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Natural compounds produced by cyanobacteria have a large structural variety and several biotechnologic al applications, such as biofertilization, bioremediat ion, biofuels, food and feed. Some compounds have properties in antiviral, antibacterial, antifungal and anticancer activities. Aphano thece halophytica is a halotolerant cyanobacteria which can grow at a wide range of salt concentration and ph values. Due the adaptation strategies to live on these extreme envi ronments, they can be a rich source of bioactive co mpounds. The salt production in salines consists in the use of different water reservoirs, where natural water evaporation gradually increases salt concentration in each rese rvoir until salt precipitation. In this study, we c ollected Aphanothece halophytica strains at the crystallizer reservoir, where the s alinity was 225, at a saline in Cabo Frio, RJ. The cyanobacteria was identified by micro scopic analysis following Komarek and Anagnostidis (1988) method. Four extracts were obtained using so lvents with different polarities . The methanol extract was evaluated for antibacterial activity on micro assay s using P seudomonas sp ., Vibrio sp . and Pseudoalteromonas sp .. These bacteria are involved both in health and e nvironmental issues, due to their participation on some pathologies and on the formation of biofilms, one o f the first steps of biofouling. The extract affect ed the growth of some of the assayed bacteria with differe nt intensities, showing that it may have antibacter ial compounds. Other extractions methods and biological assays must be tested to elucidate which compounds are responsible for this activity and their mechanism o f action. These preliminary results corroborates th e biotechnological potential of cyanobacteria from hy persaline environments. The relatively low cost and fast grow of this organisms may facilitate furthers stud ies and commercial exploitation.

Caulerpina é um alcaloide bisindólico descrito como substância majoritária do gênero C au le rpa . Atualmente é alvo de grande interesse e tem sido destacada com o possível novo fármaco contra doenças inflamatória s e dor. Contudo, os métodos de extração da caulerpina e seus rendimentos variam na literatura o objetivo deste trabalho é comparar estes métodos. Para tanto, a al ga Caulerpa racemosa foi coletada, seca à temperatura ambiente e posteriormente submetida aos seguintes m étodos de extração: Maceração dinâmica (MA), Soxhle t (SX), assistida por Ultrassom (UL) e assistida por Micro-ondas (MO). Todos empregaram como solvente o metanol na proporção de 10 mL/g de alga seca. Os pa râmetros de comparação foram: tempo, temperatura, rendimento do extrato, presença e rendimento de cau lerpina. A confirmação da presença de caulerpina fo i verificada em todos os extratos por análise de Crom atografia em Camada Delgada (CCD) com placas de síl ica gel e por medidas de absorbância de espectros de UV . A banda mais intensa de caulerpina na CCD foi verificada na extração MO. Tal resultado foi corrob orado pela espectrofotometria UV. Os valores de absorbância dos característicos da caulerpina foram maiores no ext rato de MO, seguidos pelo SX, enquanto as amostras de MA e UL obtiveram valores semelhante s. O extrato que apresentou o maior rendimento de caulerpina foi o MO. O extrato SO apresentou rendim ento abaixo de MO e maior que MA e UL. O extrato UL, apesar de ter sido realizado em 21 minutos, tem po muito inferior à MA (72h), teve capacidade de ex tração semelhante. Assim, o método de extração assistida p or Micro-ondas foi o mais eficaz devido à maior intensidade da banda de caulerpina presente no CCD e nos maiores valores de absorbância no espectro em UV.

Marine invertebrates are source of molecules that have different ecological functions and unique complexity. Bioprospecting aims to identify the application of these molecules and their isolation. Among these applications, molecules with anticancer properties are subject to bioprospecting in natural products. The hypothesis is that the cytotoxic activity of these products is capable of inhibiting proliferation of glioblastoma, the most lethal cancer in central nervous system. Therefore, the present study aimed to evaluate the anticancer potential of crude extracts from six marine invertebrates at Arraial do Cabo, Rio de Janeiro, being: two exotic invasive species as Tubastraea coccinea and Didemnum sp.; two established exotic species as Darwinella sp. and Chromonephthea braziliensis; and two native species as Palythoa caribaeorum and Phyllogorgia dilatata. To produce de crude extracts from marine invertebrates, five different individuals were collected, fixed in ethanol 90% and triturated. Then homogenates were diluted in methanol (1:5) and evaporated using rotary evaporator for 4h at 50oC. To evaluate the anticancer evaluation, the cell viability of the T98G and U251 human glioblastoma cells and the healthy human cell fibroblast cell line was analyzed by the acid phosphatase method in both monolayer and three-dimensional cell culture models. The cells were cultured with 100, 200, 400, 800 e 1000microg/mL, and 12.5, 25, 50, 100 e 200microg/mL for Didemnum sp. Cell viability assays were analyzed by Kruskal-Wallis non-parametric statistical test followed by multiple comparisons to control by the Dunn's test. The values were expressed by the median and their distribution (min-max) and were considered significant when P ≤ 0.05. The anticancer evaluation, the crude extract from Didemnum sp. and T. coccinea were effective in both culture models (2D and 3D), showed selective citotoxic effect in both glioblastoma cell lines, without citotoxicity of human fibroblasts. The IC50 of the extracts was 120.6 and 432. 8 (microg /mL) for T98G cells and 63.32 and 317.2 (microg/mL) for U251 cells, of Didemnum sp. and T. coccinea, respectively. It is suggested that the exotic invasive species Didemnum sp. and T. coccinea it is found in abundance and its’ crude extracts promising for the development of biotechnological products with pharmaceutical applications. Future experiments as chemical profile will be performed to identify the active biocompounds in these crude extracts and to forward to in vivo scale for brain tumor therapeutic future approach.

Chagas' disease is a parasitic disease with unsatisfactory treatment, mainly in chronic stage. This study aimed to evaluate the trypanocidal activity and action mechanisms of α/β-amyrin and its semi-synthetic derivatives, together with four isolated natural triterpenes, tested against trypomastigote and amastigote forms. The structure-activity relationship was suggested and cytotoxicity was measured. In general, greater polar compounds may have improved the selectivity to the protozoan. Action mechanisms were only performed for the amastigotes of Trypanosoma cruzi by evaluating the ultrastructural alterations, membrane permeability, mitochondrial membrane potential and cell volume, since the majority of compounds displayed promising antiamastigote activities. Triterpenes promoted changes on mitochondrial membrane potential and ultrastructural features that suggest autophagy processes. Both combinations between α/β-amyrin and 3-O-acetyl-11-oxo-α/β-amyrin and 3-O-acetyl-α/β-amyrin with benznidazole displayed synergistic effects against amastigotes and antagonistic effects on LLCMK2 cells. The antiamastigote activities, chemical derivatization, drug combinations and action mechanisms revealed to be crucial approaches toward this chronic disease.

Texto completo: acesso restrito. p. 78–83 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2014-05-20T15:48:21Z No. of bitstreams: 1 1-s2.0-S0026265X12000926-main.pdf: 672034 bytes, checksum: 5da1fe5884b21dac691ffe6f65740c7e (MD5) Made available in DSpace on 2014-05-20T15:48:21Z (GMT). No. of bitstreams: 1 1-s2.0-S0026265X12000926-main.pdf: 672034 bytes, checksum: 5da1fe5884b21dac691ffe6f65740c7e (MD5) Previous issue date: 2013 N,N-dimethyltryptamine (DMT) is a psychoactive indole alkaloid present in beverages consumed in religious ceremonies and in neo-shamanic rituals all around the world. It is a substance banned in most countries, which makes its acquisition difficult. In Brazil, a beverage rich in DMT named ayahuasca is legally consumed in a religious context. On the other hand, DMT is a controlled drug, enforced by the Brazilian National Health Surveillance Agency (Agência Nacional de Vigilância Sanitária). The present study describes a simple and fast method to obtain N,N-dimethyltryptamine (DMT) from inner barks of Mimosa tenuiflora for the purpose of using it as a chromatographic analytical standard. Fourier transform infrared spectroscopy (FTIR), single and tandem stage mass spectrometry (MS), nuclear magnetic resonance spectroscopy (1H and 13C NMR) and melting point measurements were performed for the structural characterization of N,N-dimethyltryptamine. The results obtained were in agreement with previous literature reports. The purity of the compound (> 95%) was determined using ultraviolet (UV) absorption spectrometry with a tryptamine analytical standard.