scholarly journals New Insights into the Microbial Degradation of D-Cyphenothrin in Contaminated Water/Soil Environments

2020 ◽  
Vol 8 (4) ◽  
pp. 473 ◽  
Author(s):  
Yaohua Huang ◽  
Ziqiu Lin ◽  
Wenping Zhang ◽  
Shimei Pang ◽  
Pankaj Bhatt ◽  
...  
Keyword(s):  
Microbial Degradation ◽  
Environmental Contamination ◽  
Contaminated Soils ◽  
Culture Conditions ◽  
Synthetic Pyrethroids ◽  
Biochemical Basis ◽  
Benzenedicarboxylic Acid ◽  
Wide Range ◽  
Intermediate Metabolites ◽  
Uninoculated Control

Persistent use of the insecticide D-cyphenothrin has resulted in heavy environmental contamination and public concern. However, microbial degradation of D-cyphenothrin has never been investigated and the mechanism remains unknown. During this study, for the first time, an efficient D-cyphenothrin-degrading bacterial strain Staphylococcus succinus HLJ-10 was identified. Response surface methodology was successfully employed by using Box-Behnken design to optimize the culture conditions. At optimized conditions, over 90% degradation of D-cyphenothrin (50 mg·L−1) was achieved in a mineral salt medium within 7 d. Kinetics analysis revealed that its half-life was reduced by 61.2 d, in comparison with the uninoculated control. Eight intermediate metabolites were detected in the biodegradation pathway of D-cyphenothrin including cis-D-cyphenothrin, trans-D-cyphenothrin, 3-phenoxybenzaldehyde, α-hydroxy-3-phenoxy-benzeneacetonitrile, trans-2,2-dimethyl-3-propenyl-cyclopropanol, 2,2-dimethyl-3-propenyl-cyclopropionic acid, trans-2,2-dimethyl-3-propenyl-cyclopropionaldehyde, and 1,2-benzenedicarboxylic acid, dipropyl ester. This is the first report about the degradation of D-cyphenothrin through cleavage of carboxylester linkage and diaryl bond. In addition to degradation of D-cyphenothrin, strain HLJ-10 effectively degraded a wide range of synthetic pyrethroids including permethrin, tetramethrin, bifenthrin, allethrin, and chlorempenthrin, which are also widely used insecticides with environmental contamination problems. Bioaugmentation of D-cyphenothrin-contaminated soils with strain HLJ-10 substantially enhanced its degradation and over 72% of D-phenothrin was removed from soils within 40 d. These findings unveil the biochemical basis of a highly efficient D-cyphenothrin-degrading bacterial isolate and provide potent agents for eliminating environmental residues of pyrethroids.

scholarly journals Biodegradation of Allethrin by a Novel Fungus Fusarium proliferatum Strain CF2, Isolated from Contaminated Soils

2020 ◽  
Vol 8 (4) ◽  
pp. 593 ◽  
Author(s):  
Pankaj Bhatt ◽  
Wenping Zhang ◽  
Ziqiu Lin ◽  
Shimei Pang ◽  
Yaohua Huang ◽  
...  
Keyword(s):  
Microbial Degradation ◽  
Contaminated Soils ◽  
Degradation Kinetics ◽  
Fusarium Proliferatum ◽  
Minimal Salt Medium ◽  
Optimum Conditions ◽  
Uninoculated Control ◽  
High Concentrations ◽  
Continuous Use ◽  
Kinetics Of

Continuous use of allethrin has resulted in heavy environmental contamination and has raised public concern about its impact on human health, yet little is known about the kinetics and microbial degradation of this pesticide. This study reported the degradation kinetics in a novel fungal strain, Fusarium proliferatum CF2, isolated from contaminated agricultural fields. Strain CF2 utilized 50 mg·L−1 of allethrin as the sole carbon source for growth in minimal salt medium and tolerated high concentrations of allethrin of up to 1000 mg·L−1. The optimum degradation conditions for strain CF2 were determined to be a temperature of 26 °C and pH 6.0 using response surface methodology. Under optimum conditions, strain CF2 completely degraded allethrin within 144 hours. The degradation kinetics of allethrin followed first order reaction kinetics. Kinetics analysis showed that its half-life was substantially reduced by 507.1 hours, as compared to the uninoculated control. This study provides new insights into the microbial degradation of allethrin with fungal F. proliferatum CF2.

scholarly journals Native Plant Capacity for Gentle Remediation in Heavily Polluted Mines

2021 ◽  
Vol 11 (4) ◽  
pp. 1769
Author(s):  
María Noelia Jiménez ◽  
Gianluigi Bacchetta ◽  
Francisco Bruno Navarro ◽  
Mauro Casti ◽  
Emilia Fernández-Ondoño
Keyword(s):  
Trace Elements ◽  
Plant Species ◽  
Contaminated Soils ◽  
Aerial Part ◽  
Bioaccumulation Factor ◽  
Native Plant ◽  
Dittrichia Viscosa ◽  
Wide Range ◽  
Cistus Salviifolius ◽  
Plant Capacity

The use of plant species to stabilize and accumulate trace elements in contaminated soils is considered of great usefulness given the difficulty of decontaminating large areas subjected to mining for long periods. In this work, the bioaccumulation of trace elements is studied by relating the concentrations in leaves and roots of three plants of Mediterranean distribution (Dittrichia viscosa, Cistus salviifolius, Euphorbia pithyusa subsp. cupanii) with the concentrations of trace elements in contaminated and uncontaminated soils. Furthermore, in the case of D. viscosa, to know the concentration of each element by biomass, the pool of trace elements was determined both in the aerial part and in the roots. The bioaccumulation factor was not high enough in any of the species studied to be considered as phytoextractors. However, species like the ones studied in this work that live on soils with a wide range of concentration of trace elements and that develop a considerable biomass could be considered for stabilization of contaminated soils. The plant species studied in this work are good candidates for gentle-remediation options in the polluted Mediterranean.

scholarly journals Activation of the receptor tyrosine kinase RET improves long-term hematopoietic stem cell outgrowth and potency

Blood ◽  
2020 ◽  
Vol 136 (22) ◽  
pp. 2535-2547 ◽  
Author(s):  
W. Grey ◽  
R. Chauhan ◽  
M. Piganeau ◽  
H. Huerga Encabo ◽  
M. Garcia-Albornoz ◽  
...  
Keyword(s):  
Intracellular Signaling ◽  
Culture Conditions ◽  
Cellular Growth ◽  
Great Promise ◽  
Bone Marrow Niche ◽  
Hematopoietic Stem ◽  
Intracellular Signaling Pathway ◽  
Wide Range

Abstract Expansion of human hematopoietic stem cells (HSCs) is a rapidly advancing field showing great promise for clinical applications. Recent evidence has implicated the nervous system and glial family ligands (GFLs) as potential drivers of hematopoietic survival and self-renewal in the bone marrow niche; how to apply this process to HSC maintenance and expansion has yet to be explored. We show a role for the GFL receptor, RET, at the cell surface of HSCs in mediating sustained cellular growth, resistance to stress, and improved cell survival throughout in vitro expansion. HSCs treated with the key RET ligand/coreceptor complex, glial-derived neurotrophic factor and its coreceptor, exhibit improved progenitor function at primary transplantation and improved long-term HSC function at secondary transplantation. Finally, we show that RET drives a multifaceted intracellular signaling pathway, including key signaling intermediates protein kinase B, extracellular signal-regulated kinase 1/2, NF-κB, and p53, responsible for a wide range of cellular and genetic responses that improve cell growth and survival under culture conditions.

scholarly journals Quantitative analysis of tumour spheroid structure

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alexander P Browning ◽  
Jesse A Sharp ◽  
Ryan J Murphy ◽  
Gency Gunasingh ◽  
Brodie Lawson ◽  
...  
Keyword(s):  
Cell Lines ◽  
Tumour Microenvironment ◽  
Culture Conditions ◽  
Experimental Models ◽  
Seeding Density ◽  
Modelling Framework ◽  
Tumour Spheroid ◽  
Tumour Spheroids ◽  
Wide Range

Tumour spheroids are common in vitro experimental models of avascular tumour growth. Compared with traditional two-dimensional culture, tumour spheroids more closely mimic the avascular tumour microenvironment where spatial differences in nutrient availability strongly influence growth. We show that spheroids initiated using significantly different numbers of cells grow to similar limiting sizes, suggesting that avascular tumours have a limiting structure; in agreement with untested predictions of classical mathematical models of tumour spheroids. We develop a novel mathematical and statistical framework to study the structure of tumour spheroids seeded from cells transduced with fluorescent cell cycle indicators, enabling us to discriminate between arrested and cycling cells and identify an arrested region. Our analysis shows that transient spheroid structure is independent of initial spheroid size, and the limiting structure can be independent of seeding density. Standard experimental protocols compare spheroid size as a function of time; however, our analysis suggests that comparing spheroid structure as a function of overall size produces results that are relatively insensitive to variability in spheroid size. Our experimental observations are made using two melanoma cell lines, but our modelling framework applies across a wide range of spheroid culture conditions and cell lines.

scholarly journals Plasticity in Escherichia coli cell wall metabolism promotes fitness and mediates intrinsic antibiotic resistance across environmental conditions

2018 ◽  
Author(s):  
Elizabeth A Mueller ◽  
Petra Anne Levin
Keyword(s):  
Escherichia Coli ◽  
Cell Wall ◽  
Growth Parameter ◽  
Culture Conditions ◽  
Cell Wall Integrity ◽  
Bacterial Cells ◽  
Intrinsic Resistance ◽  
Wide Range ◽  
Peptidoglycan Cell Wall ◽  
Wide Ph Range

ABSTRACTAlthough the peptidoglycan cell wall is an essential structural and morphological feature of most bacterial cells, the extracytoplasmic enzymes involved in its synthesis are frequently dispensable under standard culture conditions. By modulating a single growth parameter—extracellular pH—we discovered a subset of these so-called “redundant” enzymes in Escherichia coli are required for maximal fitness across pH environments. Among these pH specialists are the class A penicillin binding proteins PBP1 a and PBP1 b; defects in these enzymes attenuate growth in alkaline and acidic conditions, respectively. Genetic, biochemical, and cytological studies demonstrate that synthase activity is required for cell wall integrity across a wide pH range, and differential activity across pH environments significantly alters intrinsic resistance to cell wall active antibiotics. Together, our findings reveal previously thought to be redundant enzymes are instead specialized for distinct environmental niches, thereby ensuring robust growth and cell wall integrity in a wide range of conditions.

In situ multiphase fluidization ("upflow washing") for the remediation of hydrocarbon contaminated sands

1998 ◽  
Vol 35 (6) ◽  
pp. 938-960 ◽  
Author(s):  
Robert K Niven ◽  
Nasser Khalili
Keyword(s):  
Theoretical Analysis ◽  
Contaminated Soils ◽  
Fixed Bed ◽  
Fine Sand ◽  
In Situ Remediation ◽  
Pump And Treat ◽  
Wide Range ◽  
Phase Liquid ◽  
Regime Map

A new in situ remediation method is described, "upflow washing," in which contaminants are flushed to the surface within an in situ fluidized zone produced by a jet inserted into a granular formation. The suitability of the method for LNAPL (light non-aqueous phase liquid) remediation is examined by experiments on diesel-contaminated soils within column and tank settings. The experiments indicate significant reductions in diesel levels (96-99.9%) may be achieved by fluidization with water and gas (gas-liquid upflow washing, GLUW) for a wide range of initial diesel concentrations (10 000 to 150 000 mg/kg) and for soil fines contents of 0 to at least 10%. Final diesel levels of <1000 mg/kg in a uniform fine sand and <200 mg/kg in clayey sands can be achieved. The efficiency is much higher than that of fixed bed flushing (simulated pump-and-treat), as the method overcomes the trapping of NAPL ganglia. Fludization with water alone (liquid upflow washing, LUW) is less effective than fixed bed flushing in the uniform sand, but approaches that of GLUW in clayey and silty sands. The results are explained by theoretical analysis of the removability of isolated NAPL droplets and mixed solid - NAPL particles from a fluidized bed due to buoyancy and elutriation, which may be represented using a "removability regime map" for the diesel-water-sand system.Key words: fluidization, in situ, remediation, NAPL, diesel.

Age-specific different immune responses due to capabilities of secreting primal immunoglobulins responding to unexperienced antigens

2021 ◽  
Author(s):  
JANGHO LEE ◽  
Kyoungshik Cho ◽  
Hyejin Kook ◽  
Suman Kang ◽  
Yunsung Lee ◽  
...  
Keyword(s):  
Stem Cells ◽  
Immune System ◽  
Defense Mechanism ◽  
Ex Vivo ◽  
Binding Capacity ◽  
Culture Conditions ◽  
Fetal Stem Cells ◽  
Self Defense ◽  
Wide Range ◽  
Ex Vivo Culture

Abstract Among numerous studies on COVID-19, we noted that the infection and mortality rates of SARS-CoV-2 increased with age and that fetuses known to be particularly susceptible to infection were better protected despite various mutations. Hence, we established the hypothesis that a new immune system exists that forms before birth and decreases with aging. To prove this, we analyzed the components from early pregnancy fetal stem cells cultivated in various ex-vivo culture conditions simulating the environment during pregnancy. Resultingly, we confirmed that IgM, a natural antibody produced only in early B-1 cells, immunoglobulins including IgG3, which has a wide range of antigen-binding capacity and affinity, complement proteins, and antiviral proteins are induced. Our results suggest that fetal stem cells can form an independent immune system responding to unlearned antigens as a self-defense mechanism before establishing mature immune systems. Moreover, we propose the possibility of new solutions to cope with various infectious diseases based on the factors therein.

Embryonic and larval development of the caridean shrimp Palaemon argentinus (Decapoda, Caridea): effects of salinity and diet

Crustaceana ◽  
2021 ◽  
Vol 94 (1) ◽  
pp. 45-62
Author(s):  
Carolina Tropea ◽  
Liane Stumpf ◽  
Laura S. López Greco
Keyword(s):  
Larval Development ◽  
Artemia Salina ◽  
Culture Conditions ◽  
Nutritional Requirements ◽  
Larval Performance ◽  
Larval Rearing ◽  
Caridean Shrimp ◽  
Natural Habitats ◽  
Larval Stages ◽  
Wide Range

Abstract The caridean shrimp Palaemon argentinus is a species of commercial and ecological interest. Its numerous larval stages, the lack of knowledge on their nutritional requirements, and their ability to survive in a wide range of salinities raise questions on the optimum conditions for larval rearing in captivity. The present study was aimed at evaluating embryonic development under different salinities and larval development under different combinations of salinities and diet regimes, in order to define alternative, cheaper culture conditions. We tested salinities usually encountered by the species in natural habitats (0.1, 1 and 5 ppt) and a highly protein-inert diet (Tetracolor®) as a potential replacement for live food (nauplii of Artemia salina). The incubation period and fecundity were similar among salinity treatments. Overall, the number of survival days and percentage of zoeae that moulted two, three and four times were higher when embryogenesis occurred at 5 ppt and when larvae were exposed to 5 ppt. These results suggest that the conditions experienced by embryos affect the performance of the first larval stages, and probably reflect the lower energetic requirements of zoeae to osmoregulate as water and haemolymph osmolarity become closer. On the other hand, larval performance was better when fed A. salina nauplii than Tetracolor®. The latter may not cover the nutritional requirements of zoeae or may have low digestibility due to insufficient enzymes in the undeveloped larval digestive system. Based on the present results, we conclude that a salinity of 5 ppt combined with a diet consisting of Artemia sp. nauplii is optimal for larval culture at early stages.

Liquid Chromatographic Method for Determination of Extractable Nitroaromatic and Nitramine Residues in Soil

1989 ◽  
Vol 72 (6) ◽  
pp. 890-899 ◽  
Author(s):  
Thomas F Jenkins ◽  
Mariannee Walsh ◽  
Patricia W Schumacher ◽  
Paul H Miyares ◽  
Christopher F Bauer ◽  
...  
Keyword(s):  
Contaminated Soils ◽  
Extraction Methods ◽  
Ease Of Use ◽  
Linear Calibration ◽  
Soil Extracts ◽  
Spiked Soil ◽  
Collaborative Test ◽  
Wide Range ◽  
Working Standards ◽  
Liquid Chromatographic

Abstract An analytical method was developed to determine the concentration of nitroaromatic and nitramine residues in soil. Air-dried soil samples are ground with a mortar and pestle and extracted with acetonitrile in an ultrasonic bath. A portion of extract is diluted with aqueous CaCh to flocculate suspended particles, filtered, and analyzed by liquid chromatography. The method provides linear calibration curves over a wide range of concentration. Detection limits ranged from 0.03 to 1.27 ng/g. Recovery of spiked analyte was better than 80% for all analytes tested. Each step in the analytical procedure was optimized using spiked and field-contaminated soils. This optimization included tests to (1) assess the effectiveness and kinetics associated with various extraction methods, solvents, and soil-to-solvent ratios; (2) compare separations achievable using various combinations of reverse-phase columns and eluants; (3) assess analyte recovery and ease of use for various procedures to remove particles from extracts; and (4) document stability of soil extracts and analytical stock and working standards. A ruggedness test and a preliminary assessment at 2 other laboratories indicated that the method was sufficiently rugged to justify a full-scale collaborative test. A comparison of extraction kinetics for spiked soil vs field-contaminated soil revealed very different kinetic behavior, indicating it is unwise to develop extraction procedures based solely on spiked soils.

Conceivable Bioremediation Techniques Based on Quorum Sensing

2013 ◽  
Vol 295-298 ◽  
pp. 39-44 ◽  
Author(s):  
Nan Qing Liao ◽  
Hao Ming Li
Keyword(s):  
Heavy Metal ◽  
Quorum Sensing ◽  
Contaminated Soils ◽  
Genetic Basis ◽  
Cellular Communication ◽  
Cellular Systems ◽  
Reversible Process ◽  
Wide Range

Quorum sensing(QS) is a mechanism of microbes to coordinate their activities, which allows them to function as multi-cellular systems. Recently, many researches have proved that the engineered QS system have a wide range of applications such as bioremediation of oil and heavy metal contaminated soils, and prevention of biofouling. Here we review the function of QS signals produced by bacteria, and the principle of enhancing degradative capacities of microbe. Specifically, we describe how QS system regulate the formation and dispersion of biofilms, which are reversible process that biofilms may be generated and removed as desired. The development of strategies to disrupt and manipulate QS are also implicated. Cells can be engineered to secrete QS signals to affect the behavior of neighboring cells in a consortium via engineered cellular communication. The complete genetic basis of QS may be used to control these communities of associated cells for bioremediation applications.

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