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Background. Imbalances of vagina microbiota in pregnant women entail the development of bacterial vaginosis and candidal vulvovaginitis. Lactobacterial strains modulate pro-inflammatory epithelium responses to enhance resistance, which renders lactobacteria promising agents in pregnant women with elevated pH.Objectives. Assessment of the lactobacterial impact on vaginal microbiota and the course of gestation and labour.Methods. A total of 261 pregnant women were examined and separated by cohorts according to pH of vaginal fluid: ≥4.5 in cohort 1 (n = 147), n = 114). Cohort 1 had age 29.9 (4.6) years, cohort 2 — 29.0 (4.6) years, p = 0.55. Screening: at weeks 11–14, 18–21, 30–34 and 36–41 of gestation we performed vaginal pH-metry, cervicometry, determined opportunistic pathogens and lactobacteria with mass spectrometry. Cohort 1 received lactobacteria. Statistical analyses were performed with Statistica 10.Results. In cohort 1 receiving lactobacteria, the number of women devoid of opportunistic flora increased from 31.29 to 43.53%. In cohort 2 not receiving lactobacteria, this number decreased from 53.51 to 35.09%. In cohort 1, L. jensenii (correlates with bacterial vaginosis rate) was primarily isolated in 9.52% women, and in 14.91% — in cohort 2. The rate of L. jensenii increased to 14.96% in cohort 1 (receiving lactobacteria) and decreased to 3.51% in cohort 2 (not receiving lactobacteria). A higher L. jensenii rate correlated with absent growth of opportunistic pathogens. Increasing the rate of L. crispatus (suppresses opportunistic pathogens) to 14.96% in cohort 1 lead to a 1.9-fold diminishing of active opportunistic flora. An increase of L. crispatus from 7.02 to 30.7% in cohort 2 supressed active opportunistic growth 3.9-fold at a normal baseline pH. Cervicometry values were invariant between the cohorts. Pregnancy complications were not observed under abundant lactobacterial growth. The risk of gestation loss occurred in 1.4% of women in cohort 1 and in 10.5% — in cohort 2. Abnormal labour and premature rupture of foetal membranes were more frequent in cohort 2.Conclusion. With a less favourable premorbid condition in cohort 1, vaginal changes with background lactobacterial therapy facilitate gestational health in pregnancy. Many “sterile” niches, especially the maternal generative passages, represent active low biomass environments inhabited by unique typical maternal microflora. Most remarkable is the correlation between health of vaginal microbiota and abnormal labour.

Phosphorus (P) discharge from wastewater treatment plants into the environment contributes to eutrophication issues. Reactive media filters represent an effective, simple and cost-effective solution to decrease the P content. Previous research used various experimental designs and often synthetic wastewater, making assessment of real-world performance difficult. This study assesses the impact of the hydraulic retention time (HRT) on P removal using real wastewater to refine design criteria for full-scale installations. Four media were compared in column experiments for >200 days. Different HRTs were applied and initially the media achieved low P effluent concentrations of >0.1 mg/L PO4–P, increasing over time. Best P removal was observed for the highest HRT with on average >99%. HRT was seen to be the driving factor for P removal rather than media capacity. Three of the four materials showed pH levels above 12 initially, decreasing over time. Water quality parameters, including organics, solids and metals, were monitored. In-depth analysis confirmed formation of calcium phosphate precipitation on the media's surface. The results suggest the importance of an optimal HRT to achieve high P removal and show that the reactive media application is an appropriate technology for P removal on small sites if the elevated pH is addressed.

The aim of this investigation was to evaluate the impact of multiple freezing and thawing cycles on the physicochemical properties of Nile tilapia fillets. For this purpose, 72 fresh Nile tilapia fillets were packed and stored in a freezer at -18 °C. The frozen samples were submitted to five freeze-thaw cycles; in each cycle, the freezer was switched off during 14 hours. The consecutive freeze-thaw cycles resulted in a fillet’s total weight loss of 9.48%, with a quadratic regression (P < 0.0001) for thaw loss, with a greater loss percentage in cycle 3 (2.68%). pH values differed between the cycles (P < 0.0001), being observed an increment in this parameter only from cycle 4. The lipid oxidation remained constant in cycles 1, 2, 4 and 5, however in cycle 3 the lowest value (P < 0.0002) was observed. The luminosity, and intensity of the red and yellow colours increased linearly (P < 0.0001) as the cycles increased. Thereby, the tilapia fillets’ quality were adversely affected by the freezing cycles. The unfavourable alterations included weight loss, lipid oxidation and elevated pH, as well as the increasingly augmentation of brightness and red and yellow colorations of fillets as the progressive cycles occurred.

Non-healing, chronic wounds place a huge burden on healthcare systems as well as individual patients. These chronic wounds especially diabetic wounds will ultimately lead to compromised mobility, amputation of limbs and even death. Currently, wounds and limb ulcers associated with diabetes remain significant health issues; the associated healthcare cost ultimately leads to the increased clinical burden. The presence of diabetes interrupts a highly coordinated cascade of events in the wound closure process. Advances in the understanding of pathophysiological conditions associated with diabetic wounds lead to the development of drug delivery systems which can enhance wound healing by targeting various phases of the impaired processes. Wound environments typically contain degradative enzymes, along with an elevated pH and demonstrate a physiological cascade involved in the regeneration of tissue, which requires the application of an effective delivery system. This article aims to review the pathophysiological conditions associated with chronic and diabetic wounds. The delivery systems, involved in their treatment are described, highlighting potential biomaterials and polymers for establishing drug delivery systems, specifically for the treatment of diabetic wounds and the promotion of the associated mechanisms involved in advanced wound healing. Emerging approaches and engineered devices for effective wound care are reported. The discussion will give insight into the mechanisms relevant to all stages of wound healing.

In this paper, a special case for bioequivalence evaluation of oral formulations is discussed. Drug formulations with different forms of active moieties (e.g., free base and salt) may yield different dissolution characteristics and, thus, differ in absorption at elevated gastric pH. However, routine bioequivalence trials using subjects with normal gastric pH (i.e., ~ 1) may fail to identify these differences because dissolution/absorption profiles of the two formulations at normal gastric pH are similar. In the case of palbociclib, it is confirmedthat the free base and salt formulations showed different absorption in patients with different gastric pH. Significant reduction in drug absorption was observed only in patients with elevated gastric pH using free base formulation. The discovery that the free base had significantly reduced absorption hinged on the inclusion of enough patients with elevated gastric pH to detect a difference in a bioequivalence trial. This raises a concern, as demonstrated through simulation, that dissolution/absorption differences in other formulations could be missed in routine bioequivalence trials. Aside from differences in active pharmaceutical ingredients (APIs), other factors, such as changes in excipients or manufacturing methods, may also lead to exposure differences between formulations at elevated gastric pH. For formulations containing different forms of the same active moiety or the same API and showing different dissolution profiles at elevated pH (i.e., pH ~ 4–6.8), evaluation of bioequivalence with gastric pH modulators (e.g., a H2 blocker) in addition to routine bioequivalence assessments may help to ensure therapeutic equivalence in patients with elevated gastric pH.

Myoglobin (Mb) is a sarcoplasmic heme protein present in muscle cells, which acts as a short–term oxygen (O2) reserve in the muscle tissue. After slaughtering and exsanguination, Mb is the major pigment that provides the red color in meat. The concentration of Mb together with its redox state are two pivotal factors that determine meat color. The elevated pH of dark–cutting beef can affect both physical and biochemical properties resulting in decreased oxygenation. The darkening observed in high ultimate pH (pHu) beef concerns meat processors as color is the initial attribute that impacts on the purchase. Thus, any atypical meat color (i.e., loss of brightness) reduces consumer interest in the product. Several studies have demonstrated that immunological castration is effective in preventing both aggressive behavior and undesirable dark–cutting of bull meat. However, little information is available on the effects of processing techniques that limit the oxidation of ferrous iron (Fe2+), Mb or promote metmyoglobin (MMb) reduction in dark–cutting beef. Because of the importance of color to fresh beef marketability, this review aimed at overviewing the significance of pHu in beef color and color stability and to discuss new alternatives for improving and assessing the beef color of dark–cutting beef, especially in Nellore bulls and their crossbreds, which are widely used in beef cattle production in Brazil.

Until the large-scale application of artificial fertilizer in the 20th century, heathlands were a characteristic and essential element of the agricultural system on sandy soils in NW Europe. Attempts to increase the total area of the small remaining heathlands by converting agricultural areas are only partially successful. Reasons for such low success rates are (1) excessive soil nutrient concentrations, (2) elevated pH, (3) a low local availability of diaspores of characteristic biota, and (4) an ill-adapted soil community. The present review discusses these topics in more detail and evaluates potential solutions. Based on this review in combination with results of a long-lasting large-scale field experiment, we evaluate the prospects of alternative techniques to restore heathlands from agricultural fields.

International audience; 99Tc will be present in significant quantities in radioactive wastes including intermediate-level waste (ILW). The internationally favored concept for disposing of higher activity radioactive wastes including ILW is via deep geological disposal in an underground engineered facility located ∼200–1000 m deep. Typically, in the deep geological disposal environment, the subsurface will be saturated, cement will be used extensively as an engineering material, and iron will be ubiquitous. This means that understanding Tc biogeochemistry in high pH, cementitious environments is important to underpin safety case development. Here, alkaline sediment microcosms (pH 10) were incubated under anoxic conditions under “no added Fe(III)” and “with added Fe(III)” conditions (added as ferrihydrite) at three Tc concentrations (10–11, 10–6, and 10–4 mol L–1). In the 10–6 mol L–1 Tc experiments with no added Fe(III), ∼35% Tc(VII) removal occurred during bioreduction. Solvent extraction of the residual solution phase indicated that ∼75% of Tc was present as Tc(IV), potentially as colloids. In both biologically active and sterile control experiments with added Fe(III), Fe(II) formed during bioreduction and >90% Tc was removed from the solution, most likely due to abiotic reduction mediated by Fe(II). X-ray absorption spectroscopy (XAS) showed that in bioreduced sediments, Tc was present as hydrous TcO2-like phases, with some evidence for an Fe association. When reduced sediments with added Fe(III) were air oxidized, there was a significant loss of Fe(II) over 1 month (∼50%), yet this was coupled to only modest Tc remobilization (∼25%). Here, XAS analysis suggested that with air oxidation, partial incorporation of Tc(IV) into newly forming Fe oxyhydr(oxide) minerals may be occurring. These data suggest that in Fe-rich, alkaline environments, biologically mediated processes may limit Tc mobility

A series of the experiments were carried out on the Nandan lead-zinc tailings management and one bioleaching method was proposed with the purpose of recovering the valuable metal such as Zn. Firstly, multi-elements analysis was performed to provide theoretical data. Secondly, the effect of the pH on the bacterial growth and Fe2+ oxidation was investigated. The results showed that pH at 2.5 was the optimum for the bacteria. The concentration of the bacteria at pH 2.5 can be up to 9.3×107 cells/mL. Finally, the bioleaching treatment was performed to study the potential of bioleaching the tailings. The data illustrated that the method of bioleaching can extremely recover metals such as zinc from the tailings, which provided novel insights into metal recycling.

Chronic, non-healing wounds place a significant burden on patients and healthcare systems, resulting in impaired mobility, limb amputation, or even death. Chronic wounds result from a disruption in the highly orchestrated cascade of events involved in wound closure. Significant advances in our understanding of the pathophysiology of chronic wounds have resulted in the development of drugs designed to target different aspects of the impaired processes. However, the hostility of the wound environment rich in degradative enzymes and its elevated pH, combined with differences in the time scales of different physiological processes involved in tissue regeneration require the use of effective drug delivery systems. In this review, we will first discuss the pathophysiology of chronic wounds and then the materials used for engineering drug delivery systems. Different passive and active drug delivery systems used in wound care will be reviewed. In addition, the architecture of the delivery platform and its ability to modulate drug delivery are discussed. Emerging technologies and the opportunities for engineering more effective wound care devices are also highlighted.

Honey is a natural food item produced by honey bees. Ancient civilizations considered honey as a God gifted prestigious product. Therefore, a huge literature is available regarding honey importance in almost all religions. Physically, honey is a viscous and jelly material having no specific color. Chemically, honey is a complex blend of many organic and inorganic compounds such as sugars, proteins, organic acids, pigments, minerals, and many other elements. Honey use as a therapeutic agent is as old as human civilization itself. Prior to the appearance of present day drugs, honey was conventionally used for treating many diseases. At this instant, the modern research has proven the medicinal importance of honey. It has broad spectrum anti-biotic, anti-viral and anti-fungal activities. Honey prevents and kills microbes through different mechanism such as elevated pH and enzyme activities. Till now, no synthetic compound that works as anti-bacterial, anti-viral and anti-fungal drugs has been reported in honey yet it works against bacteria, viruses and fungi while no anti-protozoal activity has been reported. Potent anti-oxidant, anti-inflammatory and anti-cancerous activities of honey have been reported. Honey is not only significant as anti-inflammatory drug that relieve inflammation but also protect liver by degenerative effects of synthetic anti-inflammatory drugs. This article reviews physico-chemical properties, traditional use of honey as medicine and mechanism of action of honey in the light of modern scientific medicinal knowledge.

The lowland Maya city of Nixtun-Ch'ich' (Peten, Guatemala) exhibits an atypical gridded layout featuring quadrilateral blocks of architectural construction, established in the Middle Preclassic period (~ 800–500 BCE). Early levels of some excavated structures revealed unusual dark-colored, sticky sediments used as architectural footings overlying limestone bedrock and as adhesives for binding construction stones. Physical, mineralogical, and soil nutrient (chemical) properties of two samples of this material were analyzed. The samples were found to be highly organic (high %LOI), and composed primarily of smectite clay. They are characterized by low green strength, marked swelling when mixed with water, and corresponding shrinkage on drying, suggesting low load-bearing capacity. Chemical analyses revealed a slightly elevated pH of 7.8 and high levels of six soil nutrients but low phosphorus, likely making the material unsatisfactory for agriculture. We conclude that these sticky organic clays, probably of lacustrine origin, functioned as bonding agents in early architectural construction.

Either naturally occurring process or human activities may have a significant impact on the quality of sub-surface waters which further limit its use. Multivariate statistical techniques such as factor analysis (FA), cluster analysis (CA) were applied for the evaluation of spatial variations and the interpretation of ground water quality data around Bacheli and Kirandul area. The major anions, cations and heavy metals were determined for each of 20 samples collected in pre-monsoon seasons. Hydrochemical parameters like EC, pH, TDS, TH, TA, Na+, K+, Ca2+, Cl-, F-, SO42-, As, Sb, Se, Pb, Cd, Zn, Cu were estimated in pre monsoon and post monsoon seasons. Different geochemical controls of the investigated parameters were also assessed. Factor 1 explains 33.47% of the total variance and indicates atmospheric controls and silicate mineral weathering process. Factor 2 explains 13.83% of total variance, indicating silicate mineral weathering process resulting in elevated pH. Generally, water types tend towards magnesium-bicarbonate-chloride.

The present study sought to identify the structural determinants of aspartic protease structural stability and activity at elevated pH. Various hypotheses have been published regarding the features responsible for the unusual alkaline structural stability of renin, however, few structure-function studies have verified these claims. Using pepsin as a model system, and renin as a template for functional and structural alkaline stability, a rational re-design of pepsin was undertaken to identify residues contributing to the alkaline instability of pepsin-like aspartic proteases in regards to both structure and function. We constructed 13 mutants based on this strategy. Among them, mutants D159 L and D60A led to an increase in activity at elevated pH levels (p ≤ 0.05) and E4V and H53F were shown to retain native-like structure at elevated pH (p ≤ 0.05). Previously suggested carboxyl groups Asp11, Asp118, and Glu13 were individually shown not to be responsible for the structural instability or lack of activity at neutral pH in pepsin. The importance of the β-barrel to structural stability was highlighted as the majority of the stabilizing residues identified, and 39% of the weakly conserved residues in the N-terminal lobe, were located in β-sheet strands of the barrel. The results of the present study indicate that alkaline stabilization of pepsin will require reduction of electrostatic repulsions and an improved understanding of the role of the hydrogen bonding network of the characteristic β-barrel.

We report the design and characterization of a de novo electrogelation protein comprised of a central spider silk glue motif flanked by terminal pH-triggered coiled-coil domains. The coiled-coiled domains were designed to form intramolecular helix bundles below a sharply-defined pH-trigger point (~pH 5.3), while the spider silk glue protein, owing to its substantial Glu content, serves both as an anionic electrophoretic transport element at neutral and elevated pH and as a disordered linker chain between the associated helix bundles at reduced pH. We show that in an electrochemical cell, a solution of these telechelic proteins migrates toward the anode where the terminal coiled-coil domains are triggered to form coiled-coil assemblies that act as transient crosslinks for the e-gel state. Upon cessation the current, the coiled-coil domains become denatured and the e-gel transforms back into a fluid solution of polypeptides in a fully reversible manner. This simplified triblock protein design mimics many of...

Biohydrometallurgy has broad application prospect in the treatment of low-grade nickel sulfide ore. However, quite a number of nickel sulfide deposits are associated with basic gangue minerals such as contain olivine, serpentine. The high basic gangue minerals will lead to a higher acid consumption and make it difficult to bioleach at pH below 2.5. It is crucial to improve processes and adapt bacteria with this kind of ore. This paper reviews the experimental researches and industrial applications for bioleaching of the high acid consumption nickel sulfide ores. It is suggested that bioleaching at elevated pH will have similar leaching rate compared with pH below 2.5, meanwhile the cost will be decreased remarkably due to a lower acid consumption and less dissolved impurity ions.

This chapter identifies animal diseases that are host specific and reviews the effects of various human diseases on animals. It also identifies history, etiologic, human Infection, diagnosis, public health aspects and therapeutic aspects of each disease important to epidemiology and prevention. Vibrio parahaemolyticus infection is a principal cause of foodborne disease outbreaks and a potential health hazard to seafood consumers throughout the world. The clinical response in V. parahaemolyticus gastroenteritis is relatively mild and self-limiting in most cases. Various agar and broth formulations have been examined for recovering V. parahaemolyticus from foods using vibriostatic constituents, increased NaCl concentration, and elevated pH as selective agents. The public health relevance of V. parahaemolyticus foodborne infection involves both basic consumer education to highlight the risk associated with eating raw seafoods and the observance of the principles of sanitation and hygiene in seafood preparation, especially of shellfish.

A vast array of organisms is known thriving in high pH environments. The biotechnological, medical, and environmental importance of this remarkable group of organisms has attracted a great deal of interest among researchers and industrialists. One of the most intriguing phenomena of alkaliphiles that engrossed researchers’ attention is their adaptation to high pH and ability to thrive in the “extreme” condition which is often lethal to other organisms. Studies made in this line revealed that alkaliphiles deployed a range of adaptive strategies to overcome the various challenges of life in high pH environments. This chapter highlights some of the challenges and the most important structural and functional adaptations that alkaliphiles evolved to circumvent the hurdles and flourish in alkaline habitats. The fascinating alkaliphiles’ pH homeostasis that effectively maintains a lower cytoplasmic pH than its extracellular environment and the remarkable bioenergetics that produce ATP much faster than non-alkaliphiles systems are reviewed in detail. Moreover, the adaptive mechanisms that alkaliphiles employ to keep the structural and functional integrity of their biomolecules at elevated pH are assessed.

Recently, the mineral carbonation via the reaction of CO2 with saline aquafers received much attention as one of the most promising ways for geologic CO2 storage. This paper reports microstructure and carbon storage capacity of hydrated magnesium carbonates (HMCs) synthesized from different sources, i.e., reject brine and commercial Mg(OH)2 slurry, and under different conditions, i.e., pH (8–14) and Mg(OH)2:CO2 molar ratio (1:1–1:7). Results show that dypingite (Mg5(CO3)4(OH)2·5H2O) is the main phase forming at lower Mg(OH)2:CO2 ratios. An increase in the Mg(OH)2:CO2 ratio and/or pH leads to the precipitation of nesquehonite (MgCO3·3H2O). A unique “house of cards” texture, involving formation of the rosette-like dypingite flakes on the surface of nesquehonite needles, is discovered under elevated pH and Mg(OH)2:CO2 ratios. HMCs synthesized from reject brine exhibit a much higher carbon storage capacity of 82.6% than that produced from the commercial Mg(OH)2 slurry (43.7%). Findings from this study advance understanding of mineral recovery from reject brine and the capture and long-term storage of CO2 in the form of HMCs.

The effects of changes in pH above and below the natural pH of milk (ca 6.6) on the casein micelle size and the gelation properties of the pH adjusted and restored samples were investigated. The size of casein micelles increased at pH 7.0 and 7.5, then started to decrease above pH 8.5. It is postulated that at pH below 8.5 the casein micelles swell, while elevated pH causes their dissociation. Conversely, the size of casein micelles decreased on acidification to pH 5.5 and increased when the pH dropped below 5.5, due to the shrinkage of casein micelles at lower pH before their aggregation at pH below 5.5. In response to neutralising treated milk back to normal milk pH of 6.6, it was found that the casein micelle size of treated milk with a narrow range of pH change between 6.0 and 7.0 was reversible, while beyond this range the structure of casein micelles became irreversible. The restoration of casein micelle size was followed by the restoration of some parameters such as soluble calcium, ethanol stability, and milk whiteness. Acid-induced gelation did not change the elastic modulus, while rennet-induced gelation was affected by initial milk pH. In reference to the size of reversible range elastic modulus (G’) of acid or rennet gels made from restored milk, the sizes were similar to control milk after 6 h of gelation.

This work investigated the effects of Fe3+, H+ and adsorbed leaching bacteria on the bioleaching of pentlandite. Collectively, an integrated model for the oxidation and decomposition of pentlandite was built to describe the behaviors of different components in a bioleaching system. Proton ions and ferric ions could promote the break and oxidation of Ni-S and Fe-S bonds. The iron-oxidizing microorganisms could regenerate ferric ions and maintain a high Eh value. The sulfur-oxidizing microorganisms showed significant importance in the oxidation of polysulfide and elemental sulfur. The atoms in pentlandite show different modification pathways during the bioleaching process: iron transformed through a (Ni,Fe)9S8 &rarr, Fe2+ &rarr, Fe3+ &rarr, KFe3(SO4)2(OH)6 pathway, nickel experienced a transformation of (Ni,Fe)9S8 &rarr, NiS &rarr, Ni2+, sulfur modified through the pathway of S2&minus, /S22&minus, &rarr, Sn2&minus, S0 &rarr, SO32&minus, SO42&minus, During bioleaching, a sulfur-rich layer and jarosite layer formed on the mineral surface, and the rise of pH value accelerated the process. However, no evidence for the inhibition of the layers was shown in the bioleaching of pentlandite at pH 3.00. This study provides a novel method for the extraction of nickel from pentlandite by bioleaching at elevated pH values.

Pregnant women in sub-Saharan Africa exhibit a particularly high incidence of urinary tract infections (UTIs) which can lead to severe kidney damage and infant mortality. In order to overcome the access barrier to healthcare experienced in these developing countries, a low-cost test strip for UTI screening is being developed through a small-scale hand stamping process. By minimizing the number of testing parameters to three, these test strips become accessible to community health workers (CHWs) who have limited education and training. These individuals act as liaisons between the formal health care system and rural communities that are geographically dispersed and culturally distinct. Furthermore, CHWs will be the primary mode for test strip distribution, representing the last mile delivery channels for the product. Filter paper adhered to PVC strips is utilized as the principal substrate for chemical deposition onto the test strips in which three common biomarkers of UTIs are detectable in urine: leukocytes, nitrites, and elevated pH. The leukocyte and nitrite assays are both produced through a single step diazonium coupling with an aromatic amine, while pH can be detected with bromophenol red. Each assay exhibits a rapid, visible color change in the presence of infection markers with a defined intensity gradient that can be experimentally verified. Furthermore, to prevent dispersion across all three stamped regions, a hydrophobic barrier in the form of thin PVC strips has been introduced to maintain color change integrity. Beyond the detection of UTIs, this affordable and effective urinalysis technology can be expanded to screen for a myriad of treatable diseases to improve the accessibility of healthcare in developing nations, particularly in rural communities.

Injectable hydrogels ideally are low-viscosity liquids when being pushed through a syringe needle and quickly form gels after injection. Physiologically triggered injectable hydrogels based on stimuli-responsive polymers induce sol to gel transitions via pH or temperature alteration, however, such mild environmental stimuli are often prone to be inefficient for triggering the rapid and drastic transition from low-viscosity liquids to form-stable hydrogels. Here, an enzyme mediation strategy to regulate, transmit, and amplify the environmental stimuli is presented for efficient formation of hydrogels with high injectability and stability. The urease-regulated biocatalytic reaction initially inhibited at slightly acidic pH and room temperature is integrated with a pH-responsive system of aqueous N-palmitoyl chitosan (NPCS), acquiring temporally modulated high injectability. After injection to physiological environments, the enzyme activity is significantly enhanced with the elevated pH and temperature, resulting in fast enzymatic generation of a base, which in turn triggers the efficient hydrogelation of aqueous NPCS.

Formation of soluble, heat stable whey protein (WP) particles may be achieved via caseins and their chaperone like activity. The aim of this study was to establish effects of caseins on the properties of heat induced WP aggregates. Concentrated dairy protein mixtures (10% total-solids) were prepared with various casein:WP ratios (5:95–30:70) at adjusted pH (5.7–7.5) and heated to 80–120 °C, under a constant shear (500 s−1). Increasing casein fraction at higher pH reduced the average size of WP aggregates and the surface hydrophobicity with simultaneous reduction in apparent viscosity at pH 6.7. WP denaturation was minimal when 30% casein was included in the dispersions. Inhibition of WP denaturation at elevated pH with inclusion of caseins may be attributed to a chaperon like activity of the casein. Thus, by increasing pH and the casein content in the system it was possible to form nano-size whey protein particles.

Oligosaccharides (OS) production using wood prehydrolysis liquor (PHL) is a crucial subject with significant economic and environmental benefits for wood biorefinery. However, this is a challenging task due to the presence of a diverse palette of lignin-derived contaminants. In this work, lignin contaminants were classified into macro-lignin particles (MLPs), amphiphiliclignin derivatives (ALDs) and small lignin fragments (SLFs) based on their colloidal and molecular behaviors. Accordingly, a process was developed to destabilize ALDs and MPLs synergistically by applying polycations at an elevated pH, which achieved 57.8% lignin removal. The remaining SLFs were adsorbed by macroporous resin with pore size of 20 nm at least, leading to 95.2% of final lignin removal and 66.6% of OS recovery. This study has both scientific and practical significance for wood biorefinery because of the low cost of chemicals employed and the regeneration ability of macroporous resin.

The coexistence of arsenic (As) and fluoride (F) in some underground waters creates challenges in the simultaneous removal of these two toxic elements. This study investigates the effect of fluoride at different molar ratios of fluoride to arsenic (As) ( R F:As ) on the removal of arsenic [i.e., arsenite (As(III), arsenate (As(V)] by freshly-prepared aluminum hydroxide (AlOxHy), and that of arsenic at different molar ratios of arsenic to fluoride ( R As:F ) on fluoride removal. In single pollutant solutions, the removal of neutral As(III) is independent on pH at R As(III):Al ≤ 0.70:1 and is much lower than that of As(V). The optimum As(V) removal is at weak acidic pH of 5 and 6 whereas that of fluoride is at pH 7 and 8. Fluoride at R F:As(V) > 35:1 significantly impairs the removal of As(V) with more significant inhibition at elevated pH. The negatively-charged As(V) inhibits fluoride removal to a larger extent than the neutral As(III) does. The adverse effect of fluoride on As(V) removal is mainly attributed to the lowered ζ -potential, which is controlled by the combined effects of pH and R F:As(V) . In relative terms, the removal of fluoride is highly pH dependent, although R As(V):F does show some effects. The oxidation of As(III) to As(V) and the adjustment of pH to weak acidic range is well preferred to achieve the simultaneous removal of As and F by AlOxHy adsorption.

A study was undertaken to assess the effects of anthropogenic particles on the pH, electrical conductivity (EC), and magnetic susceptibility (MS) of anthropogenic soils in Detroit, Michigan. The results showed that ^Au horizons of anthropogenic soils at residential demolition, industrial, and fly ash–impacted sites were distinguishable from A horizons of native soils (background level). Anthropogenic soils were higher by 1 pH unit or more, had an EC three to four times background level, and were characterized by an elevated MS that was up to 20 times background. Anthropogenic soils at residential demolition sites had a uniquely high EC signature, whereas those at industrial sites were distinguished by anomalously high MS. Fly ash–impacted soils differed from native soils but were similar to other anthropogenic soils. Analyses of reference artifacts suggest that the elevated pH of anthropogenic soils was caused by calcareous building material wastes, whereas elevated EC were the result of both calcareous and ferruginous wastes. Elevated MS were attributable to ferrimagnetic materials such as corroded iron nails, coal ash and cinders, and metalliferous slag. Analyses of “artificial soils” indicated that there were measurable effects on pH, EC, and MS even with low concentrations of anthropogenic microparticles (

Although immobilized trypsin is a viable alternative to the free one in solution for producing protein hydrolysates, the change of selectivity introduced by immobilization is unclear. In this study, we compared the selectivity of free and immobilized trypsin towards different cleavage sites of β-lactoglobulin (β-Lg) with a focus on the impact of environmental pH. Both free and immobilized trypsin exhibited greater accessibility to native β-Lg at elevated pH (from pH 7.2 to 8.7). Additionally, free trypsin preferred to attack cleavage sites located at the C-terminus at pH 7.8, whereas an opposite preference for the N-terminus was observed at pH 8.7. Regarding the immobilized trypsin, the pH did not significantly influence its preference for the C- or N-terminus. Generally, immobilization of trypsin resulted in more focused cleavage within its specificity during the initial stage of hydrolysis, and some peptides were formed more rapidly by the immobilized trypsin.

Nilgirianthus ciliatus Nees is used in traditional Indian system of medicine for the treatment of numerous physiological disorders. Previous investigations revealed that various bioactive compounds have been isolated from this plant for the treatment of various disorders. But these compounds may be unstable in gastrointestinal tract due to the elevated pH and harsh condition that renders the bioactive compounds ineffective. In order to improve the pharmacokinetic and pharmacodynamic properties of various drugs, nanoparticles were developed by various techniques. Nanoformulation of ethanolic extract of Nilgirianthus ciliatus was prepared by solvent evaporation technique using gelatin as carriers and evaluated its antidiabetic effects in L6 myoblasts and 3T3L1 adipocytes. The mean particle size of plant extract loaded gelatin nanoparticles was approximately 110 nm and they are spherical in shape on observation by transmission electron microscope. The ethanolic extract of Nilgirianthus ciliatus was encapsulated with 80% efficiency in gelatin biodegradable nanoparticles formulation. MTT assay was also performed to study the toxicity of nanoformulation; the nanoencapsulated form does not produce any toxicity upto 1000 μg/ml concentrations. Nanoformulation of Nilgirianthus ciliatus was evaluated for its antidiabetic activity by glucose uptake assay in L6 cells and anti-adipogenic assay in 3T3L1 preadipocytes. The plant extracts loaded nanoparticles showed significant antidiabetic effect in both assays in a dose dependent manner when compared to the ethanolic extract. After nanoencapsulation the aqueous dispersion is more, this may be the reason for the better antidiabetic effect. Therefore nanoencapsulated Nilgirianthus ciliatus could be considered as potential antidiabetic drug.

To investigate the effects of boron on growth performance and meat quality, 10-day-old Africa ostrich chicks were randomly divided into 6 groups with 6 replicates in each group. For 80 days, birds in the treatments were fed the same basal diet but given different concentrations of boron-supplemented water. The highest final BW (33.4 ± 0.30 kg), ADFI (376 ± 1.83 g), and ADG (224 ± 1.01 g) appeared in the group receiving 160 mg/L boron (group 4). 160 mg/L boron also decreased drip loss (2.20 ± 0.59), cooking loss (35.3 ± 1.14), and elevated pH value (6.13 ± 0.28) of meat (P < 0.05). Ostrich chicks in the 640 mg/L treatment group (group 6) had the lowest final BW (30.8 ± 1.05 kg) and ADG (208 ± 0.74 g) (P < 0.05). The highest ash (1.35 ± 0.01%) and pH (6.18 ± 0.03) and the lowest protein (20.4 ± 1.74%), drip loss (2.10 ± 0.76%), cooking loss (35.0 ± 0.41%), C18:1 (28.2 ± 0.65%), and C18:3ω3 (2.60 ± 0.51%) appeared in group 6 (P < 0.05) as well. Overall, the optimum concentration of 160 mg/L supplemental boron improved ostrich growth performance and meat quality; however, high concentrations of boron decreased both performance and meat quality.

Proteases are one of the most important commercial enzymes used in various industrial domains such as detergent and leather industries. The alkaline proteases as well as other detergent-compatible enzymes such as lipases and amylases serve now as the key components in detergent formulations. They break down various stains during fabric washing. The search for detergent-compatible proteases with better properties is a continuous exercise. The current trend is to use detergent-compatible proteases that are stable over a wide temperature range. Although the proteases showing stability at elevated pH have the capacity to be used in detergent formulations, their usage can be significant if they are also stable and compatible with detergent and detergent ingredients, and also able to remove protein stains. Despite the existence of some reviews on alkaline proteases, there is no specification for the use of alkaline proteases as detergent additives. The present review describes the detergent-compatible proteases tested as detergent additives. An overview was provided for screening, optimization, purification, and properties of detergent compatible proteases, with an emphasis on the stability and compatibility of the alkaline proteases with the detergent and detergent compounds, as well as stain removal examination methods.

This work addressed a hypothetical but practical scenario that includes biological oxidation and reductive dechlorination in treating groundwater containing co-mingled plume of trichloroethene (TCE), benzene and toluene. Groundwater immediately downgradient from the commonly used zero-valent iron (ZVI) has shown alkaline pH (up to 10.7). The elevated pH may influence BTEX compounds (i.e., benzene, toluene, ethyl benzene, and xylenes) biodegradation, which could also be inhibited by elevated concentrations of TCE. Data from this work suggests that the inhibition coefficients (IC) value for 100 μg/L and 500 μg/L of TCE on benzene and toluene degradation are 2.1-2.8 at pH 7.9, and 3.5-6.1 at pH 10.5. For a co-mingled plume, it appears to be more effective to reduce TCE by ZVI before addressing benzene and toluene biodegradation. The ample buffering capacity of most groundwater and the adaptation of benzene and toluene-degrading microbes are likely able to eliminate the adverse influence of pH shifts downgradient from a ZVI-PRB.

Long-term monitoring of the chemical composition of clouds (73 cloud events representing 199 individual samples) sampled at the puy de Dôme (pdD) station (France) was performed between 2001 and 2011. Physicochemical parameters, as well as the concentrations of the major organic and inorganic constituents, were measured and analyzed by multicomponent statistical analysis. Along with the corresponding back-trajectory plots, this allowed for distinguishing four different categories of air masses reaching the summit of the pdD: polluted, continental, marine and highly marine. The statistical analysis led to the determination of criteria (concentrations of inorganic compounds, pH) that differentiate each category of air masses. Highly marine clouds exhibited high concentrations of Na+ and Cl−; the marine category presented lower concentration of ions but more elevated pH. Finally, the two remaining clusters were classified as "continental" and "polluted"; these clusters had the second-highest and highest levels of NH4+, NO3−, and SO24−, respectively. This unique data set of cloud chemical composition is then discussed as a function of this classification. Total organic carbon (TOC) is significantly higher in polluted air masses than in the other categories, which suggests additional anthropogenic sources. Concentrations of carboxylic acids and carbonyls represent around 10% of the organic matter in all categories of air masses and are studied for their relative importance. Iron concentrations are significantly higher for polluted air masses and iron is mainly present in its oxidation state (+II) in all categories of air masses. Finally, H2O2 concentrations are much more varied in marine and highly marine clouds than in polluted clouds, which are characterized by the lowest average concentration of H2O2. This data set provides concentration ranges of main inorganic and organic compounds for modeling purposes on multiphase cloud chemistry.

Introduction: The antimicrobial effect of calcium hydroxide has been assigned to its capacity to produce an alkaline shift in pH. This property is affected when calcium hydroxide is combined with other substances, such as 2% chlorhexidine gel and zinc oxide, which makes the action of the paste last longer. Objective: This study assessed whether calcium hydroxide paste associated with chlorhexidine gel and zinc oxide promote pH shifts at short time intervals. Methods: Calcium hydroxide pastes prepared with three vehicles: saline solution (paste A); propylene glycol (paste B); and 2% zinc oxide chlorhexidine gel (paste C) were placed into vials containing 15 ml of deionized water. A pH meter was used to detect pH shifts of combinations in different vehicles at seven time intervals: 15 and 30 minutes; 1, 24 and 48 hours; as well as 7 and 14 days. Results: All three pastes presented a sharp increase of pH values at the first time interval and remained relatively stable at a value of about 12 from 24 hours to 7 days. After this period, the pH of pastes A and B decreased to 9.50, whereas that of paste C remained at 12. Conclusions: Pastes A and B produced a faster alkaline shift of the solution, whereas paste C kept an elevated pH for a longer time, however, differences were not statistically significant.

Two field experiments were carried out using a custom built flow-through laboratory to test the effect of elevated pH on dreissenid mussels as a potential control method. Both experiments tested the ability of dreissenid pediveligers to settle under conditions of elevated pH and the long-term survival of adult dreissenids under the same conditions. The two experimental sites had different water quality and different species of dreissenids present. The settlement of quagga mussel pediveligers at the lower Colorado River was inhibited with increasing pH. At the maximum achieved pH of 9.1, there was approximately 90% reduction compared to the maximum settlement observed in the controls. Since the settlement was almost as low in pH 8.9 as at pH 9.1, the inhibition in settlement may have been due to the presence of a precipitate formed under high pH conditions rather than the increase in background pH. No mortality of quagga mussel adults was observed in the experimental pH levels at the lower Colorado River. At San Justo Reservoir, zebra mussel settlement decreased with increasing pH. New settlement was almost entirely absent at the highest pH tested (pH 9.6). The observed mortality of adult zebra mussels was low, but did tend to increase with increasing pH. We also tested the response of adult zebra mussels to short-term exposure to very high pH levels (i.e. pH 10, 11, and 12). Adult mussels in poor physical condition experienced 90% mortality after 12 hours at pH 12. For unstressed adult zebra mussels, 90% mortality was reached after 120 hours at pH 12. Significant mortalities were also observed both at pH 10 and pH 11. From this study, we conclude that pH elevation could be used both as a preventative treatment to eliminate settlement by dreissenid mussels and as an end of season treatment to eliminate adults. The high pH treatment would have to be tailored to the site water quality to prevent formation of precipitate during treatment and to minimize corrosive action on materials of construction.

New molecular biology-based methods of bacterial identification are expected to help elucidate the relationship between colorectal cancer (CRC) and intestinal microbiota. Although there is increasing evidence revealing the potential role of microbiota in CRC, it remains unclear whether microbial dysbiosis is the cause or the result of CRC onset. We investigated the changes of intestinal environments in CRC or adenoma. We analyzed 13 groups of microbiota, 8 types of organic acids, and pH in feces obtained from the following 3 groups: individuals with CRC, adenoma, and non-adenoma. Ninety-three patients with CRC and 49 healthy individuals (22 with adenoma and 27 without adenoma) were enrolled. The counts of total bacteria (10.3 ± 0.7 vs. 10.8 ± 0.3 log10 cells/g of feces; p

The effects of pH on taxis, mortality and activation of MAP-kinase pathways in the collembolan Onychiurus yaodai were studied. The animals preferred to stay at pH 8. They were particularly stressed by a reduction in pH but were more tolerant of elevated pH. A short period of exposure to low pH led to phosphorylation of Drosophila homolog of extracellular signal-regulated kinase (ERKa) and the c-Jun N-terminal kinase (DJNK) in the animals, indicating activation of these signal transduction pathways. Our observations suggest that reduced environmental pH, even for a limited period, is potentially harmful to O. yaodai. © 2004 Elsevier GmbH. All rights reserved.

To obtain an acidic and cold-active tyrosinase, which potentially minimizes unwanted self-oxidation of tyrosinase-catalyzed catechols, including 3,4-dihydroxyphenylalanine at elevated pH and high temperature. A putative psychrophilic tyrosinase (named as tyrosinase-CNK) was identified from the genome information of the marine archaeon Candidatus Nitrosopumilus koreensis. This protein contains key tyrosinase domains, such as copper-binding domains and an O2-binding motif, and phylogenetic analysis revealed that it was distinct from other known bacterial tyrosinases. Functional tyrosinase-CNK was produced by applying a co-expression strategy together with chaperone proteins in Escherichia coli with a yield of approx. 30 mg l−1 and a purity >95 %. The purified enzyme showed optimal activity at pH 6 and 20 °C and still had 50 % activity at 0 °C. Surprisingly, the enzyme exhibited an abnormally high monophenolase/diphenolase activity ratio. The acidic and cold-adapted tyrosinase-CNK, as a new type of tyrosinase, could expand potential applications of tyrosinases including the production of catechols through minimizing unwanted self-oxidation and the modification of existing materials at low temperature.