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In recent decades, human actions aimed at maintaining dominance over the earth's natural resources have endangered the ecological balance. The irreparable damage caused by oil pollution not only impacts the environment but also affects the economy and the health of living organisms. Therefore, in addition to preventive measures, it is crucial to focus on techniques for removing this type of pollution. Bioremediation, which involves the use of microorganisms like bacteria and fungi to eliminate, decompose, or reduce pollution, offers eco-friendly and cost-effective advantages. While organisms from various domains can play a role in bioremediation, fungi stand out as promising candidates. Their metabolic abilities enable them to breakdown complex molecules, making them highly effective in degrading stubborn organic matter in nature. Fungi, often referred to as mycoremediators, have been more extensively studied for bioremediation in terrestrial ecosystems compared to aquatic environments. This review explores the research conducted on fungi and bioremediation, summarizing findings and analyzing the progress in this field from the past to the present through bibliometric analysis. The results indicate that most studies concentrate on fungi isolated from soil, with Aspergillus, Penicillium, Fusarium strains being frequently reported. China, Iran, and Nigeria have published the most documents on this subject in the Scopus database. Utilizing a consortium of microorganisms is likely to yield better results than using a single strain. Overall, the use of fungi in bioremediation shows promise due to their specific metabolic characteristics. [ABSTRACT FROM AUTHOR]

Crude oil pollution can decrease the biodiversity in the marine environment. The Persian Gulf in Iran is an ecosystem rich in marine organisms that can effectively degrade crude oil. This study aimed to screen bacterial strains to degrade crude oil from the intestinal microbial flora of Mudskippers fish from the Persian Gulf. The identification of collected fish samples distinguished four diverse genera. Periophthalmus waltoni was the most common. Next, biochemical and molecular identification of isolated bacteria was performed. Some biochemical tests, such as catalase, oxidase, and motility, were done. Molecular identification was performed by polymerase chain reaction using general primers. Finally, the ability of bacterial isolates to degrade crude oil was investigated using spectrophotometric, gravimetric, gas chromatography, and FTIR methods. Bacteria identified in this study include Marinobacter hydrocarbonoclasticus, Pseudomonas aestusnigri, Thalassospira permensis, Microbacterium esteraromaticu, Oceanimonas sp, Halomonas Salaria, Halomonas beimenensis, Cobetia marina, Tenacibaculum discolor and Shewanella chilikensis. Halomonas salaria had the highest growth rate (OD= 1.6) and crude oil degradation (90%) among the studied strains. The results of our studies on five strains of T. permensis, S. chilikensis, M. hydrocarbonoclasticus, and Oceanimonas in concentrations of 1, 2.5, 4, 5.5, and 7 g/l crude oil show that with increasing concentration, crude oil reduces the ability of the strains to degradation (decrease degradation from 90 % to 20 %). Other studies have been conducted to recognize fish as an indicator of oil pollution. Still, the results of this research confirmed that crude oil pollution decreases the biodiversity in the intestinal microbial flora of these fish. The isolated bacteria can degrade crude oil and help degrade this pollution in aquatic ecosystems. By applying these bacteria, crude oil pollution in the Persian Gulf can be better managed and decreased. [ABSTRACT FROM AUTHOR]

The marine environment is a rich source of microorganisms producing bioactive compounds, like biosurfactant-producing bacteria that exhibit unique characteristics and functionalities. In this study, we examined glycolipid biosurfactants produced by bacteria that live commensally with marine organisms. We isolated a biosurfactant-producing strain identified as Cobetia marina strain F1, which displayed high hemolytic activity (27 mm), oil spreading ability (4 mm), emulsification index (40%), and decreasing surface tension to 31.3 (mN·m−1). Fourier transform infrared (FT-IR) spectroscopy revealed the glycolipid composition of the biosurfactant. Furthermore, elemental analysis utilizing CHNS and energy-dispersive X-ray spectroscopy (EDS) confirmed the biosurfactant contained carbon, hydrogen, nitrogen, sulfur, chlorine, potassium, oxygen, and additional elements. The critical micelle concentration (CMC) of the crude biosurfactant was determined to be 350 mg·L−1, at which concentration, a decrease in surface tension was observed when the biosurfactant was dissolved in distilled water. Given the presence of impurities in the biosurfactant composition, this observed CMC is considered acceptable. Furthermore, the biosurfactant exhibited significant antimicrobial activity against both Gram-positive and Gram-negative bacterial strains, with the largest zone of inhibition (ZOI) of 27 mm against Pseudomonas aeruginosa. This demonstrates the potential of the biosurfactant to serve as an alternative to novel antibiotic agents. The biosurfactant exhibited considerable inhibition of biofilm formation, disruption of preformed biofilms, and reduced enzymatic activity in bacterial cells following treatment. Moreover, the combination of the biosurfactant and F1 bacterial strain enhanced the degradation of crude oil by 86%, indicating its potential application in environmental remediation. These findings highlight the importance of investigating commensal strains capable to produce biosurfactants for applications in hydrocarbon remediation, overcoming antibiotic resistance, and biofilm disruption. [ABSTRACT FROM AUTHOR]

Phenols exhibit high solubility in water, leading to their potential to contaminate significant volumes of freshwater, wastewater, groundwater, oceans, and soil. The primary objective of this study is to isolate and identify bacterial and yeast isolates with optimal phenol degradation capabilities from Persian Gulf. Sea water and sediment samples were collected to isolate bacterial and yeast isolates, which were then evaluated for their ability to degrade phenol both in their single-cell form and when encapsulated in chitosan and alginate. The phenol-degrading strains were quantified using colony-forming unit (CFU) and most probable number (MPN) methods. The most promising microorganisms were selected and identified using phenotypic and polymerase chain reaction techniques. The selected isolates were immobilized in alginate and chitosan carriers, and their bioremediation potential was assessed at different phenol concentrations. The removal of phenol by the isolates was confirmed using Gas Chromatography. Through molecular techniques, Acinetobacter calcoaceticus K5 and Candida tropicalis YM2 were identified as the most efficient phenol-degrading strains. Acinetobacter calcoaceticus K5 exhibited the highest growth at phenol concentrations of 200 and 300 ppm, while Candida tropicalis YM2 showed optimal growth at a concentration of 700 pp. In case of Acinetobacter calcoaceticus, chitosan immobilization and a phenol concentration of 500 ppm proved to be the best conditions for phenol bioremediation. In the case of Candida tropicalis YM2, the highest percentage of phenol removal was achieved using the chitosan carrier at a concentration of 1000 ppm. Comparing the immobilized strains to their free counterparts, it was observed that the stabilized bacteria exhibited greater phenol removal efficiency, particularly at a concentration of 500 ppm, with a significant difference between the two conditions. This study demonstrates that the novel strains Acinetobacter calcoaceticus K5 and Candida tropicalis YM2 are efficient strains for the bioremediation of various phenol-contaminated seawater and this is the first report to show such rapid phenol degradation by these organisms isolated from sediment and seawater samples collected from Persian Gulf. [ABSTRACT FROM AUTHOR]

The Persian Gulf is a transit point for a lot of crude oil at the international level. The purpose of this research is to compare two methods of biostimulation and bioaugmentation for degradation of sediments contaminated with crude oil in the Persian Gulf. In this research, six types of microcosms were designed (sediments of Khark Island). Some indicators, such as the quantity of marine bacteria, enzyme activity (catalase, polyphenol oxidase, and dehydrogenase), biodiversity indices, and the percentage of crude oil degradation were analyzed during different days (0, 20, 40, 60, 80, 100 and 120). The results of this research showed that the highest quantity of heterotrophic and crude oil-degrading bacteria to the sixth microcosm (stimulation–bioaugmentation), a combination of two methods bioaugmentation and biostimulation (3.9 × 106 CFU g−1). After crude oil pollution, the activity of catalase and polyphenol oxidase increased, and the dehydrogenase enzyme decreased. Bioaugmentation microcosm has the highest activity of enzymes among all studied microcosms. Predominant bacteria in each microcosm belonged to Cellulosimicrobium, Shewanella, Alcanivorax, and Cobetia. The highest degradation of crude oil is related to the stimulation–bioaugmentation microcosm. The statistical results of this research proved that there is a significant relationship between the type of method chosen for biodegradation with the sampling time and the quantity of marine bacteria. The results of this research confirm that crude oil pollution in the Persian Gulf sediments can be reduced by choosing the proper bioremediation method. [ABSTRACT FROM AUTHOR]

Makran Sea and its coastal areas are one of the richest marine ecosystems in the world. The primary purpose of this research was to study Naphthalene-degrading bacteria in some coastal areas of Makran Sea. Four coastal areas of Makran Sea were selected and marine samples were taken from each. Naphthalene-degrading bacteria were enriched in ONR medium in the shaker incubator for seven days with Naphthalene as the sole carbon source. This process was carried out in two separate passages. Some screening analyses were conducted for the selection of the best Naphthalene-degrading strains such as growth assay (OD600 nm), Naphthalene-degradation (GC), cell surface hydrophobicity (BATH), and emulsion production (E24). The predominant strain in Naphthalene-degradation was identified by molecular method. The results of this study showed that the quantity of bacteria present in different regions of Makran Sea varies. An example of this was the highest quantity of Naphthalene-degrading bacteria which were observed in Jask Port, however, the level of heterotrophic bacteria was the highest in Konark Station in comparison to other areas. In this research 65 Naphthalene-degrading bacteria were isolated from collected marine samples. Screening analysis confirmed that 9 strains were more efficient in Naphthalene-degradation and these strains were selected for further study. The best Naphthalene degrader isolate in this study was HS-2 strain, which according to molecular identification results belongs to Shewanella alga. This strain was an emulsifier producer (E24: 88%), and had high cell surface hydrophobicity (BATH: 36%) and was able to degrade Naphthalene in 3000 ppm concentration (70.8%). The results of this research confirmed that Makran marine ecosystem has effective bacteria in the degradation of Polycyclic Aromatic Compounds (PAH). By using these bacteria in the field, it is possible to reduce aromatic pollution in these coastal areas. [ABSTRACT FROM AUTHOR]

The Persian Gulf is the most critical aquatic environment in the world. The relationship between marine animals and degrading bacteria not well understand. The purpose of this investigation is the description of symbiont crude oil-degrading bacteria in some sponges in the Persian Gulf. Marine sponges were collected from four stations at the Persian Gulf. Symbiont crude oil-degrading bacteria were isolated from marine sponges by enrichment in ONR7a medium after four subcultures. The isolated bacteria were identified by biochemical and molecular methods. The degradation of crude oil was determined by spectrophotometric, gravimetric, and GC-FID methods for each strain. In this study, 38 crude oil-degrading bacteria were isolated from 8 sponge samples. The efficient strains that had the highest crude oil degradation belonged to the genus Cellulosimicrobium, Shewanella, Alcanivorax and Cobetia. The GC-FID analysis confirmed that the strains IAUK3532, IAUK3537 and IAUK3519 exhibit maximum degradation of crude oil (respectively, 94.5%, 88.13% and 85%). It is observed that when the concentration of crude oil increased, the degradation decreased. It can be concluded from these results that the microbes that coexist in the sponges located at the Persian Gulf can degrade crude oil. These symbionts crude oil-degrading bacteria can be applied to decrease the oil pollution in the Persian Gulf. Also, the symbiotic relationship between sponges and crude oil-degrading bacteria increases sponge survival and contributes to the development of their colonies in the Persian Gulf. [ABSTRACT FROM AUTHOR]

Byline: Hossein Ghanavati (Department of Biology, Faculty of Science, Isfahan University, Isfahan, Iran, ghanavatih@yahoo.com); Giti Emtiazi (Department of Biology, Faculty of Science, Isfahan University, Isfahan, Iran); Mehdi Hassanshahian (Department of [...]

Green synthesis methods by plant extracts leads to production of metal nanoparticles without using harsh, toxic, and expensive chemicals commonly used in physical/chemical processes. In this study, silver nanoparticles (AgNPs) were prepared easily, fast, cost-effectively and successfully using aqueous galls extract of Quercus infectoria (Q. infectoria) as a reducing and capping agent. The results revealed that AgNPs were highly stable and their morphologies were spherical with an average diameter of about 33 nm. The galls extract and AgNPs showed excellent antibacterial activities toward four types of bacteria. The antioxidant ability of galls extract and AgNPs was evaluated by DPPH assay and showed considerable antioxidant potential. Cytotoxic activity of AgNPs was tested by MTT assay. AgNPs exhibited significant anticancer activity against human breast cancer cells (MCF-7). AgNPs synthesized by Q. infectoria galls extract with high antibacterial, antioxidant and anticancer activity would be favorable systems for bacterial disease and cancer treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND About 25,000 oil tankers are transported annually through the Persian Gulf in Iran. Therefore, oil pollution in this region is very high. Research on the use of marine bacteria to degrade crude oil has yielded good results in recent years. The present study investigates bacteria that are symbiotic with marine corals and their ability to degrade crude oil. Corals were collected from five regions in the Persian Gulf and enriched with decomposing bacteria in ONR7a culture. After biochemical and molecular identification of bacterial isolates, the ability of the strains to degrade crude oil by spectrophotometric, gravimetric, and Gas Chromatography‐ Mass Spectroscopy (GC‐MS) methods was investigated. RESULTS: Finally, 26 bacterial strains were identified from 5 coral samples. The efficient strains that had the highest crude‐oil degradation belonged to genera Cobetia, Shewanella, Alcanivorax, and Cellulosimicrobium. Strains IAUK3568, IAUK3568, IAUK3502, IAUK3531, and IAUK3552 exhibited a maximum degradation of crude oil of 93.5%, 88.13%, 87.24%, 85.17%, and 77.3%, respectively. CONCLUSION: The results showed that all bacterial isolates degrade medium‐chain alkanes better than long‐ and short‐chain alkanes. The data obtained in this study confirm that the corals of the Persian Gulf have the necessary bacterial diversity to decompose crude oil and, consequently, reduce pollution in this region. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Microbial resistance is increasing worldwide. Investigations are underway to use nanoparticles as antimicrobial agents to reduce microbial resistance. Seven human pathogenic bacteria were selected according to common hospital infection bacteria: both gram-positive and negative. In this study, imipenem and ciprofloxacin antibiotics were used separately and in combination with human serum albumin and coacervation method for the preparation of nanoparticles. Dynamic light scattering (DLS), scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) were used to investigate the properties of nanoparticles. Antibacterial activity was determined and compared using the disk diffusion technique and minimum inhibitory concentration (MIC) was determined. The results of DLS for imipenem, ciprofloxacin and the combination of both antibiotics were 85 nm, 135 nm, and 120 nm, and for SEM were 79.9 nm, 122.2 nm, and 111 nm, respectively. All of the synthesized nanoparticles have a spherical shape. The antibacterial effect on the disk diffusion test for Acinetobacter baumannii bacteria was more noticeable in all three HSA nanoparticle compositions than other bacteria. The use of antibiotics in the form of HSA nanoparticles reduced the MIC. This value was more significant for nanoparticles carrying both ciprofloxacin and imipenem on methicillin-resistant Staphylococcus aureus and Streptococcus mutans bacteria. From the results of this study, it can be concluded that the use of HSA nanoparticles carrying the aforementioned antibiotics has more antibacterial effect against the bacteria of this study, especially S. mutans, than their free form. [ABSTRACT FROM AUTHOR]

Aromatic hydrocarbons are carcinogenic contaminants produced through natural and anthropogenic sources. The utilization of bacteria plays a crucial role in aromatic compounds bioremediation. For the isolation of mono- and di-aromatic hydrocarbon (phenol and naphthalene) degrading bacteria, samples were collected from five zones in Sarcheshmeh copper mine, Iran. The total aromatic hydrocarbon degrading bacteria were quantified by the most probable number (MPN) and the colony-forming unit (CFU) methods. The results were indicated that most of the bacteria communities degrade aromatic compounds aggregated in the Concenter Weighted (CW) metals' mine site. Totally 37 aromatic hydrocarbons (phenol and naphthalene) degrading bacteria were isolated that capably degraded 200 mg l−1 of aromatic compounds over 7 days. Four strains were able to degrade up to 600 mg l−1 of phenol and naphthalene during 7 days. The strains were molecularly identified that belong to the genera: Achromobacter ruhlandii AHB15N and Bacillus pumilus AHB19N (as naphthalene degraders) and Acinetobacter calcoaceticus AHB26P and Comamonas testosteroni AHB32P (as phenol degraders). This study was the first investigation for the screening and identification of phenol and naphthalene degrading bacterial strains from a mine environment in Iran. These isolated strains with strong aromatic hydrocarbon degrading potentials are recommended for the bioremediation of aromatic compounds in polluted environments. [ABSTRACT FROM AUTHOR]

The use of medicinal plants has been considered due to increasing bacterial resistance to antibiotics. Semenovia suffruticosa is a plant with high potential in medicine. The aim of this study was to evaluate the antibacterial activities and gas chromatography–mass spectrometry (GC-MS) analyses of the essential oil of S. suffruticosa from four regions in Kerman: Hezar Mountain, Laleh Zar, Bidkhan, and Rabor. The essential oil of this plant was extracted by Clevenger. The antibacterial activities were evaluated against three Gram-negative bacteria (P. aeruginosa, K. pneumonia, Acinetobacter) and three Gram-positive bactria (B. subtilis, S. aureus, S. pneumoniae). By disk diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined. The composition of essential oil was identified by GC-MS analysis. In our study, most yield of essential oil of S. suffruticosa was 1.2% from the Laleh Zar region and the main components were Z-β-ocimene (25.4%) in Laleh Zar, linalool (17.7%) in Hezar, Z-β-ocimene (18.5%) in Bidkhan, and β-pinene (10.5%) in the Rabor region. Maximum inhibition zone by the essential oil from region Bidkhan was observed against K. pneumoniae (30 mm). The MIC value for S. suffruticosa collected from Laleh Zar was 1.25 mg/ml against S. aureus and S. pneumonia. The results of this study confirm that the significant antibacterial effects of S. suffruticosa and make it a valuable compound in essential oils for pharmaceutical use and a good replacement for chemical antibiotics. Environmental conditions can result in a difference in yields and components; this can be considered significant potential for this plant. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the antimicrobial effects of Momordica charantia against pathogenic bacteria. Methods: Extract of M. charantia species was extracted using Rotary device. Minimum Inhibitory Concentration (MIC) and Minimum Bacterial Concentration (MBC) of extract 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 extract against bacteria was 12.5 ppm, (Vibrio cholera, Pseudomonas aeruginosa and E. coli) the results also showed that only one inhibited. However, the highest inhibitory concentration was estimated 25 ppm against Shigella dysenteriae and Bacillus cereus and highest bactericidal concentration was estimated 25 and 50 ppm. Conclusion: The results of this study show good antimicrobial effects of M. charantia on pathogenic bacteria and these medicinal plants can be used to treat infections caused by bacteria. [ABSTRACT FROM AUTHOR]

Acid mine drainage (AMD) is an environmental pollution that is generated from the oxidation of sulfide minerals that exist in the mine dumps. AMD causes pollution of surface and underground waters and lead to distribution of heavy metals into the environment. The aim of this research is isolation and identification of heterotrophic iron and sulfur-oxidizing bacteria from AMD of Sarcheshmeh copper mine. The mine samples were collected from six different locations of the mine. Iron and sulfur-oxidizing heterotrophic bacteria were quantified with serial dilution and most probable number methods. Heterotrophic oxidizing bacteria were screened by three methods: decrease in pH, sulfate ion production activity and growth rate. Most efficient heterotrophic oxidizing bacteria were identified by molecular method. The results of this research show that the maximum quantity of these bacteria in Sarcheshmeh copper mine relate to dumps number 32 and 17 with value 8 × 10 and 5.9 × 10, respectively. Thirty two strains were isolated from six different locations of this copper mine and after screening tests 15 effective strains were selected and 8 strains were identified by molecular method. The results of the molecular identification showed that eight strains belong to: Bacillus thuringiensis strain DP26-1, Bacillus sp. strain DP-15-4, Pseudochrobactrum sp., Brevundimonas sp., Brevibacillus formosus, Sphingomonas ginsenosidimutans, Pseudomonas brassicacearum, Sphingomonas paucimobilis. Most efficient heterotrophic oxidizing bacteria related to DP-17-3 and DP-30-1 strains that produce high percentage of sulfate ion (270 and 223 ppm) also decrease dramatically the pH (4.2 and 4.9). Application of these bacteria in bioleaching process can enhanced efficiency of metal extraction in this copper mine. [ABSTRACT FROM AUTHOR]

Phenol is one of the major aromatic and carcinogenic pollutants. Phenol degrader bacteria from the coal tar mine of Zarand have been identified with the bacterial growth assayed in different concentrations. Four samples were collected from different sites of the mine. Total heterotrophic and phenol-degrading bacteria were quantified and the results indicated that most of phenol degrader bacteria aggregated in the sludge aggregate site. Eleven phenol degrading bacteria were isolated that were capable of degrading 200 ppm phenol in 7 d, 6 bacterial strains were selected for capability of growth on more concentration of phenol and biochemical characteristics. Finally, two strains named isolates 42P and 53P were selected for analysis of 16S rRNA sequences. Strain 42P belongs to Chryseobacterium indologenes AHB42P while Strain P53 belongs to Pseudomonas putida AHB53P which is capable of degrading 1,800 ppm phenol. The results support the idea that environments in mines can serve as a source of bacterial strains for purposes of bioremediation. [ABSTRACT FROM AUTHOR]

Phenols are distributed either as natural or artificial mono-aromatic compounds in various environmental sites as major pollutants. The objective of this study was the immobilization of the phenol degrading bacteria P. putida P53 and A. scleromae P69 in sodium-alginate beads and sawdust as carriers and evaluate the biodegradation ability. The biodegradation ability of strains in free form were evaluated and P. putida P53 was shown to biodegrade up to 1,800 mg/L phenol. Bacterial biomass was prepared and attached to carrier with entrapment and attachment methods. Prepared beads were added to Erlenmeyer flasks containing different concentrations of phenol in BH medium (1,800, 2,200, 2,600 and 3,000 mg/L). According to the results, phenol biodegradation efficiency of immobilized bacteria in sawdust was more than free form. Strain P53 had better biodegradation than P69 strain. Attachment and entrapments into carriers had positive results, Scanning electron micrograph (SEM) images indicated that alginate beads were globular shapes (10 nm), and strains aggregated between the large cavities of the matrix. Comparison of sawdust and alginate as carriers for degradation of phenol at high concentrations demonstrated that sawdust improved biodegradation better, and immobilized P53 into sawdust entrapped in sodium-alginate beads can be used for biodegradation purposes. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the antimicrobial and anti-biofilm effects of Mentha piperita and Zataria multiflora on some pathogenic bacteria. Methods: Mentha piperita and Zataria multiflora essential oils were obtained by using the clevenger device. The bacterial cultures were prepared as standard samples. Finally, antimicrobial and anti-biofilm activity was determined by microdilution method. Results: The results of this study showed that the lowest inhibitory concentration of essential oil of Zataria multiflora was 1.25 mg / ml, while the rest of the bacteria were inhibited at a concentration of 2.5 mg / ml. The lowest and highest inhibitory concentrations were found as 1.25 and 5 mg / ml against Pseudomonas aeruginosa. Conclusion: The results of the study showed that Z. multiflora essential oil showed antimicrobial and anti-biofilm activity that could be used to treat infections caused by these bacteria. [ABSTRACT FROM AUTHOR]

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. Conclusions: 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. [ABSTRACT FROM AUTHOR]

PAHs are aromatic hydrocarbons with two or more fused benzene rings. They are formed during the thermal breakdown of organic molecules and their succeeding recombination. Naphthalene is the simplest (PAHs) that is carcinogenic. Bioremediation method is considered as an economical and safe approach for the elimination of aromatic compounds from environment. The bacteria were capable to grow on various hydrocarbons like naphthalene. The aim of this research is to isolate and identify naphthalene-degrading bacteria from the coal mine of Zarand. Four samples of water and sludge from various sites of the mine were collected. These sites include the following: Main coal vacate site (MC), Inoculum Sump site (IB), Sludge aggregate site (SA), and Near sludge aggregate site (NF). In this study, 12 bacterial strains that utilize naphthalene at initial concentration 200 mg/L (ppm) as carbon and energy sources for growth were isolated from the Zarand mine in Iran. In addition, bacterial cell density was assayed by measuring the OD600. In addition, total naphthalene-degrading bacteria were quantified with the most probable number (MPN) procedure using microtiter plates and the colony-forming unit (CFU) method. The results had shown that most of the naphthalene degrader bacteria aggregated in (SA) site. Six bacteria, isolated from wastewater and oil-contaminated soil showed great potential as naphthalene degraders up to 400 (ppm) and selected for biochemical characteristics. Naphthalene tolerance of the strains in various concentrations of naphthalene indicates that the strain 38 N can grow best at 600 (ppm) naphthalene. This strain was identified based on 16S rRNA gene analysis that showed belonging to Sphingobacterium multivorum AHB38N. [ABSTRACT FROM AUTHOR]

Microbial oxidation of iron and sulfur are important steps in biogeochemical cycles in mining environments. The aim of this study was the enrichment and identification of two important groups of bacteria that are involved in bioleaching of copper ores. Some soil samples were collected from the Maiduk copper mine. Iron-oxidizing bacteria were enriched in 9K medium containing ferrous sulfate, and sulfur oxidizers were enriched in 9K medium containing powdered sulfur instead of ferrous sulfate as energy source. After three subcultures, autotrophic bacteria were isolated on 9K agarose medium with appropriate energy sources. The autotrophic bacteria from the enrichments were identified by amplification of 16S rRNA gene and sequencing. Bioleaching experiments were performed in 100 ml of 9K medium containing 5 g of low-grade copper ore instead of ferrous sulfate. Twelve different iron and sulfur-oxidizing bacteria were isolated from the collected soil samples of Maiduk copper mine. Molecular identification indicated that two prevalent strains in the ore enrichments could be assigned to theAcidithiobacillus ferooxidansstrain HGM and theThiobacillus thioparusstrain HGE. These two strains reached their logarithmic phase of growth after 8 days of incubation in their respective media at 30°C. Of these two cultures, strain HGM leached more copper ore (300 ppm) from the Maiduk copper ore than did strain HGE (200 ppm). Application of these two strains to the Maiduk copper ore in situ and to ore heaps should improve the leaching process. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Considering the importance of new antibiotics, the potential antibacterial activity of ethyl acetate and Methanol extracts of Securigera securidaca, Withania sominefra, Rosmarinus officinalis and Aloe vera plants against important human pathogens was studied. Methods: Streptococcus pneumoniae, Enterococcus faecalis, Proteus mirabilis, Staphylococcus aureus, E. coli, P. aeruginosa were the pathogenic bacteria used to determine the antibacterial effect of ethyl acetate and mathanol extracts of Securigera securidaca, Withania sominefra, Rosmarinus officinalis and Aloe vera in broth micro-dilution method. Results: The results of studying the methanol extract of S. securidaca with the lowest inhibitory concentration of 25, showed that all used bacterial pathogens were inhibited at this concentration, while the lowest inhibitory concentration of ethyl acetate extract of Securigera securidaca was 12.5, which were P. mirabilis and S. aureus is inhibited in this concentration. The highest bactericidal concentration (MBC) of S. securidaca ethyl acetate extract was 100, and S. aureus, P. aeruginosa were inhibitory at this concentration. The lowest inhibitory concentration of methanol extract of W. sominefra was 6.25, which S. pneumoniae, P. mirabilis, S. aureus and E. coli bacteria were inhibited at this concentration, while the highest inhibitory concentration was observed against P. aeruginosa (25 ppm), The lowest inhibitory concentration of the ethyl acetate W. sominefra extract was 3.1ppm in comparison with P. mirabilis and E. coli. Conclusion: In conclusion, it seems that S. securidaca, W. sominefra, R. officinalis and Aloe vera extracts could inhibit the growth of all of the mentioned bacteria. [ABSTRACT FROM AUTHOR]

The acidophilic and thermophilic cellulase would facilitate the conversion of lignocellulosic biomass to biofuel. In this study, Bacillus sonorensis HSC7 isolated as the best thermophilic cellulose degrading bacterium from Gorooh hot spring. 16S rRNA gene sequencing showed that, this strain closely related to the B. sonorensis . CMCase production was considered under varying environmental parameters. Results showed that, sucrose and (NH 4 ) 2 SO 4 were obtained as the best carbon and nitrogen sources for CMCase production. B. sonorensis HSC7 produced CMCase during the growth in optimized medium supplemented with agricultural wastes as sole carbon sources. The enzyme was active with optimum temperature of 70 °C and the optimum CMCase activity and stability observed at pH 4.0 and 5.0, respectively. These are characteristics indicating that, this enzyme could be an acidophilic and thermophilic CMCase. Furthermore, the CMCase activity improved by methanol (166%), chloroform (152%), while it was inhibited by DMF (61%). The CMCase activity was enhanced in the presence of Mg +2 (110%), Cu +2 (116%), Triton X-100 (118%) and it retained 57% of its activity at 30% NaCl. The compatibility of HSC7 CMCase varied for each laundry detergent, with higher stability being observed in the presence of Taj® and darya®. This enzyme, that is able to work under extreme conditions, has potential applications in various industries. [ABSTRACT FROM AUTHOR]

Naphthalene is a ubiquitous pollutant of the marine environment, and naphthalene biodegradation has been receiving constant scientific consideration. For cleanup of aromatic contaminated sites, bioremediation methods are considered as economical and safe approaches for the marine environment. The aims of this research are isolation and characterization of naphthalene-degrading bacteria from some marine samples of the Persian Gulf. Fifty four naphthalene-degrading bacteria were isolated from marine samples (sediment and seawater) that are enriched in ONR7a medium with naphthalene as the only carbon source. Some screening tests such as growth at high concentration of naphthalene, bioemulsifier production and surface hydrophobicity were done to select the best and prevalent strains for naphthalene degradation. Determination of the nucleotide sequence of the gene encoding for 16S rRNA shows that these isolated strains belong to these genera: Shewanella , Salegentibacter , Halomonas , Marinobacter , Oceanicola , Idiomarina and Thalassospira . These strains can degrade half of the percentage of naphthalene in 10 days of incubation. This research is the first report on isolation of these genera from the Persian Gulf as naphthalene-degrader. [ABSTRACT FROM AUTHOR]

In order to better understand the effects of biostimulation and bioaugmentation processes on a marine microbial community, three different mesocosm experiments were planned. Natural seawater (10.000 L) was artificially polluted with crude oil (1 L) and (1) inorganic nutrients (Biostimulating Mesocosm, BM), (2) inorganic nutrients and an inoculum of Alcanivorax borkumensis SK2 (Single Bioaugmentation Mesocosm, SBM), (3) inorganic nutrients and inoculums of A . borkumensis SK2 and Thalassolituus oleivorans MIL-1 (Consortium Bioaugmentation Mesocosm, CBM). During the experimental period (20 days), samples were taken from each mesocosm and the community structure was analyzed by PCR–DGGE. The 16S rRNA gene DGGE banding patterns and sequence analysis demonstrated that biostimulation had the lowest effect on microbial biodiversity in the mesocosms; however, the biodiversity of the marine microbial community dramatically decreased in the CBM (Shannon index was 0.6 in T3). The community structures among the three mesocosms were also markedly different, and major bacteria derived from DGGE bands were related to uncultured Gamma Proteobacteria. The biodegradation results show that the Single Bioaugmentation Mesocosm (SBM) system had the highest percentage of degradation (95%) in comparison to the BM mesocosm (80%) and CBM (70%). [ABSTRACT FROM AUTHOR]

Background: A large number of plants are used for treatment of diseases because of their antimicrobial activities. This study aims to investigate the antimicrobial effects of some plants on the f ood pathogenic bacteria. Methods: Plant extracts were obtained using the rotary system, the minimum inhibitory concentration ( MIC) by diluting method against bacteria was determined. Results: Results showed that the lowest MIC of the Peganum harmala was 3.1 ppm and the highest inhibitory concentration was 6.25 ppm for inhibiting the Vibrio cholerae. Conclusion: The present study confirms the use of this extract as an antibacterial agent. Further research is required to evaluate the practical value of its therapeutic application. [ABSTRACT FROM AUTHOR]

Symbiotic associations are complex partnerships that can lead to new metabolic capabilities and the establishment of novel organisms. The diversity of these associations is very broad and there are still many mysteries about the origin and the exact relationship between the organisms that are involved in a symbiosis. The aim of the present study is to find symbiotic crude-oil degrading bacteria in the mussels that collected from the Persian Gulf. Fifteen crude-oil degrading bacteria were isolated from Mactra stultorum mussel that collected from oil contaminated area at Persian Gulf. According to high growth rate on crude oil five strains were selected from 15 isolated strains for more study. Determination of the nucleotide sequence of the gene encoding 16S rRNA show that these isolated strains belong to: Alcanivorax dieselolei strain BHA25, Idiomarina baltica strain BHA28, A. dieselolei strain BHA30, Alcanivorax sp. strain BHA32 and Vibrio azureus strain BHA36. Analysis of remaining of crude oil by Gas Chromatography (GC) confirmed that these strains can degrade: 64%, 63%, 71%, 58% and 75% of crude oil respectively. [ABSTRACT FROM AUTHOR]

Introduction: Microbial biofilms have attracted interest in recent years because they have become the most important cause of nosocomial infections. This study was aimed to examine the antibacterial activities of Peganum harmala extracts on the development of microbial biofilms and planktonic form of six pathogenic bacteria which include Staphylococcus aureus, Bacillus cereus, Streptococcus pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae. Materials and methods: Antimicrobial activities of the crude extracts against the planktonic form of bacteria were evaluated by using disc diffusion method, minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values were determined by a macrobroth dilution technique. Anti- biofilm effects of the extracts were assessed by microtiter plate method. Results: According to the results, P. harmala extracts could inhibit test bacteria in planktonic form. To inhibit biofilm formation, biofilm metabolic activity and eradication of established biofilms, efficiency of the extracts depended on concentration. The highest inhibitory effects of P. harmala extracts were observed on biofilm formation of S. aureus (90.28%) also, the greatest demolish were observed on S. pneumonia biofilm (77.76%). These extracts cause dramatically decrease the metabolic activity of bacteria in biofilm structures, in this case the decrement of B. cereus were highest (69.98%) compared to other tested bacteria. Discussion and conclusion: Therefore, it can be suggested that P.harmala extracts applied as antimicrobial agents against testing bacteria particularly in biofilm forms. [ABSTRACT FROM AUTHOR]

To date, little is known about existing relationships between mussels and bacteria in hydrocarbon-contaminated marine environments. The aim of this study is to find crude oil degrading bacteria in some mussels at the Persian Gulf. Twenty eight crude oil degrading bacteria were isolated from three mussels species collected from oil contaminated area at Persian Gulf. According to high growth and degradation of crude oil four strains were selected between 28 isolated strains for more study. Determination the nucleotide sequence of the gene encoding for 16S rRNA show that these isolated strains belong to: Shewanella algae isolate BHA1, Micrococcus luteus isolate BHA7, Pseudoalteromonas sp. isolate BHA8 and Shewanella haliotis isolate BHA35. The residual crude oil in culture medium was analysis by Gas Chromatography (GC). The results confirmed that these strains can degrade: 47.24%, 66.08%, 27.13% and 69.17% of crude oil respectively. These strains had high emulsification activity and biosurfactant production. Also, the effects of some factors on crude oil degradation by isolated strains were studied. The results show that the optimum concentration of crude oil was 2.5% and the best degradation take place at 12% of salinity. This research is the first reports on characterization of crude oil degrading bacteria from mussels at Persian Gulf and by using of these bacteria in the field the effect of oil pollution can be reduce on this marine environment. [ABSTRACT FROM AUTHOR]

Phenol is one of the major aromatic pollutants among variety of toxic compounds. Phenol is a man-made as well as a naturally occurring aromatic compound and an important intermediate in the biodegradation of natural and industrial aromatic compounds. To clean up the aromatic contaminated sites a bioremediation method is considered as an economical and safe approach for the environment. In this study, 10 phenol-degrading bacterial strains were isolated from three sites at Midok copper mine in Shahrbabak. These sites include: Magnetit site (WG), Hematit site (WH) and Near Hematit site (NH). Total heterotrophic and phenol degrading bacteria were quantified with most probable number (MPN) and colony forming unit (CFU) methods. The results of this study show that the (WG) site of the mine have the highest phenol degrading bacteria. Totally 10 phenol degrading bacteria were isolated from three sites in Midok copper mine. Then, five bacterial strains were selected according to high growth rate and phenol degradation. Finally two strains named isolates P62 and 69P were selected for analysis of 16S rRNA sequences. Strain P62 belongs to Pseudomonas putidaAHBP62 and strain P69 is related to Arthrobacter scleromaeAHB69P that has capability degradation of 600 (ppm) phenols in 7 days. By using these degradative bacteria in contaminated mine sites the environmental pollution can be managed. [ABSTRACT FROM AUTHOR]

Objective: Microorganisms are responsible for many problems in industry and medicine because of biofilm formation. Therefore, this study was aimed to examine the effect of Thymus vulgaris (T. vulgaris) extracts on the planktonic form and biofilm structures of six pathogenic bacteria. Materials and methods: Antimicrobial activities of the plant extracts against the planktonic form of the bacteria were determined using the disc diffusion method. MIC and MBC values were evaluated using macrobroth dilution technique. Anti-biofilm effects were assessed by microtiter plate method. Results: According to disc diffusion test (MIC and MBC), the ability of Thymus vulgaris (T. vulgaris ) extracts for inhibition of bacteria in planktonic form was confirmed. In dealing with biofilm structures, the inhibitory effect of the extracts was directly correlated to their concentration. Except for the inhibition of biofilm formation, efficacy of each extract was independent from type of solvent. Conclusion: According to the potential of Thymus vulgaris (T. vulgaris) extracts to inhibit the test bacteria in planktonic and biofilm form, it can be suggested that Thymus vulgaris (T. vulgaris) extracts can be applied as antimicrobial agents against the pathogenic bacteria particularly in biofilm forms. [ABSTRACT FROM AUTHOR]