Maryam Teimouri; Parisa Mohammadi; Adel Jalili; Roghaye Zarei
Abstract
The aim of this study was to compare the effect of primers in evaluating soil bacterial community structure. For this purpose, soil samples were taken from cold and warm area which grazed (disturbed) or not grazed (undisturbed) in spring and autumn. Microbial DNA was extracted and sequenced after amplification ...
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The aim of this study was to compare the effect of primers in evaluating soil bacterial community structure. For this purpose, soil samples were taken from cold and warm area which grazed (disturbed) or not grazed (undisturbed) in spring and autumn. Microbial DNA was extracted and sequenced after amplification by two primers which amplify V1-V3 and V4-V5 area of 16S rRNA. Next generation sequencing data were analyzed by QIME to determine bacterial community structure. Results showed the effect of area, grazing and season on bacterial community structure. NGS data analysis showed that primers which amplified V4-V5 area identified more bacteria (97.9%) in compared to V1-V3 primers (90.4%). V1-V3 primers had better efficiency to identify Proteobacteria (37.85%) in compared to V4-V5 which identified more Actinobacteria (33.6%). In addition, V4-V5 primers identified more bacteria in class, family and genus taxonomic groups in compared to V1-V3 primer. Although V4-V5 primer had better efficiency in bacteria identification, it is recommended to use both primers to evaluate precisely bacterial community structure.
Parisa Mohammadi; Nora javanmardy; Parisa Tajer Mohammad Ghazvini
Abstract
Today bioremediation by microalga is an effective method to remove radionuclides and heavy metals from wastewater. Bioremediation of radionuclides and heavy metals is an efficient method of treating heavy metal contaminated effluents. In this study, the bioremediation of uranium from aqueous solutions ...
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Today bioremediation by microalga is an effective method to remove radionuclides and heavy metals from wastewater. Bioremediation of radionuclides and heavy metals is an efficient method of treating heavy metal contaminated effluents. In this study, the bioremediation of uranium from aqueous solutions was evaluated using live microalgae Chlorella vulgaris in a batch system. The Plackett-Burman method by Minitab statistical software was used to screen for effective factors such as initial uranium concentration, temperature, time, pH and amount of biomass on the removal of uranium by C. vulgaris. The results showed that the initial uranium concentration and pH factors were statistically effective by software. Optimization of effective factors in uranium bioremediation was evaluated by the response surface methodology (RSM). To determine the main effects and interaction of factors affecting uranium removal by C. vulgaris, central composite design (CCD) was used. The experimental data were then processed and the equation was evaluated to match the experimental data, and then the optimal removal values were determined. Finally, the results showed that C. vulgaris in optimal conditions proposed by Design-Expert software can remove 99.63% of existing uranium from aqueous solutions containing 7.1 mg / l uranium with pH 4.3.
Faezeh Hamzekhani; Parisa Mohammadi; Azra Saboora
Abstract
Lichens produce high diversity of metabolites and they have different biological activities including antibacterial, antifungal, antiviral, anti-inflammatory and the cytotoxic effects. In this study, the impact of antimicrobial substances of lichens were studied. For this purpose, the lichens of northern ...
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Lichens produce high diversity of metabolites and they have different biological activities including antibacterial, antifungal, antiviral, anti-inflammatory and the cytotoxic effects. In this study, the impact of antimicrobial substances of lichens were studied. For this purpose, the lichens of northern forests around Babol city was collected and via the morphological and microscopic characteristics, biochemical and molecular methods were identified. Then, ethanol extracts of lichens were prepared. Antimicrobial effects of extracts was assayed using the diffusion agar method and the determination of minimum inhibitory concentration against five bacteria, Bacillus cereus, Xanthomonas campestris, Escherichia coli, Staphylococus aureus and Pseudomonas aeruginosa. The studies showed that the extract of Leptogium saturninum, Ramalina peruviana, Punctelia borreri were effective against X. campestris، S. aureus. However, in the case of Bacillus cereus and E.coli only the extract of R. peruviana was effective. Furthermore, measuring the diameter of zone inhibition and MIC against three clinical Candida albicans, Candida tropicalis, and Candida glabrat showed that the extracts of Leptogium saturninum, Ramalina peruviana were effective on all the strains. However the extract of Punktelia subrodecta was effective only on C.albicans. The substance of lichens, which assayed by biochemical tests showed that due to the presence of phenolic compounds, lichens show high antimicrobial properties. It should be carried out the antimicrobial experiments on a wide range of environmental and pathogenic microorganisms.
Aida Hamidkhani; Parisa Mohammadi; Ezzat Asgarani; Maryam Yoseffi
Abstract
Candida species are the most common cause of fungal infections. Early identification of Candida species is necessary for effective antifungal therapy and can also facilitate control of hospital infections. Identification of Candida species by conventional methods is time-consuming with low sensitivity, ...
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Candida species are the most common cause of fungal infections. Early identification of Candida species is necessary for effective antifungal therapy and can also facilitate control of hospital infections. Identification of Candida species by conventional methods is time-consuming with low sensitivity, but molecular approaches have provided an alternative way for their early diagnosis. Considering different molecular approaches limitation for diagnosis of Candida species, in this study PCR-DGGE was evaluated for detection of five different pathogenic Candida species including C.glabrata, C.tropicalis, C.albicans, C.orthopsilosis and C.parapsilosis. ITS2 region was amplified using ITS3-GC and ITS4 primer set and the amplified fragments were used in DGGE. The results showed that DGGE is capable of detection of Candida species being analyzed.
Marzieh Mtin far; Parisa Mohammadi; Mahnaz Gholi pour shahraki; Mostafa Norouzi
Abstract
Pasargadae set of ancient structures remaining from the Achaemenid impire are located in Fars province, Iran. Tomb of Cyrus the Great, which is made of limestone placed in the southern part of this area. Like any other stone, the building has been influenced by physico-chemical and biological factors. ...
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Pasargadae set of ancient structures remaining from the Achaemenid impire are located in Fars province, Iran. Tomb of Cyrus the Great, which is made of limestone placed in the southern part of this area. Like any other stone, the building has been influenced by physico-chemical and biological factors. Biodeterioration of materials is an irreversible process which materials and equipment under the influence of the micro and macroorganisms are degraded and causes massive economic losses. Almost all microorganisms are in the destructive biofilm form on the external surfaces of the monuments and phototrophic microorganisms preparing suitable condition for the growth of other organisms. The effects of these organisms are particularly important in the context of biodeterioration. BG-11, MKM, BBM medium was used for isolation of phototrophs. Stereomicroscope and scanning electron microscope (SEM) was done to observe the biological structures and the pattern of deteriorating alteration on the surface of the substratum. To identify the phototrophic populations, cultivation method was used. During this study, several species of microorganisms, including algae and cyanobacteria in biofilm structure, were isolated. Most of these species were sampled from the inside of tomb that displays more suitable conditions for phototrophic growth. Stereomicroscopic observation and SEM images revealed that microorganisms were better located within the cavities of the stone, where the intensity of light is optimum for phototroph growth. In this study, the most frequent type of biodeteriorant algae belong to Trebouxia sp., Chlorococcum sp. and Trentepohlia sp. For cyanobacteria, the genus of Chroococcus sp., Oscillatoria sp., Microcystis sp., Aphanothece sp., andLyngbya sp. were dominant cyanobacteria. The first step in eliminating orcontrolling the growth of deteriorating microorganisms is their isolation andidentification. Thus, the present study was carried out to isolate and identifyinvolved microorganisms. Further investigation should be done to find the bestmethod to clean the surfaces of the stone.
