The variations in the chemical composition, and consequently, on the biological activity of the propolis, are associated with its type and geographic origin. Considering this fact, this study evaluated propolis extracts obtained by supercritical extraction (SCO2) and ethanolic extraction (EtOH), in eight samples of different types of propolis (red, green and brown), collected from different regions in Brazil. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH and ABTS), Artepillin C, p-coumaric acid and antimicrobial activity against two bacteria were determined for all extracts. For the EtOH extracts, the anti-proliferative activity regarding the cell lines of B16F10, were also evaluated. Amongst the samples evaluated, the red propolis from the Brazilian Northeast (states of Sergipe and Alagoas) showed the higher biological potential, as well as the larger content of antioxidant compounds. The best results were shown for the extracts obtained through the conventional extraction method (EtOH). However, the highest concentrations of Artepillin C and p-coumaric acid were identified in the extracts from SCO2, indicating a higher selectivity for the extraction of these compounds. It was verified that the composition and biological activity of the Brazilian propolis vary significantly, depending on the type of sample and geographical area of collection.
Propolis is a natural product with many demonstrated biological activities and propolis extract has been used in the food, pharmaceutical and cosmetics industries. Different works have showed the variations in the chemical composition, and consequently, on the biological activity of the propolis that are associated with its type and geographic origin. Due to this study evaluated propolis extracts obtained through supercritical extraction and ethanolic extraction (conventional) in three samples of different types of propolis (red, green and brown), collected from different regions in Brazil (state of Bahia). Analyses were performed to determine the humidity, water activity, the content of total ash, proteins, lipids and fiber in raw propolis samples. The content of phenolic compounds, flavonoids, in vitro antioxidant activity (DPPH), catechin, ferulic acid and luteolin and antimicrobial activity against two bacteria (Staphylococcus aureus and Escherichia coli) were determined for all extracts. For the green and red ethanolic extracts the anti-leishmanicidal potential was also evaluated. The physicochemical profiles showed agreement in relation to the literature. The results identified significant differences among the extracts (p>0.05), which are in conformity with their extraction method, as well as with type and botanical origin of the samples. The extraction with supercritical fluid was not efficient to obtain extracts with the highest contents of antioxidants compounds, when compared with the ethanolic extracts. The best results were shown for the extracts obtained through the conventional extraction method (ethanolic) indicating a higher selectivity for the extraction of antioxidants compounds. The red variety showed the largest biological potential, which included the content of antioxidants compounds. The results found in this study confirm the influence of the type of the raw material on the composition and characteristics of the extracts. The parameters analysis were important to characterize and evaluate the quality of the different Brazilian propolis extracts based on the increased use of propolis by the natural products industry.
Recebido em 11/9/09; aceito em 2/2/10; publicado na web em 18/6/10 CHEMISTRY AND PHARMACOLOGY OF ANTINEOPLASIC CHEMOTERAPEUTICAL DERIVATIVES FROM PLANTS. This review demonstrates the importance of plants as sources of molecules used in anticancer therapies. The approach is performed by relating the active molecules to their origins, details, mechanisms of action, structure-activity relationship and chemical characteristics of chemotherapeutical medicines. It was also described the development of anticancer agents from plants by the pharmaceutical industry and the difficulties to release these compounds as a trademark. These include the well known paclitaxel, docetaxel, vincristine, vinblastine, vinorelbine, vindesine, etoposide, teniposide, and other molecules that are undergoing clinical trials.Keywords: plant antineoplasics; chemotherapic; cancer. INTRODUÇÃOSubstâncias orgânicas originadas de fontes naturais há muito tempo são utilizadas no tratamento de inúmeras enfermidades no ser humano. Grande parte dos medicamentos encontrados no mercado é derivada direta ou indiretamente de vegetais, micro-organismos, organismos marinhos, vertebrados e invertebrados terrestres.1,2 Analisando os medicamentos disponibilizados no mercado entre 1981 e 2002, observa-se que 28% destes possuem princípios ativos isolados de produtos naturais ou semissintéticos, ao passo que 24% são sintéticos com grupos farmacofóricos baseados em estruturas de produtos naturais. Portanto, mais da metade dos novos medicamentos lançados no referido período são derivados de produtos naturais, mostrando que essa fonte é muito importante nos estudos de desenvolvimento de novos medicamentos. 1,3 Os vegetais representam as maiores fontes de substâncias ativas que podem ser usadas na terapêutica, devido à grande diversidade estrutural de metabólitos produzidos e, talvez, a fonte mais antiga de medicamentos para o homem. Na busca de novos medicamentos originados de plantas são envolvidos diversos conhecimentos que vão desde aspectos agronômicos, botânicos, químicos, farmacológicos e toxicológicos. 4 Metodologias recentes cada vez mais modernas de isolamento e identificação de compostos de fontes naturais têm propiciado aumento no número de novas estruturas químicas bioativas para inúmeras indicações terapêuticas. Paralelo a esse progresso, desenvolveram-se métodos de screening biológicos automatizados (High Throughput Screening -HTS) que permitem testar in vitro milhares de substân-cias frente a alvos biológicos específicos em curto espaço de tempo.De acordo com Newman, 3 medicamentos derivados de produtos naturais são capazes de tratar 87% das enfermidades humanas categorizadas, incluindo as indicadas como antibacterianas, anticoagulantes, antiparasitárias, imunossupresoras e anticancerígenas. Esta última classe de medicamentos teve 1/3 do mercado em 2002 representado apenas por dois grupos de quimioterápicos derivados de produtos naturais, sendo que os taxanos e derivados da camptotecina representam cerca de U$ 3 bilhões de dólares. 2,5,6A busca por me...
The aim of this study was to determine the best processing conditions to extract Brazilian green propolis using a supercritical extraction technology. For this purpose, the influence of different parameters was evaluated such as S/F (solvent mass in relation to solute mass), percentage of co-solvent (1 and 2% ethanol), temperature (40 and 50°C) and pressure (250, 350 and 400 bar) using supercritical carbon dioxide. The Global Yield Isotherms (GYIs) were obtained through the evaluation of the yield, and the chemical composition of the extracts was also obtained in relation to the total phenolic compounds, flavonoids, antioxidant activity and 3,5-diprenyl-4-hydroxicinnamic acid (Artepillin C) and acid 4-hydroxycinnamic (p-coumaric acid). The best results were identified at 50°C, 350 bar, 1% ethanol (co-solvent) and S/F of 110. These conditions, a content of 8.93±0.01 and 0.40±0.05 g/100 g of Artepillin C and p-coumaric acid, respectively, were identified indicating the efficiency of the extraction process. Despite of low yield of the process, the extracts obtained had high contents of relevant compounds, proving the viability of the process to obtain green propolis extracts with important biological applications due to the extracts composition.
Objective: To report the results of a workshop regarding asthma management programs and centers (AMPCs) in Brazil, so that they can be used as a tool for the improvement and advancement of current and future AMPCs. Methods: The workshop consisted of five presentations and the corresponding group discussions. The working groups discussed the following themes: implementation of asthma management strategies; human resources needed for AMPCs; financial resources needed for AMPCs; and operational maintenance of AMPCs. Results: The workshop involved 39 participants, from all regions of the country, representing associations of asthma patients (n = 3), universities (n = 7), and AMPCs (n = 29). We found a direct relationship between a lack of planning and the failure of AMPCs. Based on the experiences reported during the workshop, the common assumptions about AMPCs in Brazil were the importance of raising awareness of managers; greater community participation; interdependence between primary care and specialized care; awareness of regionalization; and use of medications available in the public health system. Conclusions: Brazil already has a core of experience in the area of asthma management programs. The implementation of strategies for the management of chronic respiratory disease and their incorporation into health care system protocols would seem to be a natural progression. However, there is minimal experience in this area. Joint efforts by individuals with expertise in AMPCs could promote the implementation of asthma management strategies, thus speeding the creation of treatment networks, which might have a multiplier effect, precluding the need for isolated centers to start from zero.
Objective: To evaluate the impact of the Programa de Controle da Asma e Rinite Alérgica em Feira de Santana (ProAR-FS, Program for the Control of Asthma and Allergic Rhinitis in Feira de Santana) on the frequency of hospitalizations for asthma in patients monitored at a referral center for one year. Methods: This was a historical control study involving 253 consecutive patients with asthma, ages ranging from 4 to 76 years. We compared the frequency of hospital admissions and visits to the emergency room (ER) in the 12 months prior to and after their admission to the ProAR-FS. During the program, patients received free treatment, including inhaled medications and education on asthma. Demographic and socioeconomic aspects were also assessed. Results: There was a significant reduction in the number of hospitalizations (465 vs. 21) and of visits to the ER (2,473 vs. 184) after their admission to ProAR-FS (p < 0.001 for both). Of the 253 patients who had been hospitalized and had had ER visits within the year prior to the admission to ProAR-FS, only 16 were hospitalized and 92 visited the ER during the follow-up year, representing a reduction of 94% and 64%, respectively. Conclusions: Implementing a referral center for the treatment of asthma and rhinitis in the Unified Health Care System, with the free distribution of inhaled corticosteroids and the support of an education program, is a highly effective strategy for the control of asthma.Keywords: Hospitalization; Asthma; Rhinitis; Health services; Public health. ResumoObjetivo: Avaliar o impacto do Programa de Controle da Asma e Rinite Alérgica em Feira de Santana (ProAR-FS) na frequência de hospitalizações por asma em pacientes acompanhados por um ano em um centro de referência. Métodos: Estudo de controle histórico de 253 pacientes com asma, entre 4 e 76 anos idade, e admitidos consecutivamente. Comparou-se a frequência de internações e de atendimentos em emergência nos doze meses anteriores e posteriores à sua inclusão no ProAR-FS. Durante o programa, os pacientes receberam atendimento gratuito, incluindo medicação inalatória e educação em asma. Os aspectos demográficos e socioeconômicos também foram avaliados. Resultados: Houve redução significativa no número de internações (463 vs. 21) e de atendimentos em emergência (2.473 vs. 184) após a matrícula no ProAR-FS (p < 0,001 para ambos). Dos 253 pacientes internados e atendidos na emergência no ano anterior à participação no ProAR-FS, apenas 16 foram novamente internados e 92 foram atendidos na emergência durante o ano de acompanhamento, correspondendo a uma redução de 94% e 64%, respectivamente. Conclusões: A implementação de um ambulatório de referência para o tratamento de asma e rinite no Sistema Público de Saúde, com o fornecimento de corticoide inalatório e o suporte de um programa de educação, é uma estratégia muito efetiva para o controle da asma.
Acute viral bronchiolitis in the first year of life is a risk factor for asthma in children with parental history of asthma.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.