A própolis é um produto viscoso produzido e coletado por abelhas operárias, a partir de brotos ou... more A própolis é um produto viscoso produzido e coletado por abelhas operárias, a partir de brotos ou exsudatos de plantas, utilizados para proteção da colmeia. O objetivo deste trabalho foi realizar o perfil fitoquímico e a atividade biológica da própolis de abelha sem ferrão (ASF) Melipona quadrifasciata (Mandaçaia) nativa do Rio Grande do Sul, Brasil. A própolis apresentou concentração fenólica total de 126,52 mg g-1, e os principais compostos fenólicos identificados foram ácido p-cumárico (35,64 mg g-1) e ácido gálico (18,33 mg g-1). Os carotenóides β-caroteno, β-criptoxantina, luteína e licopeno foram identificados na própolis de M. quadrifasciata, sendo que o β-caroteno apresentou a maior concentração (1,56 mg/100g). Os compostos voláteis foram obtidos por headspace e identificados por CG/EM, sendo o α-pineno o composto majoritário, seguido de limoneno, silvestreno e β-pineno. A própolis apresentou alta atividade antiradicalar pelo método DPPH, com EC50 de 2,29 µg mL-1, atividade ...
Manejo de Agroecossistemas e Agricultura Orgânica Resumo A alelopatia pode ser definida como a in... more Manejo de Agroecossistemas e Agricultura Orgânica Resumo A alelopatia pode ser definida como a interferência de uma planta sobre o desenvolvimento de outra, pela liberação ou decomposição de substâncias químicas. O objetivo do trabalho foi avaliar extratos alcoólicos e aquosos da parte aérea de Borreria palustris, sobre a germinação de sementes de feijão e pepino. As sementes foram germinadas em rolos de papel. Para cada tratamento foram usadas 20 sementes em 10 repetições. Os rolos foram colocados em germinadores a 25°C e fotoperíodo de 12 horas, por sete dias. Foram avaliadas plântulas normais e anormais, sementes não germinadas, comprimento de parte aérea e raízes das plântulas de pepino e feijão. Os Resultados sofreram transformação, y = √(arcsen(%/100)). A Borreria inibiu a germinação das sementes e o desenvolvimento das raízes de pepino. Não afetou o crescimento das raízes de feijão e estimulou o crescimento da parte aérea das mesmas. Ressalta-se a necessidade de estudos químicos dos extratos da Borreria e a continuidade das avaliações.
As pesquisas que definem a estrutura da cadeia produtiva da palmeira juçara (Euterpe edulis Mart.... more As pesquisas que definem a estrutura da cadeia produtiva da palmeira juçara (Euterpe edulis Mart.), nativa da Mata Atlântica, ainda são muito restritas. O objetivo do presente trabalho foi mapear a cadeia do açaí juçara, caracterizar cada elo do processo produtivo e identificar potencialidades e dificuldades dessa cadeia. A pesquisa delimita-se na região do Litoral Norte do Estado do Rio Grande do Sul e apresenta os resultados das entrevistas sobre a produção e comercialização da juçara nesta região. Nesta pesquisa foi possível obter uma estimativa de dados sobre o número e localização dos produtores, e da comercialização do açaí juçara nos diversos canais de distribuição. Os resultados gerais da pesquisa indicam que, no caso do produtor, foram detectadas deficiências no manejo e dificuldades com relação ao extrativismo do palmito.
The present study aimed to determine the chemical composition and biological activity of the esse... more The present study aimed to determine the chemical composition and biological activity of the essential oil obtained from Phyllogonium viride Brid. (Phyllogoniaceae, Bryophyta), whose samples were collected in southern Brazil. For the first time, the cytotoxic activity of the essential oil of P. viride in breast and colorectal tumor cells (MCF‐7 and HCT‐116) was evaluated, as well as the cytotoxic potential of this oil in non‐tumoral cells of human immortalized keratinocytes (HaCaT) via MTT assay. The compounds majorly found in P. viride essential oil were β‐bazzanene (20.30 %), β‐caryophyllene (17.06 %), β‐chamigrene (14.02), and germacrene B (11.72 %). Treatment with P. viride essential oil in the different tested cell lines did not induce any toxicity in most of the tested concentrations. These data contribute to generating new scientific information about this understudied plant species. Furthermore, the chemical characterization of the compounds present in the essential oil of P. viride can lead to greater elucidation of its biotechnological potential.
The Cunila angustifolia essential oil was obtained from fresh leaves by hydrodistillation and ana... more The Cunila angustifolia essential oil was obtained from fresh leaves by hydrodistillation and analyzed by GC‐FID and GC‐MS to determine its chemical composition. The essential oil presented pulegone (29.5 %) and isomenthol (27.0 %) as major components, and other compounds such as menthone (8.6 %), neomenthol (7.2 %), menthyl acetate (2.5 %) and caryophyllene oxide (2.0 %) were identified. The cytotoxic activity of the essential oil was evaluated by MTS assay, with the human cancer cell lines of the lung (A549), breast (MCF‐7) and skin melanoma (SK‐Mel‐28). The assay showed the highest selectivity, to MCF‐7 cell lines, with IC50 equal to 34.0 μg mL−1, low selectivity for SK‐Mel‐28 cell lines, with IC50 equal to 279.9 μg mL−1, and no mortality to A549 cell lines.
Raman spectroscopy is a rapid and non-destructive analytical technique that has found a growing i... more Raman spectroscopy is a rapid and non-destructive analytical technique that has found a growing interest in the characterization and quantification of microconstituents in foods. In this work, Raman spectroscopy was used to evaluate the carotenoids content of processed Bunchosia Glandulifera, a native fruit from the Brazilian Atlantic Forest. The B. glandulifera pulps were dried in hot air at 65 and 85 °C, resulting in carotenoids degradation of about 75 and 80%, respectively. The degradation profile of carotenoids over time was analyzed by Raman spectroscopy, with and without the use of an internal standard (TiO 2). The reproducibility of the analyses was evaluated by PCA of spectral data. PLS regression was applied for modelling the total carotenoids in B. glandulifera. Resulting models show the Raman data correlate with carotenoids content on samples resulting in a satisfactory coefficient of determination for all sets of samples.
The orange-fleshed sweet potato is a vegetable-rich in carotenoids. The thermic treatment for swe... more The orange-fleshed sweet potato is a vegetable-rich in carotenoids. The thermic treatment for sweet potato processing can decrease the content of these constituents in the foods, lowering their bioactive properties. Raman spectroscopy has been growing as a fast tool to food analysis, especially for detection of low concentrations of carotenoids and to the monitoring of its degradation profile over time. Therefore, in this work were evaluated two methods of drying, hot air and microwaving with rotary drum, combined with quantitative Raman spectroscopy. The results showed carotenoids degradation around 50 % for both types of drying processes studied. PCA plot proved the potential of reproducibility of analyses for microwave drying samples. For samples heated with hot air, the best linear correlation achieved was R 2 = 0.90 and by microwave was R 2 = 0.88. Also, partial least squares (PLS) regression models were constructed obtaining a satisfactory coefficient of determination.
Rapanea ferruginea antioxidant and antitumoral properties were not explored before in literature.... more Rapanea ferruginea antioxidant and antitumoral properties were not explored before in literature. This study aimed to investigate these biological activities for the R. ferruginea leaf extract and correlate them with its phenolic content and influence in biological membrane dynamics. Thus, in this study, anti/pro-oxidative properties of R. ferruginea leaf extract by in vitro DPPH and TBARS assays, with respect to the free radical reducing potential and to its activity regarding membrane free radical-induced peroxidation, respectively. Furthermore, preliminary tests related to the extract effect on in vitro glioma cell viability were also performed. In parallel, the phenolic content was detected by HPLC-DAD and included syringic and trans-cinnamic acids, quercetrin, catechin, quercetin, and gallic acid. In an attempt to correlate the biological activity of R. ferruginea extract and its effect on membrane dynamics, the molecular interaction between the extract and a liposomal model wi...
Optimization of electrochemical methods for total antioxidant capacity (TAC) determination of Bun... more Optimization of electrochemical methods for total antioxidant capacity (TAC) determination of Bunchosia glandulifera (Jacq.) Kunth (Malpighiaceae) extracts was performed. Other methods for antioxidant studies were also used for comparison with the results obtained by electrochemical assays. The extracts exhibited good solubility in the aprotic solvent dimethylsulfoxide. Hence, two electrochemical methods, namely cyclic (C) and differential pulse (DP) voltammetry (V) were optimized for TAC determination in this medium and by using ascorbic acid. The CV presented better linearity than DPV in the optimum conditions. TAC values determined by ABTS, FRAP and DPPH increased in the order seed < pulp < bark < leaf < root extract, in generally the same order observed by CV, indicating the applicability of the method in these conditions. The phenolic compounds contents were 302±10, 327±11, 1,008±71, 4,003±13 and 7,502±30 mg gallic acid/100 g extract, respectively, increasing in the same order as observed for TAC. On the other hand, such order disagreed with the amounts of major antioxidant vitamins, carotenoids and ascorbic acid, estimated in these extracts, which corresponded, by comparison with the contents of phenolic compounds, to 0.62, 34, 9.9, 0.39 and 0.86 %, respectively. Thus, it can be inferred that specially in the case of roots and leaves, the contents of phenolic compounds may have greater contribution for their TAC values.
Resumo O estudo do processo de secagem foi realizado a partir da utilização de técnicas de planej... more Resumo O estudo do processo de secagem foi realizado a partir da utilização de técnicas de planejamento experimental investigando os seguintes fatores temperatura de secagem (30 a 80 °C), massa da amora (6,0 a 135 g) e tempo (16 a 24 h), tendo como variável de resposta a umidade e concentração dos compostos fenólicos. Também foram fixados os fatores: tipo de amostra (triturada) e estufa (com circulação de ar) para realização dos ensaios experimentais. Os resultados mostraram perdas pequenas de compostos bioativos no processo a 55 °C por 16 horas com 80 g de amostra. De acordo com as análises químicas, a farinha encontra-se dentro dos padrões exigidos pela legislação brasileira para farinhas (máximo de 15%), podendo ser classificada como produto de alto percentual de fibra (24,33±2,88 g/100 g de farinha). Foram determinadas na farinha através de métodos espectrofotométricos: Fenólicos Totais: 344,94 mg GAE/100 g; Flavonoides Totais 182,82 mg Ce/100 g; Antocianinas Totais 77,93 mg/100...
An expedient, palladium-mediated cross-coupling approach to functionalize the benzimidazole-based... more An expedient, palladium-mediated cross-coupling approach to functionalize the benzimidazole-based core under microwave-assisted conditions has been developed and is described. This protocol, which incorporates appendage diversity on this potential scaffold, is found to be compatible with a wide range of electronicallyand sterically-divergent (hetero)aryl boronic acids. The use of the PdCl2/(SPhos) catalytic system allows the formation of a stable and highly active LPd(0) species which was found to be critical for the successful synthesis of these novel, pharmacologically-relevant molecules.
The maize weevil, Sitophilus zeamais is a major pest of stored grain whose control has been perfo... more The maize weevil, Sitophilus zeamais is a major pest of stored grain whose control has been performed with the use of synthetic insecticides, which in many cases are being banned due to issues involving risks to human and animal health and to the environment. In order to avoid the use of these insecticides, alternative control has been sought, including the use of plant extracts. In this study, “poejo”, Cunila angustifolia leaves extracts and essential oils have been used against S. zeamais. The results of the bioassay for the control of S. zeamais showed statistical significance (P <0.05) for all sources of variation. The essential oil reached 100% efficiency at all different concentrations, the hexane extract at 0.32% showed 38.70% efficiency, while the aqueous and crude extracts showed no insecticidal effect on adults of S. zeamais. The highest mortality rate was found after 96 h of application of the extracts.
A composição química do óleo volátil das folhas de três matrizes de D. frutescens, coletadas no p... more A composição química do óleo volátil das folhas de três matrizes de D. frutescens, coletadas no período de um ano foi determinada por cromatografia gasosa-espectrometria de massas (GC-MS) e cromatografia gasosa com detector de ionização de chama (GC-FID). Os óleos voláteis da espécie foram caracterizados predominantemente por norisoprenóides (β-damascenona, β-ionona e α-ionona), seguida da ocorrência de sesquiterpenos. Através da análise multivariada foi observado que os compostos β-damascenona e β-ionona influenciaram de forma intensa a composição dos óleos voláteis e que espécies coletadas na mesma cidade apresentaram composição química similar. The chemical composition of the volatile oil from the leaves of three specimens of D. frutescens, collected over a period of one year, was determined by gas chromatography-mass spectrometry (GC-MS) and gas chromatography with flame ionization detection (GC-FID). These essential oils were characterized by the presence of norisoprenoids (β-damascenone, β-ionone, and α-ionone), as well as sesquiterpenes. Multivariate analysis showed that the compounds β-damascenone and β-ionone exerted the greatest influence on spatial and temporal differences in the composition of the oils. Samples obtained from specimens located in the same city showed similar chemical compositions.
The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is... more The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is a large tree, and its wood is used as a reservoir for distilled spirits, especially Cachaça. In this pioneering work, the essential oil was extracted monthly from the leaves of M. frondosus, for a period of 1 year. The essential oil was extracted by using hydrodistillation and the determination of the chemical composition of essential oil was performed by using the chromatographic techniques GC-FID and GC-MS. Thirty-three compounds were identified in the essential oil and bicyclogermacrene was the major compound. Through multivariate analysis, it was determined that β-caryophyllene, limonene and terpinen-4-ol were directly proportional to climatic factors. The yield of the oil was directly proportional to temperature and radiation.
Foi avaliada a atividade antioxidante pelo Sistema β-caroteno/Ácido Linoleico, ensaio do radical ... more Foi avaliada a atividade antioxidante pelo Sistema β-caroteno/Ácido Linoleico, ensaio do radical DPPH• (2,2-difenil-1-picrilhidrazila), do extrato bruto (EB) e frações hexânica (FH), clorofórmica (FC) e acetato de etila (FA) das pimentas malagueta (C. frutescens), cambuci (C. baccatum var. pendulum), cumari (C. baccatum var praetermissum) e pimentão magali (C. annuum var. annuum). As concentrações de capsaicinoides e de fenólicos totais presentes nas pimentas também foram determinadas. Os resultados obtidos demonstraram que as FC e FA das pimentas apresentaram maior concentração de fenólicos totais e capsaicinoides, sendo que a pimenta cumari foi a espécie com maior concentração destes compostos. A melhor atividade antioxidante pelo Sistema β-caroteno/Ácido Linoleico, foi obtida para o EB e FA da pimenta cambuci, seguida do EB da pimenta malagueta. Pelo método DPPH a FC e FA apresentaram menores valores de EC50, sendo a pimenta cumari e cambuci as mais efetivas. Estes resultados dem...
A própolis é um produto viscoso produzido e coletado por abelhas operárias, a partir de brotos ou... more A própolis é um produto viscoso produzido e coletado por abelhas operárias, a partir de brotos ou exsudatos de plantas, utilizados para proteção da colmeia. O objetivo deste trabalho foi realizar o perfil fitoquímico e a atividade biológica da própolis de abelha sem ferrão (ASF) Melipona quadrifasciata (Mandaçaia) nativa do Rio Grande do Sul, Brasil. A própolis apresentou concentração fenólica total de 126,52 mg g-1, e os principais compostos fenólicos identificados foram ácido p-cumárico (35,64 mg g-1) e ácido gálico (18,33 mg g-1). Os carotenóides β-caroteno, β-criptoxantina, luteína e licopeno foram identificados na própolis de M. quadrifasciata, sendo que o β-caroteno apresentou a maior concentração (1,56 mg/100g). Os compostos voláteis foram obtidos por headspace e identificados por CG/EM, sendo o α-pineno o composto majoritário, seguido de limoneno, silvestreno e β-pineno. A própolis apresentou alta atividade antiradicalar pelo método DPPH, com EC50 de 2,29 µg mL-1, atividade ...
Manejo de Agroecossistemas e Agricultura Orgânica Resumo A alelopatia pode ser definida como a in... more Manejo de Agroecossistemas e Agricultura Orgânica Resumo A alelopatia pode ser definida como a interferência de uma planta sobre o desenvolvimento de outra, pela liberação ou decomposição de substâncias químicas. O objetivo do trabalho foi avaliar extratos alcoólicos e aquosos da parte aérea de Borreria palustris, sobre a germinação de sementes de feijão e pepino. As sementes foram germinadas em rolos de papel. Para cada tratamento foram usadas 20 sementes em 10 repetições. Os rolos foram colocados em germinadores a 25°C e fotoperíodo de 12 horas, por sete dias. Foram avaliadas plântulas normais e anormais, sementes não germinadas, comprimento de parte aérea e raízes das plântulas de pepino e feijão. Os Resultados sofreram transformação, y = √(arcsen(%/100)). A Borreria inibiu a germinação das sementes e o desenvolvimento das raízes de pepino. Não afetou o crescimento das raízes de feijão e estimulou o crescimento da parte aérea das mesmas. Ressalta-se a necessidade de estudos químicos dos extratos da Borreria e a continuidade das avaliações.
As pesquisas que definem a estrutura da cadeia produtiva da palmeira juçara (Euterpe edulis Mart.... more As pesquisas que definem a estrutura da cadeia produtiva da palmeira juçara (Euterpe edulis Mart.), nativa da Mata Atlântica, ainda são muito restritas. O objetivo do presente trabalho foi mapear a cadeia do açaí juçara, caracterizar cada elo do processo produtivo e identificar potencialidades e dificuldades dessa cadeia. A pesquisa delimita-se na região do Litoral Norte do Estado do Rio Grande do Sul e apresenta os resultados das entrevistas sobre a produção e comercialização da juçara nesta região. Nesta pesquisa foi possível obter uma estimativa de dados sobre o número e localização dos produtores, e da comercialização do açaí juçara nos diversos canais de distribuição. Os resultados gerais da pesquisa indicam que, no caso do produtor, foram detectadas deficiências no manejo e dificuldades com relação ao extrativismo do palmito.
The present study aimed to determine the chemical composition and biological activity of the esse... more The present study aimed to determine the chemical composition and biological activity of the essential oil obtained from Phyllogonium viride Brid. (Phyllogoniaceae, Bryophyta), whose samples were collected in southern Brazil. For the first time, the cytotoxic activity of the essential oil of P. viride in breast and colorectal tumor cells (MCF‐7 and HCT‐116) was evaluated, as well as the cytotoxic potential of this oil in non‐tumoral cells of human immortalized keratinocytes (HaCaT) via MTT assay. The compounds majorly found in P. viride essential oil were β‐bazzanene (20.30 %), β‐caryophyllene (17.06 %), β‐chamigrene (14.02), and germacrene B (11.72 %). Treatment with P. viride essential oil in the different tested cell lines did not induce any toxicity in most of the tested concentrations. These data contribute to generating new scientific information about this understudied plant species. Furthermore, the chemical characterization of the compounds present in the essential oil of P. viride can lead to greater elucidation of its biotechnological potential.
The Cunila angustifolia essential oil was obtained from fresh leaves by hydrodistillation and ana... more The Cunila angustifolia essential oil was obtained from fresh leaves by hydrodistillation and analyzed by GC‐FID and GC‐MS to determine its chemical composition. The essential oil presented pulegone (29.5 %) and isomenthol (27.0 %) as major components, and other compounds such as menthone (8.6 %), neomenthol (7.2 %), menthyl acetate (2.5 %) and caryophyllene oxide (2.0 %) were identified. The cytotoxic activity of the essential oil was evaluated by MTS assay, with the human cancer cell lines of the lung (A549), breast (MCF‐7) and skin melanoma (SK‐Mel‐28). The assay showed the highest selectivity, to MCF‐7 cell lines, with IC50 equal to 34.0 μg mL−1, low selectivity for SK‐Mel‐28 cell lines, with IC50 equal to 279.9 μg mL−1, and no mortality to A549 cell lines.
Raman spectroscopy is a rapid and non-destructive analytical technique that has found a growing i... more Raman spectroscopy is a rapid and non-destructive analytical technique that has found a growing interest in the characterization and quantification of microconstituents in foods. In this work, Raman spectroscopy was used to evaluate the carotenoids content of processed Bunchosia Glandulifera, a native fruit from the Brazilian Atlantic Forest. The B. glandulifera pulps were dried in hot air at 65 and 85 °C, resulting in carotenoids degradation of about 75 and 80%, respectively. The degradation profile of carotenoids over time was analyzed by Raman spectroscopy, with and without the use of an internal standard (TiO 2). The reproducibility of the analyses was evaluated by PCA of spectral data. PLS regression was applied for modelling the total carotenoids in B. glandulifera. Resulting models show the Raman data correlate with carotenoids content on samples resulting in a satisfactory coefficient of determination for all sets of samples.
The orange-fleshed sweet potato is a vegetable-rich in carotenoids. The thermic treatment for swe... more The orange-fleshed sweet potato is a vegetable-rich in carotenoids. The thermic treatment for sweet potato processing can decrease the content of these constituents in the foods, lowering their bioactive properties. Raman spectroscopy has been growing as a fast tool to food analysis, especially for detection of low concentrations of carotenoids and to the monitoring of its degradation profile over time. Therefore, in this work were evaluated two methods of drying, hot air and microwaving with rotary drum, combined with quantitative Raman spectroscopy. The results showed carotenoids degradation around 50 % for both types of drying processes studied. PCA plot proved the potential of reproducibility of analyses for microwave drying samples. For samples heated with hot air, the best linear correlation achieved was R 2 = 0.90 and by microwave was R 2 = 0.88. Also, partial least squares (PLS) regression models were constructed obtaining a satisfactory coefficient of determination.
Rapanea ferruginea antioxidant and antitumoral properties were not explored before in literature.... more Rapanea ferruginea antioxidant and antitumoral properties were not explored before in literature. This study aimed to investigate these biological activities for the R. ferruginea leaf extract and correlate them with its phenolic content and influence in biological membrane dynamics. Thus, in this study, anti/pro-oxidative properties of R. ferruginea leaf extract by in vitro DPPH and TBARS assays, with respect to the free radical reducing potential and to its activity regarding membrane free radical-induced peroxidation, respectively. Furthermore, preliminary tests related to the extract effect on in vitro glioma cell viability were also performed. In parallel, the phenolic content was detected by HPLC-DAD and included syringic and trans-cinnamic acids, quercetrin, catechin, quercetin, and gallic acid. In an attempt to correlate the biological activity of R. ferruginea extract and its effect on membrane dynamics, the molecular interaction between the extract and a liposomal model wi...
Optimization of electrochemical methods for total antioxidant capacity (TAC) determination of Bun... more Optimization of electrochemical methods for total antioxidant capacity (TAC) determination of Bunchosia glandulifera (Jacq.) Kunth (Malpighiaceae) extracts was performed. Other methods for antioxidant studies were also used for comparison with the results obtained by electrochemical assays. The extracts exhibited good solubility in the aprotic solvent dimethylsulfoxide. Hence, two electrochemical methods, namely cyclic (C) and differential pulse (DP) voltammetry (V) were optimized for TAC determination in this medium and by using ascorbic acid. The CV presented better linearity than DPV in the optimum conditions. TAC values determined by ABTS, FRAP and DPPH increased in the order seed < pulp < bark < leaf < root extract, in generally the same order observed by CV, indicating the applicability of the method in these conditions. The phenolic compounds contents were 302±10, 327±11, 1,008±71, 4,003±13 and 7,502±30 mg gallic acid/100 g extract, respectively, increasing in the same order as observed for TAC. On the other hand, such order disagreed with the amounts of major antioxidant vitamins, carotenoids and ascorbic acid, estimated in these extracts, which corresponded, by comparison with the contents of phenolic compounds, to 0.62, 34, 9.9, 0.39 and 0.86 %, respectively. Thus, it can be inferred that specially in the case of roots and leaves, the contents of phenolic compounds may have greater contribution for their TAC values.
Resumo O estudo do processo de secagem foi realizado a partir da utilização de técnicas de planej... more Resumo O estudo do processo de secagem foi realizado a partir da utilização de técnicas de planejamento experimental investigando os seguintes fatores temperatura de secagem (30 a 80 °C), massa da amora (6,0 a 135 g) e tempo (16 a 24 h), tendo como variável de resposta a umidade e concentração dos compostos fenólicos. Também foram fixados os fatores: tipo de amostra (triturada) e estufa (com circulação de ar) para realização dos ensaios experimentais. Os resultados mostraram perdas pequenas de compostos bioativos no processo a 55 °C por 16 horas com 80 g de amostra. De acordo com as análises químicas, a farinha encontra-se dentro dos padrões exigidos pela legislação brasileira para farinhas (máximo de 15%), podendo ser classificada como produto de alto percentual de fibra (24,33±2,88 g/100 g de farinha). Foram determinadas na farinha através de métodos espectrofotométricos: Fenólicos Totais: 344,94 mg GAE/100 g; Flavonoides Totais 182,82 mg Ce/100 g; Antocianinas Totais 77,93 mg/100...
An expedient, palladium-mediated cross-coupling approach to functionalize the benzimidazole-based... more An expedient, palladium-mediated cross-coupling approach to functionalize the benzimidazole-based core under microwave-assisted conditions has been developed and is described. This protocol, which incorporates appendage diversity on this potential scaffold, is found to be compatible with a wide range of electronicallyand sterically-divergent (hetero)aryl boronic acids. The use of the PdCl2/(SPhos) catalytic system allows the formation of a stable and highly active LPd(0) species which was found to be critical for the successful synthesis of these novel, pharmacologically-relevant molecules.
The maize weevil, Sitophilus zeamais is a major pest of stored grain whose control has been perfo... more The maize weevil, Sitophilus zeamais is a major pest of stored grain whose control has been performed with the use of synthetic insecticides, which in many cases are being banned due to issues involving risks to human and animal health and to the environment. In order to avoid the use of these insecticides, alternative control has been sought, including the use of plant extracts. In this study, “poejo”, Cunila angustifolia leaves extracts and essential oils have been used against S. zeamais. The results of the bioassay for the control of S. zeamais showed statistical significance (P <0.05) for all sources of variation. The essential oil reached 100% efficiency at all different concentrations, the hexane extract at 0.32% showed 38.70% efficiency, while the aqueous and crude extracts showed no insecticidal effect on adults of S. zeamais. The highest mortality rate was found after 96 h of application of the extracts.
A composição química do óleo volátil das folhas de três matrizes de D. frutescens, coletadas no p... more A composição química do óleo volátil das folhas de três matrizes de D. frutescens, coletadas no período de um ano foi determinada por cromatografia gasosa-espectrometria de massas (GC-MS) e cromatografia gasosa com detector de ionização de chama (GC-FID). Os óleos voláteis da espécie foram caracterizados predominantemente por norisoprenóides (β-damascenona, β-ionona e α-ionona), seguida da ocorrência de sesquiterpenos. Através da análise multivariada foi observado que os compostos β-damascenona e β-ionona influenciaram de forma intensa a composição dos óleos voláteis e que espécies coletadas na mesma cidade apresentaram composição química similar. The chemical composition of the volatile oil from the leaves of three specimens of D. frutescens, collected over a period of one year, was determined by gas chromatography-mass spectrometry (GC-MS) and gas chromatography with flame ionization detection (GC-FID). These essential oils were characterized by the presence of norisoprenoids (β-damascenone, β-ionone, and α-ionone), as well as sesquiterpenes. Multivariate analysis showed that the compounds β-damascenone and β-ionone exerted the greatest influence on spatial and temporal differences in the composition of the oils. Samples obtained from specimens located in the same city showed similar chemical compositions.
The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is... more The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is a large tree, and its wood is used as a reservoir for distilled spirits, especially Cachaça. In this pioneering work, the essential oil was extracted monthly from the leaves of M. frondosus, for a period of 1 year. The essential oil was extracted by using hydrodistillation and the determination of the chemical composition of essential oil was performed by using the chromatographic techniques GC-FID and GC-MS. Thirty-three compounds were identified in the essential oil and bicyclogermacrene was the major compound. Through multivariate analysis, it was determined that β-caryophyllene, limonene and terpinen-4-ol were directly proportional to climatic factors. The yield of the oil was directly proportional to temperature and radiation.
Foi avaliada a atividade antioxidante pelo Sistema β-caroteno/Ácido Linoleico, ensaio do radical ... more Foi avaliada a atividade antioxidante pelo Sistema β-caroteno/Ácido Linoleico, ensaio do radical DPPH• (2,2-difenil-1-picrilhidrazila), do extrato bruto (EB) e frações hexânica (FH), clorofórmica (FC) e acetato de etila (FA) das pimentas malagueta (C. frutescens), cambuci (C. baccatum var. pendulum), cumari (C. baccatum var praetermissum) e pimentão magali (C. annuum var. annuum). As concentrações de capsaicinoides e de fenólicos totais presentes nas pimentas também foram determinadas. Os resultados obtidos demonstraram que as FC e FA das pimentas apresentaram maior concentração de fenólicos totais e capsaicinoides, sendo que a pimenta cumari foi a espécie com maior concentração destes compostos. A melhor atividade antioxidante pelo Sistema β-caroteno/Ácido Linoleico, foi obtida para o EB e FA da pimenta cambuci, seguida do EB da pimenta malagueta. Pelo método DPPH a FC e FA apresentaram menores valores de EC50, sendo a pimenta cumari e cambuci as mais efetivas. Estes resultados dem...
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