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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Biodegradation,Naphthalene,Degrading bacteria,Gol Gohar Mine
- چکیده:
- چکیده انگلیسی: Naphthalene is an ubiquitous pollutant of the environment and the biodegradation of this pollutant has been receiving constant scientific consideration. The aim of this study was to isolate and identify bacteria that could degrade naphthalene from three regions of the Gol Gohar Mine at Sirjan, Iran. In this study, the total naphthalene degrading bacteria were quantified with the most probable number (MPN) and the colony forming unit (CFU) methods. The results showed that most of the bacteria communities capable of degrading naphthalene aggregated in the (WG) site. Among 22 isolated bacteria, seven strains were selected for their ability to grow at higher concentrations of naphthalene (300 and 400 mg/l) and biochemical characteristics. Finally, two strains named isolates 72N and 79N were selected for analysis of the 16S rRNA sequences. Strain 72N was identified as Pseudomonas fluorescens AHB72N and strain 79N was shown to be related to Pseudomonas gessardii AHB79N. The results of biodegradation tests showed that these two strains could degrade 600 mg/l naphthalene in 7 days. The results indicated that strain 79N showed higher potential for removing naphthalene than strain 72N. Practical application of bacterial strains for the degradation of naphthalene from the industrial zones opens interesting prospects. The results of this study provide useful information in evaluating naphthalene degraders isolated from wastewater and industrial sites.
- انتشار مقاله: 30-03-1395
- نویسندگان: Mehdi Hassanshahian,Moslem Abarian,Arastoo Badoei-Dalfard
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Biological Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Purification,Characterization,Stability,activity,Phytase
- چکیده:
- چکیده انگلیسی: Microbial phytases were applied mainly to animal and human foodstuffs in order to improve
mineral bioavailability and food processing. In addition, phytases have potential
biotechnological application in various other fields, such as environmental protection,
aquaculture and agriculture. Bacillus sp. DM12, an isolate from a hot spring, produces phytase,
which catalyzes the hydrolysis of phytic acid into myo-inositol and inorganic phosphates.
Phytase from Bacillus sp. DM12 was purified using ammonium sulfate precipitation and
dialysis, followed by anion exchange and gel filtration chromatography. Molecular weight of
the purified phytase was estimated to be 28 kDa by SDS-PAGE. Km and Vmax values for sodium
phytate were 0.177 mM and 1.126 μmol/min, respectively. The optimum temperature for
phytase activity was found to be 50°C. The enzyme retained over 75% of its activity over a
temperature range of 30 to 80°C. The highest phytase activity was observed at pH 4.5 and a
decline of enzyme activity was observed on both sides of pH optimum. The enzyme was stable
over the pH range of 3.0 to 6.0. The enzyme retained over 80% of its activity in the presence of
5 mM metal ions except CaCl2. It is also indicated that the enzyme retained over 65% of its
activity over a 5 mM metal ions. These properties suggest that this phytase is a suitable enzyme
for the hydrolysis of phytic acid and phytates in food and feed processing industries.
- انتشار مقاله: 19-09-1393
- نویسندگان: Maryam Parhamfar,Arastoo Badoei-Dalfard,Mouj Khaleghi,Mehdi Hassanshahian
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Kerman University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Antimicrobial activity,Marine environment,Biofilm,Sponge,Sea Anemone
- چکیده:
- چکیده انگلیسی: Background: Sponges and sea anemones do not have specialized defense organs. Instead, they rival harmful microorganisms by producing certain compounds. These compounds can also be useful against some human pathogens. This study aimed to investigate the antimicrobial effects of bioactive products from these marine animals. Methods: Two species of sea anemone (Zoanthus sansibaricus and Cerianthus lloydii) and one species of sponge (Callyspongia sp.) were collected at the Persian Gulf. The active metabolites of these two marine animals were extracted by methanol and dichloromethane solvents. The antimicrobial activity of each extract was performed against six human pathogenic bacteria including: Pseudomonas aeruginosa, Acinetobacter baumannii, Bacillus cereus, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus, using disk diffusion and agar well plate methods. The MIC and MBC were determined. The inhibitory effect of these extracts on biofilm formation was also studied. Results: The effect of sponge extracts against planktonic forms of bacteria showed that the most sensitive bacteria to Callyspongia sp. extracts were K. pneumoniae and S. aureus. However, C. lloydii did not have any inhibitory effect on K. pneumoniae. The results of this study confirmed that both sponge and sea anemones extracts had sufficient effects against biofilm formation of pathogenic bacteria.However, Callyspongia sp. extracts had the lowest inhibitory effect against biofilm formation of P. aeruginosa. The highest inhibitory effect was observed on biofilm formation of K. pneumoniae. Conclusion:The Callyspongia sp sponge extract (Dichloromethane: Methanol) has an excellent antimicrobial effect against six pathogenic bacteria in planktonic and biofilm forms. There was a direct correlation between the increase in the concentration of sea anemones extracts and the inhibitory effect of biofilm formation.
- انتشار مقاله: 07-09-1397
- نویسندگان: Homa Hamayeli,Mehdi Hassanshahian,Mahasti Mohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Kerman University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Medicinal plants,Antibacterial activity,Antibiotic resistant,Biofilm
- چکیده:
- چکیده انگلیسی: Background: Microbial biofilms are responsible for many human infections and increase of antibiotic resistant bacteria. Therefore, finding an efficient way to prevent infection and biofilm formation of bacteria is essential. Medicinal plants are among suitable candidates to inhibit biofilm formation of bacteria. The aim of this study was to evaluate the antimicrobial effects of Trachyspermum, Thymus and Pistachio (T.T.P) combined extracts (methanolic and ethanolic) against six pathogenic bacteria in planktonic and biofilm forms. Methods: The antibacterial activities of T.T.P combined extracts against planktonic form of pathogenic bacteria were evaluated by disc diffusion and macro-broth dilution methods. Also, anti-biofilm activity of the combined extracts was evaluated by microtiter plate method. Results: The results of disc diffusion analysis (MBC and MIC) showed that both methanolic and ethanolic extracts of T.T.P combined extracts were efficient for inhibition of planktonic forms of bacteria, although ethanol extract was more effective compared to the methanolic extract. The T.T.P combined extracts had inhibitory effect against biofilm formation of pathogenic bacteria. Also, these extracts efficiently demolished biofilm formation and prevent metabolic activity of bacteria in biofilm structures. The concentration of each extract had a direct relationship with its inhibitory effect. The maximum inhibitory effects of T.T.P combined extracts on biofilm formation, demolish of biofilm structure and inhibition of the metabolic activity of bacteria in the biofilm were 95.3% for P. aeruginosa, 97.2% for P. aeruginosa and 81.16% for E. coli. Conclusion: The results of this research demonstrated that T.T.P combined extracts can be used as an alternative component with inhibitory effect against pathogenic bacteria in planktonic and biofilm forms.
- انتشار مقاله: 12-06-1396
- نویسندگان: Fatemeh Masoumipour,Mehdi Hassanshahian,Tayebeh Jafarinasab
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Kerman University of Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Biofilm,antimicrobial effect,Drug Resistant,Eucalyptus camaldulensis
- چکیده:
- چکیده انگلیسی: Background & Aims: Microorganisms are protected from antimicrobial agents when placed in biofilm structure. Biofilm-producing microorganisms are responsible for many problems in industry and medicine; therefore, it is essential to find new techniques for removing and inhibiting biofilms. This study aimed to examine the antimicrobial effect of Eucalyptus camaldulensis alcoholic extracts against planktonic form and biofilm of six bacteria including Staphylococcusaureus aureus, Bacillus cereus, Streptococcus pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae. Methods: Antimicrobial activities of the plant extracts against the planktonic form of bacteria were evaluated using disc diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined using a macrobroth dilution technique. Anti-biofilm effects were assessed using microtiter plate method. Results: The results of this study confirmed the strong ability of E. camaldulensis extracts against the biofilm of tested bacteria and their free-living forms. Ethanolic extracts were more effective in inhibiting planktonic bacterial growth than methanolic extracts. Anti-biofilm effects of plant extracts were associated with the solvent and extract concentration. Eucalyptus camaldulensis methanol extract of 20 mg/ml concentration was the most efficient in the inhibition of biofilm formation of Staphylococcus aureus (84.42%). These extracts had the ability to remove more than 50% of stabilized biofilms. In Klebsiella pneumonia, however, only a 29.20% eradication of biofilms was observed. The highest decrease in methabolic activity was observed in Streptococcus pneumoniae biofilms (82.13%) treated with 20 mg/ml ethanolic extract. Conclusion: In this study, the antimicrobial activity of Eucalyptus camaldulensis extracts against the selected microorganisms was demonstrated. Thus, these extracts are recommended as a suitable option against the selected isolates
- انتشار مقاله: 24-04-1395
- نویسندگان: Zeynab Mohsenipour,Mehdi Hassanshahian,Mohammad Moradi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Herbal Drugs
- نوع مقاله: Journal Article
- کلمات کلیدی: essential oil,Antimicrobial activity,Minimum inhibitory concentration,Zataria multiflora,Acinetobacter baumannii,Minimum bacterial concentration
- چکیده: مقدمه و هدف: هدف از این مطالعه بررسی فعالیت ضد میکروبی اسانس آویشن شیرازی بر روی اسینتو باکتر بومانی جدا شده از نمونه های بالینی است. روش تحقیق: دوازده سویه اسینتو باکتر بومانی از بیمارستان های شهرستان زابل جداسازی شد. اسانس آویشن شیرازی با استفاده از دستگاه کلونجر بدست آمد، در نهایت حداقل غلظت مهار کنندگی و حداقل غلظت کشندگی اسانس در برابر باکتریهای ذکرشده با روش میکرودایلوشن تعیین گردید. نتایج و بحث: نتایج حاصل از این مطالعه نشان داد که کمترین غلظت مهار کنندگی در برابر باکتری ها برابر با 31/0 میلی گرم بر میلی لیتر است و تنها یک سویه از باکتری در این غلظت مهار شده است. بیشترین غلظت مهار کننندگی برابر با 10 میلی گرم بر میلی لیتر بوده و یک سویه نیز در این غلظت مهار شده است. توصیه کاربردی و صنعتی: نتایج نشان داد که اسانس با افزایش غلظت اثرات ضد میکروبی آن افزایش پیدا می کند، اسانس آویشن فعالیت ضد میکروبی خوبی حتی در غلظت های پایین از خود نشان داد. با کاربرد اسانس آویشن شیرازی علیه باکتری های بیماریزا می توان به یک ماده ضد میکروبی خوب بدون اثر جانبی دست پیدا کرد.
- چکیده انگلیسی: Background & Aim: The aim of this study was to investigate the antimicrobial effects of Zataria multiflora against some Acinetobacter baumannii strains isolated from clinical samples. Experimental: Twelve strains of Acinetobacter baumannii were isolated from referred patients in Zabol hospital. Essential oil of Zataria multifloraspecies was extracted using Clevenger device. Minimum Inhibitory Concentration (MIC) and Minimum Bacterial Concentration (MBC) of essential oil on mentioned bacteria were determined using micro dilution broth method at six different concentrations. Results: The results of this study showed that the lowest inhibitory concentration of essential oil against bacteria was 0.31 mg/ml, and only one strain of bacteria was inhibited. However, the highest inhibitory concentration was estimated 10 mg/ml. Recommended applications/industries: The results showed that the antimicrobial effects increased with increasing in essential oil concentration and the essence showed good antimicrobial activity even at low concentrations. With the use of essential oil of Zataria multiflora against bacterial pathogens, a good antimicrobial agent can be obtained without any side effects.
- انتشار مقاله: 18-07-1396
- نویسندگان: Khadije Rezaie Keikhaie,Gholamreza Bagheri,Mehdi Hassanshahian,Saeide Saeidi
- مشاهده
- جایگاه : پژوهشی
- مجله: International Aquatic Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Antimicrobial activity,Biofilm,Stichodactyla haddoni,Bioactive metabolites,Aliphatic compounds
- چکیده:
- چکیده انگلیسی: Sea anemones produce many biologically active compounds including neurotoxins, pore-forming toxins, phospholipases and proteinase inhibitors. The Persian Gulf is an unexplored environment and maybe a rich source of marine natural products. The aim of this study is screening and identification of bioactive metabolites from Stichodactyla haddoni (Haddon’s sea anemone) collected at the Persian Gulf. The crude extract of the sea anemone (tentacle, disc and total body) was obtained by methanol solvent. The antibacterial assays were carried out by the disc diffusion method. The antibiofilm activity (biofilm formation, biofilm destruction and reduction of metabolic activity) of the sea anemone extracts was evaluated by microtiter plate method. The bioactive compounds were identified by GC–MS analysis. Data showed that the best antibacterial effect (relate to P. aeruginosa) is obtained from extracts of “total body” section. Values of minimum inhibitory concentration and minimum bactericidal concentration show that the maximum antibacterial activity takes place at 10–20 mg/ml concentration. Three parts of sea anemone exhibit different inhibition against biofilm of bacteria, in particular, inhibition of biofilm observed by the tentacle, disc and total body against P. aeruginosa, K. pneumonia and A. baumannii, respectively. Biofilm of P. aeruginosa was the most sensitive and the biofilm of B. cereus was the most resistant structure between all pathogenic bacteria. The best reduction in the metabolic activity was observed in P. aeruginosa and K. pneumonia among tested bacteria. Aliphatic compounds were predominant bioactive metabolites in this sea anemone. The marine animal and especially sea anemone produce useful bioactive compounds that can be used to prevent bacterial biofilm; application of bioactive materials, reported in this study, can be proposed for future studies.
- انتشار مقاله: 27-12-1398
- نویسندگان: Homa Hamayeli,Mehdi Hassanshahian,Majid Askari Hesni
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Bacteria,Hexadecane,Cell hydrophobicity
- چکیده:
- چکیده انگلیسی: Some properties of compounds in degrading bacteria are required for biodegradation of contaminants to higher performance. Those strains which have a high percentage of these features are more effective at biodegradation. The present experiments were designed to measure these parameters. In this study, measurement of cell surface hydrophobic-degrading bacteria was designed which oil was separated from contaminated soils. Hydrophobic cell surface helps to binding bacteria to hydrocarbons which most of them are hydrophobic. In this experiment, the optical density was measured before and after addition of hexadecane at 600 nm. The highest percentage of Cell surface hydrophobicity (BATH%) of strains were 27,32,24 and 29 by Rhodococcus, Achromobacter, Stenotrophomonas and Tsukamurella, respectively and the growths of hydrocarbon degrading bacteria in hexadecane (1%) contain 1.9, 1.85, 1.4 and 1.12, respectively. It shows that whit increasing the amount of hydrophobic cell levels; consequently, the amount of hexadecane degradation will increase.
- انتشار مقاله: 09-05-1393
- نویسندگان: Hamid Tebyanian,Seyed Hanif Mirhosseiny,Omidreza Sarrafi,Ehsan Aliakbari,Mehdi Hassanshahian
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Advanced Biological and Biomedical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Bacteria,Bioremediation,Hydrocarbon,Crud oil,Alkan
- چکیده:
- چکیده انگلیسی: Petroleum hydrocarbons are important energy resources used by industry and in our daily life, whose production contributes highly to environmental pollution. To control such risk, bioremediation constitutes an environmentally friendly alternative technology that has been established and applied. It constitutes the primary mechanism for the elimination of hydrocarbons from contaminated sites by natural existing populations of microorganisms. Petroleum (or crude oil) is a complex mixture of hydrocarbons. Annually, millions of tons of crude petroleum oil enter the marine environment from either natural or anthropogenic sources. Hydrocarbon-degrading bacteria (HDB) are able to assimilate and metabolize hydrocarbons present in petroleum. Crude oil pollution constitutes a temporary condition of carbon excess coupled to a limited availability of nitrogen that prompts marine oil-degrading bacteria to accumulate storage compounds. This review focuses on the role and distribution in the environment of degradation bacteria and their (potential) applications in bioremediation and biocatalysis. Bacteria play an important role in the microbial degradation of oil, chlorinated hydrocarbons, fuel additives, and many other compounds. Environmental studies demonstrate the abundance of alkane degraders and have lead to the identification of many new species, including some that are (near) obligate alkanotrophs. Bioremediation is being increasingly seen as an affective, environmentally friendly treatment for contaminated shorelines from marine oil spills. Oil bioremediation is limited by the availability of nitrogen and phosphorous which are needed by the bacteria and are not present in sufficient amounts for the biodegradation of the spilled hydrocarbons.
- انتشار مقاله: 09-05-1393
- نویسندگان: Ehsan Aliakbari,Hamid Tebyanian,Mehdi Hassanshahian,Ashraf Kariminik
- مشاهده
- جایگاه : پژوهشی
- مجله: Current Medical Mycology
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,Extract,antimicrobial effect,Echinophora platyloba,Rosmarinus officinalis
- چکیده:
- چکیده انگلیسی: Abstract
Background and Purpose: In traditional medicine, herbal products still remain the principal source of pharmaceutical
agents. The present study aimed to investigate the antifungal effects of Echinophora platyloba and Rosmarinus officinalis
extracts on C. albicans species.
Materials and Methods: The aqueous and ethanolic leaf extracts of E. platyloba and R. officinalis, collected from the
mountainous regions of Iran, were screened in terms of antimicrobial activity against C. albicans strains, using the agar
well diffusion method. The minimum inhibitory concentration was determined by the microtitration technique.
Results: Overall, the results showed that the leaf extracts of E. platyloba and R. officinalis had strong antimicrobial
activities. Also, based on the findings, R. officinalis leaf extracts exhibited higher antimicrobial activity. The ethanolic
leaf extracts of E. platyloba and R. officinalis showed good antimicrobial activity against C. albicans strains. However,
the aqueous extracts did not show any major activities against the tested C. albicans strains. On the other hand, the
ethanolic extracts exhibited major antimicrobial properties against C. albicans strains. The highest minimum inhibitory
concentration was reported in E. platyloba leaf extracts.
Conclusion: The present results indicated some advantages of E. platyloba and R. officinalis leaf extracts, which could be
applied for the treatment of microbial infections- انتشار مقاله: 18-04-1398
- نویسندگان: Zahra Sepehri,Fereshteh Javadian,Davoud Khammari,Mehdi Hassanshahian
- مشاهده