ANÁLISE FITOQUÍMICA E EFEITO GASTROPROTETOR DO EXTRATO HEXÂNICO DE STEMODIA MARITIMA L.

Stemodia maritima L. é um arbusto pertencente à família Plantaginaceae, popularmente conhecido como “mastruz-bravo” ou “melosa”. O objetivo deste trabalho foi determinar o perfil fitoquímico do extrato hexânico das folhas de S. maritima (EHSm) e analisar sua atividade gastroprotetora. O EHSm foi obtido por maceração exaustiva e submetido à caracterização fitoquímica por cromatografia em camada delgada (CCD) e cromatografia gasosa acoplada a espectrometria de massas (CGMs). Para análise de gastroproteção, os animais foram pré-tratados com veículo (solução aquosa contendo Tween 20 a 1%), lansoprazol e EHSm (25, 50 e 100 mg/kg). A lesão gástrica foi induzida com a administração de etanol absoluto e após a indução, os estômagos foram dissecados para análise macroscópica, histopatológica e análise de estresse oxidativo, através da quantificação de óxido nítrico (NO) e glutationa reduzida (GSH) e de parâmetro inflamatório através da quantificação de mieloperoxidade (MPO). Na análise fitoquímica por CCD, foram encontrados flavonoides, triterpenos, esteroides, saponinas, proantocianidinas e leucoantocianidinas, mono e sesquiterpernos. Na análise por GCMs, foi encontrado majoritariamente o ácido linoleico. O pré-tratamento com EHSm reduziu de forma significativa o índice de lesão ulcerativa, quando comparado ao controle lesionado. EHSm foi capaz de aumentar as concentrações de NO e GSH e diminuir a concentração de MPO nos tecidos analisados. Estes dados indicam que o EHSm preservou a mucosa contra danos lesivos e elucidam o efeito gastroprotetor de S. maritima, com possíveis mecanismos relacionados às ações antioxidante e anti-inflamatória

Considerações botânicas e potencial biológico da espécie Croton heliotropiifolius Kunth (Euphobiaceae):: Uma revisão de literatura

A espécie Croton heliotropiifolius Kunth, popularmente conhecida como “velame”, “velaminho” e “velame-de-cheiro”, constitui um importante representante do gênero Croton e da Família Euphorbiaceae. Deste modo, esta revisão teve o objetivo de elucidar a distribuição geográfica, características morfológicas, valor etnomedicinal, composição fitoquímica e atividades biológicas da espécie. Para isto, foram realizadas consultas nas bases de dados Lilacs, Pubmed, Scielo e Science direct, no período de 2000 a 2021, onde foram analisados artigos nacionais e internacionais. Com esta consulta, foi possível constatar a distribuição neotropical da espécie, tendo no Brasil ocorrência predominante na vegetação da caatinga. morfologicamente, o C. heliotropiifolius apresenta-se como subarbusto a arbusto com até dois metros de altura. Quanto ao seu valor etnomedicinal, tem sido usado principalmente no alivio da dor, em problemas gástricos, intestinais e na inflamação. As atividades biológicas atribuídas a espécie estão relacionadas à capacidade de inibição da acetilcolinesterase, atividade antifúngica, antibacteriana, capacidade larvicida, inseticida e repelente, fundamentadas em sua composição química, que compreende diversos compostos biologicamente ativos. Contudo, apesar do uso e conhecimento da população acerca da espécie, muitas de suas atividades ainda não foram investigadas, motivando assim novos estudos. Desta forma, trabalhos como o nosso constituem ferramenta importante para o entendimento das potencialidades da espécie, desenvolvimento de novas pesquisas e uso deste recurso vegetal de forma mais direcionada e compatível com suas propriedades já reconhecidas, o que auxilia o planejamento de políticas públicas e a inserção da espécie no arsenal de plantas medicinas aplicadas à saúde

Phytochemical analysis and biological activity from clidemia capitellata leaves (melastomataceae)

This research determined the phytochemical profile and evaluated the photoprotective, antimicrobial and antioxidant activities in extracts of Clidemia capitellata leaves, obtained with hexane, ethyl acetate and methanol. The phytochemical profile was determined through thin layer chromatography; tannins, flavonoids and total phenolics were measured; the antimicrobial activity was determined by Minimum Inhibitory Concentration and Minimum Microbicide Concentration in bacteria Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis and Enterococcus faecalis; Escherichia coli, Serratia marcescens and Pseudomonas aeruginosa, Mycobacterium smegmatis, and the yeast Candida albicans. Antioxidant activity was evaluated through the methods of Reducing Power, DPPH sequestration and phosphomolybdenum. The C. capitellata leaves show flavonoids, tannins, triterpenes, steroids, anthraquinones and essential oils; tannins, flavonoids and total phenolics were extracted in greater amounts with methanol, however, the acetate extract stood out in relation to antimicrobial activity, and none of the extracts showed photoprotective activity within the values established by Brazilian legislation.   Word keys: secondary metabolites. antioxidant. antimicrobial.Esta investigación determinó el perfil fitoquímico y evaluó las actividades fotoprotectoras, antimicrobianas y antioxidantes en extractos de hojas de Clidemia capitellata, obtenidos con hexano, etilo y metanol. El perfil fitoquímico se determinó mediante cromatografía en capa fina; se midieron taninos, flavonoides y fenoles totales; la actividad antimicrobiana se determinó mediante Concentración Mínima Inhibidora y Concentración Mínima de Microbicida en bacterias Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis y Enterococcus faecalis; Escherichia coli, Serratia marcescens y Pseudomonas aeruginosa, Mycobacterium smegmatis y la levadura Candida albicans. La actividad antioxidante se evaluó mediante los métodos de Poder Reductor, secuestro de DPPH y fosfomolibdeno. Las hojas de C. capitellata presentan flavonoides, taninos, triterpenos, esteroides, antraquinonas y aceites esenciales; los taninos, flavonoides y fenoles totales se extrajeron en mayor cantidad con metanol, sin embargo, el extracto se destacó en relación a la actividad antimicrobiana, y ninguno de los extractos mostró actividad fotoprotectora dentro de los valores establecidos por la legislación brasileña. Palabras llaves: metabolitos secundarios. antioxidante. antimicrobiano.Esta pesquisa determinou o perfil fitoquímico e avaliou as atividades fotoprotetora, antimicrobiana e antioxidante de extratos de folhas de Clidemia capitellata, obtidos com hexano, acetato de etila e metanol. Cromatografia em camada delgada foi usada para identificação dos metabólitos; taninos, flavonóides e fenólicos totais foram medidos; a atividade antimicrobiana foi determinada pela Concentração Inibitória Mínima e Concentração Microbicida Mínima nas bactérias Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis e Enterococcus faecalis; Escherichia coli, Serratia marcescens e Pseudomonas aeruginosa, Mycobacterium smegmatis e a levedura Candida albicans. A atividade antioxidante foi avaliada através dos métodos de Poder Redutor, sequestro de DPPH e fosfomolibdênio. As folhas de C. capitellata apresentam flavonóides, taninos, triterpenos, esteróides, antraquinonas e óleos essenciais; taninos, flavonóides e fenólicos totais foram extraídos em maiores quantidades com metanol, porém, o extrato acetato se destacou em relação à atividade antimicrobiana, e nenhum dos extratos apresentou atividade fotoprotetora dentro dos valores estabelecidos pela legislação brasileira. Palavras-chave: metabólitos secundários. antioxidante. antimicrobiano

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Biological Evaluation of Arylsemicarbazone Derivatives as Potential Anticancer Agents

International audienceFourteen arylsemicarbazone derivatives were synthesized and evaluated in order to find agents with potential anticancer activity. Cytotoxic screening was performed against K562, HL-60, MOLT-4, HEp-2, NCI-H292, HT-29 and MCF-7 tumor cell lines. Compounds 3c and 4a were active against the tested cancer cell lines, being more cytotoxic for the HL-60 cell line with IC50 values of 13.08 μM and 11.38 μM, respectively. Regarding the protein kinase inhibition assay, 3c inhibited seven different kinases and 4a strongly inhibited the CK1δ/ε kinase. The studied kinases are involved in several cellular functions such as proliferation, migration, cell death and cell cycle progression. Additional analysis by flow cytometry revealed that 3c and 4a caused depolarization of the mitochondrial membrane, suggesting apoptosis mediated by the intrinsic pathway. Compound 3c induced arrest in G1 phase of the cell cycle on HL-60 cells, and in the annexin V assay approximately 50% of cells were in apoptosis at the highest concentration tested (26 μM). Compound 4a inhibited cell cycle by accumulation of abnormal postmitotic cells at G1 phase and induced DNA fragmentation at the highest concentration (22 μM)