RESUMO
The search for new compounds effective against Mycobacterium tuberculosis is still a priority in medicine. The evaluation of microorganisms isolated from non-conventional locations offers an alternative to look for new compounds with antimicrobial activity. Endophytes have been successfully explored as source of bioactive compounds. In the present work we studied the nature and antimycobacterial activity of a compound produced by Streptomyces scabrisporus, an endophyte isolated from the medicinal plant Amphipterygium adstringens. The active compound was detected as the main secondary metabolite present in organic extracts of the streptomycete and identified by NMR spectroscopic data as steffimycin B (StefB). This anthracycline displayed a good activity against M. tuberculosis H37Rv ATCC 27294 strain, with MIC100 and SI values of 7.8 µg/mL and 6.42, respectively. When tested against the rifampin mono resistant M. tuberculosis Mtb-209 pathogen strain, a better activity was observed (MIC100 of 3.9 µg/mL), suggesting a different action mechanism of StefB from that of rifampin. Our results supported the endophyte Streptomyces scabrisporus as a good source of StefB for tuberculosis treatment, as this anthracycline displayed a strong bactericidal effect against M. tuberculosis, one of the oldest and more dangerous human pathogens causing human mortality.
Assuntos
Antraciclinas/farmacologia , Sapindaceae/metabolismo , Anacardiaceae , Antraciclinas/isolamento & purificação , Antraciclinas/metabolismo , Anti-Infecciosos/farmacologia , Antituberculosos , Endófitos/isolamento & purificação , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/metabolismo , Sapindaceae/toxicidade , Streptomycetaceae/metabolismoRESUMO
The Streptoverticillium sp. Z1 is an actinomycete isolated from the soil under Cerrado vegetation, the extract of this strain was investigated in nociceptive and inflammatory models. The Streptoverticillium extract (ExS) 50 and 100 mg/kg (s.c.) produced a significant inhibition of acetic acid-induced abdominal writhings thereby demonstrating an anti-nociceptive effect. In the tail flick test the ExS (s.c.) was inactive. This result implited that ExS does not contain opioid-like compounds with central analgesic properties. In the inflammatory models, ExS 100 and 200 mg/kg (s.c.) were able to inhibit the croton oil-induced ear edema and, ExS 200 and 500 mg/kg (s.c.) inhibited the leukocyte migration on the carrageenan-induced peritonitis. The phospholipase A2 enzymatic assay showed that the anti-inflammatory activity of ExS was not due to direct effect on phospholipase A2 activity. These data suggest that Streptoverticillium sp. produces metabolites with anti-inflammatory effect and that these metabolites are unable to directly inhibit phospholipase A2 enzyme.
Assuntos
Acetona/uso terapêutico , Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Edema/tratamento farmacológico , Dor/tratamento farmacológico , Streptomycetaceae/química , Acetona/isolamento & purificação , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/isolamento & purificação , Carragenina , Óleo de Cróton , Edema/induzido quimicamente , Masculino , Camundongos , Dor/induzido quimicamente , Microbiologia do SoloRESUMO
Streptomycetes resistant to the herbicide alachlor [2-chloro-2',6'-diethyl- N-(methoxymethyl) acetanilide] were used in degradation assays to characterize the products of alachlor biodegradation. Of six strains tested, Streptomyces sp. LS166, LS177, and LS182 were able to grow at an alachlor concentration of 144 mg l(-1) and degraded approximately 60-75% of the alachlor in 14 days, as evaluated by high performance liquid chromatography. The alachlor biodegradation products were identified by gas chromatography-mass spectrometry based on mass spectral data and fragmentation patterns. All compounds detected in these assays were similar for all streptomycetes strains tested, and involved dechlorination with subsequent N-dealkylation and cyclization of the remaining N-substituent with one of the ethyl groups to produce indole and quinoline derivatives. The enzymatic pathway used by Streptomyces sp. LS182 did not generate DEA (2',6'-diethylaniline), a carcinogenic derivative of alachlor reported in other studies. Given the high degradation rates observed here, the Streptomyces strains tested may be useful in the degradation/detoxification processes of alachlor.
Assuntos
Acetamidas/metabolismo , Herbicidas/metabolismo , Microbiologia do Solo , Streptomycetaceae/metabolismo , Poluentes Químicos da Água/metabolismo , Compostos de Anilina/metabolismo , Biodegradação Ambiental , Brasil , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de MassasRESUMO
Ninety-three wild-type isolates identified as actinomycetes were tested against 11 organochlorine pesticides (OPs): aldrin, chlordane, DDD, DDE, DDT, dieldrin, heptachlor, and heptachlor epoxides, lindane, and methoxychlor. Qualitative screening agar assays displayed 62-78% tolerance of strains to OPs. Four strains designed M4, M7, M9 and M15 were selected based on multi-OP-tolerance, and identified as members of the streptomycetes group. Different growth profiles were observed in cultures of the four selected streptomycetes cultured in synthetic medium containing 5-50 microg x l(-1) aldrin or chlordane or lindane. Increase of aldrin removal by the selected microorganisms was concomitant with the 4.8-36.0 microg x l(-1) pesticide concentration range. After 72 h of streptomycete M7 growth in synthetic medium containing 48.0 microg x l(-1) aldrin, the remaining OP concentration in the supernatant was approximately 10% of the initial concentration. Also, in stationary growth phase less than 2.5 microg x l(-1) aldrin residual concentration was detected in the medium.
Assuntos
Hidrocarbonetos Clorados , Inseticidas/metabolismo , Streptomycetaceae/fisiologia , Purificação da Água/métodos , Biodegradação Ambiental , Streptomycetaceae/isolamento & purificaçãoRESUMO
Streptoverticillium sp, bactéria pertencente a família Streptomycetaceae, foi isolada de amostras de solo do câmpus da Universidade Federal do Pernambuco, e destacou-se pela atividade antibacteriana e antifúngica de seus matabólitos secundários. O extrato etanóico bruto foi submetido ao fracionamento cromatográfigo. Das substâncias isoladas, duas apresentaram atividade antimicrobiana em relação a sete espécies de Candida. Em testes biológicos realizados em camundongos, determinou-se que a maior dose do extrato bruto na qual não houve óbitos foi de 150 mg/kg e todos os animais morreram com a administração de 600 mg/kg. Para o extrato etanóico de Streptoverticillium sp observou-se IC50 de 13 ug/mL e taxa de inibição tumoral igual a 61,5 por cento para o carcinoma de Ehrlich e 75 por cento em animais com sarcoma 180.
Assuntos
Ratos , Antifúngicos , Antifúngicos , Candida albicans , Citotoxicidade Imunológica , Streptomycetaceae , Antibacterianos/toxicidadeRESUMO
Streptomycetes constituted about 46--48 per cent of the total aerobic microflora in the cultivated horizon of the studied ferralitic tropical soil below sugar cane plantation. This streptomycete fraction of the soil microbial community was composed of 13 (or more) species of Streptomyces (S. chromofuscus, S. chromogenus, S. diastatochromogenes, S. flavochromogenes, S. griseolus, S. nigrescens, S. phaeofaciens, S. sterilis, S. violaceus, Streptomyces sp. I--III), and Streptoverticillium (Sv. aspergilloides). None of these organisms did occur, with detectable frequency of occurrence, in the root surface region of sugar cane. Here, in the rhizoplane, we found a numerically small population of streptomycetes (about 5 per cent of the total bacterial flora), composed of two species (Streptomyces sp. IV and S. griseorubiginosus) which were, however, not detected in soil samples.