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Id: biblio-1290644
Autor: Feitosa, André de O; Dias, Amanda Cristina S; Ramos, Gisele da C; Bitencourt, Heriberto R; Siqueira, José Edson S; Marinho, Patrícia Santana B; Barison, Andersson; Ocampos, Fernanda M. M; Marinho, Adrey Moacir do R.
Título: Letalidad de citocalasina B y otros compuestos aislados del hongo Aspergillus spp. (Trichocomaceae) endófito de Bauhinia guianensis (Fabaceae) / Lethality of cytochalasin B and other compounds isolated from fungus Aspergillus sp. (Trichocomaceae) endophyte of Bauhinia guianensis (Fabaceae)
Fonte: Rev. argent. microbiol;48(3):259-263, set. 2016. ilus..
Idioma: en.
Resumo: Los hongos endofíticos son hongos que colonizan los tejidos internos de las plantas; varios compuestos biológicamente activos se han aislado a partir de estos hongos. Existen pocos estudios de compuestos aislados de hongos endófitos de plantas amazónicas. Por lo tanto, este estudio tuvo como objetivo el aislamiento y la identificación estructural de ergosterol (1), peróxido de ergosterol (2), mevalonolactona (3), citocalasina B (4) y citocalasina H (5) a partir de Aspergillus spp. EJC 04, un hongo endofítico de Bauhinia guianensis. La citocalasina B (4) y el derivado diacetato de citocalasina B (4a) mostraron una alta letalidad en el ensayo de Artemia salina. Esta es la primera aparición de citocalasinas en hongos endófitos amazónica de B. guianensis

Endophytic fungi are fungi that colonize internal tissues of plants; several biologically active compounds have been isolated from these fungi. There are few studies of compounds isolated from endophytic fungi of Amazon plants. Thus, this study aimed the isolation and structural identification of ergosterol (1), ergosterol peroxide (2), mevalonolactone (3), cytochalasin B (4) and cytochalasin H (5) from Aspergillus sp. EJC 04, an endophytic fungus from Bauhinia guianensis. The cytochalasin B (4) and the diacetate derivative of cytochalasin B (4a) showed high lethality in the brine shrimp assay. This is the first occurrence of cytochalasins in Amazonian endophytic fungi from B. guianensis
Descritores: Artemia/efeitos dos fármacos
Aspergillus/imunologia
Citocalasina B/isolamento & purificação
Citocalasina B/análise
Citocalasinas/isolamento & purificação
Bauhinia/microbiologia
Ergosterol/isolamento & purificação
Endófitos/patogenicidade
Tipo de Publ: Estudo de Avaliação
Estudo Observacional
Responsável: AR635.1 - FCVyS - Servicio de Información y Documentación


  2 / 97 LILACS  
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Id: biblio-1249211
Autor: Mohammed, AeshahMhana; Al-Ani, Laith Khalil Tawfeeq.
Título: Identification and Production of Beauvericin by Fusarium subglutinansand F. sacchari from Sugarcane
Fonte: Braz. arch. biol. technol;64:e21200088, 2021. tab, graf.
Idioma: en.
Resumo: Abstract Fusarium is producing several important mycotoxins including beauvericin (BEA). Two species of Fusarium viz. F. subglutinans and F. sacchari cause the Pokkahboeng disease of sugarcane. The studies on the occurrence and toxicity of BEA are scarce. Therefore, this study aimed to identify the isolates of Fusarium and detect their ability to produce BEA. The toxicity of BEA was also tested on brine shrimp Artemia salina. Many isolates of Fusarium were isolated from the infected plants of sugarcane in Malaysia. We identified the species of Fusarium according to their morphological characteristics. The capability of Fusarium isolates for producing the BEA was estimated by using a thin layer chromatography. The toxicity bioassay of BEA was conducted on the brine shrimp larvae. The results were identified on F. subglutinans and F. sacchari in 55 isolates of Fusarium. All isolates demonstrated the ability to produce BEA. Interestingly, BEA exhibited variation in toxicity between low toxic to very higher toxicity 100%. F. subglutinans and F. sacchari were able to produce BEA and possibly BEA may be causing toxicity in the host tissue and may be acting as a potential pathogenicity factor. Therefore, we consider BEA as an interesting factor in determining the virulence of fusarium isolate.
Descritores: Artemia
Depsipeptídeos
Fusarium
Micotoxinas
Responsável: BR1.1 - BIREME


  3 / 97 LILACS  
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Id: biblio-950732
Autor: Kabir, Md Golam; Rahman, Md Monsor; Ahmed, Nazim Uddin; Fakruddin, Md; Islam, Saiful; Mazumdar, Reaz Mohammad.
Título: Antioxidant, antimicrobial, toxicity and analgesic properties of ethanol extract of Solena amplexicaulis root
Fonte: Biol. Res;47:1-12, 2014. graf, tab.
Idioma: en.
Resumo: BACKGROUND: This study was subjected to investigate different pharmacological properties of ethanol extract ofSolena amplexicaulis root. RESULTS: The extract contains flavonoid, alkaloid, saponin and steroid compounds. The extract exhibited excellent antioxidant activity in DPPH radical scavenging activity. The extract also showed potent activity in brine shrimp lethality bioassay. The LC50 value was found to 44.677 µg/ml. The extract showed better anti-bacterial activity against gram-negative bacteria. In antifungal assay, the maximum 79.31% of anti-mycotic activity was observed against Aspergillus ochraceus while minimum 44.2% against Rhizopus oryzae. MIC value ranged between 1500 - 3000 µg/ml. The extract was found moderately toxic with a 24-hr LD50 value of 81.47 mg/kg in Swiss albino mice. The degree of inhibition by the ethanolic extract of the root was found less than that of standard analgesic drug diclofenac sodium. The extract also showed moderate anti-inflammatory and antinociceptive activity and anti-diabetic property. Reducing power of the extract was comparable with standard ascorbic acid. Moderate in vitro thrombolytic activity, lipid peroxidation inhibition property, metal chelating ability and stress-protective activity was also observed. CONCLUSION: Ethanol extract of Solena amplexicaulis root can be valuable for treatment of different diseases.
Descritores: Extratos Vegetais/farmacologia
Sequestradores de Radicais Livres/farmacologia
Raízes de Plantas/química
Cucurbitaceae/química
Analgésicos/farmacologia
Anti-Infecciosos/farmacologia
-Artemia/efeitos dos fármacos
Aspergillus/efeitos dos fármacos
Saccharomyces cerevisiae/efeitos dos fármacos
Shigella/efeitos dos fármacos
Bacillus/efeitos dos fármacos
Extratos Vegetais/química
Peroxidação de Lipídeos/efeitos dos fármacos
Testes de Sensibilidade Microbiana
Quelantes/farmacologia
Substâncias Redutoras/farmacologia
Fibrinolíticos/farmacologia
Hipoglicemiantes/farmacologia
Dose Letal Mediana
Anti-Inflamatórios/farmacologia
Antibacterianos/farmacologia
Antifúngicos/farmacologia
Antioxidantes/farmacologia
Limites: Animais
Camundongos
Responsável: CL1.1 - Biblioteca Central


  4 / 97 LILACS  
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Id: biblio-950741
Autor: Hossain, Mohammad Mobarak; Ahamed, Sayed Koushik; Dewan, Syed Masudur Rahman; Hassan, Md Mahadi; Istiaq, Arif; Islam, Mohammad Safiqul; Moghal, Md Mizanur Rahman.
Título: In vivo antipyretic, antiemetic, in vitro membrane stabilization, antimicrobial, and cytotoxic activities of different extracts from Spilanthes paniculata leaves
Fonte: Biol. Res;47:1-9, 2014. graf, tab.
Idioma: en.
Resumo: BACKGROUND: The study was conducted to evaluate the in vitro antimicrobial activity, cytotoxic, and membrane stabilization activities, and in vivo antiemetic and antipyretic potentials of ethanolic extract, n-hexane and ethyl acetate soluble fractions of Spilanthes paniculata leaves for the first time widely used in the traditional treatments in Bangladesh. RESULTS: In antipyretic activity assay, a significant reduction (P < 0.05) was observed in the temperature in the mice tested. At dose 400 mg/kg-body weight, the n-hexane soluble fraction showed the effect (36.7 ± 0.63°C ) as like as the standard (dose 150 mg/kg-body weight) after 5 h of administration. Extracts showed significant (P < 0.001) potential when tested for the antiemetic activity compared to the standard, metoclopramide. At dose 50 mg/kg-body weight, the standard showed 67.23% inhibition, whereas n-hexane and ethyl acetate soluble fractions showed 37.53% and 24.93% inhibition of emesis respectively at dose 400 mg/kg-body weight. In antimicrobial activity assay, the n-hexane soluble fraction (400 µg/disc) showed salient activity against the tested organisms. It exerts highest activity against Salmonella typhi (16.9 mm zone of inhibition); besides, crude, and ethyl acetate extracts showed resistance to Bacillus cereus and Bacillus subtilis, and Vibrio cholera respectively. All the extracts were tested for lysis of the erythrocytes. At the concentration of 1mg/ml, ethanol extract, and n-hexane and ethyl acetate soluble fractions significantly inhibited hypotonic solution induced lysis of the human red blood cell (HRBC) (27.406 ± 3.57, 46.034 ± 3.251, and 30.72 ± 5.679% respectively); where standard drug acetylsalicylic acid (concentration 0.1 mg/ml) showed 77.276 ± 0.321% inhibition. In case of heat induced HRBC hemolysis, the plant extracts also showed significant activity (34.21 ± 4.72, 21.81 ± 3.08, and 27.62 ± 8.79% inhibition respectively). In the brine shrimp lethality bioassay, the n-hexane fraction showed potent (LC50 value 48.978 µg/ml) activity, whereas ethyl acetate fraction showed mild (LC50 value 216.77 µg/ml) cytotoxic activity. CONCLUSIONS: Our results showed that the n-hexane extract has better effects than the other in all trials. In the context, it can be said that the leaves of S. paniculata possess remarkable pharmacological effects, and justify its folkloric use as antimicrobial, antipyretic, anti-inflammatory, and antiemetic agent. Therefore, further research may be suggested to find possible mode of action of the plant part.
Descritores: Asteraceae/química
Citotoxinas/farmacologia
Membrana Eritrocítica/efeitos dos fármacos
Antipiréticos/farmacologia
Antibacterianos/farmacologia
Antieméticos/farmacologia
-Artemia/efeitos dos fármacos
Salmonella typhi/efeitos dos fármacos
Staphylococcus aureus/efeitos dos fármacos
Bacillus cereus/efeitos dos fármacos
Bacillus subtilis/efeitos dos fármacos
Vibrio cholerae/efeitos dos fármacos
Bioensaio/mortalidade
Extratos Vegetais/farmacologia
Testes de Sensibilidade Microbiana
Galinhas
Folhas de Planta/química
Asteraceae/classificação
Etanol
Membrana Eritrocítica/fisiologia
Escherichia coli/efeitos dos fármacos
Testes de Sensibilidade a Antimicrobianos por Disco-Difusão
Temperatura Alta
Hexanos
Medicina Tradicional
Acetatos
Limites: Humanos
Animais
Camundongos
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950753
Autor: Zeb, Anwar; Sadiq, Abdul; Ullah, Farhat; Ahmad, Sajjad; Ayaz, Muhammad.
Título: Phytochemical and toxicological investigations of crude methanolic extracts, subsequent fractions and crude saponins of Isodon rugosus
Fonte: Biol. Res;47:1-6, 2014. tab.
Idioma: en.
Resumo: BACKGROUND: Isodon rugosus is used traditionally in the management of hypertension, rheumatism, tooth-ache and pyrexia. Present study was arranged to investigate I. rugosus for phytoconstituents, phytotoxic and cytotoxic activities to explore its toxicological, pharmacological potentials and to rationalize its ethnomedicinal uses. Briefly, qualitative phytochemical analysis of the plant extracts were carried out for the existence of alkaloids, flavonoids, saponins, oils, glycosides, anthraquinones, terpenoids, sterols and tannins. Plant crude methanolic extract (Ir.Cr), its subsequent fractions; n-hexane (Ir.Hex), chloroform (Ir.Chf), ethyl acetate (Ir.EtAc), aqueous (Ir.Aq) and saponins (Ir.Sp) in different concentrations were tested for phytotoxic and cytotoxic activities using radish seeds and brine shrimps (Artemia salina) respectively. The phytotoxic activity was determined by percent root length inhibition (RLI) and percent seeds germination inhibition (SGI) while the cytotoxicity was obtained with percent lethality of the brine shrimps. RESULTS: Ir.Cr was tested positive for the presence of alkaloids, glycosides, flavonoids, oils, terpenoids, saponins, tannins and anthraquinones. Among different fractions Ir.Sp, Ir.Chf, Ir.EtAc, and Ir.Cr were most effective causing 93.55, 89.32, 81.32 and 58.68% inhibition of seeds in phytotoxicity assay, with IC50 values of 0.1, 0.1, 0.1 and 52 µg/ml respectively. Similarly, among all the tested samples, Ir.Sp exhibited the highest phytotoxic effect causing 91.33% root length inhibition with IC50 of 0.1 µg/ml. Ir.Sp and Ir.Chf were most effective against brine shrimps showing 92.23 and 76.67% lethality with LC50 values of 10 and 12 µg/ml respectively. CONCLUSIONS: It may be inferred from the current investigations that I. rugosus contains different secondary metabolites and is a potential source for the isolation of natural anticancer and herbicidal drug molecules. Different fractions exhibited phytotoxic and cytotoxic activities, thus providing pharmacological basis for ethnomedicinal uses of this plant.
Descritores: Saponinas/análise
Extratos Vegetais/farmacologia
Isodon/química
Fitoterapia
-Artemia/efeitos dos fármacos
Taninos/análise
Terpenos/análise
Flavonoides/análise
Óleos Vegetais/análise
Clorofórmio
Antraquinonas/análise
Raízes de Plantas/crescimento & desenvolvimento
Citotoxinas
Componentes Aéreos da Planta/química
Metanol
Alcaloides/análise
Glicosídeos/análise
Hexanos
Limites: Animais
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950761
Autor: Shah, Syed Muhammad Mukarram; Sadiq, Abdul; Shah, Syed Muhammad Hassan; Khan, Shahzeb.
Título: Extraction of saponins and toxicological profile of Teucrium stocksianum boiss extracts collected from District Swat, Pakistan
Fonte: Biol. Res;47:1-5, 2014. tab.
Idioma: en.
Resumo: BACKGROUND: The current era is facing challenges in the management of neoplasia and weeds control. The currently available anti-cancer and herbicidal drugs are associated with some serious side effects. Therefore numerous researchers are trying to discover and develop plant based alternative particularly for the rational management of cancer and weed control. Teucrium stocksianum possess antioxidant and analgesic activities. The current study was designed to evaluate crude saponins (CS), methanolic extract and sub-fractions of T. stocksianum for cytotoxic and phytotoxic potentials. CS, methanolic extract and sub-fractions were extracted from powdered plant material using different solvents. Cytotoxic potential of the extracts at a dose of 10, 100 and 1000 µg/ml were evaluated against Brine shrimp's nauplii. Phytotoxic assay also performed at the same concentration against Lemna minor. Etoposide and Paraquat were used as positive controls in cytotoxic and phytotoxic assays respectively. RESULTS: The percent yield of crude saponins was (5%). CS demonstrated tremendous brine shrimp lethality showing < 10 µg/ml LC50. The n-hexane (HF) and chloroform fractions (CF) demonstrated excellent cytotoxicity with 80 and 55 µg/ml LC50 respectively. Whereas the methanolic extract (TSME), ethyl acetate (EAF) and aqueous fractions (AF) revealed moderate cytotoxicity showing 620, 860 and 1000 µg/ml LC50 values respectively. In phytotoxic assay profound inhibition was displayed by HF (96.67%) and TSME (95.56%, 30 µg/ml LC50) against the growth of Lemna minor at 1000 µg/ml respectively. Both CF and EAF demonstrated profound phytoxicity (93.33%) respectively at highest concentration (1000 µg/ml), while AF and CS demonstrated weak phytotoxicity with 1350 and 710 µg/ml LC50 values respectively. CONCLUSION: Cytotoxicity and phytotoxicity assays indicated that the crude saponins, n-hexane and chloroform fractions of T. stocksianum could play a vital role in the treatment of neoplasia and as potential natural herbicides. Therefore these sub-fractions are recommended for further investigation with the aim to isolate novel anti-cancer and herbicidal compounds.
Descritores: Saponinas/análise
Extratos Vegetais/química
Citotoxinas/farmacologia
Teucrium/química
-Paquistão
Artemia/efeitos dos fármacos
Saponinas/toxicidade
Extratos Vegetais/toxicidade
Araceae/classificação
Araceae/efeitos dos fármacos
Citotoxinas/análise
Teucrium/classificação
Teucrium/toxicidade
Metanol
Hexanos
Dose Letal Mediana
Medicina Tradicional/métodos
Limites: Animais
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


  7 / 97 LILACS  
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Id: lil-735015 LILACS-Express
Autor: Gallego Serna, Lina María; Torres Osorio, Javier Ignacio; Castañeda Salazar, Jorge Abel.
Título: Análisis dimensional del riesgo percibido por la exposición del público a radiaciones electromagnéticas emitidas por estaciones base de telefonía móvil / Dimensioal analyysis of risk perceived because of public exposure to electromagnetic radiations emitted by mobile phone base stations
Fonte: Rev. luna azul;(39):105-123, jul.-dic. 2014. ilus, tab.
Idioma: es.
Resumo: La omnipresencia de estaciones base de telefonía móvil (EBTM) en los territorios urbanos ha dado lugar a que la población esté siendo expuesta a las radiaciones no ionizantes (RNI) emitidas por este tipo de fuentes radioeléctricas, dado que estas han sido ubicadas cerca de los sitios donde habitan y/o concurren las personas que se han considerado más susceptibles a las radiaciones electromagnéticas. Este escenario se ha caracterizado por las constantes preocupaciones de los ciudadanos y expertos en torno a los posibles efectos nocivos que se pueden presentar por la exposición a las RNI; no obstante, existe también un ambiente de desconocimiento e incertidumbre frente al tema, lo que ha generado que sea más complejo evaluar este potencial riesgo de origen antrópico tecnológico. Por lo tanto, se consideró importante analizar la respuesta social frente al riesgo generado por las radiaciones electromagnéticas emitidas por EBTM, con el fin de realizar un diagnóstico integral de esta situación. Para ello, se adaptó el método del paradigma psicométrico, y se realizó un análisis descriptivo y multivariado, los cuales permitieron conocer la percepción social frente al riesgo en la zona que se consideró más crítica, según los resultados que surgieron del diagnóstico de las áreas urbanas expuestas a las RNI emitidas por las EBTM, localizadas en el municipio de Cartago (Valle del Cauca). Los resultados de los análisis muestran que la percepción de cada individuo se basa en juicios intuitivos y factores socioculturales, que se traducen en actitudes y decisiones que se toman frente al riesgo evaluado, que al parecer, en el imaginario social no ha sido concebido en su totalidad como un potencial factor de riesgo. Es por esto que se puede concluir que los juicios sobre el riesgo evaluado difieren no solo individualmente sino también colectivamente.

The omnipresence of mobile phone base stations (MPBS) in urban areas has resulted in the population being exposed to non-ionizing radiation (NIR) emitted by this type of radio sources, inasmuch as they have been located near places inhabited or frequently visited by people who are considered more susceptible to electromagnetic radiations. This scenario has been characterized by the constant concerns of citizens and experts about the possible adverse health effects that may occur from exposure to NIR. However, there is also an atmosphere of ignorance and uncertainty regarding the topic which makes it more difficult to evaluate this technological anthropogenic potential risk.. Therefore, it was considered important to analyze the social response in front of the risk generated by the electromagnetic radiation emitted by MPBS, in order to make an integral diagnosis of this situation. To do this, the psychometric paradigm method was adapted and a descriptive and multivariate analysis was carried out, which allowed knowing the social perception of the risk in the area that was considered more critical according to the results that emerged from the diagnosis of urban areas exposed to NIR emitted by MPBS located in the municipality of Cartago (Valle del Cauca). The results of the analyses show that the perception of each individual is based on intuitive judgments and sociocultural factors which result in attitudes and decisions made against the assessed risk which, apparently, in the social imaginary has not been conceived in its entirety as a potential risk factor. That is why, it can be concluded that judgments about the assessed risk differ not only individually but also collectively.
Descritores: Pesqueiros
-Artemia
Oceano Pacífico
Colômbia
Limites: Humanos
Tipo de Publ: Artigo Clássico
Responsável: CO54.1 - Centro de Biblioteca e Información Científica


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Morais, Selene Maia de
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Id: biblio-1132206
Autor: Nogueira Sobrinho, Antonio Carlos; Morais, Selene Maia de; Souza, Elnatan Bezerra de; Albuquerque, Maria Rose Jane Ribeiro; Santos, Hélcio Silva dos; Cavalcante, Carolina Sidrim de Paula; Sousa, Halisson Araújo de; Fontenelle, Raquel Oliveira dos Santos.
Título: Antifungal and Antioxidant Activities of Vernonia Chalybaea Mart. ex DC. Essential Oil and their Major Constituent β -caryophyllene
Fonte: Braz. arch. biol. technol;63:e20190177, 2020. tab, graf.
Idioma: en.
Projeto: FUNCAP-CE.
Resumo: Abstract: This article describes the chemical composition of Vernonia chalybaea essential oil, and investigates its antimicrobial, antioxidant and hemolytic activities. The evaluation of the antifungal activity was performed by the broth microdilution method using strains of yeasts and dermatophytic fungi. The checkerboard technique to find antimicrobial modulatory effects was performed using ketoconazole as standard drug. The antioxidant activity was evaluated by DPPH scavenging assay and β-carotene/linoleic-acid system. The toxicity was characterized by the brine shrimp lethality test and hemolysis bioassays. The essential oil was obtained by hydrodistillation and analyzed by GC-MS method, showing to be rich in the sesquiterpenes β-caryophyllene (39.06%) and bicyclogermacrene (19.69%), and also demonstrated a relevant antifungal activity against strains of Trichophyton rubrum. In the modulatory activity assay, the essential oil of V. chalybaea and β-caryophyllene demonstrated a synergistic interaction with ketoconazole, with increasing of its antifungal action. The antioxidant activity was evidenced mainly by β-carotene/linoleic acid system, with IC50 value of 35.87 ± 0.32 µg/mL. The results suggest that V. chalybaea essential oil and β-caryophyllene are valuable natural medicinal agents with antioxidant and antimicrobial activities.
Descritores: Óleos Voláteis/farmacologia
Vernonia/química
Cetoconazol/farmacologia
Antifúngicos/farmacologia
-Artemia
Bactérias/efeitos dos fármacos
Óleos Voláteis/química
Ácido Linoleico/farmacologia
beta Carioferinas/farmacologia
Fungos/classificação
Fungos/efeitos dos fármacos
Antibacterianos/farmacologia
Antifúngicos/química
Antioxidantes/farmacologia
Limites: Humanos
Animais
Responsável: BR1.1 - BIREME


  9 / 97 LILACS  
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Id: biblio-950822
Autor: Aftab, Usman; Zechel, David L; Sajid, Imran.
Título: Antitumor compounds from Streptomyces sp. KML-2, isolated from Khewra salt mines, Pakistan
Fonte: Biol. Res;48:1-10, 2015. ilus, graf, tab.
Idioma: en.
Resumo: BACKGROUND: Actinomycetes are gram positive bacteria with high G + C content in their DNA and are capable of producing variety of secondary metabolites. Many of these metabolites possess different biological activities and have the potential to be developed as therapeutic agents. The aim of the present study was to screen actinomycetes inhabiting halophilic environment such as Khewra salt mines present in Pakistan for cytotoxic and antitumor compounds. RESULTS: An actiomycetes strain designated as Streptomyces sp. KML-2 was isolated from a saline soil of Khewra salt mines, Pakistan. The strain Streptomyces sp. KML-2 showed 84 % cytotoxic activity against larvae of Artemiasalina. In the screening phase, the strain exhibited significant antitumor activity with IC50 values of 12, 48 and 56 µg/ml against Hela, MDBK and Vero cell lines, respectively. After that extract from 20 l fermentation was used to purify secondary metabolites by several chromatographic techniques. Structure elucidation of isolated compounds revealed that it is highly stable producer of Chromomycin SA (1) and 1-(1H-indol-3-yl)-propane-1,2,3-triol (2). Both of the isolated compounds showed significant antitumor activity against Hela and MCF-7 cancer cell lines (IC50 values 8.9 and 7.8 µg/ml against Hela; 12.6 and 0.97 µg/ml against MCF-7, respectively). The 16S rRNA gene sequence (1437 bp) of the strain confirm its identity (99 %) with Streptomyces griseus. CONCLUSIONS: From this research work we were successful in isolating two potent antitumor compounds, Chromomycin SA and 1-(1H-indol-3-yl)-propane-1,2,3-triol from Streptomyces KML-2 strain, isolated from Khewra salt mine. As such this is the second report which confirms that S. griseus can produce Chromomycin SA without introducing any mutagenesis in its biosynthesizing gene cluster and isolated indole derivative is being reported first time from any member of actinomycetes group with having novel antitumor activity against Hela and MCF-7 cells Nucleotide sequences: Nucleotide sequence data reported are available in the GenBank database under the accession number: GenBank KJ009562.
Descritores: Microbiologia do Solo
Streptomyces/química
Antineoplásicos/farmacologia
-Paquistão
Filogenia
Artemia/classificação
Artemia/efeitos dos fármacos
Sais
Solo/química
Streptomyces/isolamento & purificação
Streptomyces/ultraestrutura
Streptomyces griseus/classificação
Sais de Tetrazólio
Células Vero
RNA Ribossômico 16S/genética
Cromomicinas/classificação
Cromomicinas/farmacologia
Células HeLa
Microscopia Eletrônica de Varredura
Linhagem Celular
Chlorocebus aethiops
Cromatografia/métodos
Análise de Sequência de RNA
Concentração Inibidora 50
Células MCF-7
Formazans
Glicerol/análogos & derivados
Glicerol/farmacologia
Larva/efeitos dos fármacos
Mineração
Antibacterianos/isolamento & purificação
Antibacterianos/farmacologia
Antineoplásicos/isolamento & purificação
Limites: Humanos
Animais
Bovinos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1003343
Autor: Andrade-Zuñiga, Erick M; Morales, Miguel; Ariano-Sánchez, Daniel.
Título: Toxicity of the feathers of Yellow Grosbeak, Pheucticus chrysopeplus (Passeriformes: Cardinalidae), a chemically defended neotropical bird / Toxicidad de las plumas del Picogrueso amarillo, Pheucticus chrysopeplus (Passeriformes: Cardinalidae), un ave neotropical con defensa química
Fonte: Rev. biol. trop;66(4):1530-1535, oct.-dic. 2018. tab, graf.
Idioma: en.
Resumo: Abstract Chemical defense is a widespread mechanism on many animals and plants. However, just a few cases are known for avian species. In this study we evaluate the toxicity of Pheucticus chrysopeplus feather extract via lethality test with brine shrimp (Artemia salina) as an in vivo model. Mortality of A. salina was evaluated after 24 hour exposure to artificial seawater, methanol, and the methanolic feather extract. Kruskal-Wallis test showed a significant difference in mortality between treatments (X2 = 65.25, P < 0.0001, n = 50). With this we describe P. chrysopeplus as the first known toxic avian species of Guatemala and Central America, raising awareness about its conservation and the identification of the toxic substance present in its feathers. We also highlight the possible mimicry mechanism taking part between P. chrysopeplus and two sympatric oriole species (Icterus pectoralis and I. pustulatus).(AU)

Resumen La defensa química es un mecanismo que se encuentra presente en varios animales y plantas. Sin embargo, pocos casos son conocidos para especies de aves. En este estudio evaluamos la toxicidad de extractos de plumas de Pheucticus chrysopeplus con un ensayo de letalidad utilizando artemia (Artemia salina) como modelo in vivo. La mortalidad de A. salina se evaluó luego de ser expuesta por 24 horas a agua marina artificial, metanol y extracto metanólico de plumas de P. chrysopeplus. La prueba de Kruskal-Wallis mostró que existe una diferencia significativa entre los porcentajes de mortalidad de los tratamientos evaluados (X2 = 65.25, P < 0.0001, n = 50). Con esto, describimos a P. chrysopeplus como la primera especie de ave tóxica reportada para Guatemala y Centroamérica, resaltando la importancia de su conservación, así como la identificación de la sustancia tóxica presente en sus plumas. También destacamos el posible mecanismo de mimetismo que podría estar ocurriendo entre P. Chrysopeplus y dos especies simpátricas de orioles (Icterus pectoralis e I. pustulatus).(AU)
Descritores: Artemia
Aves
Plumas
Mimetismo Biológico
-Mortalidade
Testes de Toxicidade/instrumentação
Guatemala
Limites: Animais
Responsável: BR1.1 - BIREME



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