scholarly journals Aromatic Hydrocarbon Removal by Novel Extremotolerant Exophiala and Rhodotorula Spp. from an Oil Polluted Site in Mexico

2020 ◽  
Vol 6 (3) ◽  
pp. 135 ◽  
Author(s):  
Martín R. Ide-Pérez ◽  
Maikel Gilberto Fernández-López ◽  
Ayixon Sánchez-Reyes ◽  
Alfonso Leija ◽  
Ramón Alberto Batista-García ◽  
...  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Aromatic Compounds ◽  
High Salinity ◽  
Polyaromatic Hydrocarbons ◽  
Carbon Sources ◽  
Optimal Growth ◽  
Polluted Site ◽  
Removal Capacity ◽  
Wide Range ◽  
Hydrocarbon Removal

Since Aromatic hydrocarbons are recalcitrant and toxic, strategies to remove them are needed. The aim of this work was to isolate fungi capable of using aromatic hydrocarbons as carbon sources. Two isolates from an oil polluted site in Mexico were identified through morphological and molecular markers as a novel Rhodotorula sp. and an Exophiala sp. Both strains were able to grow in a wide range of pH media, from 4 to 12, showing their optimal growth at alkaline pH’s and are both halotolerant. The Exophiala strain switched from hyphae to yeast morphotype in high salinity conditions. To the best of our knowledge, this is the first report of salt triggering dimorphism. The Rhodotorula strain, which is likely a new undescribed species, was capable of removing singled ringed aromatic compounds such as benzene, xylene, and toluene, but could not remove benzo[a] pyrene nor phenanthrene. Nevertheless, these hydrocarbons did not impair its growth. The Exophiala strain showed a different removal capacity. It could remove the polyaromatic hydrocarbons but performed poorly at removing toluene and xylene. Nevertheless, it still could grow well in the presence of the aromatic compounds. These strains could have a potential for aromatic compounds removal.

scholarly journals Fervidobacterium changbaicum sp. nov., a novel thermophilic anaerobic bacterium isolated from a hot spring of the Changbai Mountains, China

2007 ◽  
Vol 57 (10) ◽  
pp. 2333-2336 ◽  
Author(s):  
Jingang Cai ◽  
Yanping Wang ◽  
Dongbo Liu ◽  
Yan Zeng ◽  
Yanfen Xue ◽  
...  
Keyword(s):  
Hot Spring ◽  
Cell Envelope ◽  
Carbon Sources ◽  
Optimal Growth ◽  
Changbai Mountains ◽  
Rrna Gene ◽  
High Concentration ◽  
Gene Sequence Analysis ◽  
Wide Range ◽  
Bacterium Strain

A thermophilic, obligately anaerobic, rod-shaped bacterium (strain CBS-1T) was isolated from a hot spring mixture of water and mud of the Changbai Mountains, China. Strain CBS-1T was found to be non-sporulating, Gram-negative, with optimal growth at 75–80 °C. It grew on a wide range of carbon sources, including glucose, lactose, maltose, starch, sorbitol and pyruvate amongst others. The DNA G+C content of strain CBS-1T was 31.9 mol%. The 16S rRNA gene sequence analysis indicated that the strain was a member of the genus Fervidobacterium. The high concentration of C16 : 0 (52.2 %) in the fatty acid profile of the cell envelope supported its inclusion as a member of the genus Fervidobacterium. On the basis of the low values of DNA–DNA hybridization (25.8 and 20.5 %) and phenotypic features, strain CBS-1T represents a novel species of the genus Fervidobacterium, for which the name Fervidobacterium changbaicum sp. nov. is proposed. The type strain is CBS-1T (=DSM 17883T=JCM 13353T).

scholarly journals Nitrobenzoates and Aminobenzoates Are Chemoattractants for Pseudomonas Strains

2004 ◽  
Vol 70 (1) ◽  
pp. 285-292 ◽  
Author(s):  
Rebecca E. Parales
Keyword(s):  
Pseudomonas Putida ◽  
Aromatic Compounds ◽  
Carbon Sources ◽  
Chemotactic Response ◽  
Aromatic Acids ◽  
Wide Range ◽  
Catechol 1,2 Dioxygenase ◽  
Sense And Respond ◽  
Chemotaxis System ◽  
Broad Specificity

ABSTRACT Three Pseudomonas strains were tested for the ability to sense and respond to nitrobenzoate and aminobenzoate isomers in chemotaxis assays. Pseudomonas putida PRS2000, a strain that grows on benzoate and 4-hydroxybenzoate by using the β-ketoadipate pathway, has a well-characterized β-ketoadipate-inducible chemotactic response to aromatic acids. PRS2000 was chemotactic to 3- and 4-nitrobenzoate and all three isomers of aminobenzoate when grown under conditions that induce the benzoate chemotactic response. P. putida TW3 and Pseudomonas sp. strain 4NT grow on 4-nitrotoluene and 4-nitrobenzoate by using the ortho (β-ketoadipate) and meta pathways, respectively, to complete the degradation of protocatechuate derived from 4-nitrotoluene and 4-nitrobenzoate. However, based on results of catechol 1,2-dioxygenase and catechol 2,3-dioxygenase assays, both strains were found to use the β-ketoadipate pathway for the degradation of benzoate. Both strains were chemotactic to benzoate, 3- and 4-nitrobenzoate, and all three aminobenzoate isomers after growth with benzoate but not succinate. Strain TW3 was chemotactic to the same set of aromatic compounds after growth with 4-nitrotoluene or 4-nitrobenzoate. In contrast, strain 4NT did not respond to any aromatic acids when grown with 4-nitrotoluene or 4-nitrobenzoate, apparently because these substrates are not metabolized to the inducer (β-ketoadipate) of the chemotaxis system. The results suggest that strains TW3 and 4NT have a β-ketoadipate-inducible chemotaxis system that responds to a wide range of aromatic acids and is quite similar to that present in PRS2000. The broad specificity of this chemotaxis system works as an advantage in strains TW3 and 4NT because it functions to detect diverse carbon sources, including 4-nitrobenzoate.

scholarly journals Biodegradation of Aromatics Such as Benzene, Toluene and Phenol by Pseudomonas Strain

2020 ◽  
Vol 1 (3) ◽  
Author(s):  
Mahesh Arvind ◽  
Sneha Bhatt ◽  
Nichith K. R.
Keyword(s):  
Organic Compounds ◽  
Aromatic Hydrocarbons ◽  
Industrial Effluents ◽  
Optimal Growth ◽  
Life Forms ◽  
Biochemical Tests ◽  
Wide Range ◽  
Benzene Toluene ◽  
Promising Solution ◽  
High Concentrations

The environment is home to thousands of life forms and the day to day human activities are posing a serious threat to these organisms and leading them to the path of extinction. A wide range of pollutants are seen contaminating resources such as air, water and land. One major issue of water pollution is due to industrial effluents which includes a combination of phenolics and aromatic hydrocarbons. These organic compounds are said to be toxic to life even in minor quantities. An effective approach to detoxify these contaminated water sources and make it sustainable is by bioremediation. Microbes bioremediate the environment as they biodegrade the pollutants to obtain energy. Among aromatics, phenols and their derivatives from the principal group of environmental contaminants. Even at low levels they are toxic and they pose a threat to the biosphere because of their recalcitrant nature. Pseudomonas was the bacteria chosen for the study due to its versatile nature. The bacteria were isolated and characterized using biochemical tests. It was then subjected to degrade organic compounds such as benzene, toluene and phenol. The bacteria showed optimal growth in the presence of these compounds and could metabolize them effectively. A concentration of up to 6% benzene, 2% toluene and 0.5% phenol was found to be degraded. The aromatics were found to be assimilated by the end of 24 hours. The bacteria were successful in biodegradation of these aromatic hydrocarbons and proves to be a novel strain capable of biodegradation of these aromatics at such high concentrations and thus, proves to be a promising solution to decontaminate water resources that are affected due to them. 

scholarly journals Synthetic Approaches, Modification Strategies and the Application of Quantum Dots in the Sensing of Priority Pollutants

2021 ◽  
Vol 11 (24) ◽  
pp. 11580
Author(s):  
Rodney Maluleke ◽  
Oluwatobi Samuel Oluwafemi
Keyword(s):  
Quantum Dots ◽  
Polycyclic Aromatic Hydrocarbons ◽  
Organic Pollutants ◽  
Aromatic Hydrocarbons ◽  
Aromatic Compounds ◽  
Water Soluble ◽  
Sensing Applications ◽  
Wide Range ◽  
Polycyclic Aromatic ◽  
Nitro Aromatic

Polycyclic aromatic hydrocarbons (PAHs) and nitro-aromatic compounds (NACs) are two classifications of environmental pollutants that have become a source of health concerns. As a result, there have been several efforts towards the development of analytical methods that are efficient and affordable that can sense these pollutants. In recent decades, a wide range of techniques has been developed for the detection of pollutants present in the environment. Among these different techniques, the use of semiconductor nanomaterials, also known as quantum dots, has continued to gain more attention in sensing because of the optical properties that make them useful in the identification and differentiation of pollutants in water bodies. Reported studies have shown great improvement in the sensing of these pollutants. This review article starts with an introduction on two types of organic pollutants, namely polycyclic aromatic hydrocarbons and nitro-aromatic explosives. This is then followed by different quantum dots used in sensing applications. Then, a detailed discussion on different groups of quantum dots, such as carbon-based quantum dots, binary and ternary quantum dots and quantum dot composites, and their application in the sensing of organic pollutants is presented. Different studies on the comparison of water-soluble quantum dots and organic-soluble quantum dots of a fluorescence sensing mechanism are reviewed. Then, different approaches on the improvement of their sensitivity and selectivity in addition to challenges associated with some of these approaches are also discussed. The review is concluded by looking at different mechanisms in the sensing of polycyclic aromatic hydrocarbons and nitro-aromatic compounds.

scholarly journals The Protein Kinase Snf1 Is Required for Tolerance to the Ribonucleotide Reductase Inhibitor Hydroxyurea

2004 ◽  
Vol 24 (6) ◽  
pp. 2560-2572 ◽  
Author(s):  
Caroline Dubacq ◽  
Anne Chevalier ◽  
Carl Mann
Keyword(s):  
Ribonucleotide Reductase ◽  
Stress Responses ◽  
Cellular Response ◽  
Kinase Activity ◽  
Carbon Sources ◽  
Optimal Growth ◽  
Genotoxic Stress ◽  
Snf1 Kinase ◽  
Wide Range ◽  
High Level

ABSTRACT The Snf1/AMP-activated kinases are involved in a wide range of stress responses in eukaryotic cells. We discovered a novel role for the Snf1 kinase in the cellular response to genotoxic stress in yeast. snf1 mutants are hypersensitive to hydroxyurea (HU), methyl-methane sulfonate, and cadmium, but they are not sensitive to several other genotoxic agents. HU inhibits ribonucleotide reductase (RNR), and deletion of SNF1 also increased the growth defects of an rnr4 ribonucleotide reductase mutant. The snf1 mutant has a functional checkpoint response to HU insofar as cells arrest division normally and derepress the transcription of RNR genes. The sensitivity of snf1 to HU or to RNR4 deletion may be due to posttranscriptional defects in RNR function or to defects in the repair of, and recovery from, stalled replication forks. The Mig3 repressor was identified as one target of Snf1 in this pathway. Genetic and biochemical analyses suggest that a weak kinase activity is sufficient to confer resistance to HU, whereas a high level of kinase activity is required for optimal growth on carbon sources other than glucose. Quantitative regulation of Snf1 kinase activity may contribute to the specificity of the effector responses that it controls.

Regioselective Functionalization of N-Fused Heteroaromatics via FeCl3-Catalyzed Nucleophilic Addition to Activated N-Heterocycles

Synthesis ◽  
2020 ◽  
Author(s):  
Ikyon Kim ◽  
Sung June Kim ◽  
Sunhee Lee
Keyword(s):  
Aromatic Compounds ◽  
Nucleophilic Addition ◽  
Chemical Space ◽  
Wide Range ◽  
Regioselective Functionalization

AbstractBroadening of nitrogen-fused heteroaromatic chemical space such as indolizine and pyrrolo[1,2-a]pyrazine was achieved via FeCl­3-catalyzed nucleophilic addition of these N-fused aromatic compounds to a wide range of azolinium systems generated in situ, leading to novel N-fused heteroaromatic scaffolds with dearomatized N-heterocyclic substituents regioselectively. Nucleophilic addition of indolizines and pyrrolo[1,2-a]pyrazines mainly occurred at the C1 position of the isoquinoliniums and at the C4 site of the quinoliniums.

scholarly journals Burkholderia thailandensis E264 as a promising safe rhamnolipids’ producer towards a sustainable valorization of grape marcs and olive mill pomace

2021 ◽  
Author(s):  
Alif Chebbi ◽  
Massimiliano Tazzari ◽  
Cristiana Rizzi ◽  
Franco Hernan Gomez Tovar ◽  
Sara Villa ◽  
...  
Keyword(s):  
Energy Source ◽  
Olive Oil ◽  
Low Cost ◽  
Carbon Sources ◽  
Burkholderia Thailandensis ◽  
Rhamnolipid Production ◽  
Key Points ◽  
Wide Range ◽  
Long Chain ◽  
Olive Mill

Abstract Within the circular economy framework, our study aims to assess the rhamnolipid production from winery and olive oil residues as low-cost carbon sources by nonpathogenic strains. After evaluating various agricultural residues from those two sectors, Burkholderia thailandensis E264 was found to use the raw soluble fraction of nonfermented (white) grape marcs (NF), as the sole carbon and energy source, and simultaneously, reducing the surface tension to around 35 mN/m. Interestingly, this strain showed a rhamnolipid production up to 1070 mg/L (13.37 mg/g of NF), with a higher purity, on those grape marcs, predominately Rha-Rha C14-C14, in MSM medium. On olive oil residues, the rhamnolipid yield of using olive mill pomace (OMP) at 2% (w/v) was around 300 mg/L (15 mg/g of OMP) with a similar CMC of 500 mg/L. To the best of our knowledge, our study indicated for the first time that a nonpathogenic bacterium is able to produce long-chain rhamnolipids in MSM medium supplemented with winery residues, as sole carbon and energy source. Key points • Winery and olive oil residues are used for producing long-chain rhamnolipids (RLs). • Both higher RL yields and purity were obtained on nonfermented grape marcs as substrates. • Long-chain RLs revealed stabilities over a wide range of pH, temperatures, and salinities

scholarly journals Sporulation in solventogenic and acetogenic clostridia

2021 ◽  
Author(s):  
Mamou Diallo ◽  
Servé W. M. Kengen ◽  
Ana M. López-Contreras
Keyword(s):  
Current Knowledge ◽  
Carbon Sources ◽  
Cost Effective ◽  
Biotechnological Production ◽  
Key Points ◽  
Wide Range ◽  
Potential Applications ◽  
A Cell ◽  
Sporulation Initiation ◽  
Solventogenic Clostridia

AbstractThe Clostridium genus harbors compelling organisms for biotechnological production processes; while acetogenic clostridia can fix C1-compounds to produce acetate and ethanol, solventogenic clostridia can utilize a wide range of carbon sources to produce commercially valuable carboxylic acids, alcohols, and ketones by fermentation. Despite their potential, the conversion by these bacteria of carbohydrates or C1 compounds to alcohols is not cost-effective enough to result in economically viable processes. Engineering solventogenic clostridia by impairing sporulation is one of the investigated approaches to improve solvent productivity. Sporulation is a cell differentiation process triggered in bacteria in response to exposure to environmental stressors. The generated spores are metabolically inactive but resistant to harsh conditions (UV, chemicals, heat, oxygen). In Firmicutes, sporulation has been mainly studied in bacilli and pathogenic clostridia, and our knowledge of sporulation in solvent-producing or acetogenic clostridia is limited. Still, sporulation is an integral part of the cellular physiology of clostridia; thus, understanding the regulation of sporulation and its connection to solvent production may give clues to improve the performance of solventogenic clostridia. This review aims to provide an overview of the triggers, characteristics, and regulatory mechanism of sporulation in solventogenic clostridia. Those are further compared to the current knowledge on sporulation in the industrially relevant acetogenic clostridia. Finally, the potential applications of spores for process improvement are discussed.Key Points• The regulatory network governing sporulation initiation varies in solventogenic clostridia.• Media composition and cell density are the main triggers of sporulation.• Spores can be used to improve the fermentation process.

scholarly journals Consumer Neuroscience as a Tool to Monitor the Impact of Aromas on Consumer Emotions When Buying Food

2021 ◽  
Vol 11 (15) ◽  
pp. 6692
Author(s):  
Jakub Berčík ◽  
Katarína Neomániová ◽  
Jana Gálová ◽  
Anna Mravcová
Keyword(s):  
Aromatic Compounds ◽  
Competitive Environment ◽  
Retail Operations ◽  
Consumer Neuroscience ◽  
Wide Range ◽  
Consumer Emotions ◽  
Affective Processes ◽  
Effective Selection ◽  
The Subject ◽  
The Impact

Building a unique USP sales argument (unique selling proposition) through various forms of in-store communication comes to the fore in a challenging competitive environment. Scent as a means to influence the purchase of goods or services has a long history, however, aromachology as field of in-store communication is a matter of the present. This new trend, the importance and use of which has grown in recent years, is the subject of a wide range of research. In order to increase the efficiency of these elements, it is necessary to familiarise ourselves with the factors that affect the customer, whether that be consciously or unconsciously. Consumer neuroscience is addressed in this area. This paper deals with the comprehensive interdisciplinary investigation of the impact of selected aromatic compounds on consumer cognitive and affective processes as well as assessing the effectiveness of their implementation in food retail operations. At the end of the paper, we recommend options for the effective selection and implementation of aromatisation of different premises, by which the retailer can achieve not only a successful form of in-store communication, but also an increase the retail turnover of the store.

Sign in / Sign up

Export Citation Format

Share Document