An optimized approach to recovering O/W interfacial myofibrillar protein: Emphasizing on interface-induced structural changes

2022 ◽  
Vol 124 ◽  
pp. 107194
Author(s):  
Weiyi Zhang ◽  
Junmeng Lu ◽  
Xue Zhao ◽  
Xinglian Xu
Keyword(s):  
Structural Changes ◽  
Myofibrillar Protein

scholarly journals Physical Properties and Structural Changes of Myofibrillar Protein Gels Prepared with Basil Seed Gum at Different Salt Levels and Application to Sausages

Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 702
Author(s):  
Chang Hoon Lee ◽  
Koo Bok Chin
Keyword(s):  
Physical Properties ◽  
Structural Changes ◽  
Surface Hydrophobicity ◽  
Myofibrillar Protein ◽  
Protein Surface ◽  
Salt Level ◽  
Low Salt ◽  
Protein Surface Hydrophobicity ◽  
Protein Gels ◽  
Seed Gum

The objective of this study was to evaluate physical properties and structural changes of myofibrillar protein gels with basil seed gum (BSG) at different salt levels and develop the low-salt sausages with BSG. Myofibrillar protein (MP) gels were prepared with or without BSG at different salt concentrations (0.15, 0.30, and 0.45 M). Cooking yield (CY, %), gel strength (GS, gf), viscosity, sulfhydryl contents, protein surface hydrophobicity, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) of MP were measured. Pork sausages were manufactured with 1% BSG at both low-salt (1.0%) and regular-salt (1.5%) levels. pH, color, expressible moisture (EM, %), CY, textural profile analyses, FTIR, sulfhydryl group, and protein surface hydrophobicity (μg) were measured for analyzing the properties of sausages. The addition of 1% BSG to MP gels increased CY and shear stress. Among treatments with different salt concentrations, MP at 0.30 M salt level with 1% BSG had higher GS than that at 0.15 M salt level with BSG. In microstructure, swollen structures were shown in MP gels with BSG. Although CY of sausage at the low-salt concentration (1.0%) decreased, regardless of the BSG addition, hardness values of sausages with regular-salt level increased with the addition of 1% BSG was added. Protein surface hydrophobicity and sulfhydryl contents of sausages increased with the addition of 1% BSG, resulting in higher hardness and lower springiness than those without BSG. These results suggest that BSG could be used as a water-binding and gelling agent in processed meats.

scholarly journals THE CHANGES OF PROTEIN STRUCTURE IN TILAPIA SURIMI DURING GELATION BY RAMAN SPECTROSCOPY

2018 ◽  
Vol 55 (5A) ◽  
pp. 211
Author(s):  
Do Thi Yen
Keyword(s):  
Raman Spectroscopy ◽  
Raman Spectrum ◽  
Protein Structure ◽  
Hydrophobic Interaction ◽  
Structural Changes ◽  
Incubation Temperature ◽  
Textural Properties ◽  
Myofibrillar Protein ◽  
Gel Strength ◽  
Random Coil

Structural changes, textural properties in Tilapia surimi myofibrillar protein during gelation were studied by Raman spectroscopy. The change in the amide I (1600-1700 cm-1) region indicated that the decrease in a-helices content accompanied by increase in ß-sheet and random coil after heating. The conformation of S-S bond was observed in the Raman spectrum near 500-600 cm-1 in the samples of 30-40 oC incubation temperature which produce textural profile with high gel strength. Intensity of the band near 758 cm-1 as well as a slight decrease in I853/I826 ratio when the heat increase 60-70 oC showed that the hydrophobic interaction was involved in the heat-induced gelation of surimi protein. 

Fine Structural Changes in the Microvasculature of the Mouse Pinna: Aging and Radiation Injury

1974 ◽  
Vol 32 ◽  
pp. 54-55
Author(s):  
S. Phyllis Steamer ◽  
Rosemarie L. Devine
Keyword(s):  
Structural Changes ◽  
Radiation Treatment ◽  
Arterial Stenosis ◽  
Ultrastructural Changes ◽  
Vascular Effects ◽  
Microvascular Changes ◽  
Surrounding Connective Tissue ◽  
Fission Neutrons ◽  
Total Body

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.

Evaluation of single-electron movies of glutamine synthetase molecules

1983 ◽  
Vol 41 ◽  
pp. 280-281
Author(s):  
W. Kunath ◽  
E. Zeitler ◽  
M. Kessel
Keyword(s):  
Electron Microscope ◽  
Glutamine Synthetase ◽  
Electron Irradiation ◽  
Structural Damage ◽  
Structural Changes ◽  
Single Electron ◽  
Continuous Series ◽  
Digital Recording ◽  
Recording Device ◽  
Low Exposure

The features of digital recording of a continuous series (movie) of singleelectron TV frames are reported. The technique is used to investigate structural changes in negatively stained glutamine synthetase molecules (GS) during electron irradiation and, as an ultimate goal, to look for the molecules' “undamaged” structure, say, after a 1 e/Å2 dose.The TV frame of fig. la shows an image of 5 glutamine synthetase molecules exposed to 1/150 e/Å2. Every single electron is recorded as a unit signal in a 256 ×256 field. The extremely low exposure of a single TV frame as dictated by the single-electron recording device including the electron microscope requires accumulation of 150 TV frames into one frame (fig. lb) thus achieving a reasonable compromise between the conflicting aspects of exposure time per frame of 3 sec. vs. object drift of less than 1 Å, and exposure per frame of 1 e/Å2 vs. rate of structural damage.

Fine Structural Changes in the Adenohypophyses of Rats Following Destruction of the Pituitary Stalk

1977 ◽  
Vol 35 ◽  
pp. 496-497
Author(s):  
K. Kovacs ◽  
E. Horvath ◽  
J. M. Bilbao ◽  
F. A. Laszlo ◽  
I. Domokos
Keyword(s):  
Structural Changes ◽  
Tissue Injury ◽  
Anterior Lobe ◽  
Uranyl Acetate ◽  
Male Rats ◽  
Pituitary Stalk ◽  
Sequence Of Events ◽  
Pituitary Glands ◽  
Electrolytic Lesions ◽  
Ultrathin Sections

Electrolytic lesions of the pituitary stalk in rats interrupt adenohypophysial blood flow and result in massive infarction of the anterior lobe. In order to obtain a deeper insight into the morphogenesis of tissue injury and to reveal the sequence of events, a fine structural investigation was undertaken on adenohypophyses of rats at various intervals following destruction of the pituitary stalk.The pituitary stalk was destroyed electrolytically, with a Horsley-Clarke apparatus on 27 male rats of the R-Amsterdam strain, weighing 180-200 g. Thirty minutes, 1,2,4,6 and 24 hours after surgery the animals were perfused with a glutaraldehyde-formalin solution. The skulls were then opened and the pituitary glands removed. The anterior lobes were fixed in glutaraldehyde-formalin solution, postfixed in osmium tetroxide and embedded in Durcupan. Ultrathin sections were stained with uranyl acetate and lead citrate and investigated with a Philips 300 electron microscope.

Membrane Changes in Polymorphonuclear Leukocytes During Ionophore (A23187) - Induced Lysosomal Release

1977 ◽  
Vol 35 ◽  
pp. 482-483
Author(s):  
P.L. Moore ◽  
P.L. Sannes ◽  
H.L. Bank ◽  
S.S. Spicer
Keyword(s):  
Structural Changes ◽  
Calcium Release ◽  
Clear Understanding ◽  
Ionophore A23187 ◽  
Enzyme Release ◽  
Extracellular Medium ◽  
Pmn Leukocytes ◽  
Intracellular Ion Concentrations ◽  
Membrane Changes ◽  
Pmn Leukocyte

It is thought that calcium and/or magnesium may play important roles in polymorphonuclear (PMN) leukocyte functions such as chemotaxis, adhesion and phagocytosis. Yet, a clear understanding of the biological roles of these ions has awaited the development of techniques which permit a selective alteration of intracellular ion concentrations. Recently, treatment of cells with the ionophore A23187 has been used to alter intracellular divalent cation concentrations. This ionophore is a lipid soluble antibiotic produced by Streptomyces chartreusensis that complexes with both calcium and magnesium (3) and is believed to carry these ions across biological membranes (4). Biochemical investigations of human PMN leukocytes demonstrate that cells treated with A23187 and extracellular calcium release their lysosomal enzymes into the extracellular medium without rupturing and releasing their soluble cytoplasmic enzymes (5,6). The aim of the present study and and a companion report (7) was to investigate the structural changes that occur in leukocytes during ionophore-induced lysosomal enzyme release.

The Reaction of Brain Structures with OsO4-Zinc-Iodide Stain

1971 ◽  
Vol 29 ◽  
pp. 272-273
Author(s):  
Werner J. Niklowitz
Keyword(s):  
Electron Microscope ◽  
Structural Changes ◽  
Mossy Fiber ◽  
Toxic Metal ◽  
Staining Technique ◽  
Brain Structures ◽  
Oxidase Inhibitor ◽  
Fiber Layer ◽  
Hippocampal Tissue ◽  
Zinc Iodide

After intoxication of rabbits with certain substances such as convulsant agents (3-acetylpyridine), centrally acting drugs (reserpine), or toxic metal compounds (tetraethyl lead) a significant observation by phase microscope is the loss of contrast of the hippocampal mossy fiber layer. It has been suggested that this alteration, as well as changes seen with the electron microscope in the hippocampal mossy fiber boutons, may be related to a loss of neurotransmitters. The purpose of these experiments was to apply the OsO4-zinc-iodide staining technique to the study of these structural changes since it has been suggested that OsO4-zinc-iodide stain reacts with neurotransmitters (acetylcholine, catecholamines).Domestic New Zealand rabbits (2.5 to 3 kg) were used. Hippocampal tissue was removed from normal and experimental animals treated with 3-acetylpyridine (antimetabolite of nicotinamide), reserpine (anti- hypertensive/tranquilizer), or iproniazid (antidepressant/monamine oxidase inhibitor). After fixation in glutaraldehyde hippocampal tissue was treated with OsO4-zinc-iodide stain and further processed for phase and electron microscope studies.

Embedding Procedure for Water Swollen Samples

1970 ◽  
Vol 28 ◽  
pp. 504-505
Author(s):  
Ann M. Thomas ◽  
Virginia Shemeley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ion Exchange ◽  
Structural Changes ◽  
Cross Linking ◽  
Ion Exchange Resins ◽  
Transmission Electron ◽  
First Pass ◽  
Exchange Resins

Those samples which swell rapidly when exposed to water are, at best, difficult to section for transmission electron microscopy. Some materials literally burst out of the embedding block with the first pass by the knife, and even the most rapid cutting cycle produces sections of limited value. Many ion exchange resins swell in water; some undergo irreversible structural changes when dried. We developed our embedding procedure to handle this type of sample, but it should be applicable to many materials that present similar sectioning difficulties.The purpose of our embedding procedure is to build up a cross-linking network throughout the sample, while it is in a water swollen state. Our procedure was suggested to us by the work of Rosenberg, where he mentioned the formation of a tridimensional structure by the polymerization of the GMA biproduct, triglycol dimethacrylate.

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