List of Articles Actinobacteria

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  1 - Isolation, identification and evaluation of the Actinobacteria derived from wheat farms to perform biological control of fungal diseases
  Majid Gozari Maria Mohammadizadeh mohsen gozari Maryam Rafati
  10.22034/jest.2018.13251
  Background and Objective: Nowadays pesticides are extensively used to protect food security worldwide. Due to their undesirable effects, they are considered as important environmental pollutants. Methods for pest biological control are enumerated as an alternative for c More

  Background and Objective: Nowadays pesticides are extensively used to protect food security worldwide. Due to their undesirable effects, they are considered as important environmental pollutants. Methods for pest biological control are enumerated as an alternative for chemical pesticide. This study was performed to isolate and identify the antifungal-compound-producing Actinobacteria againstAspergillus nigerfungi (stored product pest)and Bipolaris sp.(responsible for root and crown rot disease) from wheat farms of Hajiabad region, Hormozgan province. Methods: Three farming sites were sampled in this study. Actinobacteria were isolated by soil extract agar and starch casein agar media. Antifungal activities were evaluated by well diffusion agar method. Potent isolates were identified through morphological, physiological, biochemical, and genetic analysis. Findings: Approximately a total number of 207 Actinobacteria isolates were isolated. From two isolation media, the soil extract agar yielded 125 isolates and exhibited more efficacy. Results of physical treatments showed that heat treatment could isolate 85 colonies and followed by desiccation and UV treatments by 57 and 46 colonies respectively. Evaluation of the antifungal activities of 100 morphologically distinct isolates revealed that only two isolates exhibited antifungal activity against Aspergillus niger and Bipolaris sp. Identification of potent isolates according to morphological, biochemical and physiological properties showed that these isolates belong to Streptomyces genus. Genetically, identification and phylogenetic analysis based on16srRNA gene revealed a high similarity between Streptomyces sp.MG-11and Streptomyces albus (similarity: 99%) and between Streptomyces sp.MG-21 and Streptomyces griseus (similarity: 99%). Discussion and Conclusions: Results of this study suggest that Streptomyces sp. MG-11 and Streptomyces sp.MG-21can be considered as appropriate candidates for biological control studies against the selected fungal diseases in wheat farms. Manuscript profile
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  2 - Evaluation of trans-glutaminase enzyme production in native Streptomyces isolated from agricultural soils of Qom province
  Somayeh Bahri Soheil Aghaei Seyyed Mohammad Hossein Razavian Faezeh Kabiri
  Purpose: Transglutaminase enzyme is a type of protease enzyme of acyltransferase type, the bonds formed by this enzyme cause strength and stability in the products of various industries. Actinobacteria have biotechnological applications due to their ability to produce s More

  Purpose: Transglutaminase enzyme is a type of protease enzyme of acyltransferase type, the bonds formed by this enzyme cause strength and stability in the products of various industries. Actinobacteria have biotechnological applications due to their ability to produce secondary metabolites and enzymes. The present study was conducted with the aim of identifying and screening trans-glutaminase-producing actinobacterial strains from the soils of the rhizosphere area of native medicinal plants in Qom province.Materials and Methods: In this research, 100 samples of soil from agricultural fields in Qom province were collected in completely sterile conditions and after preparing successive dilutions, they were cultured on ISP3 agar culture medium. Actinobacterial isolates were screened by transglutaminase enzyme specific identifier. Environmental factors including culture medium and shaker cycle were optimized on isolate growth and enzyme production. In order to identify and investigate the phylogeny of actinobacterial isolates, phenotypic and molecular methods were used.Findings: Out of 40 actinobacterial isolates, 5 strains showed the ability to produce the enzyme, based on the halo of color change by the specific substrate N-Carbobenzoxy (CBZ). The selected isolate with the highest amount of enzyme production, in terms of 16S rRNA gene synonymy, was similar to Streptomyces genus.Conclusion: The results of this study showed that Streptomyces isolate native to agricultural soils of Qom province has a significant ability to produce transglutaminase enzyme, which was studied for the first time. This isolate can be used in various food and pharmaceutical industries to produce transglutaminase enzyme. Manuscript profile
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  3 - Production and characterization of biosurfactant by indigenous halotolerant Microbacterium sp. , isolated from Qom saline soils lake
  Seyed soheil Aghaei farzaneh fakharian Mohammd Reza Zolfaghary mohammad soleimani
  Background & Objectives: Biosurfactants are biological surface active compounds produced by fungi, yeast and bacteria. These amphiphilic compounds can reduce surface tension and interfacial tension between individual molecules. The aims of this investigation was scr More

  Background & Objectives: Biosurfactants are biological surface active compounds produced by fungi, yeast and bacteria. These amphiphilic compounds can reduce surface tension and interfacial tension between individual molecules. The aims of this investigation was screening of biosurfactant producing halotolerant Actinobacteria species from the unexplored regions of Qom saline lake. Materials & methods: About 110 soil actinobacteria isolated strains were initially screened and then teste for their ability to BS production. Conventional screening methods of BS carried out using blood hemolysis, drop collapse method,oil spreading and surface tension measurements. 16S rRNA sequencing was done for the best biosurfactant producer strain. Further the partially purified BS was characterized by TLC, FTIR and compositional analysis. BS production was optimized using different carbon & nitrogen sources and optimized by different culture conditions such as temperatures, pH and stirring rate. Results: 15 out of 110 isolates were able to tolerate high salt concentrations up to 10% . 8 isolated strains were BS producer. Isolate No.9 showed 99% similarity to Microbacterium paraoxidans by 16S rRNA gene sequencing method. Compositional analysis methods proved a glycolipid structure of BS. Sucrose and yeast extract were identified as the most appropriate carbon and nitrogen source, respectively. Maximum production of BS was obtained in pH 7,at temperature 27 oC and stirring rate 170 rpm.Conclusion: These findings emphasize that such bacterial strains with superior BS production may find their potential application in bioremediation marine and soil ecosystem. Manuscript profile
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  4 - The cytotoxicity of culture extracts of indigenous Actinobacteria of Iran using Artemia urmiana
  Sanaz Imanian Ali Mehrvar Javad Hamedi Hossein Samadi Kafil Naser Eivazian Kari
  10.30495/jmw.2022.1955768.2017
  Background & Objectives: Actinobacteria are very important in the world in terms of the production of metabolites with various biological effects. This study was conducted with the aim of investigating the toxicity of the fermented extract obtained from Actinobacter More

  Background & Objectives: Actinobacteria are very important in the world in terms of the production of metabolites with various biological effects. This study was conducted with the aim of investigating the toxicity of the fermented extract obtained from Actinobacteria isolated from some biological resources of Iran on Artemia urmiana. These isolates were deposited in University of Tehran Microorganisms Collection (UTMC).Materials & Methods: Forty-eight -76°C actinobacterial isolates were revived using ISP2 agar culture medium. Two bacterial discs were inoculated in ISP2 broth medium as a pre-cultivation medium. After 48 hours, 10 ml of the liquid was inoculated into the fermentation culture medium and heated for 7 days in a shaker incubator with 180 rpm, temperature of 28°C and pH of 7.2 ± 0.2. The fermentation broth was extracted using ethyl acetate, the solvent was evaporated using a low-pressure rotary evaporator. The toxicity of fermentation broth extracts was assayed against    40-hour Artemia urmiana nauplii.Results: According to the toxicity classification, among the all 48 isolates, 64.58% were highly toxic, 22.91% were moderate toxic, and 12.5% were in the low toxicity compounds group.Conclusion: The results showed that more than half of the tested extracts had very high lethality on Artemia urmiana in a short time. Comparing the LC50 and LT50 values of the extracts with  similar studies, it was found that these extracts have a significant biological activity and can be used as a rich source in the production of metabolites with proper biological effects.  Manuscript profile
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  5 - Marine actinobacteria: a source for discovering of new drugs
  Mohammad Nazarian Iraj Nabipour Akram Najafi
  Marine actinobacteria are virtually unlimited sources of novel secondary metabolites and are very important from therapeutic and industrial points of view. There are more than 22,000 known microbial secondary metabolites, 70% of which are produced by actinobacteria. A More

  Marine actinobacteria are virtually unlimited sources of novel secondary metabolites and are very important from therapeutic and industrial points of view. There are more than 22,000 known microbial secondary metabolites, 70% of which are produced by actinobacteria. Actinobacteria from terrestrial sources have been examined and identified since the 1950s, for many significant antibiotics, anticancer, anti-tumor and immunosuppressive activities. However, obtaining the previously discovered metabolites from terrestrial actinobacteria habitats attracted studies to different ecological habitats. The ecological role of actinobacteria in the marine environment is greatly neglected.  Currently, the existence of marine actinobacteria have received considerable attention due to the structural diversity, unique biological activities of their secondary metabolites and a growing need for the development of new and potent therapeutic agents. In recent years, newly discovered secondary metabolites have shown a range of biological activities such as antibacterial, antifungal, anticancer, antitumor, cytotoxic, anti-inflammatory, anti-parasitic, anti malaria, antiviral, antioxidant, etc. In this review, an evaluation is made on the current status of research on marine actinobacteria yielding pharmaceutically active secondary metabolites. Bioactive compounds from marine actinobacteria possess distinct chemical structures that may form the basis for synthesis of new drugs that could be used to combat resistant pathogens. With the increasing advancement in science and technology, there would be a greater demand for new bioactive compounds synthesized by actinobacteria from various marine sources in future. Manuscript profile