Effect of PH-Shifting Treatment on the Biochemical and Thermal Properties of Myofibril Protein

2011 ◽  
Vol 236-238 ◽  
pp. 2231-2235 ◽  
Author(s):  
Xiang Jin Fu ◽  
Qin Lu Lin ◽  
Zhong Hai Li ◽  
Shi Ying Xu ◽  
Jin Moon Kim
Keyword(s):  
Differential Scanning Calorimetry ◽  
Acid Treatment ◽  
Alkali Treatment ◽  
Surface Hydrophobicity ◽  
Scanning Calorimetry ◽  
Sds Page ◽  
High Turbidity ◽  
Endothermic Transition ◽  
Ph Shifting ◽  
Myofibril Protein

The pH-shifting treatment (including acid treatment and alkali treatment) caused partly denaturation and degrading of myofibril. The pH-shifting treatment increased the surface hydrophobicity, surface -SH content and total -SH content, reduced the Ca-ATPase activity. Acid treated myofibril (ACM) did not show any endothermic transition peak in differential scanning calorimetry (DSC); while alkali treated myofibril (AKM) showed reduced T max value for myosin and actin. The SDS-PAGE indicated that acid treatment caused severe degrading of myosin heavy chain. High turbidity of ACM indicated more myofibril aggregated during acid treatment. The final G’ was in the decline order of M (550 Pa), AKM (135 Pa), and ACM (25 Pa). In conclusion, the alkali treatment was milder than the acid treatment.

Seed protein content and composition of near-isogenic and induced mutant pea lines

1993 ◽  
Vol 3 (3) ◽  
pp. 187-194 ◽  
Author(s):  
M. D. Perez ◽  
S. J. Chambers ◽  
J. R. Bacon ◽  
N. Lambert ◽  
C. L. Hedley ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Protein Content ◽  
Total Protein ◽  
Dry Weight ◽  
Total Protein Content ◽  
Scanning Calorimetry ◽  
Sds Page ◽  
A Chain ◽  
Total Seed ◽  
Mutant Pea

AbstractTotal protein content and amounts of albumin, legumin and vicilin have been determined for pea seeds from lines near-isogenic except for genes at the rugosus loci, r and rb (RR/RbRb; rr/RbRb; RR/rbrb; rr/rbrb). Seeds with the wildtype, round-seeded phenotype (RR/RbRb) had less protein on a total seed dry-weight basis than any of the wrinkled-seeded lines and this protein had a lower proportion of albumin. The lines which had recessive alleles at both r and rb loci had the highest proportion of protein and the highest proportion of albumin. The roundseeded peas possessed nearly two-fold more legumin than the double recessive line, with proportions for the two single recessive lines falling in between these extremes. Vicilin levels were similarfor all four near-isogenic lines. SDS-PAGE analysis of the isolated albumin, legumin and vicilin fractions revealed no significant differences between the four lines. Differential scanning calorimetry of protein extracts showed that all the wrinkled-seeded near-isolines possessed legumin fractions with diminished thermal stability relative to that from the roundseeded, wild-type line.Chemically-induced mutants were also analysed for protein content and composition. These mutants have previously been shown to display great variation in starch and lipid levels. Total protein varied from 20.3% to 37.9%; however, relative proportions of albumin, legumin and vicilin were similar in all mutant lines. SDS-PAGE analysis identified two mutant pea lines which possessed a legumin A-chain of 65 000 Mr as well as the typical 45 000 Mr form. Differential scanning calorimetry of protein extracts indicated that the legumin in all mutants had lower enthalpies of denaturation than the legumin in the round-seeded parent.The mutant pea lines possess exceptional variation with respect to starch, lipid and protein which raises opportunities for their use in the food and animal feedstuff industries.

Crystalinity Properties of Carbon Nanotube-Polyvinylidene Fluoride Composites

2008 ◽  
Vol 1134 ◽  
Author(s):  
Xiaobing Shan ◽  
Pei-xuan Wu ◽  
Lin Zhang ◽  
Zhong-Yang Cheng
Keyword(s):  
Differential Scanning Calorimetry ◽  
Carbon Nanotube ◽  
Acid Treatment ◽  
Polyvinylidene Fluoride ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Β Phase ◽  
Solution Cast ◽  
Solution Cast Method

AbstractSingle-wall and multi-wall carbon nanotube blends (0 to 0.5 vol% ) with polyvinylidene fluoride (PVDF) have been prepared using solution cast method and characterized. By acid treatment, it has been observed that nanotube has been well functionalized and uniformly dispersed into the polymer. X-ray diffraction analysis coupled with differential scanning calorimetry (DSC) has revealed that carbon nanotube alters the crystallinity of PVDF and thereby enhances the β-phase in PVDF. Experimental results have demonstrated that enhancement of β-phase is a function of carbon nanotube concentration.

scholarly journals Staling of sponge cakes with added emulsifiers

2020 ◽  
Author(s):  
Maria Marudova ◽  
Stanko Stankov ◽  
Marianna Baeva
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Differential Thermal Analysis ◽  
Control Sample ◽  
Bound Water ◽  
Storage Period ◽  
Scanning Calorimetry ◽  
Retarding Effect ◽  
Starch Retrogradation ◽  
Endothermic Transition

AbstractThe effect of three types of emulsifiers (polyglycerol monostearate ester – E475, sucrose stearate ester – E473 and modified inulin palmitate ester – HP-25) on the starch retrogradation in sponge cake (SC) during storage was investigated. The method of differential scanning calorimetry (DSC) was applied to determine the changes in the starch retrogradation during the staling process. The retrogradation temperature and the enthalpy of the endothermic transition decreased when emulsifiers were added. The lowest values of the enthalpy for the whole storage period were found for SC with 1% HP-25. The methods of differential thermal analysis (DTA) and thermogravimetry analysis (TGA) showed significantly bigger (1.43 times) amount of strongly bound water in the crumb of the SC with E475 and HP-25 in comparison to the control sample on the sixth day of storage. Based on our results, emulsifiers possessed retarding effect on the starch retrogradation and extend the shelf-life of the SC.

scholarly journals Thermal behavior of corn starch granules modified by acid treatment at 30 and 50°C

2008 ◽  
Vol 33 (3) ◽  
pp. 13-18 ◽  
Author(s):  
C. Beninca ◽  
I. M. Demiate ◽  
L. G. Lacerda ◽  
M. A. S. Carvalho Filho ◽  
M. Ionashiro ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Optical Microscopy ◽  
Acid Treatment ◽  
Corn Starch ◽  
Starch Granules ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Thermoanalytical Techniques ◽  
Physical Chemical

Unprocessed native starches are structurally too weak and functionally too restricted for application in today's advanced food technologies. Processing is necessary to engender a range of functionality. Naturals or natives starches can be modified by using several methods physical, chemical, enzymatic or combined, according industrial purposes. In this work, native corn starch was hydrolyzed by hydrochloric acid solution and investigated by using thermoanalytical techniques (thermogravimetry - TG, differential thermal analysis - DTA and differential scanning calorimetry - DSC), as well as optical microscopy and X-ray diffractometry. After acid treatment at 30 and 50°C, a decrease of gelatinization enthalpy (ΔHgel) was verified. Optical microscopy and X-ray diffractometry allowed us to verify the granules contorn and rugosity typical of cereal starches.

Thermal Stability of N-Heterocycle-Stabilized Iodanes – A Systematic Investigation

2019 ◽  
Author(s):  
Andreas Boelke ◽  
Yulia A. Vlasenko ◽  
Mekhman S. Yusubov ◽  
Boris Nachtsheim ◽  
Pavel Postnikov
Keyword(s):  
Thermal Stability ◽  
Differential Scanning Calorimetry ◽  
Thermogravimetric Analysis ◽  
Systematic Investigation ◽  
Scanning Calorimetry ◽  
Thermal Stability Of

<p>The thermal stability of pseudocyclic and cyclic <i>N</i>-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-l<sup>3</sup>-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. NHIs bearing <i>N</i>-heterocycles with a high N/C-ratio such as triazoles show among the lowest descomposition temperatures and the highest decomposition energies. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation. </p>

Optimasi Proses Pembuatan dan Karakterisasi Fisik Niosom Sinkonin

2019 ◽  
Vol 16 (2) ◽  
pp. 178
Author(s):  
Hariyanti Hariyanti ◽  
Sophi Damayanti ◽  
Sasanti Tarini
Keyword(s):  
Differential Scanning Calorimetry ◽  
Particle Size ◽  
Hair Follicle ◽  
Scanning Calorimetry ◽  
Span 60

Sinkonin praktis tidak larut dalam air, sedikit larut dalam kloroform dan alkohol. Hal ini berdampak pada rendahnya penetrasi transfollicular sinkonin, karena hanya bahan aktif hidrofilik yang mampu melewati hair follicle. Dengan demikian dibutuhkan satu sistem penghantaran yang mampu menurunkan hidrofobisitas sinkonin untuk meningkatkan penetrasi sinkonin ke follicle. Niosom merupakan vesikel ampifilik dengan struktur lapisan rangkap yang terbentuk dari hidrasi kombinasi surfaktan nonionik dan kolesterol yang mampu menurunkan hidrofobisitas sinkonin. Penelitian ini bertujuan untuk menentukan proses pembuatan niosom sinkonin yang optimum. Pembuatan niosom sinkonin diawali dengan menentukan temperatur gelasi (Tg) dari span 60 dengan Differential Scanning Calorimetry (DSC), kemudian dilanjutkan dengan optimasi proses meliputi: optimasi kecepatan rotavapor pembentukan film lapis tipis, temperatur hidrasi, kecepatan rotavapor hidrasi, waktu hidrasi, dan waktu sonikasi. Karakteristik vesikel niosom yang optimal meliputi: ukuran partikel dan indeks polidispersitas dengan menggunakan Particle Size Analized (PSA) serta efisiensi penjeratan sinkonin dengan menggunakan KCKT. Temperatur gelasi (Tg) span 60 45±2 oC, kecepatan rotavapor pembentukan film lapis tipis niosom 210 rpm, temperatur hidrasi 55±2 oC, kecepatan rotavapor hidrasi 210 rpm, waktu hidrasi 20 menit, waktu sonikasi suspensi niosom 1 menit. Ukuran vesikel yang diperoleh adalah 100–200 nm, indeks polidispersitas 0,2–0,4 dan efisiensi penjeratan niosom sinkonin 84,49±0,0025%. Proses pembuatan niosom sinkonin memiliki pengaruh besar terhadap hasil ukuran vesikel dan efisiensi penjeratan niosom sinkonin.

Improving Wire Sweep Performance by Measuring Degree of Cure of Epoxy Mold Compounds

2011 ◽  
Author(s):  
Sheila Liza B. Dal
Keyword(s):  
Differential Scanning Calorimetry ◽  
Shelf Life ◽  
Trial And Error ◽  
Active Components ◽  
Scanning Calorimetry ◽  
Degree Of Cure ◽  
Electronic Package ◽  
Viscosity Changes ◽  
Epoxy Mold Compounds

Abstract The choice of epoxy mold compound (EMC) for an electronic package is based mostly on how much protection it provides to the active components in the package. But the choice is not a straightforward process. Rather it is mostly trial and error using different assembly parameters to find the most robust material while assembly defects are monitored. One such defect associated to EMC processing is wire sweep, and many studies have shown that it is mainly caused by viscosity changes in the EMC. In this study, samples of EMC in various stages of shelf life and staging times were analyzed for degree of cure using a method called differential scanning calorimetry (DSC). Samples are then processed at assembly for wire sweep measurement. It was found out that degree of cure increases with staging time at different rates for each shelf life. It was also found out that wire sweep did not only increase with degree of cure but it was also found to be predictable with respect to the latter. Using this information, the age and staging limit for each material was identified that would not cause wire sweep issues.

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