scholarly journals Insights into the Restoration of Tributyltin Contaminated Environments Using Marine Bacteria from Portuguese Fishing Ports

2021 ◽  
Vol 11 (14) ◽  
pp. 6411
Author(s):  
Hugo R. Monteiro ◽  
Ariana B. Moutinho ◽  
Maria J. Campos ◽  
Ana C. Esteves ◽  
Marco F. L. Lemos
Keyword(s):  
Marine Bacteria ◽  
Degradation Products ◽  
Parent Compound ◽  
Model Organism ◽  
Degradation Process ◽  
Transformation Products ◽  
Antifouling Paints ◽  
Degrading Bacteria ◽  
Ecotoxicological Assays

Tributyltin (TBT) is an organotin chemical mainly used as biocide in marine antifouling paints. Despite the restrictions and prohibitions on its use, TBT is still an environmental problem due to its extensive application and subsequent release into the environment, being regarded as one of the most toxic chemicals released into the marine ecosystems. Microorganisms inhabiting impacted sites are crucial for their restoration since they have developed mechanisms to tolerate and break down pollutants. Nonetheless, transformation products resulting from the degradation process may still be toxic or, sometimes, even more toxic than the parent compound. The determination of the parent and degradation products by analytical methods, although necessary, may not be ecologically relevant since no information is provided regarding their ecotoxicity. In this study, marine bacteria collected from seven Portuguese fishing ports were isolated and grown in the presence of TBT. Bacteria that exhibited higher growth were used to bioremediate TBT-contaminated waters. The potential of these bacteria as bioremediation agents was evaluated through ecotoxicological assays using the sea snail Gibbula umbilicalis as model organism. Data suggested that some TBT-tolerant bacteria, such as Pseudomonas putida, can reduce the toxicity of TBT contaminated environments. This work contributes to the knowledge of TBT-degrading bacteria.

Genomic insights from Monoglobus pectinilyticus: a pectin-degrading specialist bacterium in the human colon

2020 ◽  
Author(s):  
CC Kim ◽  
GR Healey ◽  
WJ Kelly ◽  
ML Patchett ◽  
Z Jordens ◽  
...  
Keyword(s):  
Cell Surface ◽  
Degradation Products ◽  
Model Organism ◽  
Human Colon ◽  
Surface Proteins ◽  
Human Gut ◽  
Pectate Lyases ◽  
Unusual Distribution ◽  
Degrading Bacteria ◽  
Acetyl Esterases

© 2019, International Society for Microbial Ecology. Pectin is abundant in modern day diets, as it comprises the middle lamellae and one-third of the dry carbohydrate weight of fruit and vegetable cell walls. Currently there is no specialized model organism for studying pectin fermentation in the human colon, as our collective understanding is informed by versatile glycan-degrading bacteria rather than by specialist pectin degraders. Here we show that the genome of Monoglobus pectinilyticus possesses a highly specialized glycobiome for pectin degradation, unique amongst Firmicutes known to be in the human gut. Its genome encodes a simple set of metabolic pathways relevant to pectin sugar utilization, and its predicted glycobiome comprises an unusual distribution of carbohydrate-active enzymes (CAZymes) with numerous extracellular methyl/acetyl esterases and pectate lyases. We predict the M. pectinilyticus degradative process is facilitated by cell-surface S-layer homology (SLH) domain-containing proteins, which proteomics analysis shows are differentially expressed in response to pectin. Some of these abundant cell surface proteins of M. pectinilyticus share unique modular organizations rarely observed in human gut bacteria, featuring pectin-specific CAZyme domains and the cell wall-anchoring SLH motifs. We observed M. pectinilyticus degrades various pectins, RG-I, and galactan to produce polysaccharide degradation products (PDPs) which are presumably shared with other inhabitants of the human gut microbiome (HGM). This strain occupies a new ecological niche for a primary degrader specialized in foraging a habitually consumed plant glycan, thereby enriching our understanding of the diverse community profile of the HGM.

scholarly journals ESTUDO DE ESTABILIDADE DO FOSFATO DISSÓDICO DE PREDNISOLONA EM CONDIÇÕES DE ESTRESSE OXIDATIVO E TÉRMICO, EM FORMULAÇÃO ORAL

2018 ◽  
Vol 35 (4) ◽  
pp. 09
Author(s):  
Cleber Antonio Lindino ◽  
Marcia Lina Mitsui ◽  
Rodolfo Ortiguara ◽  
Daiane Felin ◽  
Mauricio Ferreira Da Rosa ◽  
...  
Keyword(s):  
High Performance ◽  
Dosage Form ◽  
Degradation Products ◽  
Degradation Process ◽  
Oral Solution ◽  
Form Solution ◽  
Oral Dosage ◽  
First Order ◽  
First Order Kinetics

This work was to investigate the process of degradation of the drug Prednisolone Sodium Phosphate (FSP) in oral solution dosage form through the degradation experiments, evaluating the parameters in accordance with Resolution 899/2003 ANVISA and the degradation process of the drug. The method by high performance liquid chromatography (HPLC) developed for the determination of the drug was validated to demonstrate its applicability as an indicator of stability, ensuring reliability. After the method be validated to study the degradation of the drug, it was shown that drastic conditions of oxidative stress (H O 30%) and 2 2 temperature 60°C, the degradation of the drug is dependent on its concentration (first order kinetics). The results were  satisfactory, showing that this method is suitable to investigate the formation of degradation products in oral dosage form solution

scholarly journals Validated Column High-Performance Liquid Chromatographic Method for Determination of Aspirin and Clopidogrel in Combined Tablets in the Presence of Degradation Products Formed Under ICHRecommended Stress Conditions

2009 ◽  
Vol 92 (1) ◽  
pp. 152-157 ◽  
Author(s):  
Pankaj K Kachhadia ◽  
Ashish S Doshi ◽  
Hitendra S Joshi
Keyword(s):  
High Performance ◽  
Degradation Products ◽  
Parent Compound ◽  
High Performance Liquid Chromatographic ◽  
Stress Conditions ◽  
Assay Method ◽  
Forced Degradation ◽  
Relative Standard ◽  
Liquid Chromatographic

Abstract The development and validation of a column high-performance liquid chromatographic assay method for the determination of aspirin and clopidogrel in tablet formulation are described. The combination formulation was subjected to International Conference on Harmonization-recommended stress conditions. Separation of the drugs from the degradation products formed under stress conditions was achieved on an octasilyl (C8) column using 0.3 orthophosphoric acidacetonitrile (65 + 35, v/v) mobile phase. The method was validated for specificity, linearity, limits of detection and quantification, precision, accuracy, and robustness. The method was found to be specific against placebo interference and during the forced degradation. The response was linear in the concentration range of 30.0120.0 g/mL for aspirin and 15.060.0 g/mL for clopidogrel, with a correlation coefficient of 0.9999 for both. The relative standard deviation values for intra- and interday precision were <2.0. The accuracy was between 99.12 and 99.83 for aspirin and 98.20 and 100.35 for clopidogrel. Stress testing showed degradation products that were well-separated from the parent compound, confirming the stability-indicating capacity of the method.

Stability Study and Kinetic Monitoring of Cefquinome Sulfate Using Cyclodextrin-Based Ion-Selective Electrode: Application to Biological Samples

2016 ◽  
Vol 99 (1) ◽  
pp. 73-81 ◽  
Author(s):  
Ali M Yehia ◽  
Reham M Arafa ◽  
Samah S Abbas ◽  
Sawsan M Amer
Keyword(s):  
Degradation Products ◽  
Biological Fluids ◽  
Accurate Determination ◽  
Pharmaceutical Formulations ◽  
Degradation Process ◽  
Reversed Phase ◽  
Stability Study ◽  
Spiked Plasma ◽  
Dibutyl Sebacate

Abstract Two novel cefquinome sulfate (CFQ)-selective electrodes were performed with dibutyl sebacate as a plasticizer using a polymeric matrix of polyvinyl chloride. Sensor 1 was prepared using sodium tetraphenylborate as a cation exchanger without incorporation of ionophore, whereas 2-hydroxy propyl β-cyclodextrin was used as ionophore in sensor 2. A stable, reliable, and linear response was obtained in concentration ranges 3.2 × 10−5 to 1 × 10−2 mol/L and 1 × 10−5 to 1 × 10−2 mol/L for sensors 1 and 2, respectively. Both sensors could be sufficiently applied for quantitative determination of CFQ in the presence of degradation products either in bulk powder or in pharmaceutical formulations. Sensor 2 provided better selectivity and sensitivity, wider linearity range, and higher performance. Therefore it was used successfully for accurate determination of CFQ in biological fluids such as spiked plasma and milk samples. Furthermore, an online kinetic study was applied to the CFQ alkaline degradation process to estimate the reaction rate and half-life with feasible real-time monitoring. The developed sensors were found to be fast, accurate, sensitive, and precise compared with the manufacturer's reversed-phase chromatographic method.

Genomic insights from Monoglobus pectinilyticus: a pectin-degrading specialist bacterium in the human colon

2020 ◽  
Author(s):  
CC Kim ◽  
GR Healey ◽  
WJ Kelly ◽  
ML Patchett ◽  
Z Jordens ◽  
...  
Keyword(s):  
Cell Surface ◽  
Degradation Products ◽  
Model Organism ◽  
Human Colon ◽  
Surface Proteins ◽  
Human Gut ◽  
Pectate Lyases ◽  
Unusual Distribution ◽  
Degrading Bacteria ◽  
Acetyl Esterases

© 2019, International Society for Microbial Ecology. Pectin is abundant in modern day diets, as it comprises the middle lamellae and one-third of the dry carbohydrate weight of fruit and vegetable cell walls. Currently there is no specialized model organism for studying pectin fermentation in the human colon, as our collective understanding is informed by versatile glycan-degrading bacteria rather than by specialist pectin degraders. Here we show that the genome of Monoglobus pectinilyticus possesses a highly specialized glycobiome for pectin degradation, unique amongst Firmicutes known to be in the human gut. Its genome encodes a simple set of metabolic pathways relevant to pectin sugar utilization, and its predicted glycobiome comprises an unusual distribution of carbohydrate-active enzymes (CAZymes) with numerous extracellular methyl/acetyl esterases and pectate lyases. We predict the M. pectinilyticus degradative process is facilitated by cell-surface S-layer homology (SLH) domain-containing proteins, which proteomics analysis shows are differentially expressed in response to pectin. Some of these abundant cell surface proteins of M. pectinilyticus share unique modular organizations rarely observed in human gut bacteria, featuring pectin-specific CAZyme domains and the cell wall-anchoring SLH motifs. We observed M. pectinilyticus degrades various pectins, RG-I, and galactan to produce polysaccharide degradation products (PDPs) which are presumably shared with other inhabitants of the human gut microbiome (HGM). This strain occupies a new ecological niche for a primary degrader specialized in foraging a habitually consumed plant glycan, thereby enriching our understanding of the diverse community profile of the HGM.

scholarly journals Quantitative analysis of Loperamide hydrochloride in the presence its acid degradation products

2009 ◽  
Vol 63 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Ivana Savic ◽  
Goran Nikolic ◽  
Ivan Savic ◽  
Valentina Marinkovic
Keyword(s):  
Mobile Phase ◽  
Degradation Products ◽  
Rapid Determination ◽  
Parent Compound ◽  
Ammonium Hydroxide ◽  
High Sensitivity ◽  
Hplc Method ◽  
Pharmaceutical Formulation ◽  
Acid Degradation

The aim of this work was to develop a new RP-HPLC method for the determination of loperamide hydrochloride in the presence of its acid degradation products. Separation of loperamide from degradation products was performed using ZORBAX Eclipse XDB C-18, column with a mobile phase consisting of 0.1% sodium-octansulphonate, 0.05% triethylamine, 0.1% ammonium hydroxide in water:acetonitrile (45:55 v/v). The mobile phase was adjusted to pH 3.2 with phosphoric acid. The method showed high sensitivity with good linearity over the concentration range of 10 to 100 ?g cm-3. The method was successfully applied to the analysis of a pharmaceutical formulation (Loperamide, Zdravlje-Actavis, Serbia) containing loperamide hydrochloride with excellent recovery. The loperamide hydrochloride degradation during acid hydrolysis and kinetics investigation was carried out in hydrochloric acid solutions of 0.1, 1.0 and 1.5 mol dm-3, at different temperatures (25 and 40?C), by monitoring the parent compound itself. The first order reaction of loperamide degradation in acid solution was determined. The activation energy was estimated from the Arrhenius plot and it was found to be 38.81 kJ mol-1 at 40?C. The developed procedure was successfully applied for the rapid determination of loperamide hydrochloride in pharmaceutical formulation (Loperamide, Zdravlje-Actavis, Serbia) and in the presence of its acid degradation products.

scholarly journals A Validated RP-HPLC Method and Force Degradation Studies of Fexofenadine Hydrochloride in Pharmaceutical Dosage Form

2018 ◽  
Vol 17 (1) ◽  
pp. 43-50
Author(s):  
Sherejad Sanam ◽  
Sharmin Nahar ◽  
Nazmus Saqueeb ◽  
SM Abdur Rahman
Keyword(s):  
Flow Rate ◽  
Mobile Phase ◽  
Limit Of Detection ◽  
Degradation Products ◽  
Parent Compound ◽  
Hplc Method ◽  
Pharmaceutical Dosage Form ◽  
Rp Hplc ◽  
Fexofenadine Hcl

A stability indicating HPLC method was developed and validated for the quantitative determination of fexofenadine hydrochloride. An isocratic separation was achieved using phenomenex (C18) column (250×4.6 mm, 5 μm) with flow rate of 1.0 ml/min and UV detection at 254 nm. The mobile phase consists of 5Mm acetate buffer: acetonitrile (50:50; v/v) with pH 9.4 adjusted with acetic acid. The drug was subjected to oxidative, acidic, basic, neutral, photolytic and thermal degradation. All degradation products were eluted in an overall analytical run time of approximately 40 min with the parent compound fexofenadine hydrochloride at a flow rate of approximately 3.3±0.3 min. The method was linear over the concentration range of 31.5-500 μg/ml (r2 = 0.999) with limit of detection and quantification of 3.5 μg/ml and 10.1 μg/ml, respectively. The method has the requisite accuracy, selective, precision and robustness to assay fexofenadine HCl in tablets.Dhaka Univ. J. Pharm. Sci. 17(1): 43-50, 2018 (June)

scholarly journals Stability Indicating RP-HPLC Method for Estimation of Fexofenadine Hydrochloride in Pharmaceutical Formulation

2012 ◽  
Vol 9 (3) ◽  
pp. 1257-1265 ◽  
Author(s):  
H. M. Nimje ◽  
Shital T. Nimje ◽  
R. J. Oswal ◽  
S. T. Bhamre
Keyword(s):  
Limit Of Detection ◽  
Degradation Products ◽  
Parent Compound ◽  
Hplc Method ◽  
Uv Detector ◽  
Oxidation Condition ◽  
Stability Indicating ◽  
Stress Studies ◽  
Tablet Dosage

A stability-indicating HPLC method was developed and validated for the quantitative determination of fexofenadine in tablet dosage forms. An isocratic seperation was achieved using a Zorbax, Eclipse XBD, C-8 Column having 150 x 4.6 mm i.d., 5 µm particle size column with flow rate of 1.2 ml/min and using UV detector to monitor the eluate at 210 nm. The mobile phase consist of phosphate buffer: acetonitrile: methanol (60:20:20; v/v/v) with pH 3.7 adjusted with o-phosphoric acid. The drug was subjected to oxidation, hydrolysis, photolysis and thermal degradation. Fexofenadine was found to degrate in acidic, basic and oxidation condition. Complete seperation of degraded product was achieved from parent compound. All degradation products in an overall analytical run time of approximately 60 min with the parent compound fexofenadine eluting at approximately 12.1 ±0.9 min. The method was linear over the concentration range of 1-100 µg/ml (r2= 0.9970) with limit of detection and quatification of 0.2 µg/ml and 0.6 µg/ml, respectively. The method has the requisite accuracy, selectivity, sencitivity, precision and robustness to assay fexofenadine in tablets. Degradation products resulting from stress studies did not interfere with the detection of fexofenadine and the assay is thus stability indicating.

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