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مرکز اطلاعات علمی SID1
مرکز اطلاعات علمی SID
اسکوپوس
مرکز اطلاعات علمی SID
ریسرچگیت
strs
نویسندگان: 

MOAZAMI N.

اطلاعات دوره: 
  • سال: 

    2004
  • دوره: 

    3
  • شماره: 

    Supplement 2
  • صفحات: 

    0-0
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    20451
  • دانلود: 

    9450
کلیدواژه: 
چکیده: 

The number of studies on extremophilic organisms has grown exponentially in the last few years. These exotic organisms (extremoplilees) are adapted to living at 100 c. In volcanic springs, at low temperatures in the cold polar seas, at high pressure in the deep sea, at very low and high ph values (ph 0-1 or ph 10-11) or at hight salt concentration (35%). Recent developments clearly show that cell components of extremoplilic archaea and bacteria are unique and deliver a valuable source of new biocatalysts and compounds. Since many industrial enzymes are required to function under extreme conditions, there is also a considerable commercial pressure to discover stable biocatalists in modern biotechnology. extremophiles and their cell components, therefore are expected to play an important role in the chemical, food, pharmaceutical, paper and textile industries as well as environmental biotechnology. The Iranian plateau has a very remote past which even history does not remember the sculptures and images of persepolis say of its glory. The iranian plateau, has been a stage to unique events within the spectrum of world transformations.throughout this immense and long lasting immigration from the north of africa tothe south of asia and durind all these geographical and climatic changes plants, animals and microorganisms become widely extinct. The better adapted and more efficient one appeared to substitute the extinct species, finally leading to the present form of the country. Scientists geobotanically divide the northern hemisphere of the earth into four main regions, Iran his like a connecting stretch at the intersection of these four botanic regions and situation and factors from each of these regions influence the biodiversity of Iran. Research on marine and terestrial extremopliles microorganisms was started in Persian Gulf biotechnology research center to provide high quality lab and pilot plant service for isolation, identification, maintenance and screening of new active metabolites from microorganisms of different extreme area of Iran. The results of this study will be presented in this conference.

آمار یکساله:  

بازدید 20451

دانلود 9450 استناد 0 مرجع 0
نویسندگان: 

IZADIFAR IDA | KARBALAEI HEIDARI HAMID REZA

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    3
  • شماره: 

    SUPPL. (1)
  • صفحات: 

    169-169
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    11580
  • دانلود: 

    9450
چکیده: 

Organic solvent-tolerant bacteria are a novel and unique group of extremophilic microorganisms that can thrive in many harsh conditions. These bacteria are being explored for their potential in industrial applications, since their biocatalysis contents might be active in the presence of very high concentrations of organic solvents. In the present work, a screening programme was designed to isolate a novel methanol-tolerant bacterium. Among several different isolated bacteria, strain IE-93 was chosen as a best producer of lipase in the presence of 5% methanol. Phylogenetic characterization using 16S rDNA nucleotide sequence confirmed that the strain can be placed in Stenotrophomonas genus and tentatively named Stenotrophomonas sp. strain IE-93. The secreted lipase was purified by combination of amicon concentration, Q-Sepharose and Sephacryl S-200 column chromatography. The purified enzyme showed homogeneity on SDS-PAGE with apparent molecular mass of 60 kDa. The optimum pH and temperature for the enzyme were 8.0 and 35 oC respectively. The hydrolytic activity on various substrates (C4, C8, and C18 acyl chain) revealed that the purified enzyme has the highest priority for long acyl chains. Survey on lipolytic activity of the enzyme in the presence of various concentration of methanol (from 10% to 50%) showed its reasonable stability and more than 77% of initial activity was retained after 1 h incubation in 40% methanol. In overall, long alkyl chain substrate specificity and convenience stability in the presence of methanol suggest that the isolated lipase has biotechnological applications especially in low water content reactions and biodiesel production.

آمار یکساله:  

بازدید 11580

دانلود 9450 استناد 0 مرجع 0
نشریه: 

WATER AND WASTEWATER

اطلاعات دوره: 
  • سال: 

    2022
  • دوره: 

    32
  • شماره: 

    5
  • صفحات: 

    61-69
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    72
  • دانلود: 

    46
چکیده: 

There is an urgent need for the removal of arsenic (As) from groundwater and wastewater as it is a very hazardous heavy metal for human and environmental health. In this research, Asresistant and oxidizing bacteria were isolated from the Maharloo Lake (27 km southeast of Shiraz city) and identified to a great extent. Three isolated bacillus-shaped strains (called F5, F6 and F7) tolerated up to 1 M AsNaO2, grew up to 3. 5 M NaCl and pH 12, and consumed NaSCN and Na2S2O3. The molecular analysis confirmed the originality of the strains to a high extent. The As absorption rate by these bacteria was measured by the atomic absorption method, and their effect was examined on a water sample from the south of Kerman city (Iran) and a synthetic wastewater sample with a chemical oxygen demand (COD) of about 180, 000 kg/m3 that was able to absorb high levels of arsenic.

آمار یکساله:  

بازدید 72

دانلود 46 استناد 0 مرجع 0
گارگاه ها آموزشی
اطلاعات دوره: 
  • سال: 

    1398
  • دوره: 

    6
  • شماره: 

    2
  • صفحات: 

    127-138
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    205
  • دانلود: 

    80
چکیده: 

متن کامل این مقاله به زبان انگلیسی می باشد. لطفا برای مشاهده متن کامل مقاله به بخش انگلیسی مراجعه فرمایید.لطفا برای مشاهده متن کامل این مقاله اینجا را کلیک کنید.

آمار یکساله:  

بازدید 205

دانلود 80 استناد 0 مرجع 0
نویسنده: 

BAHADOR NIMA | KARAMPOURI HAMID

اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    0
  • شماره: 

    16
تعامل: 
  • بازدید: 

    1575
  • دانلود: 

    0
چکیده: 

BACKGROUND AND AIM: HALOPHILES ARE A CLASS OF extremophile MICROORGANISMS, WHICH ARE ABLE TO GROW IN HIGH SALT CONCENTRATIONS. DEPENDING ON THE AMOUNT OF SALT REQUIRED FOR THE GROWTH THEY CLASSIFIED IN THE THREE GROUPS: SLIGHT HALOPHILES, MODERATELY HALOPHILES AND EXTREME HALOPHILES.ACCORDING TO THE TYPE OF MICROORGANISMS FOR TOLERANCE OF SALT CONCENTRATION THEY USE TWO PROCEDURE, SALT IN AND SOLUTE ADAPTATION. HALOPHILES ARE IMPORTANT MICROORGANISMS IN BIOTECHNOLOGY AND THEY PRODUCE HYDROLYSIS ENZYMES WHICH COULD BE USE IN INDUSTRY…..

آمار یکساله:  

بازدید 1575

دانلود 0
اطلاعات دوره: 
  • سال: 

    1398
  • دوره: 

    32
  • شماره: 

    2
  • صفحات: 

    247-257
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    242
  • دانلود: 

    85
چکیده: 

امروزه، بشر برای حل مشکلات صنایع دارویی، غذایی و شیمیایی، به سمت طبیعت و ترکیبات فعال زیستی روی آورده است. از جمله منابع این ترکیبات، متابولیتهای ثانویهی تولید شده توسط میکروارگانیسمهایی است که از مناطق بسیار سخت جداسازی شدهاند. هدف از این مطالعه، بررسی سویه های هالوتولرانت جدا شده از دریاچه حاج علی قلی خان با قابلیت های تولید متابولیت های ثانویه است. میکروارگانیسمهای نمکدوست و تحملکننده نمک مقاوم به نیکل، کادمیم، مس و کبالت از دریاچه حاجعلیقلیخان جدا شدند. توانایی ژنتیکی این جدایه ها برای تولید متابولیتهای ثانویه، با استفاده از تکثیر ژن های nrpS با آغازگرهای اختصاصی NS1/NS2، A3/A7 ارزیابی گردید. از غربالگری میکروارگانیسمهای دریاچه نمک به ترتیب 13%، 5/19%، 75/43 % و 7/3 % جدایهها از محیطهای کشت MGM، MH، SWN LNSWNو 62/20 % از جدایه ها از محیط بدون نمک نوترینت آگار بدست آمد. سنجش مقاومت به فلزات در جدایه های غربال شده از دریاچه نشان داد که بیشترین فراوانی جدایه ها در مقاومت به نیکل و حساسیت به فلز کادمیم است. نتایج تکثیر ژن های nrpS در جدایههای هالوتولرانت مقاوم به فلزات با دو جفت آغازگرهای اختصاصی 3 تا 7 قطعه DNA را نشان داد. حضور ژن nrpS در بین میکروارگانیسمهای نمک دوست نسبی و تحمل کننده نمک، ارتباط مستقیم بین مقاومت به فلزات سنگین و توانایی ژنتیکی تولید متابولیت های ثانویه را نشان می دهد.

آمار یکساله:  

بازدید 242

دانلود 85 استناد 0 مرجع 0
strs
اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    3
  • شماره: 

    SUPPL. (1)
  • صفحات: 

    260-260
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    33652
  • دانلود: 

    9450
چکیده: 

Since hypersaline environments are on the increase, halophilic organisms will prove even more valuable and provide significant opportunities for industrial biotechnology. Halophilic microorganisms produce stable enzymes capable of functioning under conditions such as high ionic concentration, presence of organic solvents, alkaline pH values, low oxygen availability, high or low temperatures, presence of heavy metals, and other toxic compounds. Laccases are blue copper-containing oxidases that catalyze the oxidation of a wide variety of organic and inorganic compounds to the corresponding reactive radicals, with the reduction of molecular oxygen to water. Laccases have been found in a wide range of organisms with different biological roles. Due to various applications in industrial scale, laccases from extremophile bacteria can be very interesting attractive. In the present study, an extracellular laccase producing halophilic bacterium was isolated from the Ajigol salty wetland and identified as Chromohalobacter sp. After inoculation fully grown purified strain, the isolate was cultivated in Luria-Bertani broth medium containing 3 M NaCl. After 3 days, the supernatant was precipitated. The precipitant was dialyzed and purified to an electrophoretically homogenous state by the affinity chromatography. The molecular mass of the purified enzyme was estimated to be about 60 KDa and demonstrated optimal activity at NaCl 3 M, pH 8.0 and 45oC. CuSO4 was the most effective inducer for laccase production. The enzyme was active up to 65oC and at pH range of 4-10 and was highly stable in the presence of various concentrations of LiCl and KCl.

آمار یکساله:  

بازدید 33652

دانلود 9450 استناد 0 مرجع 0
اطلاعات دوره: 
  • سال: 

    1396
  • دوره: 

    6
  • شماره: 

    22
  • صفحات: 

    45-57
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    541
  • دانلود: 

    95
چکیده: 

مقدمه: میکروارگانیسم های هالوفیل (نمک دوست) و هالوتولرانت (تحمل کننده نمک) گروهی از افراطی پسندها که قادر به رشد در محیط واجد نمک سدیم کلراید هستند و برای زندگی در محیط های شور تطابق یافته اند. وجود باکتری های نمک دوست در خاک های شور ازطریق حفظ چرخه غذایی، تجزیه مواد آلی و بهبود ساختمان و حاصلخیزی خاک شرایط خاک را بهبود می بخشد. مواد و روش ها: به منظور جداسازی باکتری های تحمل کننده شوری، از ریزوسفر گیاهان شورپسند، چهار منطقه بیابانی در استان گلستان نمونه گیری شد. برای بررسی میزان اکسترموفیل بودن جدایه ها، مقاومت آنها به شوری، خشکی، دما و pH بررسی شد و.همچنین صفات محرک رشد آنها نیز اندازه گیری گردید. نتایج: از چهل و پنج جدایه به دست آمده، سه جدایه (G3، G6 و G14) مقاومت 40 درصدی به شوری را نشان دادند. جدایه های G6 و G3 به ترتیب دارای قدرت حل کنندگی فسفات به میزان 301 و 201 میلی گرم بر لیتر بودند. جدایه G6 20.7 میکروگرم بر میلی لیتر اکسین تولید کرد. جدایه G14 و G6 در دمای 50 درجه سلسیوس، pH=10 و پتانسیل اسمزی -0.7 مگاپاسکال رشد داشتند، درحالی که جدایه G3 در دمای 50 درجه، در pH=7.5 و پتانسیل اسمزی -0.49 رشد داشتند. این سه سویه مربوط به جنس های باکتریایی Bacillus و Pseudomonas بودند.بحث و نتیجه گیری: در مطالعه حاضر جدایه های جداشده به دلیل رشد در غلظت های اشباع نمک و تحمل شرایط سخت محیطی، باکتری های تحمل کننده شوری و یا احتمالا نمک دوست است و پتانسیل استفاده در زمینه های مختلف بیوتکنولوژیکی ازجمله تولید آنزیم هایی صنعتی و کودهای بیولوژیکی برای اصلاح خاک های شور را دارد.

آمار یکساله:  

بازدید 541

دانلود 95 استناد 0 مرجع 0
اطلاعات دوره: 
  • سال: 

    2017
  • دوره: 

    9
  • شماره: 

    6
  • صفحات: 

    331-337
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    22545
  • دانلود: 

    16102
چکیده: 

Background and Objectives: In the present study, the Lut Desert, Iran was chosen as one of the hottest places in the world (with the recorded temperature of 70. 7° C during 2003-2009) to find out whether any heat-resistant microorganisms were present in the soil. Materials and Methods: The samples were collected from surface and depth of three identified places of Gandom Beryan in the Lut Desert. Chemical analysis and enumeration of the total bacteria, yeasts and molds were performed. Four selective culture media were employed to isolate the filamentous actinomycetes. The suspected colonies were further confirmed using PCR assay. Then the culture cell-free-supernatants (CFS) of isolates were used to investigate their antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Salmonella Typhimurium and Escherichia coli. Results: Chemical analysis of the samples included moisture (0. 2-0. 9%), ash (85-91%), organic materials (8. 3-14. 4%), pH (7. 59-9. 40) and electrical conductivity (380-2000 μ S/cm). The number of isolated bacteria and molds varied from 0-20 to 0-40 CFU/g, respectively. Number of Actinomycetes isolated from the soil samples were between 0-12. 2 CFU/g. Nine isolated colonies were identified as filamentous Actinomycetes. To determine the possibility of antimicrobial peptides, the CFS (cell-free supernatant) was firstly neutralized by NaOH and catalase. The results showed that none of the CFS of the isolates was effective against E. coli, S. Typhimurium and S. aureus, while the maximum inhibitory effect was investigated on B. cereus, which was 33. 1%± 1. 19% (mean ± SD). Conclusion: The results of the current study imply the presence of rare heat-resistant microorganisms in the soil of Gandom Beryan which may be further used to find out more about the function of natural bioactive compounds. Actinomycetes, as extremophile microorganisms, have shown the greatest genomic and metabolic diversity, as such the discovery of the novel Actinomycetes as a source of secondary metabolites is essential.

آمار یکساله:  

بازدید 22545

دانلود 16102 استناد 0 مرجع 0
اطلاعات دوره: 
  • سال: 

    2016
  • دوره: 

    6
  • شماره: 

    4
  • صفحات: 

    551-561
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    34953
  • دانلود: 

    25239
چکیده: 

Purpose: Robust pharmaceutical and industrial enzymes from extremophile microorganisms are main source of enzymes with tremendous stability under harsh conditions which make them potential tools for commercial and biotechnological applications.Methods: The genome of a Gram-positive halo-thermotolerant Bacillus sp. SL1, new isolate from Saline Lake, was investigated for the presence of genes coding for potentially pharmaceutical enzymes. We determined gene sequences for the enzymes laccase (CotA), l-asparaginase (ansA3, ansA1), glutamate-specific endopeptidase (blaSE), l-arabinose isomerase (araA2), endo-1, 4-b mannosidase (gmuG), glutaminase (glsA), pectate lyase (pelA), cellulase (bglC1), aldehyde dehydrogenase (ycbD) and allantoinases (pucH) in the genome of Bacillus sp. SL1.Results: Based on the DNA sequence alignment results, six of the studied enzymes of Bacillus sp. SL-1 showed 100% similarity at the nucleotide level to the same genes of B. licheniformis 14580 demonstrating extensive organizational relationship between these two strains. Despite high similarities between the B. licheniformis and Bacillus sp. SL-1 genomes, there are minor differences in the sequences of some enzyme. Approximately 30% of the enzyme sequences revealed more than 99% identity with some variations in nucleotides leading to amino acid substitution in protein sequences.Conclusion: Molecular characterization of this new isolate provides useful information regarding evolutionary relationship between B. subtilis and B. licheniformis species. Since, the most industrial processes are often performed in harsh conditions, enzymes from such halo-thermotolerant bacteria may provide economically and industrially appealing biocatalysts to be used under specific physicochemical situations in medical, pharmaceutical, chemical and other industries.

آمار یکساله:  

بازدید 34953

دانلود 25239 استناد 0 مرجع 0
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