scholarly journals Stability of immobilized biosorbent and its influence on biosorption of copper

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Dana Ivánová ◽  
Hedviga Horváthová ◽  
Jana Kaduková ◽  
Jana Kavuličová
Keyword(s):  
Copper Ions ◽  
Kinetic Studies ◽  
Alginate Beads ◽  
Swelling Behaviour ◽  
Acidic Solutions ◽  
Gel Beads ◽  
Basic Solutions ◽  
Immobilized Beads ◽  
Sodium And Potassium ◽  
Potential Use

Biomass immobilization in a polymeric matrix may improve biosorption capacity and facilitate the separation of biomass from metal-bearing solutions. Many polymers are studied as immobilizing agents for biosorption including biopolymers such as sodium alginate. In the article swelling behaviour of gel and dry beads has been studied in aqueous solutions with different acid-base character. Swelling of gel or dry calcium alginate beads was found in all acidic and basic solutions except of the gel beads in strong acidic solutions, which exhibited the tendency to shrink. Dry beads in diluted acidic solutions had the greatest stability because they exhibited minimum swelling. Dry and gel beads were completely dissolved in concentrated solutions of sodium and potassium hydroxides. The potential use of immobilized algal biomass in Ca-alginate beads for removal of copper ions from aqueous solution was also investigated. The results of the kinetic studies showed that the sorption of copper ions on gel immobilized beads are the most suitable.

A Dual Sensor for Biogenic Amines and Oxygen Based on Genipin Immobilized in Edible Calcium Alginate Gel Beads

2020 ◽  
Author(s):  
Ian Mallov ◽  
Fiona Jeeva ◽  
Chris Caputo
Keyword(s):  
Biogenic Amines ◽  
Calcium Alginate ◽  
Alginate Beads ◽  
Colorimetric Sensing ◽  
Naturally Occurring ◽  
Gel Beads ◽  
Dual Sensor ◽  
Calcium Alginate Gel ◽  
Toxic Food

Food is often wasted due to real or perceived concerns about preservation and shelf life. Thus, precise, accurate and consumer-friendly methods of indicating whether food is safe for consumers are drawing great interest. The colorimetric sensing of biogenic amines released as food degrades is a potential way of determining the quality of the food. Herein, we report the use of genipin, a naturally occurring iridoid, as a dual colorimetric sensor for both oxygen and biogenic amines. Immobilization of genipin in edible calcium alginate beads demonstrates that it is a capable sensor for amine vapors and can be immobilized in a non-toxic, food-friendly matrix.

Nitrification and Autotrophic Denitrification in Calcium Alginate Beads

1987 ◽  
Vol 19 (1-2) ◽  
pp. 175-182 ◽  
Author(s):  
Z. Lewandowski ◽  
R. Bakke ◽  
W. G. Characklis
Keyword(s):  
Calcium Carbonate ◽  
Calcium Ions ◽  
Continuous Flow ◽  
Calcium Alginate ◽  
Microbial Respiration ◽  
Flow System ◽  
Alginate Beads ◽  
Alginate Gel ◽  
Gel Beads ◽  
Calcium Alginate Gel

Immobilization of nitrifiers and autotrophic denitrifiers (Thiobacillus denitrificans) within calcium alginate gel was demonstrated. Calcium carbonate reagent was immobilized along with bacteria as the stabilizing agent. Protons released as a result of microbial respiration reacted with calcium carbonate producing calcium ions which internally stabilized the calcium alginate gel. The microbially active gel beads were mechanically stable and active for three months in a continuous flow system without addition of calcium.

Production of a bacteriocin active on lactate-fermenting clostridia byLactococcus lactissubsp.lactisimmobilized in coated alginate beads

1993 ◽  
Vol 60 (4) ◽  
pp. 581-591 ◽  
Author(s):  
Nicla Zezza ◽  
Gabriella Pasini ◽  
Angiolella Lombardi ◽  
Annick Mercenier ◽  
Paolo Spettoli ◽  
...  
Keyword(s):  
Immobilized Cells ◽  
Culture Media ◽  
Surrounding Medium ◽  
Free Cell ◽  
Alginate Beads ◽  
Cell System ◽  
Indicator Strain ◽  
Lactobacillus Delbrueckii ◽  
Gel Beads

SummaryWe report the isolation and immobilization of a nisinogenic strain (NZ1) ofLactococcus lactissubsp.lactis, active on gas-forming lactate-fermenting clostridia responsible for late blowing of Asiago and Montasio cheeses. The bacteriocin (nisin) produced by strain NZ1 is pronase-sensitive and is released in culture media during the growth phase. Using the sensitive indicator strainLactobacillus delbrueckiisubsp.bulgaricusNCDO 1489, a rapid microtitre plate based assay was developed for quantitative determination of the bacteriocin produced by NZ1 cells, either free or immobilized in gel beads. Scanning electron microscopy of cells immobilized in calcium alginate coated beads and viable counts of the surrounding medium showed that no cell leakage occurred during a 24 h assay. The bacteriocin released from immobilized cells reached, after 5 and 24 h, concentrations comparable to that of the free cell system after 3–4 h incubation in culture media.

Hydroxyapatite modified with silica used for sorption of copper(II)

2009 ◽  
Vol 63 (5) ◽  
Author(s):  
Erzsébet-Sára Bogya ◽  
Réka Barabás ◽  
Alexandra Csavdári ◽  
Valentina Dejeu ◽  
Ioan Bâldea
Keyword(s):  
Copper Ions ◽  
Copper Ion ◽  
Reaction Medium ◽  
Kinetic Studies ◽  
Sorption Process ◽  
Silica Content ◽  
Ion Concentration ◽  
X Ray Diffraction ◽  
Structural Modifications ◽  
Preparation Phase

AbstractThis paper aims to increase the sorption capacity of hydroxyapatite and to find the best apatite-based material for metal ions sorption. The sorption process of copper ions from water solutions by HAP and structurally modified HAP was carried out in this work. Structural modifications of HAP were realized in the preparation phase by an addition of sodium silica into the reaction medium. The prepared materials were characterized by physical-chemical methods: IR, electron-microscopy and X-ray diffraction. The composites characterized were tested in kinetic studies regarding ion exchange and adsorption of Cu2+. It was revealed that the silica content, particle size and initial copper ion concentration influence the process rate.

Biosorption of copper ions from aqueous solution using rape straw powders: Optimization, equilibrium and kinetic studies

2018 ◽  
Vol 150 ◽  
pp. 251-259 ◽  
Author(s):  
Xin Liu ◽  
Zhao-Qiong Chen ◽  
Bin Han ◽  
Chun-Li Su ◽  
Qin Han ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Copper Ions ◽  
Kinetic Studies ◽  
Rape Straw

scholarly journals Trinuclear copper biocatalytic center forms an active site of thiocyanate dehydrogenase

2020 ◽  
Vol 117 (10) ◽  
pp. 5280-5290 ◽  
Author(s):  
Tamara V. Tikhonova ◽  
Dimitry Y. Sorokin ◽  
Wilfred R. Hagen ◽  
Maria G. Khrenova ◽  
Gerard Muyzer ◽  
...  
Keyword(s):  
Active Site ◽  
Copper Ions ◽  
Soda Lakes ◽  
Three Dimensional ◽  
Kinetic Studies ◽  
Isosceles Triangle ◽  
Site Directed Mutagenesis ◽  
Paramagnetic Resonance ◽  
Mechanism Of Catalysis ◽  
Copper Center

Biocatalytic copper centers are generally involved in the activation and reduction of dioxygen, with only few exceptions known. Here we report the discovery and characterization of a previously undescribed copper center that forms the active site of a copper-containing enzyme thiocyanate dehydrogenase (suggested EC 1.8.2.7) that was purified from the haloalkaliphilic sulfur-oxidizing bacterium of the genus Thioalkalivibrio ubiquitous in saline alkaline soda lakes. The copper cluster is formed by three copper ions located at the corners of a near-isosceles triangle and facilitates a direct thiocyanate conversion into cyanate, elemental sulfur, and two reducing equivalents without involvement of molecular oxygen. A molecular mechanism of catalysis is suggested based on high-resolution three-dimensional structures, electron paramagnetic resonance (EPR) spectroscopy, quantum mechanics/molecular mechanics (QM/MM) simulations, kinetic studies, and the results of site-directed mutagenesis.

Subtraction of the Water Spectra from Infrared Spectra of Acidic and Alkaline Solutions

1998 ◽  
Vol 52 (7) ◽  
pp. 963-969 ◽  
Author(s):  
Jean-Joseph Max ◽  
Camille Chapados
Keyword(s):  
Infrared Spectra ◽  
Alkaline Solution ◽  
Malic Acid ◽  
Ir Spectrum ◽  
Pure Water ◽  
The Other ◽  
Alkaline Solutions ◽  
Acidic Solutions ◽  
Baseline Adjustment ◽  
Basic Solutions

The IR spectrum of a sample in acidic and alkaline solutions cannot be retrieved adequately when only the spectrum of pure water is subtracted. After such an operation, some water bands remain in the spectrum, which also has a distorted baseline. An analysis of a series of IR spectra of HCl and NaOH solutions showed that they could be represented by two pairs of eigenspectra, one pair for the acidic solutions and the other for the basic solutions. The fraction of each eigenspectrum of a sample in an acidic or alkaline solution is determined with the 2100 and 3300 cm−1 water bands. After subtraction, no baseline adjustment is necessary. The effectiveness of the method used to subtract the water bands is illustrated with solutions of malic acid at low and high pH.

Equilibrium and Kinetic Studies on Removal of Binary Metal Ions Using Immobilized Saccharomyces cerevisiae

2014 ◽  
Vol 661 ◽  
pp. 39-44
Author(s):  
Nur Khalida Adibah Md Rodzi ◽  
Senusi Faraziehan ◽  
Alrozi Rasyidah
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Metal Ions ◽  
Copper Ions ◽  
Binding Capacity ◽  
Kinetic Studies ◽  
Suitable Model ◽  
Zinc Ions ◽  
Copper And Zinc ◽  
Maximum Sorption ◽  
Pseudo Second Order

In this study, biosorption of copper and zinc ions on Baker’s yeast, Saccharomyces Cerevisiae was investigated. The data of batch experiments was used to perform equilibrium and kinetic studies. The experimental results were fitted well to the Langmuir and Freundlich model isotherms. According to the parameters of Langmuir isotherm, the maximum biosorption capacities of copper and zinc ions onto immobilized yeast were 5.408mg/g and 1.479mg/g at 293 Kfor the treated beads. Competitive biosorption of two metal ions was investigated in terms of maximum sorption quantity. The binding capacity for copper ions is more than the zinc ions for both untreated and treated immobilized yeast.While, for the kinetic studies, the pseudo second order model was found the most suitable model for the present systems.

scholarly journals Boron removal from aqueous solutions by a polyethylenimine-epichlorohydrin resin

2018 ◽  
Vol 83 (2) ◽  
pp. 251-264 ◽  
Author(s):  
Sofia Sarri ◽  
Panagiotis Misaelides ◽  
Dimitrios Zamboulis ◽  
Jolanta Warchoł
Keyword(s):  
Aqueous Solutions ◽  
Boron Concentration ◽  
Kinetic Studies ◽  
Alkaline Solutions ◽  
Competitive Sorption ◽  
Boron Removal ◽  
Boron Uptake ◽  
Acidic Solutions ◽  
Ph Values ◽  
Batch Technique

The use of a polyethylenimine?epichlorohydrin resin for the boron removal from aqueous solutions (boron concentration: 100?5000 mg L-1) of non-adjusted and pre-adjusted pH (pHnat, pHinit 8.0, 9.0 and 10.0) aqueous solutions was investigated using a batch technique. The boron concentration in the solutions after sorption was determined photometrically. The results indicated that the pH-dependent boron uptake was related to the protonation/deprotonation of the surface functional groups of the resin and to the boron speciation in solutions of different pH values. The maximum boron sorption capacity observed in solutions of pH 9.0 was 55 mg g-1 exceeding the majority of other commercial or alternative sorbents. Five empirical adsorption equations (Freundlich, Langmuir, Redlich?Peterson, Langmuir?Freundlich and Toth) were applied to the modelling of the boron adsorption equilibrium. The modelling results identified the homogenous boron sorption from acidic and heterogeneous from alkaline solutions. At alkaline pH, the system non-ideality can originate either from the different binding mechanism or from the competitive sorption of different boron species. The homogenous type boron sorption from acidic solutions was further confirmed by kinetic studies

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