Influencing Factors and Variation Trends of Muscle pH in Chickens after Slaughter

[Objective] This study aimed to investigate influencing factors and variation trends of muscle p H in chickens after slaughter. [Method] Beijing You chickens and Lohmann brown chickens were reared under the same conditions and slaughtered at the age of 8, 16 and 20 weeks, respectively. At different time（15 min, 1, 4, 8,12, 24 and 48 h） after slaughter, p H value of breast muscles and leg muscles was measured. [Result] The results showed that muscle position, post-slaughter time,gender and week age were important factors influencing p H value, but the breed had little effect. Within 1 h after slaughter, p H value of breast muscles and leg muscles declined rapidly, which reached the minimum level at 12 h after slaughter,and then increased slowly. In addition, p H value of leg muscles exhibited higher decline and increase rates than that of breast muscles to some extent. [Conclusion]This study provided basis for breeding of chickens with excellent meat quality.

Eco-Friendly pH Indicator Based on Natural Anthocyanins from Lycium ruthenicum

An eco-friendly and visual pH indicator was developed based on cotton fabrics dyed with natural Lycium ruthenicum extract(LRE),whose color changed from red to purple,blue and green at pH of 2-10.Three methods for dyeing cotton fabrics with LRE were attempted,namely pre-mordanting,simultaneous mordanting,and post-mordanting methods with different dyeing temperatures,dyeing times and dyebath pH values.The cotton fabrics exhibited the highest K/S value when they were dyed under a dyebath of pH 6 at 20℃for 90 min in the case of the simultaneous mordanting method.Meanwhile,the dyed cotton fabrics also showed reversible pH-dependent color changes.The developed flexible pH indicator based on renewable natural materials is suitable for multiple applications in environmental monitoring and smart textiles.

Rapid Estimation of Enantioselectivity in Lipase-catalyzed Resolution of Glycidyl Butyrate Using pH Indicator

A simple method for rapid estimation of the enantioselectivity of lipase in resolution of chiral esters is described. The enantioselectivity of lipase can be estimated rapidly through comparing the difference of hydrolysis rates for the racemic ester and its slow reacting enantiomer under the same condition because the difference mainly depends on the enantioselective ratio（E values）. The higher the enantioselectivity of enzyme, the larger the difference of hydrolysis rate. The bromothymol blue（BTB） can be used as pH indicator for microplate reader to monitor the formation of acid in lipase-catalyzed hydrolysis of esters. This method has been successfully used to rapidly estimate the enantioselectivity of several lipases in the resolution of glycidyl butyrate.

A Visual pH Indicator through Purple Cabbage Dye for Freshness Test of Venison

A visual pH indicator through purple cabbage dye is selected to test the freshness of venison.Chitosan and cassava starch of an equal weight were used to prepare the film-forming matrix of the indicator.The crystallization of natural purple cabbage dyes with a weight ratio of 5%,10%,20%and 40%were added to the matrix,respectively.The pH color test showed that the natural purple cabbage lyophilized powder with a weight ratio of 40%was the best for the pH indicator,which was used to test the freshness of venison stored at 4℃.The total bacterial count,volatile basic nitrogen(TVB-N)and thiobarbituric acid(TBA)of venison were tested through an experiment.When stored at under 4℃,a significant color change of the indicator from pink to blue-green was shown when the total amount of volatile basic nitrogen(TVB-N)(22.78 mg/100 g)exceeded the critical value(20 mg/100 g).The test result showed that the indicator was very sensitive to pH value and it would help customers identify the freshness of venison.

Temporal and Spatial Change of Soil Organic Matter and pH in Cultivated Land of the Songliao Plain in Northeast China during the Past 35 Years

Soil organic matter(SOM)and pH are not only an important part of soil fertility,but also a source of nutrients for plants and an energy source for the life activities of soil microorganisms(Huang,2000).Moreover,soil organic matter(SOM)has a great impact on soil properties and can improve soil fertility and buffering performance.

Roles of interstitial fluid pH in diabetes mellitus: Glycolysis and mitochondrial function

The pH of body fluids is one the most important keyfactors regulating various cell function such as enzyme activity and protein-protein interaction via modification of its binding affinity. Therefore, to keep cell function normal, the pH of body fluids is maintained constant by various systems. Insulin resistance is one of the most important, serious factors making the body condition worse in diabetes mellitus. I have recently found that the pH of body(interstitial) fluids is lower in diabetes mellitus than that in non-diabetic control, and that the lowered pH is one of the causes producing insulin resistance. In this review article, I introduce importance of body(interstitial) fluid pH in regulation of body function, evidence on abnormal regulation of body fluid pH in diabetes mellitus, and relationship between the body fluid pH and insulin resistance. Further, this review proposes perspective therapies on the basis of regulation of body fluid pH including propolis(honeybee product) diet.

pH influences the profiles of midgut extracts in Cnaphalocrocis medinalis(Guenée) and its degradation of activated Cry toxins

Midgut extracts play crucial roles in food digestion and detoxification.We evaluated the effect of pH on the profiles of the midgut extracts in rice leaffolder,Cnaphalocrocis medinalis and the degradation of activated Bt-toxins by the midgut extracts under different pH conditions.Total protease activity increased slightly with the increase with the simulated pH in the midgut extracts and the maximal protease activity was observed at pH 10.5,while an upward trend was observed as the pH of reaction buffer increased.Activity of chymotrypsin-like enzymes increased with pH,both in the buffer and midgut extracts,while the activity of trypsin-like enzyme was unaffected.Degradation of the activated Cry2 A by the midgut extracts enhanced as the pH increased.Cry2 A was fully degraded into smaller segments at pH 9.0-10.5.Activated Cry1 C protein at pH 9.0-10.5 was partially degraded by the midgut extracts.Activated Cry1 Aa and Cry1 Ac were partially degraded into fragments by the midgut extracts at high pH.These results will facilitate our further understanding of the interactions between C.medinalis and the Cry toxin.

Caecal pH is a biomarker of excessive colonic fermentation

AIM: To ascertain whether caecal pH is different in patients with irritable bowel syndrome (IBS), whose primary symptoms are bloating and distension, to healthy controls.

Early effects of Lansoprazole orally disintegrating tablets on intragastric pH in CYP2C19 extensive metabolizers

AIM: To compare rabeprazole (RPZ; 10 mg) with Lansoprazole orally disintegrating tablets (LPZ; 30 mg OD) in terms of antisecretory activity and blood drug concentration after a single dose. METHODS: Eight H pylori-negative cytochrome P450 (CYP) 2C19 extensive metabolizers were assigned to receive a single oral dose of RPZ 10 mg or LPZ 30 mg OD. Twelve hour intragastric pH monitoring was perform- ed on the day of treatment. Blood samples were also collected after the administration of each drug. RESULTS: LPZ 30 mg OD induced a significantly earlier rise in blood drug concentration than RPZ 10 mg; consequently, LPZ 30 mg OD induced a significantly earlier rise in median pH in the third and fourth hours of the study. CONCLUSION: In H pylori-negative CYP2C19 extensive metabolizers, LPZ 30 mg OD induced a significantly faster inhibition of gastric acid secretion than RPZ 10 mg.

Modeling and Control of pH in Pulp and Paper Wastewater Treatment Process

Pulp and paper industry is responsible for large discharge of highly polluted effluents, which often be treated by biological treatment process. For biological treatment system, pH is an important environmental factor that can influence the activity of microorganisms. In general, the optimal pH for aerobic processes is around neutral pH (7_7.8) and for the anaerobic process is between 6.8_7.2. The control of pH is a difficult link in the biological treatment system due to its nonlinearity and large time-delay. Aiming at the difficult point in the pH control of the biological wastewater treatment system, a mathematical model of pH control is estab-lished in the essay. On this basis, a traditional PID control and a cascade control are adopted to carry out simulation and comparison with MATLAB. The results show that the cascade control has better comprehen-sive effect in terms of response speed, stability and disturbance resistance.

Variation Laws and Influencing Factors of pH in Fishery Waters in Quzhou City

[Objectives] This study was conducted to strengthen the understanding of the variation laws of pH in fishery waters. [Methods]Based on the investigation data of pH, dissolved oxygen(Do), water temperature(T) and chlorophyll a(Chl. a) of the fishery waters in Quzhou City from 2017 to 2020, the seasonal variation characteristics and influencing factors of pH in the fishery waters were analyzed and discussed. [Results] The pH of the fishery waters in Quzhou City was in the range of 6.40-11.3, and was characterized by the highest seasonal variation in spring and the lowest in winter. The correlation analysis showed that water temperature and pH were significantly positively correlated in spring and summer(P<0.05), and the photosynthesis of phytoplankton was the main reason that affected the pH of water bodies in spring and summer. There was a negative correlation between water temperature and pH in winter, and the pH in the natural waters had a significant negative correlation with water temperature(P<0.05). The balance of carbonate system in the water bodies was the main reason that affected the pH of water in winter. The level of water eutrophication(Chl. a) affected the pH of fishery waters to a certain extent. When Chl. a<10 μg/L, there was a significant positive correlation between the pH of fishery waters and Chl. a(P<0.05). Various environmental factors had different effects on the pH of different types of fishery waters. The stepwise regression analysis showed that the pH of natural waters was mainly affected by Chl. a, and the pH of aquaculture waters was mainly affected by water temperature and dissolved oxygen. [Conclusions]This study provides certain theoretical support for actual production management.

Analysis on the Change of Soil pH in Tobacco Fields During the Cultivation of Flue-cured Tobacco

[Objectives] This study was conducted to understand soil p H changes during tobacco planting and its reasons. [Methods]Soil samples were collected from Jingdong,Jinggu and Zhenyuan tobacco-planting areas of Pu'er City before tobacco planting and during different growth stages of tobacco. [Results] Planting flue-cured tobacco changed the soil p H value. First,it was affected by the nicotine produced by the root system of tobacco plants. Second,it was affected by the type of soil. [Conclusions] This study has certain theoretical guiding significance for the cultivation management of flue-cured tobacco and the arrangement of ensuing crops.

VARIATION OF PH IN ATMOSPHERIC PRECIPITATION IN CITIES OF JILIN PROVINCE

Through statistical analysis on data of atmospheric precipitation samples of 8 cities from 1992 to 1997,this paper discussed temporal and spatial variations of pH in atmospheric precipitation in Jilin Province, China Monitored pH value in the 8 representative cities was converted into hydrogen ion consistency and average condsistency was calculated by weighting precipitation, then mean pH value was calculated according to average hydrogen ion consisteney. Results show that atmospheric precipitaion of cities in Jilin Province is basically. neutral, but in Tumem and Hunchun cities atmospheric precipitation is seriously acid. The average pH value of atmospheric precipitation of the eastern cities of Tumen and Hunchun in many years is 5. 12 and 5. 38 respectively, and the atmospheric precipiboon acidity in the two cities is quite serious with the extreme low pH is 3. 91 and 4. 28 respectively. Most of the acid precipitation occurred in summer and autumn seasons in the 8 monitored cities, so that the low pH value of atmoopheric pmeipitation occurred in summer and autunm seasons and high pH value occurred in winter ed spring seasons. The temporal and spatial variations of pH in atmospheric precipitation in Jilin Province are attributed to both local sources and peripheral sources, and are related to both natural and artificial factors.

Blood pH in coronary artery microthrombosis of rats

Objective:To study the mechanism and significance of pH change in the coronary artery microthrombosis of rats.Methods:After the sodium laurate-induced model of coronary artery microthrombosis of rats was constructed,the vascular endothelial cells were separated and then cultured in the mediums with different pH values for 24 h.Enzyme linked immunosorbent assay was used to detect the content of von Willebrand factor(vWF) in the medium;while the real-time PCR and western blot assay were used to detect the expression of fibrinogenlike protein 2(FGL2) at the mRNA and protein level.The comprehensive evaluation was performed to discuss the effect of pH change on the coronary artery microthrombosis of rats.Results:The expression level of vWF detected by enzyme linked immunosorbent assay was 336.67±24.95,311.33±14.98,359.67±39.63,354.67±49.01 and 332.00±33.42(pg/mL) respectively;while the expression of vWF in the model group was 570.00±57.94,524.67±57.94,437.00±95.38,415.33±44.38 and 444.67±74.31 respectively.Being cultured under the different pH values,the relative expression level of FGL2 mRNA in the model group was 7.93±0.93,6.70±0.70.5.03±0.32,5.13±0:40 and 5.57±0.83 respectively.Conclusions:The coronary artery microthrombosis of rats can cause the high expression and secretion of vWF.Meanwhile,FGL2 is also up-regulated in the thrombosis and such up-regulation is more significant in the condition with low pH,which indicates that the low-pH condition may be one of factors that contribute to the cardiovascular diseases.

Roles of pH in the NH_(4)^(+)-induced corrosion of AZ31 magnesium alloy in chloride environment

Corrosion behavior of AZ31 magnesium alloy in NH_(4)^(+)-bearing chloride solution with controlled pH was investigated by weight loss experiment, hydrogen collection, and electrochemical test combined with surface morphology and topography observation. The results show that NH_(4)^(+) and pH of the solution can affect the corrosion of AZ31 magnesium alloy. The existence of NH4+affects the formation and dissolution of corrosion products, which makes the protective effect of the corrosion product layer weaker. The change of pH value not only affects the corrosion mechanism of AZ31, but also alters the concentration of NH_(4)^(+) ions in the solution, which further influences the corrosion product layer of AZ31, and finally makes the corrosion of AZ31 change significantly.

Fluorescent Switch Behavior of 1, 2-Bis(4-pyridyl) Ethylene Controlled by pH in Aqueous Solution

With the decrease of pH value from 8.45 to -1.0, the UV-Vis absorption and fluorescent spectra of 1,2-bis（4-pyridyl） ethylene（BPE） took on the same changing trend at four different successive pH stages： 8.45--7.20, 7.20--5.62, 5.62--2.60, and 2.60--1.0, namely, no change, decrease, increase, and decrease again. Among these, in a range of 7.20--5.62, the fluorescence wavelength blueshifted from 418 to 359 nm, but the UV-Vis absorption wavelength, in contrast, redshifted from 285 to 298 nm. The fluorescence intensity of BPE had a drop even to quench upon a decline in the pH value from 2.60 to -1.0 probably owing to its cation-re interaction to reduce the π electron cloud density of BPE. Two dissociation constants, pKa1（4.30±0.01） and PKa2（5.65±0.04）, were obtained based on fluorescence data. The changes of fluorescence spectra indicate that BPE has ＂oft-on-off＂ switch behavior. The fluorescent spectra of BPE were nearly independent on the presence of α- and β-cyclodextrins.

Quantitative Analysis of the Relationship between Ruminal Redox Potential and pH in Dairy Cattle: Influence of Dietary Characteristics

The ruminal redox potential (Eh) can reflect the microbiological activity and dynamics of fermentation in the rumen. It might be an important indicator of rumen fermentation in combination with pH. However, the ruminal Eh has been rarely studied in dairy cows due to the difficulty of its measurement, and the relationship between ruminal Eh and pH is not clear. The objective of this study was to investigate the relationship between ruminal Eh and pH of dairy cows by meta-analysis of systematic measurements from different experiments. A database was constructed from 22 experiments on cannulated dairy cattle including 57 dietary treatments. The ruminal pH and Eh were measured without air contact between 0 and 8 h post-feeding. The results demonstrated a quadratic correlation between ruminal Eh and pH with a reliable within-animal variation (Eh = -1697 + 540.7 pH -47.7 pH2, nobservation = 70, nanimal = 26, P Eh, but not always to the same extent. Some of them still influenced the relationship between ruminal Eh and pH. While the mechanism of the interaction between ruminal Eh and pH remains to be elucidated, it would be interesting to associate Eh to microbial profile, ruminal VFA concentration and milk production performance in future studies.

Spectrophotometric Determination of the pKa, Isosbestic Point and Equation of Absorbance vs. pH for a Universal pH Indicator

The pKa and the isosbestic point of the universal pH indicator Carlo Ebra 1-11 (catalog number 45712) were determined using UV-Vis spectrophotometry. Aqueous buffer solutions with pHs ranging from 3.83 to 10.85 were mixed. Four methods—two graphical and two mathematical— were used to estimate the acid dissociation constant (pKa) and isosbestic point using absorbance measurements. The equation for the dependence of the absorbance on pH at λ = 600 nm was obtained using calibration curves. The resulting average pKa of the four methods was 8.277 with a standard deviation of 0.1728. The results obtained using the mathematical methods were very similar, with a deviation of 0.0014;the average pKa determined using these methods was 8.263 ± 0.001. The literature contains no previous reports of the pKa of this indicator. The isosbestic point occurs at a wavelength of 494 nm, with an absorbance of 0.46.

Randomized Clinical Study, Comparative of Parallel Groups, to Evaluate the Effectiveness of Three Preparations of Potassium Citrate in Producing an Increase in Urinary pH in Patients with a History of Kidney Stones

Background: A very strict control of urinary pH is recommended to maintain it between 5.5 and 6.2, preventing formation or recurrence of crystals. Kidney stones are a common problem, with a high rate of recurrence, not altered by the success of surgery. Medical treatment prevents recurrence. Potassium Citrate inhibits crystallization of calcium salts. It influences calculogenesis by increasing urinary citrates and alkalinizing the urine. Purpose: to evaluate the similarity in the effect of three K citrate products, K citrate reference product Urocit&#174;10 mEq, and K citrate from Laboratorios LETI S.A.V., 10 mEq and 15 mEq, on urinary pH. Materials and Methods: We carried out a prospective, randomized study of three parallel groups. We admitted female and male patients with history of kidney stones or evidence of lithiasis (grit, microlithiasis) in the renal echosonogram. Laboratory assessments: urine, 24-hour urine, urinary pH, Calcium, uric acid, Phosphorus, Sodium, protein and urinary creatinine at times: start, day 7, day 21, 30 of treatment. Results: all three products produced a slight increase in urinary pH in the simple urine test and 24-hour urine, with no differences between groups or their logarithmically transformed means and their CI95, which did not exceed the range between 80% and 125%. Conclusions: K Citrate, 10 mEq and 7.5 mEq, from Laboratorios LETI, S.A.V., at a dose of 30 mEq daily in patients with history of kidney stones are equivalent to the reference product Urocit&#174;, in its effects on urinary pH in 24-hour urine, and in the simple urine test.

A pH indicator film based on sodium alginate/gelatin and plum peel extract for monitoring the freshness of chicken

To monitor the freshness of chicken,a pH-sensitive film based on sodium alginate,gelatin,and plum peel extract(SGPE)was created.Thickness,color,water contact angle,mechanical characteristics,water content,water vapor transmission,light transmission,and pH sensitivity were used to evaluate the performance of the film sample.SEM and FTIR graphs demonstrated that adding plum peel extract made the SGPE film’s internal structure more denser and increased its mechanical property,while decreasing the water contact angle,water content,and WVP value.The color of the SGPE15 film clearly changed from red to yellow-green in various buffer solutions(pH=1-14),demonstrating more pH sensitivity than the SG,SGPE5,and SGPE10 films.On day 6,when checking the freshness of chicken kept at 4℃,the SGPE15 film’s color changed from orange-pink to yellow-green with TVB-N level beyond the allowable limit(15 mg/100 g).The result revealed that the SGPE film might be applied to monitor the freshness of chicken breast flesh.