26 research outputs found

    Purple corn (zea mays l.) pericarp hydroalcoholic extracts obtained by conventional processes at atmospheric pressure and by processes at high pressure

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    Extracts of Peruvian purple corn pericarp (Zea mays L.) were obtained: (1) via supercritical fluid extraction with CO2 as solvent and EtOH-H2O (70:30, v/v) as co-solvent, (2) via pressurized liquid extraction (PLE) with EtOH-H2O (70:30, v/v) and, (3) via two conventional extraction processes, stirred vessel and Soxhlet. The extraction yields and extract compositions were compared to each other. The parameters measured were the point-to-point extraction yield, the global extraction yield and composition of extracts regarding contents of total phenolics, total flavonoids, total anthocyanins and specific anthocyanins such as cyanidin-3-glucoside, peonidin-3-glucoside and pelargonidin-3-glucoside. Antioxidant activity by DPPH and in vitro antiproliferative activity were also evaluated considering seven cancer cell lines. High yields and higher contents of phenolic compounds, accompanied by a high antioxidant activity at 50 °C, were obtained for supercritical extraction at 60 °C. Antioxidant activity showed good correlation with the content of phenolic compounds, but there was no antiproliferative activity37237248COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informação12/51317-

    Furanoditerpenes from Pterodon pubescens benth with selective in vitro anticancer activity for prostate cell line

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    Activity guided fractionation of Pterodon pubescens Benth. methylene chloride-soluble fraction afforded novel 6α-acetoxi 7β-hydroxy-vouacapan 1 and four known diterpene furans 2, 3, 4, 5. The compounds were evaluated for in vitro cytotoxic activities against human normal cells and tumour cell lines UACC-62 (melanoma), MCF-7 (breast), NCI-H460 (lung, non-small cells), OVCAR-03 (ovarian), PC-3 (prostate), HT-29 (colon), 786-0 (renal), K562 (leukemia) and NCI-ADR/RES (ovarian expressing phenotype multiple drugs resistance). Results were expressed by three concentration dependent parameters GI50 (concentration that produces 50% growth inhibition), TGI (concentration that produces total growth inhibition or cytostatic effect) and LC50 (concentration that produces -50% growth, a cytotoxicity parameter). Also, in vitro cytotoxicity was evaluated against 3T3 cell line (mouse embryonic fibroblasts). Antiproliferative properties of compounds 1, 4 and 5 are herein reported for the first time. These compounds showed selectivity in a concentration-dependent way against human PC-3. Compound 1 demonstrated selectivity 26 fold more potent than the positive control, doxorubicin, for PC-3 (prostrate) cell line based on GI50 values, causing cytostatic effect (TGI value) at a concentration fifteen times less than positive control. Moreover comparison of 50% lethal concentration (LC50 value) with positive control (doxorubicin) suggested that compound 1 was less toxic

    Furanoditerpenes from Pterodon pubescens benth with selective in vitro anticancer activity for prostate cell line

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    Activity guided fractionation of Pterodon pubescens Benth. methylene chloride-soluble fraction afforded novel 6α-acetoxi 7β-hydroxy-vouacapan 1 and four known diterpene furans 2, 3, 4, 5. The compounds were evaluated for in vitro cytotoxic activities against human normal cells and tumour cell lines UACC-62 (melanoma), MCF-7 (breast), NCI-H460 (lung, non-small cells), OVCAR-03 (ovarian), PC-3 (prostate), HT-29 (colon), 786-0 (renal), K562 (leukemia) and NCI-ADR/RES (ovarian expressing phenotype multiple drugs resistance). Results were expressed by three concentration dependent parameters GI50 (concentration that produces 50% growth inhibition), TGI (concentration that produces total growth inhibition or cytostatic effect) and LC50 (concentration that produces -50% growth, a cytotoxicity parameter). Also, in vitro cytotoxicity was evaluated against 3T3 cell line (mouse embryonic fibroblasts). Antiproliferative properties of compounds 1, 4 and 5 are herein reported for the first time. These compounds showed selectivity in a concentration-dependent way against human PC-3. Compound 1 demonstrated selectivity 26 fold more potent than the positive control, doxorubicin, for PC-3 (prostrate) cell line based on GI50 values, causing cytostatic effect (TGI value) at a concentration fifteen times less than positive control. Moreover comparison of 50% lethal concentration (LC50 value) with positive control (doxorubicin) suggested that compound 1 was less toxic.O fracionamento biomonitorado do extrato diclorometĂąnico das sementes de Pterodon pubescens Benth forneceu o 6α-acetĂłxi-7β-hidrĂłxi-vouacapano 1 (inĂ©dito), alĂ©m de quatro diterpenos furĂąnicos (2, 3, 4 e 5). A atividade antiproliferativa dos compostos foi avaliada in vitro contra as linhagens de cĂ©lulas tumorais humanas UACC-62 (melanoma), MCF-7 (mama), NCI-H460 (pulmĂŁo), OVCAR-03 (ovĂĄrio), PC-3 (prĂłstata), HT-29 (colon), 786-0 (rim), K562 (leucemia) e NCI-ADR/RES (ovĂĄrio com fenĂłtipo de resistĂȘncia a mĂșltiplos fĂĄrmacos). Os resultados foram expressos em trĂȘs concentraçÔes efetivas GI50 (concentração para que ocorra 50% de inibição de crescimento), TGI (concentração que resulta em inibição total de crescimento) e LC50 (concentração que resulta em 50% de morte celular). A citotoxicidade in vitro foi avaliada tambĂ©m frente a uma linhagem de cĂ©lula murina normal (3T3). Este Ă© o primeiro relato de atividade anticĂąncer para os compostos 1, 4 e 5, que apresentaram grande seletividade, dependente da concentração, para PC-3. O composto 1 foi 26 vezes mais potente para inibir 50% do crescimento (GI50) de PC-3, 15 vezes mais citostĂĄtico (TGI) e 6 vezes menos tĂłxico (LC50) quando comparado com Doxorrubicina (controle).569575Fundação de Amparo Ă  Pesquisa do Estado de SĂŁo Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientĂ­fico e TecnolĂłgico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de NĂ­vel Superior (CAPES

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

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    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

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    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Fractionation of ethanolic and hydroalcoholic extracts of green propolis using supercritical carbon dioxide as an anti-solvent to obtain artepillin rich-extract

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    Green propolis from southeastern Brazil is known for its potent biological activity and the presence of Artepillin-C. In order to obtain extracts concentrated in phenolic and artepillin-C compounds, supercritical carbon dioxide (scCO2) was used as an anti-solvent to selectively fractionate ethanolic and hydroalcoholic extracts of green propolis by precipitation in four separators in series. The fractions were evaluated for the global yield of each fraction and for the yields and concentrations of total phenolics (TP), total flavonoids (TF), 3,5-diprenyl-4-hydroxycinnamic acid (Artepillin C) (DHCA), 4-hydroxycinnamic acid (p-coumaric acid) (HCA) and 4-methoxy-3,5,7-trihydroxyflavone (kaempferide) (MTHF) in the fractionated extracts, also evaluated was he antioxidant activity by DPPH. The scCO2 was effective as an anti-solvent to obtain extract fractions rich in Artepillin C and with high antioxidant activity138167173CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informação2012/51317-

    RECUPERAÇÃO DE SESQUITERPENOS DO ÓLEO-RESINA DE COPAÍBA A PARTIR DA DESTILAÇÃO MOLECULAR

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    Copaiba oil-resin has aromatic characteristics and pharmacological activities attributed to sesquiterpenes compounds. These purified compounds present application in perfume, pharmaceutical and cosmetic industries. Therefore, the objective of this work was to use molecular distillation to recover and purify sesquiterpenes of the copaiba oil-resin with purity high. The parameters evaporator temperature (TEV) from 45 to 100 ÂșC and feed flow rate (Q) between 15 and 30 ml min-1 were evaluated through design of experiments (22 with center points). The results showed that it was possible to recover sesquiterpenes with 98.12% purity in the distillate stream. Increased in TEV and reduction in Q were the effects observed experimentally and through the response surface. The best experimental condition was TEV of 100 °C and Q of 15 mL min-1. Collor differences were noticed between distillate streams (colorless) and residue (brown). These can be used as parameters for separation of sesquiterpenes and diterpenes. The molecular distillation proved to be an efficient processo to both recovery and purification of sesquiterpenes from the copaiba oil-resin
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