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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]

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]

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]

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]

Highlights: [•] Hexadecane degrading bacteria were isolated from petroleum reservoirs waste water. [•] Eight strains with high growth on hexadecane were identified. [•] Direct relationship was found between emulsification activity and alkane degradation. [ABSTRACT FROM AUTHOR]

Background: By considering the importance and role of soil in the health of humanity, it is important to remove the presence of harmful compounds, such as phenol., Methods: In this study, four types of soil and leaf samples were collected from Kerman, Iran, and the amounts of heterotrophic and degradation bacteria were determined using the serial dilution and most probable number (MPN) methods. The amount of removed phenol was investigated using the Gibbs method with different concentrations of phenol. Then, an isolate with the highest percentage of phenol degradation was identified as the superior strain using 16 sRNA sequencing. The effects of the different factors, such as the carbon source (1% molasses and 1 g glucose), nitrogen source (0.1 g yeast extract), mixed culture, and time (14 and 28 days), on the biodegradation ability of the superior strain was investigated., Results: A total of 18 bacterial strains were isolated from the samples. Isolate B3 had the highest rate (75%) of phenol degradation, at a concentration of 1000 ppm, meaning it was identified as the superior strain. The molecular analysis results identified this isolate as the Comamonas testosteroni strain F4. This bacterium can degrade 89% of the phenol at 30 °C, 180 rpm, and 800 ppm over 28 days. C. testosteroni did not show a favorable phenol degradation ability in the presence of the investigated carbon sources, while this ability was also reduced in mixed cultures., Conclusions: C. testosteroni bacterial strain isolated from soil samples of pistachio orchards in Kerman, Iran, has a favorable ability to biodegrade phenol., Competing Interests: The authors declare no conflict of interest., (© 2023 The Author(s). Published by IMR Press.)