scholarly journals Comparison of Oxidizing Solutions in the Evaluation of Metmyoglobin Reducing Activity in Dark-Cutting Beef

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
T. Price ◽  
M. Denzer ◽  
G. Mafi ◽  
D. VanOverbeke ◽  
R. Ramanathan

ObjectivesMetmyoglobin reducing activity (MRA) is an inherent muscle biochemical property that can influence color stability. Hence, MRA is used in color research to better understand meat color changes. A greater postmortem muscle pH can affect inherent biochemical properties, including the conventional methodologies to determine MRA. The MRA methodology described in the American Meat Science Association Color Guide utilize changes in nitric oxide induced-metmyoglobin level pre- and post-incubation. However, a greater muscle pH can limit initial metmyoglobin formation. Hence, the methodology discussed in the AMSA color guide may not provide accurate results. Therefore, the objectives of this research were to compare different conditions to induce initial metmyoglobin formation.Materials and MethodsIn the first objective, normal-pH and dark-cutting steaks were dipped in 0.3%s (level recommended in the AMSA color guide) and 1% nitrite solution to induce metmyoglobin formation. Metmyoglobin formed steaks were blotted dry, vacuum packaged, and incubated at 30°C to induce metmyoglobin reduction. In the second experiment, 1% ferricyanide solution was used as an oxidizing agent. The methodology used in objective 1 was used to measure MRA. The experiments were replicated three times and the data were analyzed using the Mixed Procedure of SAS.ResultsThere was no effect (P > 0.05) of nitrite concentration on MRA of dark-cutting beef. However, when 1% ferricyanide was used as an oxidizing agent, initial metmyoglobin was more (P < 0.05) in dark-cutting beef compared with 0.3% sodium nitrite solution.ConclusionThe results suggest that the use of a strong oxidizing agent can impart more metmyoglobin formation in high-pH/dark-cutting beef.

2014 ◽  
Vol 25 (3-4) ◽  
pp. 24-33
Author(s):  
O. I. Dzjuba ◽  
M. V. Yatsenko

The article deals with the history of the study and the current state of research of physiological and biochemical properties of the plant genus Sedum that are useful for human and has been used in folk medicine for many years. It was noticed that antioxidant properties of extracts from plants S. sarmentosum, S. sempervivoides, S. takesimense were caused by the presence of phenolic compounds. Methanol extract of plants S. takesimense exhibited strong scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals as well as significant inhibitory effects on lipid peroxidation and low density lipoprotein (LDL) oxidation induced by a metal ion Cu2+. Various immunomodulatory activities of various fractions of plants extracts (S. dendroideum, S. kamtschaticum, S. sarmentosum, S. telephium) are observed. It was shown that the ethanol extract of S. sarmentosum and it’s fractions suppressed specific antibody and cellular responses to ovalbumin in mice. The methanol extract of plants S. sarmentosum reduced the levels of anti-inflammatory markers, such as volume of exudates, number of polymorphonuclear leukocytes, suppressed nitric oxide synthesis in activated macrophages via suppressed induction of inducible nitric oxide synthase (iNOS). Polysaccharides fractions from plants S. telephium inducing productions of tumor necrosis factor alpha (TNF-α), increasing the intensity of phagocytosis in vitro and in vivo. Methanol extract from the whole part of S. kamtschaticum strongly inhibit PGE2 production from lipopolysaccharide-induced RAW 264.7 cells, a mouse macrophage cell line via modulating activity in gene expression of the enzyme cyclooxygenase-2 (COX-2). The methanol extract of plants S. sarmentosum and the major kaempferol glycosides from S. dendroideum have antinociceptive activity. It was noticed that anti-adipogenic activity of extracts from plants S. kamtschaticum were caused by inhibition of peroxisome-proliferator-activated receptor γ (PPARγ) expression and it’s dependent target genes, such as genes encoding adipocyte protein 2 (аР2), lipoprotein lipase (LPL), adiponectin and CD36. Polysaccharides fractions from S. telephium cause inhibition of cell adhesion of human fibroblast (MRC5) to laminin and fibronectin via interfere with integrin-mediated cell behaviour and they contributed to the role of polysaccharides in cell-matrix interaction. The methanol extract of plants S. sarmentosum exhibited a significant inhibitory activity in the chick embryo chorioallantoic membrane angiogenesis in a dose-dependent manner. The crude alkaloid fraction of S. sarmentosum caused a dose-dependent inhibition of cell proliferation on murine hepatoma cell line BNL CL.2 and human hepatoma cell line HepG2 without necrosis or apoptosis. Alkaloids from plants S. sarmentosum may improve survival of hepatoma patients via the inhibition of excessive growth of tumor cells. Plant’s juices have antiviral activity (S. sarmentosum, S. spurium, S. stahlii). Crude ethanol extract S. praealtum have spermicidal activity of the in mice and a relevant inhibitory effect of aqueous extract on human spermatozoa motility as well as an anti-fertilizing activity in rats. Hepatoprotective triterpenes, e.g., δ-amyrone, 3-epi-δ-amyrin, δ-amyrin and sarmentolin were isolated from S. sarmentosum. 2- and 2,6-substituted piperidine alkaloids (e.g., norsedamine, allosedridine, sedamine, allosedamine) are observed in plants S. acre, which in the presence of data on the use of pyridine and piperidine derivatives for treating neurodegenerative diseases (e.g., Alzheimer's disease), points on the promising research in this area. Taking into account that biologically active compounds are accumulated in the aboveground vegetative organs of plants of Sedum, the prospects of further study of the use of Sedum for the purposes of biotechnology and in the pharmaceutical industry becomes apparent. This work extends the existing views regarding the use of plants Sedum.


Author(s):  
R Patle ◽  
S Dubb ◽  
J Alaghband-Zadeh ◽  
R A Sherwood ◽  
F Tam ◽  
...  

Background Obesity is associated with hypertension, but the exact mechanism is not fully understood. Bariatric surgery significantly decreases weight and blood pressure (BP). Low plasma nitric oxide (NO) and raised asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO, concentrations are associated with both obesity and hypertension. Correlations between the changes in these parameters were studied after bariatric surgery. Methods Weight, BP, plasma ADMA and NO were measured in 29 obese patients (24 female, 5 male) before and six weeks after bariatric surgery. Results Patients were 39.2 ± 1.2 (mean ± SEM) years old and weighed 126 ± 3 kg. Six weeks after the surgery, patients had lost 10 ± 0.7 kg ( P < 0.0001) and mean arterial pressure (MAP) decreased by 11 ± 1.0 mmHg ( P < 0.0001). The plasma ADMA concentration decreased by 24 ± 2% from 5 ± 0.4 to 4.0 ± 0.3 μmol/L ( P < 0.0001). The plasma total nitrite concentration increased by 15 ± 1% from 51.4 ± 2.6 to 60 ± 3 μmol/L ( P < 0.0001). The correlation between the decrease of ADMA and increase of NO subsequent to weight loss was significant ( P < 0.0001). However, MAP was not correlated to the changes in ADMA or NO. Conclusions After bariatric surgery, beneficial changes in BP, NO and ADMA occur, but our findings suggest that these BP changes are independent of changes in the NO–ADMA axis. Other causes for the changes in BP should therefore be considered.


2020 ◽  
Vol 14 (01) ◽  
pp. 085-091
Author(s):  
Sedighe Sadat Hashemikamangar ◽  
Farnoosh Hoseinpour ◽  
Nazanin Kiomarsi ◽  
Mehrzad Gholampour Dehaki ◽  
Mohammad Javad Kharazifard

Abstract Objectives This study aimed to assess the effect of an optical whitening toothpaste on color stability of microhybrid, nanofilled, and microfilled composite resins and resin-modified glass ionomer (RMGI) cement in comparison of two other toothpastes. Materials and Methods In this experimental study, disc-shaped composite samples were fabricated. The samples were then polished using silicon carbide papers. Twenty-seven samples of each material were fabricated and subjected to colorimetry using a spectrophotometer. Each group of material was then divided into three subgroups for the application of conventional whitening and whitening containing blue covarine toothpastes. One operator brushed the samples with an electric soft toothbrush with circular motion twice a day, each time for 30 seconds. Colorimetry was performed at 0, 1, 7, 30, and 90 days. Statistical Analysis Two-way analysis of variance (ANOVA), one-way ANOVA, and Tukey’s honestly significant difference (HSD) test were used for statistical analysis. Results The interaction effect of type of restorative material and time on ∆E was not significant at baseline or 1 day (p > 0.05). The effect of type of toothpaste on ∆E was not significant at baseline or 1 day (p = 0.78) but the effect of type of material was significant (p < 0.05). The toothpastes had significantly different effects on ∆E of Z250 at all time points (p < 0.05) except for ∆E0–30 (p = 0.106). The toothpastes had significantly different effects on ∆E of Z350 and Gradia at all time points (p < 0.05). The same was true for RMGI except for ∆E0–7 (p = 0.43) and ∆E0–90 (p = 0.52). The majority of color changes caused by toothpastes were not clinically perceivable (∆E < 3.3), except for ∆E0–90 by the whitening toothpaste (∆E = 9), ∆E0–90 by the conventional toothpaste for Z350 (∆E = 3.9), and ∆E0–1 by the whitening toothpaste for RMGI (∆E = 3.7). Conclusion The color change of all composite samples was not clinically perceivable (<3.3) at all time points, which shows that the tested toothpastes do not cause a significant change in color of composite materials.


2019 ◽  
Vol 9 (4) ◽  
pp. 27-32
Author(s):  
Olga A. BALANDINA ◽  
Svetlana M. PURING

The analysis of the values of the concentrations of the formed nitrogen oxides and the temperatures of the jet plume under various conditions of mixture formation is carried out. The plots of the distribution of torch temperatures and concentrations of nitric oxide in the calculated area for oxidizer temperatures of 20, 60, 100, 150, and 200 ° C were obtained and analyzed. Mathematical modeling of the gaseous fuel combustion process was carried out using the FlowVision software package. An analysis of the results showed that a decrease in the temperature of the air supplied as an oxidizing agent leads to a significant decrease in the concentration of nitrogen oxides in flue gases, while not significantly affecting the change in the flame temperature. The research results can be used to solve the problems of optimizing boiler plants, in order to reduce harmful flue gas emissions. Further modeling is planned to determine the dependence of the influence of various factors on the degree of formation of nitrogen oxides in the flue gases of boiler plants.


2019 ◽  
Vol 3 (2) ◽  
Author(s):  
J. V. Cooper ◽  
S. Suman ◽  
Z. D. Callahan ◽  
K. C. Kerns ◽  
M. Zigo ◽  
...  

ObjectivesPrevious research revealed a relationship between meat color and beef tenderness and indicated that myoglobin can inhibit calpain-1 in solution. The objective of this study was to determine the extent to which myoglobin and beef color are associated with calpain activity and beef tenderness.Materials and MethodsBeef Longissimus dorsi samples from the left side of Holstein beef carcasses (n = 21) were collected immediately post exsanguination on the processing floor for 0 h analyses. Muscle temperature and pH was measured at 0, 24, and 48 h postmortem. After USDA quality and yield grade determination, steaks (n = 6) were removed from the right side of each carcass (n = 21) at 48 h for analyses at 48 and 336 h postmortem. Color (L*, a*, and b* values), surface myoglobin redox forms, metmyoglobin reducing activity (MRA), total myoglobin concentrations, slice shear force (SSF), Warner-Bratzler shear force (WBSF) were measured. Calpain-1 concentrations and autolysis were determined via Western blot at 0, 48, and 336 h.ResultsDecline in muscle pH was 6.4, 5.8, and 5.6 at 0, 24, and 48 h, respectively. Shear force values at 48 h were 73.19 N for WBSF and 384.21 N for SSF and at 336 h were 48.75 N for WBSF and 260.47 N for SSF. Myoglobin reducing activity at 336 h was positively correlated to WBSF at 48 h and negatively correlated to calpain-1 concentration at 0 h (P < 0.05; Table 9). Color measurements of L* and b* at 48 h were moderately correlated with WBSF at 336 h (P < 0.05; Table 9). The b* measurement at 336 h showed a moderate relationship to calpain-1 concentration at 0 h (P < 0.05; Table 9).ConclusionModerate correlations between color and tenderness measurements taken at 48 h with those taken at 336 h were discovered indicating that myoglobin may impact calpain-1 in vivo.Table 9Correlations (P-values) between selected color and tenderness measurements (n = 21)


2018 ◽  
Vol 5 (4) ◽  
pp. 76
Author(s):  
Mone Laiz Bortoli ◽  
Cristina Von Appen ◽  
Camila Longoni ◽  
Carmen Beatriz Borges Fortes ◽  
Jefferson Tomio Sanada

Aim: This work aimed to evaluate the color stability of an acrylic resin chemically activated (ARCA) using different handling techniques, and a bisacrylic resin when exposed to different pigmentation solutions.Material and Methods: Silicon matrixes were confectioned (10x10x3mm) to be used as specimens. The groups were designed as follows: Group Pot, Group Brush, Group Manufacturer and Group Bisacrylic (n=18). Each group was exposed to three different pigmentation solutions: distilled water, coke and chlorhexidine digluconate 0.12%. Three readings were performed for each specimen using a spectrophotometer, and the evaluations were carried out in three different time. After the color reading, three averages and the standard deviation of variation were performed after 24 hours (T1), 7 days (T2) and 14 days (T3). Data were submitted to the ANOVA and 2 criteria and Tukey (P<0.05) in the statistical software SSPS 18 for Macintosh (SPSS Inc., Chicago, USA).Results: When compared the solutions in each group of material, there was no statistically significant difference, except for T3, where the group Dencor Brush and Bisacrylic demonstrated higher color variation in all the solutions, even in the control group, and the values in Chlorhexidine higher than the other, showing greater instability after 14 days.Conclusions: With the results, bisacrylic resin used as provisory prosthesis material presents greater color instability than the ARCA, when submitted to different solutions. Bisacrylic resin and Dencor Brush present significantly visible color changes in chlorhexidine solution after 14 days. All the materials in coke solution present homogeneity in the color change after 7 days exposition to the solution, with no visible color change.


2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 81-85
Author(s):  
Firdevs Kahvecioğlu ◽  
Elçim Çoban ◽  
Hayriye Esra Ülker

Aim: The aim of this study is to evaluate the effects of whitening toothpaste applications on the color stability of different tooth-colored restorative materials (Fuji IX, GC Fuji II LC, Equia Forte, and Kerr Point 4)  Methodology: Standardized fourty disc-shaped specimens were prepared from esthetic restorative materials and polished. The baseline color values of each specimen were then measured using a spectrophotometer, according to the Commission Internationale de l'Eclairage L*, a*, and b* (CIELAB) color scale. Ten specimens from each group were then immersed in two different beverages (cherry juice and coke) for seven days. After immersion, the color value of each specimen was re-measured. Each sample was brushed with whitening toothpaste for 30 seconds using an electric toothbrush. The samples were kept in distilled water at room temperature and brushing continued twice a day for seven days. The color change value, Delta E (ΔE), was calculated. Data were analyzed by two-way ANOVA and post hoc Tukey's test. Results: When the results were evaluated, after the colored samples had been brushed with whitening toothpaste, a difference was found between the Delta E values according to the materials used (p<0.001), but no difference was found in relation to the beverages (p>0.001). When the values of the color changes were evaluated after the first brushing with whitening toothpaste and before the specimens were colored with drinks, a difference was observed in the Fuji II cola, Fuji II cherry, and Equia Forte cola groups (p<0.05). When the values of the color changes were evaluated for specimens in which brushing had been done twice a day for seven days with whitening toothpaste and before they were colored with drinks, a significant difference was observed in the Fuji II cherry and Equia Forte cola groups (p<0.05). Conclusion: Using Signal White Now whitening toothpaste for 2 min 2 times a day for seven days caused significant changes in the color of the restorative materials. The color change is dependent upon the type of restorative material that is used.   How to cite this article: Kahvecioğlu F, Çoban E, Ülker HE. The effect of optical brightening toothpaste on the color stability of esthetic restorative materials. Int Dent Res 2021;11(Suppl.1):80-4. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.13   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Bryant Anthony Irawan ◽  
Stacey Natalie Irawan ◽  
Sam’an Malik Masudi ◽  
Ninin Sukminingrum ◽  
Mohammad Khursheed Alam

This study aims to evaluate the effects of vital tooth bleaching with carbamide peroxide home bleaching and in-office bleaching on the color stability and 3D surface profile of dental restorative filling materials. Thirty discs (n=30) measure 6 mm in diameter and 2 mm thick for each of three restorative materials. These are nanofilled composite Filtek Z350 XT, the submicron composite EsteliteΣQuick, and nanofilled glass ionomer Ketac N100 nanoionomer and were fabricated in shade A2. Each group was further divided into three subgroups (n=10): subgroup A (Opalescence PF), subgroup B (Opalescence Boost in-office bleaching), and subgroup C (distilled water) serving as control. Samples were bleached according to the manufacturer’s instructions for a period of two weeks. The Commission Internationale de L’Eclairage (CIEL*,a*,b*) system was chosen for image processing, while 3D surface profile was tested with atomic force microscopy (AFM). Statistical analyses were performed with the Mann-Whitney tests and Krusal-Wallis with aPvalue of ≤0.05. The three restorative materials showed significant color changes (ΔE);P≤0.05. In diminishing order, the mean color changes recorded were EsteliteΣ(3.82 ± 1.6) > Ketac Nano (2.97 ± 1.2) > Filtek Z350 XT (2.25 ± 1.0). However, none of the tested materials showed statistically significant changes in surface roughness;P>0.05.


2019 ◽  
Vol 30 (1) ◽  
pp. 52-57 ◽  
Author(s):  
Eduardo Haruki Ozera ◽  
Fernanda Miori Pascon ◽  
Américo Bortolazzo Correr ◽  
Regina Maria Puppin-Rontani ◽  
Aline Rogéria de Castilho ◽  
...  

Abstract This study evaluated gloss and color changes of esthetic restorative materials subjected to different acidic beverages. Specimens of resin composites (Z350XT (Z350), IPS Empress Direct (ED), Charisma Diamond (CD)) were prepared and the initial surface gloss and color (ΔE) were measured (n=10). Then, the specimens were immersed in 4 mL of each of the different beverages (cranberry juice; Coca-Cola; coffee or artificial saliva) during 15 min, 3x/day for 14 days and new gloss and color readings were obtained. Color change was evaluated with the ΔE formula and gloss change values were obtained by the formula: (final gloss - initial gloss). Data was submitted to two-way ANOVA followed by Tukey’s post hoc test (a=0.05). CD showed the lowest color change among resin composites. The highest ΔE values were obtained after immersion in coffee and cranberry juice. Coffee promoted the highest gloss change (worst gloss retention), followed by cranberry juice, Coca-cola and artificial saliva (p<0.05). The type of beverage significantly influenced the gloss of resin composites. Coca-cola reduced gloss of the three resin composites in a similar manner. Coffee affected the ED gloss more than that of Z350 and CD, while cranberry juice affected Z350 more than ED and CD. Saliva had a more pronounced effect on the gloss retention of CD than ED. The beverages used in this study influenced the optical surface properties of the composites studied.


2013 ◽  
Vol 42 (4) ◽  
pp. 237-242 ◽  
Author(s):  
Ana Carolina Pero ◽  
Jaqueline Ignárcio ◽  
Gabriela Giro ◽  
Danny Omar Mendoza-Marin ◽  
André Gustavo Paleari ◽  
...  

INTRODUCTION: The occurrence of stomatitis is common since the surface characteristics of the dentures may act as reservoirs for microorganisms and have the potential to support biofilm formation. PURPOSE: To assess the surface properties (wettability/roughness) and color stability of an acrylic resin combined with the antimicrobial polymer poly (2-tert-butylaminoethyl) methacrylate (PTBAEMA). MATERIAL AND METHOD: Thirty disc-shaped specimens of an acrylic resin (Lucitone 550) were divided into three groups: 0% (control); 5% and 10% PTBAEMA. Surface roughness values (Ra) were measured using a profilometer and wettability was determined through contact angle measurements using a goniometer and deionized water as a test liquid. Color data were measured with a spectrophotometer. Kruskal-Wallis and Dunn's test were used to compare roughness values. Wettability data were analyzed using ANOVA and Tukey's test. Color data were compared using the Student's t-test and ∆E values were classified according to the National Bureau of Standards (NBS). All statistical analyses were performed considering α=.05. RESULT: Significant differences (p<.05) were detected among the groups for roughness, wettability and color stability. According to the NBS, the color changes obtained in the 5% and 10% PTBAEMA groups were "appreciable" and "much appreciable", respectively. CONCLUSION: It could be concluded that PTBAEMA incorporation in an acrylic resin increased the roughness and wettability of surfaces and produced color changes with clinical relevance.


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