Distribution and antimicrobial activity of Thai marine actinomycetes

A total of 41 actinomycetes were isolated from marine samples collected in Thailand. On the basis of morphology,chemotaxonomy, and 16S rRNA gene sequence analysis, they were identified as Salinispora (13 isolates),Micromonospora (11 isolates), Nocardia (1 isolate), Verrucosispora (2 isolates), and Streptomyces (14 isolates).The antimicrobial activity screening revealed that two Micromonospora isolates, 12 Salinispora isolates and 10Streptomyces isolates showed activity against Staphylococcus aureus ATCC 25923, Kocuria rhizophila ATCC 9341,Bacillus subtilis ATCC 6633, Escherichia coli NIHJ KC213, Candida albicans KF1, and Mucor racemosus IFO 4581.Based on this study, the production media and strains were the main factors that influenced the antimicrobial activity

In vitro thrombolytic potential of bioactive compounds from marine Streptomyces sp. VITJS4 / Potencial trombolítico in vitro de compostos bioativos de Streptomyces marinhos sp. VITJS4

The most practical approach to reduce morbidity and mortality of coronary heart disease (CHD) is to delay the process of thrombus by usage of clot-dissolving agents. The necessities of such safer compounds are to be critically examined for thrombolytic activity especially, from marine sources. Thrombolytic agents have been investigated as a possible treatment for thrombus. The aim of this study was to investigate the in vitro thrombolytic potential of Streptomyces sp.VITJS4 (NCIM No. 5574); (ACC No: JQ234978.1) active compounds. The fibrin degradation revealed a clear transparent zone of clearance with 500µg/mL concentration showing 24mm hydrolysis. The thrombolytic effect of Streptomyces sp.VITJS4 compounds was also demonstrated in vitro clot lysis assay where The percent of thrombolysis by the crude extract showed 90±1.7% at the concentration of 1000µg/mL, whereas percent of thrombolysis by streptokinase was found 100± 00%%. The bioactive compounds were further studied for spectrophotometric analysis. The UV-VIS profile showed different peaks ranging from 400-700 nm with different absorption respectively. The data confirmed the presence of both analogues with absorption maxima at 210 and 310 nm. A sensitive method using LC-MS technique was optimized for the separation and identification of bioactive metabolites which was indicated by the fingerprints. The results of the LC-MS analysis provided different peaks determining the presence of compounds with different therapeutic activities. The current study refers the bioactive compound as impressive thrombolytic agent for further laboratory study. Further studies should be conducted to ensure the efficacy and safety of different concentration of bioactive compounds for drug development. Hence the results reported perhaps useful for the discovery of novel thrombolytic drugs from marine origin.

A abordagem mais prática para reduzir a morbidade e a mortalidade da doença arterial coronariana (CHD, do inglês coronary heart disease) consiste em retardar o processo de trombo através da utilização de agentes de dissolução de coágulos. As necessidades de tais compostos mais seguros devem ser criticamente examinadas para a atividade trombolítica, especialmente de fontes marinhas. Agentes trombolíticos tem sido estudados como um possível tratamento para o trombo. O objetivo deste estudo foi investigar o potencial trombolítico in vitro dos compostos ativos do Streptomyces sp.VITJS4 (NCIM No. 5574); (ACC No: JQ234978.1). A degradação da fibrina revelou um clara zona livre transparente com concentração de 500µg/mL mostrando uma hidrólise de 24mm. O efeito trombolítico dos compostos de Streptomyces sp.VITJS4 também foi demonstrado no ensaio in vitro de lise dos coágulos em que a percentagem de trombólise pelo extrato bruto mostrou 90±1.7% a uma concentração de 1000µg/mL, enquanto que a percentagem de trombólise pela estreptoquinase foi de 100± 00%. Os compostos bioativos foram estudados posteriormente através da análise espectrofotométrica. O perfil ultra violeta visível (UV-VIS profile, em inglês) mostrou diferentes picos variando entre 400-700 nm com diferentes absorções respectivamente. Os dados confirmaram a presença de ambos os análogos com absorção máxima em 210 e 300 nm. Um método sensível usando a técnica LC-MS (Liquid chromatography­mass spectrometry) foi otimizado para a separação e identificação metabólitos bioativos que foram indicados pelas impressões digitais (?). Os resultados da análise LC-MS forneceram diferentes picos determinando a presença de compostos com diferentes atividades terapêuticas. O estudo atual refere-se ao composto bioativo como um agente trombolítico impressionante para futuros estudos em laboratório. Estudos futuros devem ser conduzidos para assegurar a eficácia e segurança de diferentes concentrações dos compostos bioativos para o desenvolvimento de drogas. Assim, os resultados reportados talvez sejam úteis para a descoberta de novas drogas trombolíticas de origem marinha.

Actividad antimicrobiana y sinérgica de metabolitos producidos por Streptomyces erythrogriseus M10-77 de origen marino / Antimicrobial and synergetic activity of metabolites produced by marine origin Streptomyces erythrogriseus M10-77

Los metabolitos de un actinomiceto de origen marino, identificado como Streptomyces erythrogriseus cepa M10-77, fueron evaluados por su capacidad antimicrobiana y sinérgica con antibióticos convencionales. Las pruebas de antagonismo se realizaron frente a patógenos multidrogorresistentes (MDR) de origen clínico, siendo muy efectivos principalmente frente a especies patógenas de Staphylococcus y Enterococcus. Se determinó la Concentración Mínima Inhibitoria (CMI) de extractos diclorometánicos frente a los patógenos S. aureus 1094, S. epidermidis 1093 y Staphylococcus coagulasa negativo 348, siendo estos valores de 3,9; 15,7 y 1,9 µg/mL respectivamente. Los componentes del extracto diclorometánico fueron fraccionados parcialmente, obteniéndose hasta 4 fracciones orgánicas (I, II, III, IV), las que mostraron actividades inhibitorias de la cepa referencial S. aureus ATCC 43300. Los bioensayos frente a S. aureus meticilino resistente (MRSA) mostraron actividad sinérgica de la fracción II del extracto con antibióticos betalactámicos y aminoglucósidos, resaltando la repotenciación de la actividad de la bencilpenicilina en 128 veces el valor basal; así como de la gentamicina en 8 veces sobre el valor basal. S. erythrogriseus cepa M10-77 resultó ser un productor de metabolitos antibacterianos de alta potencia y con actividad sinérgica con antibióticos de referencia médica.

Metabolites of a marine actinomycete, identified as Streptomyces erythrogriseus M10-77 strain were evaluated for antimicrobial and synergistic activity with conventional antibiotics. Antagonism tests were conducted against multidrug resistant (MDR) pathogens of clinical origin, being very effective mainly against pathogenic Staphylococcus and Enterococcus. Minimum Inhibitory Concentrations (MIC) of dichloromethane extracts were determined against pathogenic S. aureus 1094, S. epidermidis and coagulase-negative Staphylococcus 1093 348, these values being 3.9; 15.7 and 1.9 μg/mL respectively. The components of dichloromethane extracts were fractionated partially yielding four organic fractions (I, II, III, IV), which showed inhibitory activity against the reference strain S. aureus ATCC 43300. The bioassays against S.aureus methicillin-resistant (MRSA ) produced synergistic activity of the extract fraction II with beta-lactams and aminoglycoside antibiotics, highlighting the upgrading of the activity of penicillin at 128 times above the baseline and gentamicin 8-fold above baseline. S. erythrogriseus M10-77 strain proved to be a producer of antibacterial metabolites with high power and synergistic activity with antibiotics of medical use.

Antimicrobial, Antioxidant and Cytotoxic Activity of Marine Streptomyces parvulus VITJS11 Crude Extract

The main aim of the study was to evaluate the bioactive properties of ethyl acetate crude extract of Streptomyces parvulus VITJS11 with a view to assess their therapeutic potential. The biological activity of ethyl acetate extract was tested against fungal and bacterial pathogens. The free radical scavenging potential of the crude extract was determined by DPPH assay. The chemo preventive properties of S. parvulus VITJS11 ethyl acetate extract was examined by MTT assay on HepG2 cells. The morphological, physiological and the biochemical properties of the strain S. parvulus VITJS11 was confirmed by conventional methods. Genotypic characterization was done using 16S r-DNA partial gene amplification and sequencing. The authenticity of the crude chemical constitutes were determined by the GC-MS. The ethyl acetate extract of VITJS11 showed maximum antifungal activity against three Aspergillus species and prominent antibacterial activity against two Gram positive and Gram negative bacteria at 20 mg/mL. The antioxidant potential of the crude extract exhibited strong reducing power activity at 5mg/ mL with 85% inhibition and the cytotoxic effect was found with IC50 of 500µg/ mL on HepG2 cell lines. The GC-MS analysis and the chromatogram patterns revealed 16 peaks, indicating the presence of bioactive constituents, which included several important organic compounds, namely 9-(2',2'-dimethylpropanoilhydrazono)-3,6-dichloro-2,7-Bis-[2-(diethylamino)-ethoxy]fluorine (23.1) Dotriacontylpentafluoropropionate,(25.0) Octadecanoic acid, (20.0); Trans-2-methyl-4-n-butylthiane, S, S-dioxide.(19.0). The results showed the benefit of ethyl acetate extract from S. parvulus VITJS11 in treating microbial infections and indicated their broad spectrum of activity with beneficial virtues for therapeutic use.

Hyoscyamine-producing marine Actinomycetes from lagos lagoon sediment

Objective: To isolate and screen Actinomycetes from Lagos Lagoon soil sediments for production of bioactive metabolites. Methods: Sediment samples were collected from four different locations of Lagos Lagoon and were dried for 2 weeks after which the Actinomycetes were isolated by serial dilution using the spread plate method on starch casein and Kuster's agar supplemented with 80 μg/ mL cycloheximide to prevent fungal growth. The plates were incubated at 28 °C for 1-2 weeks. Isolates were selected based on their colonial characteristics as well as their Gram's reaction and subcultured using the same media for isolation until pure cultures were obtained and incubated at 28 °C for 3 d. Thereafter, they were inoculated into starch casein and Kuster's broth media and incubated for 8 d. The secondary metabolites were screened for antimicrobial activity against the following microorganisms: methicillin resistant Staphylococcus aureus, Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 29522, Pseudomonas aeruginosa ATCC 27853, Candida albicans and Enterococcus faecalis ATCC 29212. Coagulasenegative staphylococci isolated from HIV patients were also used (Staphylococcus warneri, Staphylococcus xylosus and Staphylococcus epidermidis). The antimicrobial metabolites of the Actinomycetes isolates were identified using gas chromatography (GC). Results: Crude extracts of isolates showed antimicrobial activity against some of the test organisms. The GC data analysis showed the antibiotic profile of these isolates. Conclusions: Analysis of the crude extracts of the isolates using GC method, revealed the presence of antibiotics including an anticholinergic hyoscyamine among other conclusions.

Violapyrone J, alpha-Pyrone Derivative from a Marine-derived Actinomycetes, Streptomyces sp

A new alpha-pyrone derivative, violapyrone J (1), and along with the two known violapyrones B (2) and C (3) were isolated from the fermentation broth of a marine actinomycete Streptomyces sp. SC0718. The structure of violapyrone J (1) was elucidated from 1D and 2D NMR spectroscopic analyses.

Production and purification of a bioactive substance against multi-drug resistant human pathogens from the marine-sponge-derived Salinispora sp

Objective: To isolate, purify, characterize, elucidate structure and evaluate bioactive compounds from the sponge-derived Salinispora sp. FS-0034. Methods: The symbiotic actinomycete strain FS-0034 with an interesting bioactivity profile was isolated from the Fijian marine sponge Theonella sp. Based on colony morphology and obligatory requirement of seawater for growth, and mycelia morphological characteristics the isolate FS-0034 was identified as a Salinispora sp. The bioactive compound was identified by using various spectral analysis of ultraviolet, high resolution electrospray ionization mass spectroscopy, 1H nuclear magnetic resonance, correlated spectroscopy and heteronuclear multiple bond coherence spectral data. A minimum inhibitory concentration assay were performed to evaluate the biological properties of the pure compound against multi-drug resistant pathogens. Results: Bioassay guided fractionation of the ethyl acetate extract of the culture of Salinispora sp. FS-0034 by different chromatographic methods yielded the isolation of an antibacterial compound, which was identified as rifamycin W (compound 1). Rifamycin W was reported for its potent antibacterial activity against methicillin-resistant Staphylococcus aureus, wild typeStaphylococcus aureus and vancomycin-resistant Enterococcus faecium and displayed minimum inhibitory concentrations of 15.62, 7.80 and 250.00 μg/mL, respectively. Conclusions:The present study reported the rifamycin W from sponge-associated Salinispora sp. and it exhibited appreciable antibacterial activity against multi-drug resistant human pathogens which indicated that sponge-associated Actinobacteria are significant sources of bioactive metabolites.

Isolation and Identification of Marine Actinomycetes with Quorum Sensing Inhibitory Activity / 微生物学通报

Quorum sensing systems of pathogens are central regulators for the expression of virulence factors. Increasing evidence implies that targeting the quorum sensing system of many pathogenic bacteria is a promising therapeutic approach to control infections. In this work,we isolated 47 strains of actinomycetes from the mud sample of Jiaozhou Bay. Quorum sensing inhibitory activity was monitored by Chromobacterium violaceum CV026. As a result,the culture broth extract of actinomycetes WA-7 was found to have significant quorum sensing inhibitory activity. This strain was assigned to the genus Streptomyces based on its 16S rDNA sequence. Further investigation revealed that the extract could inhibit the quorum sensing-controlled violacein and proteases production of C. violaceum in a concentration-dependent manner.

Study on Cytotoxic Activity and Chemical Constitunents of Marine Actinomycets Strain 124092 / 微生物学通报

The hexane extract from marine actinomycetes 124092 showed potent inhibition on B16 cell line by MTT assay. The hexane extract was fractionationed on silica gel column by vacuum liquid chromatography to afford 6 fractions(Fr1~Fr6), and Fr6 showed cytotoxic activity. To determine the bioacitve components of hexane extract, Fr6 was analyzed by GC/MS. The main components were identified as palmitic acid (11.76%), oleic acid (12.16%), linoleic acid (14.77%), and lactobacillic acid (61.31%). It have been reported that palmitic acid, oleic acid, and linoleic acid possess cytotoxic activity on rat ascites tumor cells and linoleic acid have suppressive effect on human lung adenocarcinoma cells.