Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add filters








Year range
1.
São Paulo; s.n; s.n; 2022. 103 p. tab, ilus, graf.
Thesis in Portuguese | LILACS | ID: biblio-1378523

ABSTRACT

O Brasil é o país que possui a maior diversidade de bambus em todo o continente americano, com mais de 200 espécies catalogadas. Devido à alta resistência e durabilidade, essas espécies são muito utilizadas na construção civil e confecção de móveis e utensílios. No entanto, faltam estudos que investiguem a composição química e as atividades biológicas. Neste projeto foram avaliados extratos etanólicos de folhas e colmos de Guadua chacoensis (Rojas) Londoño & P.M. Peterson e frações em hexano, clorofórmio, acetato de etila e n-butanol. Também se obteve o óleo volátil, mas com um rendimento extremamente baixo (0,00079%). As frações dos extratos apresentaram teores de compostos fenólicos variando entre 1,92 e 15,80 µg EAG/mg. Esses compostos mostraram-se mais abundantes nas amostras de colmos. Em relação ao teor de flavonoides, as folhas apresentaram maior quantidade, variando entre 0,39 e 1,18 µg EQ/mg contra 0,17 a 0,34 µg EQ/mg nos colmos. Investigou-se a atividade antimicrobiana dos extratos, frações e óleo volátil frente cinco microrganismos: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans e Aspergillus brasiliensis. As amostras demonstraram potencial inibitório moderado a bom contra S. aureus e C. albicans, porém fraca para as demais espécies. Testou-se a capacidade antioxidante frente o radical DPPH e os resultados indicaram atividade antioxidante significativa, especialmente as frações acetato e butanol de colmos. As folhas apresentaram EC50 variando entre 67,5 e 124,0 µg/mL e os colmos entre 40,2 e 124 µg/mL. A inibição da enzima tirosinase, que está associada à produção de melanina, também se mostrou boa a uma concentração de 1 mg/mL, com o extrato bruto de colmos apresentando 43% de inibição, seguido pelas frações acetato (36%) e n-butanol (38%) de folhas. As análises por CG-MS detectaram pelo menos 44 compostos diferentes no óleo volátil, com vários terpenos e sesquiterpenos, e com ß-ionona sendo o componente majoritário (8,75%). As amostras de colmos e folhas apontaram grande diversidade de compostos, cerca de 20 para cada fração, onde os ácidos graxos como ácido palmítico e linoleico e seus ésteres derivados foram os mais abundantes. A análise dos perfis cromatográficos por CCD e CLAE revelaram a presença de ácido p-cumárico nos colmos de G. chacoensis. Esse composto tem relevante atividade antioxidante e de inibição da tirosinase. Também foi possível identificar a quercetagetina-7-O-glicosídeo, uma flavona glicosilada, com propriedades anti-inflamatorias e antidiabéticas. Desta forma, constatou-se que G. chacoensis apresenta grande diversidade de metabólitos secundários com atividades biológicas relevantes, como atividade antioxidante e clareadora, abrindo caminho para investigações mais profundas de suas aplicações, especialmente no segmento de cosméticos e produtos naturais


Brazil is the country with the greatest diversity of bamboo in the entire American continent, with more than 200 species catalogued. Due to their high resistance and durability, they are widely used in home construction and manufacture of furniture and utensils. However, studies investigating chemical composition and biological activities are absent. In this project, ethanol extracts from leaves and stems of Guadua chacoensis (Rojas) Londoño & P.M. Peterson and fractions in hexane, chloroform, ethyl acetate and n-butanol were evaluated. Volatile oil was also obtained, but with an extremely low yield (0.00079%). The fractions of the extracts presented contents of phenolic compounds varying between 1.92 and 15.80 µg GAE/mg. These compounds were more abundant in culm samples. In relation to the flavonoid content, leaves showed a greater amount, varying between 0.39 and 1.18 µg QE/mg against 0.17 to 0.34 µg QE/mg in culms. The antimicrobial activity of extracts, fractions and volatile oil were investigated against five microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis. The samples showed moderate to good inhibitory potential against S. aureus and C. albicans, but weak for the other species. The antioxidant capacity was tested against the DPPH radical and the results indicated significant antioxidant activity, especially acetate and butanol culm fractions. The leaves presented EC50 varying between 67.5 and 124.0 µg/mL and culms between 40.2 and 124 µg/mL. The inhibition of the enzyme tyrosinase, which is associated with the production of melanin, was also shown to be good at a concentration of 1 mg/mL, with the raw culm extract showing 43% inhibition, followed by acetate (36%) and n-butanol (38%) fractions of leaves. CG-MS analysis detected at least 44 different compounds in volatile oil, with several terpenes and sesquiterpenes, and with ß-ionone being the major component (8.75%). Culm and leaf samples showed great diversity of compounds, about 20 for each fraction, where fatty acids such as palmitic and linoleic acid and their derivative esters were the most abundant. The analysis of the chromatographic profiles by TLC and HPLC revealed the presence of p-coumaric acid in culms of G. chacoensis. This compound has relevant antioxidant and tyrosinase inhibiting activity. It was also possible to identify quercetagetine-7-O-glucoside, a glycosylated flavone, with anti-inflammatory and anti-diabetic properties. Thus, it was found that G. chacoensis presents a great diversity of secondary metabolites with relevant biological activities, such as antioxidant and whitening activity, opening ways for deeper investigations of its applications, especially in the segment of cosmetics and natural products


Subject(s)
Aspergillus/metabolism , Plant Extracts/agonists , Bambusa/adverse effects , Poaceae/chemistry , Antioxidants/analysis , Oils, Volatile/analysis , Chromatography, High Pressure Liquid/instrumentation , Monophenol Monooxygenase/classification , 1-Butanol , Bambusa/chemistry
2.
Braz. arch. biol. technol ; 64: e21190730, 2021. tab, graf
Article in English | LILACS | ID: biblio-1285554

ABSTRACT

Abstract Pyroligneous acid (PA) was obtained by condensation of the vapors produced in the thermal decomposition of culms residues from Guadua angustifolia Kunth (G. angustifolia) cultivated in Colombia, with and without previous preservation treatment with borax salts. Chemical characterization by GC-MS showed that PA extracts has high content of phenolic compounds. Mequinol, isocreosol, 4-ethylphenol, 4-ethyl-2-methoxyphenol, 3,5-dimethoxy-4-hydroxytoluene and 2,6-dimethoxyphenol were the most abundant substances, identified. The total phenolic content (TPC) and DPPH free radical scavenging activity, were investigated. TPC showed a concentration of 1.959 mg GA g-1±0.010 and 3.844 mg GA g-1±0.027 to PAC and PAS samples. These samples also exhibited high DPPH activity of 70.975%±0.921 and, 16.667%±0.298, respectively. The chemical composition, TPC and DPPH results indicate that the PA extracts obtained from G. angustifolia may be used as a raw material in the food industry as natural preservative, in medicine as alternative to antibiotics and in agriculture as insect repellent and foliar fertilizer.


Subject(s)
Mass Spectrometry , Bambusa/chemistry , Chromatography, Gas , Acetic Acid , Antioxidants/chemistry
3.
Rev. bras. enferm ; 68(2): 206-213, Mar-Apr/2015.
Article in Portuguese | LILACS, BDENF | ID: lil-752508

ABSTRACT

RESUMO Objetivo: analisar a percepção dos enfermeiros gestores da atenção primária à saúde sobre o processo de enfermagem. Método: estudo qualitativo em que os dados foram coletados por meio de entrevistas e analisados a partir da Análise de Conteúdo proposta por Bardin. Resultados: os gestores reconhecem a importância do processo de enfermagem, embora sua implementação não seja prioridade no momento. Existe dificuldade conceitual e não compreensão de que a implementação da metodologia de assistência deva perpassar pela gestão municipal. Conclusão: necessita-se de ampliação da visão dos gestores quanto à importância do processo de enfermagem e qualificação dos profissionais. Acredita-se na participação ativa dos órgãos legisladores de enfermagem, gestão local de saúde e governo federal para que a implementação do processo de enfermagem seja viabilizada. .


RESUMEN Objetivo: analizar las percepciones de los gerentes de enfermería de atención primaria de salud en el proceso de enfermería. Métodos: estudio cualitativo; los datos fueron recolectados a través de entrevistas y analizados desde el Análisis de Contenido propuesta por Bardin referencial teórico. Resultados: los gerentes reconocen la importancia del proceso de enfermería, aunque su aplicación no es la prioridad en este momento. No hay ninguna dificultad conceptual y la comprensión de que la ejecución de la ayuda metodología debe impregnar la gestión municipal. Conclusión: es necesario ampliar la visión de los administradores en cuanto a la importancia del proceso y la calificación de enfermería. Cree en la participación activa de los órganos legislativos de enfermería, administración de salud local y el gobierno federal para la aplicación del proceso de enfermería es factible. .


ABSTRACT Objective: this qualitative study aimed to analyze the perceptions of primary health care management nurses on the nursing process. Method: data were collected through interviews and analyzed by the Content Analysis proposed by Bardin’s theoretical framework. Results: managers recognize the importance of the nursing process, although its implementation was not a priority at the time of the interviews. A conceptual diffi culty and a lack of understanding that the implementation of the care methodology should be a cross-departmental action in the local healthcare management were clearly observed. Conclusion: managers should have their perspectives broadened concerning the relevance of the nursing process and the professional training. The active participation of legislative nursing bodies, local healthcare management and the federal government may open the way for the effective implementation of the nursing process. .


Subject(s)
Bambusa/metabolism , Carbon Sequestration/physiology , Carbon/chemistry , Plant Leaves/chemistry , Soil/chemistry , Trees/metabolism , Bambusa/chemistry , China , Carbon/metabolism , Forests , Plant Leaves/metabolism , Seasons , Tropical Climate , Trees/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL