophila melanogaster

Laura Vicedo Jacociunas; Rafael Rodrigues Dihl; Mauricio Lehmann; Alexandre de Barros Falcão Ferraz; Marc François Richter; Juliana da Silva; Heloísa Helena Rodrigues de Andrade

The genotoxicity of bloom head (BHE) and leaf (LE) extracts from artichoke (Cynara scolymus L.), and their ability to modulate the mutagenicity and recombinogenicity of two alkylating agents (ethyl methanesulfonate – EMS and mitomycin C – MMC) and the intercalating agent bleomycin (BLM), were examined using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. Neither the mutagenicity nor the recombinogenicity of BLM or MMC was modified by co- or post-treatment with BHE or LE. In contrast, co-treatment with BHE significantly enhanced the EMS-induced genotoxicity involving mutagenic and/or recombinant events. Co-treatment with LE did not alter the genotoxicity of EMS whereas post-treatment with the highest dose of LE significantly increased this genotoxicity. This enhancement included a synergistic increase restricted to somatic recombination. These results show that artichoke extracts promote homologous recombination in proliferative cells of D. melanogaster.

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Jenifer Saffi

Universidade Luterana do Brasil

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Juliana da Silva

Universidade Luterana do Brasil

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Jaqueline Nascimento Picada

Universidade Federal do Rio Grande do Sul

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João Antonio Pêgas Henriques

Universidade Federal do Rio Grande do Sul

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Mauricio Lehmann

Universidade Luterana do Brasil

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Rafael Rodrigues Dihl

Universidade Luterana do Brasil

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Éder Marcolin

Universidade Federal do Rio Grande do Sul

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Norma Anair Possa Marroni

Universidade Federal do Rio Grande do Sul

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