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Isolation and characterization of marine-derived actinomycetes with cytotoxic activity from the Red Sea coast 被引量:3
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作者 Mohamed Saleh Abdelfattah Mohammed Ismail Youssef Elmallah +2 位作者 Usama Wahid Hawas Lamia Taha Abou El-Kassema Mennat Allah Gamal Eid 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第8期651-657,共7页
Objective: To isolate and evaluate the cytotoxic activity of different actinomycetes species isolated from the Red Sea coast in Sharm el-Sheikh, Egypt.Methods: Forty actinomycetes strains were isolated from different ... Objective: To isolate and evaluate the cytotoxic activity of different actinomycetes species isolated from the Red Sea coast in Sharm el-Sheikh, Egypt.Methods: Forty actinomycetes strains were isolated from different sediments and seawater samples collected from the Red Sea coast in Egypt. Actinomycetes were recognized by morphological and microscopic examinations. Cell viability and cytotoxicity induced by the crude extracts on breast cancer cell lines MDA-MB-231 were assessed using methylene blue assay. The strains with promising cytotoxic activity were identified by sequencing and amplifying the 16 S r RNA genes. The antibacterial activities of the crude extracts were performed using Kirby–Bauer disc diffusion method.Results: The results indicated that five ethyl acetate extracts exhibited cytotoxicity towards breast cancer cell lines MDA-MB-231. The highest cytotoxic activity was found for the ethyl acetate extracts of EGY2 and EGY39. The isolate EGY3 was identified as a new Streptomyces species, while the actinomycete EGY22 was found to be a member of the genus Nocardiopsis sp. The crude extract of the isolate EGY8 showed slightly high antimicrobial activity against different test microorganisms.Conclusions: The results of the present study reveal that marine sediments of the Red Sea are a potent source of novel species of actinomycetes. The isolates may be useful in discovery of novel bioactive compounds and an important step in the development of microbial natural product research. 展开更多
关键词 Red Sea Breast cancer actinomycetes 16S RRNA CYTOTOXICITY
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Bioactive chemical constituents from the marine-derived fungus Cladosporium sp.DLT-5
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作者 Luting DAI Qingyi XIE +6 位作者 Jiaocen GUO Qingyun MA Li YANG Jingzhe YUAN Haofu DAI Zhifang YU Youxing ZHAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期905-914,共10页
A new isochromanone,cladosporinisochromanone(1),accompanied by 15 known compounds(2–16)were obtained from secondary metabolites produced by marine-derived fungus Cladosporium sp.DLT-5.NMR and HRESIMS spectra elucidat... A new isochromanone,cladosporinisochromanone(1),accompanied by 15 known compounds(2–16)were obtained from secondary metabolites produced by marine-derived fungus Cladosporium sp.DLT-5.NMR and HRESIMS spectra elucidation determined the planar structure of 1.Subsequent electronic circular dichroism(ECD)experiment assigned the absolute configuration of 1.Compounds 1,2,4–6,and 10 displayed different degrees of neuroprotective activities on human neuroblastoma cells SH-SY5Y.Five compounds(1,3–5,and 13)emerged resistance to protein tyrosine phosphatase 1B(PTP1B),further kinetic analysis and molecular docking study indicated that the most potent compound 13(IC50value of 10.74±0.61μmol/L)was found as a noncompetitive inhibitor for PTP1B.Surface plasmon resonance(SPR)and molecular docking studies also demonstrated the interaction between compound 12 and Niemann-Pick C1 Like 1(NPC1L1),which has been identified as significant therapeutic target for hypercholesteremia.In addition,compounds 3,6,and 14 showed attractive inhibitory activity against the phytopathogenic fungi:Colletotrichum capsici.Therefore,library of Cladosporium metabolites is enriched and new active uses of known compounds are explored. 展开更多
关键词 Cladosporium sp. marine-derived fungus neuroprotective effects protein tyrosine phosphatase 1B(PTP1B) Niemann-Pick C1 Like 1(NPC1L1) antifungal activity
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Isolation, Examination and Characterization of Actinomycetes as a Source of Antimicrobial Agents from Libyan Soil
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作者 Galal S. Salem Saleh H. Baiu Ali A. Ali 《Advances in Bioscience and Biotechnology》 2023年第6期322-336,共15页
The rapid increase of bacterial resistance strains to multiple antibiotics has become a global public health concern. In the present study, actinomycetes from different districts of Libyan soil were isolated and scree... The rapid increase of bacterial resistance strains to multiple antibiotics has become a global public health concern. In the present study, actinomycetes from different districts of Libyan soil were isolated and screened for their inhibitory activity against pathogenic bacteria and fungi. Three hundred soil samples were taken from 77 diverse ecosystems, including deserts, forests, pastureland, and cropland located in different climatic regions in Libya. A total of 164 actinomycetes were obtained. Of 164 isolates, 38 (23.2%) isolates were morphologically and microscopically characterized by spore chain and surface morphology, aerial and substrate mycelia and soluble pigments. The preliminary classification of the isolates illustrates that all isolates belong to the genus Streptomyces. These isolates were further examined for their antagonistic potential against nine pathogenic bacteria and fungi. Out of 38, 11 (28.9%) isolates showed their capability to produce inhibitory substances against at least two tested strains. Among bacterial strains, Staphylococcus aureus was susceptible to almost all eleven isolates (90.9%), while Streptococcus pyogenes was found to be resistant to most selected isolates (18.2%). The isolate, 063 (Wadan soil-desert zone) was the only isolate that exhibited broad spectrum antimicrobial activity against all tested pathogenic microbes, and hence was selected for further study. According to its cultural, morphological, physiological, and biochemical characteristics, the isolate 063 was identified as Streptomyces rochei. The results obtained indicate that the Libyan soil, particularly in extreme environments, could be a potent source of bioactive metabolites with antimicrobial potency against a wide variety of microbial pathogens. Thus, this investigation suggested that exploring new habitats in unexplored and untapped regions of Libya could provide a promising source of biologically active compounds for therapeutic applications. 展开更多
关键词 actinomycetes Antimicrobial Activity ISOLATION STREPTOMYCES
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Isolation and phylogenetic assignation of actinomycetes in the marine sediments from the Arctic Ocean 被引量:8
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作者 YU Yong LI Huirong ZENG Yinxin CHEN Bo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第6期135-142,共8页
Actinomycetes in five marine sediments collected from the Arctic Ocean atdepths of 43 to 3 050 m were cultivated using a variety of media. A total of 61 actinomycetecolonies with substrate mycelia only were observed, ... Actinomycetes in five marine sediments collected from the Arctic Ocean atdepths of 43 to 3 050 m were cultivated using a variety of media. A total of 61 actinomycetecolonies with substrate mycelia only were observed, and no colonies with aerial mycelia wereobserved under aerobic conditions at 15℃. From these colonies, 28 were selected to representdifferent morphological types. Denaturing gradient gel electrophoresis (DGGE) was used to check thepurity of isolates and select representatives for subsequent sequencing. Phylogentic analyses basedon nearly full-length 16S ribosomal RNA gene (rDNA) sequences indicated that the actinomycetesisolated were accommodated within genus Rhodococcus of family Nocardiaceae, genus Dietzia of familyDietziaceae, genera Janibacter and Terrabacter of family Instrasporangiaceae and genera Kocuria andA nhrobacter of family Micrococcaceae. One of the strains (P27-24) from the deep-sea sediment atdepth of 3 050 m was found to be identical in 16S rDNA sequence(1474/1474) with theradiation-resistant Kocuria rosea ATCC 187~T isolated from air. More than half of the isolatesshowed the similarities ranging from 99.5% to 99.9% in 16S rDNA sequence to dibenzofran-degrading,butyl 2-ethylhexanoate-hydrolysising and nitrile-metabolizing actinomycetes. All the strainsisolated were psychrotolerant bacteria and grew better on the media prepared with natural seawaterthan on the media prepared with deionized water. Three of them (Dietzia sp. P27-10, Rhodococcus sp.S11-3 and Rhodococcus sp.P11-5) had an obligate growth requirement for salt, confirming that thesestrains are indigenous marine actinomycetes. 展开更多
关键词 marine actinomycetes genetic diversity arctic ocean
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Isolation and characterization of potential antibiotic producing actinomycetes from water and sediments of Lake Tana,Ethiopia 被引量:12
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作者 Gebreselema Gebreyohannes Feleke Moges +1 位作者 Samuel Sahil Nagappan Raja 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第6期426-435,共10页
Objective:To isolate,evaluate and characterize potential antibiotic producing actinomycetes from water and sediments of Lake Tana,Ethiopia.Methods:A total of 31 strains of actinomycetes were isolated and tested agains... Objective:To isolate,evaluate and characterize potential antibiotic producing actinomycetes from water and sediments of Lake Tana,Ethiopia.Methods:A total of 31 strains of actinomycetes were isolated and tested against Gram positive and Gram negative bacterial strains by primary screening.In the primary screening.11 promising isolates were identified and subjected to solid state and submerged state fermentation methods to produce crude extracts.The fermented biomass was extracted by organic solvent extraction method and tested against bacterial strains by disc and agar well diffusion methods.The isolates were characterized by using morphological,physiological and biochemical methods.Results:The result obtained from agar well diffusion method was belter than disc diffusion method.The crude extract showed higher inhibition zone against Gram positive bacteria than Cram negative bacteria.One-way analysis of variance confirmed most of the crude extracts were statistically significant at 95%confidence interval.The minimum inhibitor)concentration and minimum bactericidal concentration of crude extracts were 1.65 mg/mL and 3.30 mg/mL against Staphylococcus aureus,and 1.84 mg/mL and 3.80 mg/mL against Escherichia coli respectively.The growth of aerial and substrate mycelium varied in different culture media used.Most of the isolates were able to hydrolysis starch and urea:able to survive at 5%concentration of sodium chloride:optimum temperature for their growth was 30°C.Conclusions:The results of the present study revealed that freshwater actinomycetes of Luke Tana appear to have immense potential as a source ol antibacterial compounds. 展开更多
关键词 actinomycetes Solid STATE FERMENTATION Submerged STATE FERMENTATION Disc DIFFUSION METHOD Agar well DIFFUSION METHOD Crude extracts Antibiotics Antibacterial activity
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Clear felling and burning effects on soil nitrogen transforming bacteria and actinomycetes population in Chittagong University campus, Bangladesh 被引量:4
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作者 S.M. Sirajul Haque Rahima Ferdoshi +1 位作者 Sohag Miah M. Nural Anwar 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第1期123-130,共8页
The effect of forests clear felling and associated burning on the population of soil nitrogen transforming bacteria and actinomycetes are reported at three pair sites of Chittagong University campus, Bangla- desh in m... The effect of forests clear felling and associated burning on the population of soil nitrogen transforming bacteria and actinomycetes are reported at three pair sites of Chittagong University campus, Bangla- desh in monsoon tropical climate. Clear felled area or burnt site and 15-21 year mixed plantation of native and exotic species, situated side by side on low hill having Typic Dystrochrepts soil was represented at each pair site. At all the three pair sites, clear felled area or burnt site showed very significantly (p~_0.001) lower population of actinomycetes, Rhizobium, Nitrosomonas, Nitrobacter and ammonifying as well as deni- trifying bacteria compared to their adjacent mixed plantation. From en- vironmental consideration, this finding has implication in managing natural ecosystem. 展开更多
关键词 Nitrogen transforming bacteria actinomycetes forest clearfelling effects burning effects soil microorganisms Chittagong HillTracts
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Diversity and bioactivity of actinomycetes from Signy Is-land terrestrial soils,maritime Antarctic 被引量:2
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作者 Shing Yi Pan Geok Yuan Annie Tan +2 位作者 Peter Convey David A.Pearce Irene K.P.Tan 《Advances in Polar Science》 2013年第4期208-212,共5页
The Antarctic represents a largely untapped source for isolation of new microorganisms with potential to produce bio- active natural products. Actinomycetes are of special interest among such microorganisms as they ar... The Antarctic represents a largely untapped source for isolation of new microorganisms with potential to produce bio- active natural products. Actinomycetes are of special interest among such microorganisms as they are known to produce a large number of natural products, many of which have clinical, pharmaceutical or agricultural applications. We isolated, characterized and classified actinomycetes from soil samples collected from different locations on Signy Island, South Orkney Islands, in the maritime Antarctic. A total of 95 putative actinomyeete strains were isolated from eight soil samples using eight types of selective isolation media. The strains were dereplicated into 16 groups based on morphology and Amplified Ribosomal DNA Restriction Analysis (ARDRA) patterns. Analysis of 16S rRNA gene sequences of representatives from each group showed that streptomy- cetes were the dominant actinomycetes isolated from these soils; however, there were also several strains belonging to diverse and rare genera in the class Actinobacteria, including Demetria, Glaciibacter, Kocuria, Marmoricola, Nakamurella and Tsukamurella. In addition, screening for antibacterial activity and non-ribosomal peptide synthetase genes showed that many of the actinomycete strains have the potential to produce antibacterial compounds. 展开更多
关键词 actinomycete diversity ANTARCTICA rare actinomycetes non-ribosomal peptide synthetase genes
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Distribution of actinomycetes in oil contaminated ultisols of the Niger Delta(Nigeria) 被引量:2
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作者 J.P. Essien 1, E. D. Udosen 2 (1. Department of Microbiology, University of Uyo, Nigeria 2. Department of Chemistry and Biochemistry, University of Uyo,Nigeria) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第3期296-302,共7页
The distribution of actinomycetes in oil contaminated sandy loam ultisols of the Niger Delta region of Nigeria was studied to aid in understanding the effect of hydrocarbons on indigenous microbial population in trop... The distribution of actinomycetes in oil contaminated sandy loam ultisols of the Niger Delta region of Nigeria was studied to aid in understanding the effect of hydrocarbons on indigenous microbial population in tropical soils. The average total counts of actinomycetes in all the oil samples analysed was 10 3 cfu/g. Higher counts of actinomycetes were observed during the dry season than during the wet season. The counts of hydrocarbonoclastic actinomycetes correlated positively with the total count of actinomycetes. The actinomycetes were generally restricted to the top soil(0—10 cm soil depth) although a seemingly deeper(down to 40 cm soil depth) distribution was noticed in the dry season. The isolates included oil degrading species of Actinoplanes, Norcadia, Streptomyces and Streptosporangium. Their high oil utilization ability indicates their positive potential and role in the bioremediation of oil spilled soils. 展开更多
关键词 actinomycetes oil contaminated ultisols
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Bioprospection of marine actinomycetes: recent advances,challenges and future perspectives 被引量:1
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作者 Swati Sharma Abhay B. Fulke Asha Chaubey 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第6期1-17,共17页
In exploring new sources for economically important products, marine environment draws particular attention because of its remarkable diversity and extreme conditions;it is known to produce metabolic products of great... In exploring new sources for economically important products, marine environment draws particular attention because of its remarkable diversity and extreme conditions;it is known to produce metabolic products of great value. It represents untapped source for the discovery of novel secondary metabolites with varying potential such as antibiotic, anti-tumor, antifouling and cytotoxic properties. Marine actinomycetes distributed throughout the marine environment from shallow to deep sea sediments have proved to be a finest source for this discovery. Secondary metabolites derived from marine actinomycetes have proved their worth in industries based on the research on their properties and wide range applications. Spotlight of the review is range of marine based actinomycetes products and significant research in this field. This shows the capability of marine actinomycetes as bioactive metabolite producers. Additionally, the present review addresses some effective and novel approaches of procuring marine microbial compounds utilizing the latest screening strategies of drug discovery from which traditional resources such as marine actinobacteria has decreased due to declining yields. The aim is in the context of promoting fruitful and profitable results in the near future. The recent surfacing of new technologies for bioprospection of marine actinomycetes are very promising, resulting in high quality value added products, and will be de?ning a new era for bioactive compounds with medical and biotechnological applications. 展开更多
关键词 MARINE actinomycetes bioprospection COMMERCIAL use bioactive COMPOUNDS GENOME MINING
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Hyoscyamine-producing marine Actinomycetes from Lagos Lagoon sediment 被引量:1
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作者 Davies Olabisi Flora Adeleye Isaac Adeyemi Wang Peng George 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第3期196-201,共6页
Objective:To isolate and screen Actinoniycetes from Lagos Lagoon soil sediments for production of bioactive metabolites.Methods:Sediment samples were collected from four different locations of Lagos Lagoon and were dr... Objective:To isolate and screen Actinoniycetes 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 Actinoniycetes were isolated by serial dilution using the spread plate method on starch casein and Kuster's agar supplemented with 80 ug/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 subciiltured 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 Enterocolitis faecal is ATCC 29212.Coagulasenegative staphylococci isolated from HIV patients were also used(Staphylococcus warneri.Staphylococcus xylosus and Staphylococcus epidennidis).The antimicrobial metabolites of the Actinoniycetes 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. 展开更多
关键词 Marine actinomycetes STREPTOMYCES Antimethicillin resistance Molecular identification MORPHOLOGICAL characteristics Gas chromatography
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Caerulomycin A—An Antifungal Compound Isolated from Marine Actinomycetes 被引量:2
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作者 Vaibhav Ambavane Pradipta Tokdar +5 位作者 Rajashri Parab E. S. Sreekumar Girish Mahajan Prabhu Dutt Mishra Lisette D’Souza Prafull Ranadive 《Advances in Microbiology》 2014年第9期567-578,共12页
Actinomycetes have been prolific sources of novel secondary metabolites with a range of biological activities that may ultimately find application as therapeutic compounds. Hence several drug discovery companies are e... Actinomycetes have been prolific sources of novel secondary metabolites with a range of biological activities that may ultimately find application as therapeutic compounds. Hence several drug discovery companies are engaged in isolation of novel bioactive metabolites from these microbial sources. Antibiotics form the major class of such bioactive metabolites and have been widely used for treating infectious diseases. One of the most critical problems in clinical practice is the increase of prevalence of drug resistant strains, especially azole resistance among fungi. Due to this, there is a constant need for development of new antifungal antibiotics having novel scaffolds and/or mechanism of action. In our in-house screening program in the quest of novel and superior antifungal compounds, an actinomycetes strain PM0525875 was isolated from a marine invertebrate. The extracts of this microbe showed potent in-vitro antifungal activity against drug resistant fungal strains. The antifungal active peak from the extract obtained by shake flask fermentation was identified by chromatographic and other analytical techniques during bioactivity guided isolation. Later the fermentation conditions were optimized in 30 L fermentor for the production of sufficient amount antifungal compound for complete structural characterization. Consequently the fermented broth extract was subjected to bioactivity-guided fractionation, to isolate the active principle using different preparative chromatographic techniques followed by its characterization. The active principle was characterized to be Caerulomycin A. Minimum inhibitory concentration (MIC) of the compound was found in the range of 0.39 - 1.56 μg/ml against pathogenic fungal test strains. The phylogenetic analysis of producer strain using 16S rRNA sequence showed closest match with Actinoalloateichus cyanogriseus. Herewith we report the isolation of Caerulomycin A from marine invertebrate-associated Actinoalloteichus sp. using optimized medium and fermentation conditions. 展开更多
关键词 Caerulomycin A ANTIFUNGAL Non-Polyene Actinoalloateichus cyanogriseus MARINE actinomycetes
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High Ethanol Production by Marine-Derived Yeasts-<i>Saccharomyces cerevisiae</i>under Stress Pressures 被引量:1
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作者 Naoto Urano Ayaka Shirao +1 位作者 Masahiko Okai Masami Ishida 《Advances in Microbiology》 2017年第5期349-357,共9页
For practical applications of bioethanol, the uses of both highly concentrated biomass materials and their effective fermentation by yeasts are indispensable in order to produce ethanol at low costs. However, as the s... For practical applications of bioethanol, the uses of both highly concentrated biomass materials and their effective fermentation by yeasts are indispensable in order to produce ethanol at low costs. However, as the saccharified products of those biomass generally contain abundant sugars, the yeasts are affected by the compounds and are inclined to decrease their physiological activities. In the process of fermentation, ethanol is gradually produced by the yeasts in the culture;the concentrated metabolic product also damages itself, and inhibition of the fermentation frequently occurs. The application of yeasts with high fermentative activities under stress pressures such as sugars and ethanol is thus desired for bioethanol production. In this study, various types of high-fermentative yeasts under stress pressures were isolated mainly from coastal waters in Japan and characterized. All yeast strains with high fermentative activities under 20% v/v ethanol were found to be Saccharomyces cerevisiae. The HK21 strain isolated from Tokyo Bay and identified as S. cerevisiae had the highest fermentation activity under 30% w/v sorbitol and under 20% v/v ethanol, and it produced approx. 70 g/l (9% v/v) ethanol from the 15% w/v glucose solution at 25 oC within 5 days. 展开更多
关键词 marine-derived YEAST Fermentation BIOETHANOL Coastal Water SACCHAROMYCES cerevisiae Stress Pressure
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Diversity and Bioactivity of Actinomycetes from Marine Sediments of the Yellow Sea 被引量:2
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作者 ZHANG Shumin YE Liang TANG Xuexi 《Journal of Ocean University of China》 SCIE CAS 2012年第1期59-64,共6页
Among the 116 actinomycetes collected from marine sediments of the Yellow Sea,56 grew slowly and appeared after 2?3 weeks of incubation.Among the 56 strains,only 3 required seawater(SW) for growth,and 21 grew well in ... Among the 116 actinomycetes collected from marine sediments of the Yellow Sea,56 grew slowly and appeared after 2?3 weeks of incubation.Among the 56 strains,only 3 required seawater(SW) for growth,and 21 grew well in the medium prepared with SW rather than distilled water(DW),while the remaining 32 grew well either with SW or with DW.Six representatives with different morphological characteristics,including 1 SW-requiring strain and 5 well-growing with SW strains,were selected for phy-logenetic analysis based on 16S rRNA gene.Two strains belong to Micrococcaceae and Nocardiopsaceae respectively.The other 4 strains belong to the family of Streptomycetaceae.In the analyzed 6 strains,one was related to Nocardiopsis spp.and the other three were related to Streptomyces spp.,representing new taxa.Bioactivity testing of fermentation products from 3 SW-requiring strains and 21 well-growing with SW strains revealed that 17 strains possessed remarkable activities against gram-positive pathogen or/and tumor cells,suggesting that they were prolific resources for natural drug discovery. 展开更多
关键词 海洋沉积物 生物活性 放线菌 黄海 多样性 系统发育分析 RRNA基因 生长缓慢
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Inhibition of norsolorinic acid accumulation to Aspergillus parasiticus by marine actinomycetes 被引量:1
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作者 闫培生 史翠娟 +3 位作者 沈继红 王凯 高秀君 李平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第6期1264-1269,共6页
Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and ... Thirty-six strains of marine actinomycetes were isolated from a sample of marine sediment collected from the Yellow Sea and evaluated in terms of their inhibitory activity on the growth of Aspergillus parasiticus and the production of norsolorinic acid using dual culture plate assay and agar diffusion methods.Among them,three strains showed strong antifungal activity and were subsequently identified as Streptomyces sp.by 16 S rRNA gene sequencing analysis.The supernatant from the fermentation of the MA01 strain was extracted sequentially with chloroform and ethyl acetate,and the activities of the extracts were determined by tip culture assay.The assay results show that both extracts inhibited mycelium growth and toxin production,and the inhibitory activities of the extracts increased as their concentrations increased.The results of this study suggest that marine actinomycetes are biologically important for the control of mycotoxins,and that these bacteria could be used as novel biopesticides against mycotoxins. 展开更多
关键词 海洋放线菌 寄生曲霉 抑制作用 积累 抑制活性 RRNA基因 茎尖培养 菌丝生长
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Distribution and generic composition of culturable marine actinomycetes from the sediments of Indian continental slope of Bay of Bengal 被引量:2
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作者 Surajit DAS P. S. LYLA S. AJMAL KHAN 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期166-177,共12页
从孟加拉的海湾的大陆坡沉积的放射菌类人口被学习。样品在 2004 在 FORV Sagar Sampada 的二次航行期间被收集(5 月 6 月) 并且 2005 (我的) 分别地从 11 横断(每横断有 ca。200 m, 500 m,和 1 000 m 深度驻扎) 。overlying 的物理... 从孟加拉的海湾的大陆坡沉积的放射菌类人口被学习。样品在 2004 在 FORV Sagar Sampada 的二次航行期间被收集(5 月 6 月) 并且 2005 (我的) 分别地从 11 横断(每横断有 ca。200 m, 500 m,和 1 000 m 深度驻扎) 。overlying 的物理化学的参数流水,并且沉积样品也被记录。放射菌类人口分别地在二巡航期间从 5.17 ~ 51.94 CFU/g 干燥沉积重量和 9.38 ~ 45.22 CFU/g 干燥沉积重量。没有放射菌类殖民地在 1 000 m 深度从车站被孤立。双向方差分析在车站之中显示出重要变化(ANOVA 双向, P < 0.05 ) ,但是没有意义在二巡航之间被发现(ANOVA 双向, P < 0.05 ) 。在在在两巡航的 500 m 深度的车站的人口比有统计上不足道的差别的 200 个 m 深度车站的高(ANOVA 双向, P > 0.05 ) 。三个放射菌类类被识别。Streptomyces 被发现是在两个的统治的那巡航,由 Micromonospora,和放线菌列在后面。Streptomyces 的孢子孤立在螺线孢子链显示出丰富。孢子表面是光滑的。揭示的多重回归分析影响物理化学的因素是沉积氢指数,沉积温度, TOC,孔,咸度,和压力。在现在的学习使用的媒介与海水被准备。因此,他们可以代表本土的海洋的植物群并且为改编否认陆地流量马车的理论进海到海水和沉积的咸度。 展开更多
关键词 海洋放线菌 基因重组 生物化学 大陆架 孟加拉湾
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Screening of Actinomycetes from Medicinal Plant Rhizosphere Soils for Industrial Enzymes and Antimicrobial Activity
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作者 Lukcha Vililuk Tanaporn Wongkuan +1 位作者 Supalak Yacharone Ekachai Chukeatirote 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第3期23-28,共6页
This study aimed to investigate the production of some metabolites (i.e., antibiotics, amylases and cellulases) of terrestrial actinomycetes isolated from medicinal plant rhizosphere soils. Initially, the soil sampl... This study aimed to investigate the production of some metabolites (i.e., antibiotics, amylases and cellulases) of terrestrial actinomycetes isolated from medicinal plant rhizosphere soils. Initially, the soil samples were collected from Camellia sinensis (L) Okuntze., Peuraria mirifca Airy Shaw Suvatabandhua., Ananus comosus Merr., Elephantopus scaber Linn., Orthosiphon grandiforus Bolding., Jatropha multifda Linn. and Senna siamea. To screen and isolate actinomycetes, the soil samples were pretreated by air-drying and subsequent heat incubation. The bacterial isolates exhibiting actinomycetes features were then randomly screened for their production of amylases, cellulases and antibiotics. It was found that 130 isolates (from 136) could produce amylases; 40 (from 107) produced cellulases; and seven (from 45) exhibited antimicrobial activity. The data of this study were preliminary, and yet demonstrated a rich diversity of rhizo-actinomycetes from medicinal plants. Besides, these organisms could be an untapped source for discovering of biotechnologically useful metabolites. 展开更多
关键词 actinomycetE AMYLASE antibiotic CELLULOSE rhizosphere soil
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Characterization and Antimicrobial Susceptibility of Actinomycetes from TB Smear Negative and Retreatment Patients in Nairobi, Kenya
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作者 Frida M. Njeru Perpetual Ndungu Christine Bii 《Journal of Biosciences and Medicines》 2019年第8期1-12,共12页
Actinomycetes are opportunistic pathogens in immunosuppressive patients. Pulmonary actinomycetes infections display symptoms that mimic Mycobacteria tuberculosis and can be misdiagnosed and treated as pulmonary TB. Ac... Actinomycetes are opportunistic pathogens in immunosuppressive patients. Pulmonary actinomycetes infections display symptoms that mimic Mycobacteria tuberculosis and can be misdiagnosed and treated as pulmonary TB. Actinomycetes can be co-infection with tuberculosis leading to delayed or inappropriate treatment. This study aimed to identify and determine antimicrobial susceptibility profiles of Actinomycetes from the sputum of TB smear negative and re-treatment patients referred to TB reference facilities in Kenya. Sputum specimens were collected and direct smears stained with Gram’s reagents. Culture was done on Mueller Hinton agar and incubated at 35°C for two weeks. Identification was done using phenotypic and biochemical procedures. Confirmation of the isolates was done using Polymerase Chain Reaction. A total of 52/385 (14%) Actinomycetes were isolated and subjected to antimicrobial susceptibility testing using broth microdilution method to determine the Minimum Inhibitory Concentration. Nine antibiotics were tested which included: Amikacin, Amoxicillin/Clavulanic acid, Ceftriaxone, Ciprofloxacin, Clarithromycin, Linezolid, Doxycycline, Trimethoprim-Sulfamethoxazole and Gentamycin. Staphylococcus aureus (ATCC 25923) was used as a control. Most of the isolates were susceptible to the test antibiotics. However, four isolates showed multidrug resistance to Ceftriaxone and Clarithromycin with resistance of 11.5% and 26.9% respectively. Gentamycin and Ciprofloxacin showed the highest susceptibility of 100% and 98.1% respectively. The findings of this study confirm that Actinomycetes are significant pathogens in TB smear-negative cases. Although most antibiotics were susceptible, resistance to few antibiotics was observed;hence, there is a need for proper screening of TB smear-negative cases to detect infections by Actinomycetes and also conduct the antimicrobial susceptibility test to determine which antibiotic is effective. 展开更多
关键词 actinomycetes TUBERCULOSIS ANTIBIOTICS Resistance Kenya
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Actinomycetes from Soil of Lachung, a Pristine High Altitude Region of Sikkim Himalaya, Their Antimicrobial Potentiality and Production of Industrially Important Enzymes
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作者 Laishram Shantikumar Singh Hemant Sharma Dinabandhu Sahoo 《Advances in Microbiology》 2019年第8期750-773,共24页
Investigations on actinomycetes are profoundly significant area of research since they form major resource for bioactive compounds, antimicrobials, anticancer agents, immunosuppressants, and biological control agents.... Investigations on actinomycetes are profoundly significant area of research since they form major resource for bioactive compounds, antimicrobials, anticancer agents, immunosuppressants, and biological control agents. A total of 59 actinomycetes were isolated from the soil sample collected from Domang, Lachung, North Sikkim, Sikkim, India. Out of the total isolates, 26 isolates with unique and distinct characteristic features were selected and analysed for antimicrobial activity as well as extracellular enzyme production. Out of 26 isolates, 17 (66%) isolates exhibited different level of growth inhibition against the test microorganism. 12 (47%) isolates showed antifungal activity and six (23%) isolates showed antibacterial activity. Most of the isolates showed antifungal activity. Isolate RCS260 was found to exhibit maximum growth inhibition (60%) against Colletotrichum gloeosporioides MTCC 8021. Isolate RCS252 showed maximum growth inhibition (67%) against Bacillus subtilis MTCC 441. Out of 26 isolates, 14 (54%) isolates exhibited chitinase activity, 25 (96%) isolates showed cellulase production, 20 (77%) isolates produced amylase enzyme and 17 (65%) isolates showed positive for protease activity. Potential isolate RCS260 has been characterized and identified as Streptomyces vinaceus strain RCS260 while isolate RCS252 was identified as Kitasatospora aburavienis strain RCS252. The antagonistic profile of strain RCS260 highlights its potential as antifungal agent against phytopathogens. 展开更多
关键词 actinomycetes ANTIMICROBIAL Activity EXTRACELLULAR Enzyme PRODUCTION
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Diversity of Cultivable Actinomycetes in Tropical Rainy Forest of Xishuangbanna, China
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作者 Yi Jiang Xiu Chen +1 位作者 Yanru Cao Zhen Ren 《Open Journal of Soil Science》 2013年第1期9-14,共6页
In order to obtain much more un-known actinomycetes for discovering new drug lead, one hundred soil samples were collected from five national natural protection areas of tropical rain forests, Mengla, Menglun, Mandian... In order to obtain much more un-known actinomycetes for discovering new drug lead, one hundred soil samples were collected from five national natural protection areas of tropical rain forests, Mengla, Menglun, Mandian, Xiaomengyang and Guanping, in Xishuangbanna, Yunnan, China. 1652 purified cultures of actinobacteria were isolated from these samples by using 5 media. The 16S rRNA gene sequences of 388 selected strains were analyzed, and the phylogenetic analysis was carried out. 35 genera which belong to 8 orders and 14 families of the Class actinobacteria were identified. It is showed from research results that actinomycete diversity in tropical rain forest of Xishuangbanna is the highest comparing with all areas studied in our laboratories before. Selective isolation methods for un-known actinomycetes from soil samples, including medium and inhibitors are discussed in this paper. 展开更多
关键词 actinomycetes DIVERSITY TROPICAL RAINY FOREST XISHUANGBANNA
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Dynamism of Antimicrobial Activity of Actinomycetes—A Case Study from Undisturbed Microbial Niche
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作者 Jayshree D. Patel Mahesh Parmar +8 位作者 Purshottam Patel Pravin Rohit Ramesh Taviyad Parveen Ansari Bipasha Bhattacharya Dhaval Vyas Vipin Kumar Nirmal S. Sahay Pawan K. Singh 《Advances in Microbiology》 2014年第6期324-334,共11页
Escalation of drug resistant microbes (bacteria) had forced researchers to search new and improved therapeutic compounds from different possible sources, including metabolites secreted by the actinomycetes. The aim of... Escalation of drug resistant microbes (bacteria) had forced researchers to search new and improved therapeutic compounds from different possible sources, including metabolites secreted by the actinomycetes. The aim of this study was to evaluate the pattern of antimicrobial actinomycetes from physiologically distinct soil of different geographical locations. Forty five soil samples were collected from 5 districts of Gujarat including two sanctuaries as source of survey for bioactive actinomycetes. Crowded plate technique was used for isolation and Agar cylinder method was employed for the antimicrobial screening. A total of 171 actinomycetes were isolated and screened against eighteen pathogens responsible for causing diseases in plants and humans. Results indicate that 79% of the isolates were active against at least one of the eighteen tested pathogens. Some of the actinomycetes strain had shown strong antibacterial and antifungal activity which may be a good source of obtaining novel antimicrobials. 展开更多
关键词 actinomycetes SCREENING ANTIMICROBIAL DRUG Resistance Soil MICROFLORA
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