Effect of alginate size, mannuronic/guluronic acid content and pH on particle size, thermodynamics and composition of complexes with β-lactoglobulin

Abstract This paper describes a rational design and testing of molecularly imprinted polymers (MIPs) as chiral stationary phases of thin-layer chromatography (TLC) for enantiomeric purity of naproxen. Using D-naproxen as template, MIPs with particle size between 10~90 μm were prepared by precipitation polymerization in acetonitrile/methanol mixed solvent. The interactions between functional monomers and template were verified by UV absorption spectrometry. The morphology, particle size distribution and specific surface area of MIPs were also observed by scanning electron microscopy, particle size distribution meter and liquid nitrogen adsorption instrument, respectively. Binding capacities of MIPs had been studied by equilibrium binding assay. Preparation conditions of TLC and impact of acetic acid content on the separation of enantiomers were investigated. The results indicated that when acetic acid content was 4%, the racemates of templates were completely separated, and the chiral separation factor α was 1.58.

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Metal Selectivity ofSargassumspp. and Their Alginates in Relation to Their α-l-Guluronic Acid Content and Conformation

Environmental Science & Technology ◽

10.1021/es025781d ◽

2003 ◽

Vol 37 (2) ◽

pp. 261-267 ◽

Cited By ~ 116

Author(s):

Thomas A. Davis ◽

Francisco Llanes ◽

Bohumil Volesky ◽

Alfonso Mucci

Keyword(s):

Acid Content ◽

Guluronic Acid ◽

Metal Selectivity

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Guluronic acid content as a factor affecting turbidity removal potential of alginate

Environmental Science and Pollution Research ◽

10.1007/s11356-016-7475-6 ◽

2016 ◽

Vol 23 (22) ◽

pp. 22568-22576 ◽

Cited By ~ 2

Author(s):

Çiğdem Kıvılcımdan Moral ◽

Helga Ertesvåg ◽

F. Dilek Sanin

Keyword(s):

Acid Content ◽

Turbidity Removal ◽

Guluronic Acid

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Influence of Chymosin on Physicochemical and Hydrolysis Characteristics of Casein Micelles and Individual Caseins

Nanomaterials ◽

10.3390/nano11102594 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2594

Author(s):

Chun-Chi Chen ◽

Liang-Yu Chen ◽

Wen-Tai Li ◽

Ken-Lin Chang ◽

Meng-I Kuo ◽

...

Keyword(s):

Particle Size ◽

Incubation Period ◽

Skim Milk ◽

Particle Size Analysis ◽

Supernatant Fraction ◽

Size Analysis ◽

Casein Micelles ◽

Molecular Weights ◽

Sds Page ◽

Β Lactoglobulin

The effects of chymosin on the physicochemical and hydrolysis characteristics of casein micelles and individual caseins were investigated. Adding 0.03 units of chymosin/mL led to the casein micelles in skim milk coagulating after a 3 h incubation period at 30 °C. SDS–PAGE investigation showed that β-CN, κ-CN, αs-CN, and a portion of β-lactoglobulin (β-LG) in the milk supernatant fraction (MSF) were precipitated into the milk pellet fraction (MPF). The mean particle size of the MSF with chymosin decreased from 254.4 nm to 179.2 nm after a 3 h incubation period. Mass spectrometry and SDS–PAGE analysis suggested that chymosin hydrolyzed individual β-CN, κ-CN, and αs-CN, but not β-LG. Chymosin hydrolysis led to a decrease in the molecular weights of the hydrolyzed β-CN, κ-CN, and αs-CN. Particle size analysis indicated that there was no difference in the particle size distribution of hydrolyzed β-CN and αs-CN. Moreover, our outcomes demonstrated that the hydrolysis of κ-CN by chymosin occurs before that of β-CN and αs-CN.

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Effect of particle size reduction, hydrothermal and fermentation treatments on phytic acid content and some physicochemical properties of wheat bran

Journal of Food Science and Technology ◽

10.1007/s13197-012-0802-0 ◽

2012 ◽

Vol 51 (10) ◽

pp. 2755-2761 ◽

Cited By ~ 17

Author(s):

Mahsa Majzoobi ◽

Safoora Pashangeh ◽

Asgar Farahnaky ◽

Mohammad Hadi Eskandari ◽

Jalal Jamalian

Keyword(s):

Particle Size ◽

Physicochemical Properties ◽

Phytic Acid ◽

Wheat Bran ◽

Acid Content ◽

Size Reduction ◽

Particle Size Reduction ◽

Phytic Acid Content ◽

Effect Of Particle Size

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Effect of Wheat Dietary Fiber Particle Size during Digestion In Vitro on Bile Acid, Faecal Bacteria and Short-Chain Fatty Acid Content

Plant Foods for Human Nutrition ◽

10.1007/s11130-016-0537-6 ◽

2016 ◽

Vol 71 (2) ◽

pp. 151-157 ◽

Cited By ~ 11

Author(s):

Krzysztof Dziedzic ◽

Artur Szwengiel ◽

Danuta Górecka ◽

Elżbieta Gujska ◽

Joanna Kaczkowska ◽

...

Keyword(s):

Particle Size ◽

Fatty Acid ◽

Bile Acid ◽

Dietary Fiber ◽

Acid Content ◽

Short Chain Fatty Acid ◽

Fatty Acid Content ◽

Chain Fatty Acid ◽

Faecal Bacteria

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Aqueous Enzymatic Extraction of Oil from Microwave-pretreated Jicaro Seeds

Current Biochemical Engineering ◽

10.2174/2212711906666190131150922 ◽

2019 ◽

Vol 5 (1) ◽

pp. 42-49

Author(s):

Brenda Yesenia Nolasco Arroyo ◽

Sandy Luz Ovando Chacón ◽

Veymar Guadalupe Tacias-Pascacio ◽

Guillermo Efrén Ovando Chacón ◽

Cristina Ventura Canseco ◽

...

Keyword(s):

Particle Size ◽

Fatty Acid ◽

Acid Content ◽

Fatty Acid Content ◽

Soxhlet Extraction ◽

Oil Yield ◽

Liquid Ratio ◽

Enzymatic Extraction ◽

Aqueous Enzymatic Extraction ◽

Solid Liquid

Background: Jicaro seeds can be considered oilseeds due to their high content of lipids, which could be used. Aqueous Enzymatic Extraction (AEE) of oils is a safe, economical and ecological technique, with the disadvantage that oil yields are lower than conventional methods. The microwaves pre-treatment of the seeds has been applied to overcome this inconvenience. Therefore, the objective of this study was to investigate the aqueous enzymatic extraction of oil from Jicaro seed pretreated in a microwave (M-AEE) compared to Soxhlet extraction, in terms of oil yield and its quality. Methods: M-AEE was evaluated varying type of enzyme, extraction time, enzyme concentration, solid/liquid ratio and particle size, according to Fractional Factorial experimental design. The obtained oil was analyzed in terms of fatty acid content and antioxidant activities. The same analyses were performed in oil obtained by Soxhlet extraction for comparison. Results: All parameters investigated in this work had a positive effect on the extraction process. The highest oil yield of 69.71% was obtained with a particle size of 0.59 mm, 3% (w/w) of Viscozyme L, solid/ liquid ratio of 1:6, and 5 h. No differences were found in fatty acid content and antioxidant activity between the oil obtained by M-AEE and that obtained by SE. Conclusion: The properties of the oil were not different in the two extraction methods evaluated; however, M-AEE has the advantage of being environmentally friendly technique. Jicaro seed oil physicochemical properties were similar to edible oils, thus could be considered as a new option of edible vegetable oil.

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Aggregation of β-lactoglobulin studied by in situ light scattering

Journal of Dairy Research ◽

10.1017/s0022029900031939 ◽

1996 ◽

Vol 63 (3) ◽

pp. 423-440 ◽

Cited By ~ 77

Author(s):

Marion A. M. Hoffmann ◽

Sebastianus P. F. M. Roefs ◽

Marleen Verheul ◽

Peter J. J. M. van Mil ◽

Kees G. De Kruif

Keyword(s):

Particle Size ◽

Light Scattering ◽

Kinetic Model ◽

Reaction Kinetic ◽

Salt Composition ◽

Effective Technique ◽

Reaction Constants ◽

Induced Aggregation ◽

Β Lactoglobulin

SummaryIn situ light scattering, where light scattered from a sample is measured directly while the sample is heated in the instrument, is presented as a simple and effective technique for studying the heat-induced aggregation of β-lactoglobulin. This technique was shown to be applicable not only to monitoring the initial aggregation steps, but to following the overall aggregation process with time. The experiments gave results similar to measurements carried out after a heat-quench treatment, but were more informative. From experiments on a standard NIZO β-lactoglobulin sample, a strongly desalted standard NIZO sample, different genetic variants of β-lactoglobulin and a mixture of these, we concluded that the standard NIZO sample was suitable for studying heat-induced aggregation. This sample has been investigated more extensively. Results with β-lactoglobulin (10–100 g/1) at 65 °C fitted a kinetic model for the denaturation and aggregation of β-lactoglobulin. This model, which held for β-lactoglobulin dissolved in water at near neutral pH and at 60–75 °C, recognizes an initiation, propagation and termination reaction, by analogy with polymer radical chemistry. It gave a quantitatively correct description of the dependence of the scattering intensity on the initial β-lactoglobulin concentration. Salt composition, pH and temperature strongly influenced the aggregation of β-lactoglobulin. Particle size increased with salt concentration in the range studied (up to 20 mM-NaCl and 1·0 mM-CaCl2). When the pH increased from 6°9 to 8·0 particle size was strongly reduced, whereas it strongly increased when pH was lowered to 6·2. Between 61·5 and 70 °C temperature did not affect particle size, whereas aggregation rate strongly increased. These effects could be incorporated in the kinetic model via the reaction constants of the reaction kinetic pathway.

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