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The objective was to simulate the characteristics of low-calcium (18.8 mg calcium/g protein) reduced-fat Mozzarella cheese by blending emulsifying salts (ES) with hot plasticized curd containing a normal level of calcium (28.8 mg calcium/g protein). Reduced-fat Mozzarella (RFM) with normal (NC) or low (LC) calcium levels were made on two separate occasions using chemical acidification of the cheese milk and plasticizing the curds (NC at pH ~ 6.0, and LC at pH 5.65) in hot water (80°C) to a curd temperature of ~ 59°C. Following plasticization, the hot molten NC Mozzarella curd was immediately blended with either trisodium citrate (TSC) or disodium phosphate (DSP) for 8 min at 59°C. TSC was added at levels (%, w/w) of 0 (NC), 0.5 (NCTSC0.5) or 1 (NCTSC1.0), and DSP at levels (%, w/w) of 0.5 (NCDSP0.5) or 1 (NCDSP1.0). The pH values of the ES-treated curds were reduced to that of the NC curd by the addition of lactic acid. The cheeses were evaluated after 12 d storage at 4°C. The mean moisture (%, w/w) and pH values of the LC and NC cheeses were 61.7 and 5.9, and 49.7 and 5.95, respectively. The addition of TSC or DSP did not affect the composition of the cheeses. The mean level of water-soluble N, as % total N, in the NCDSP1.0 cheese (9%) was notably higher than that in the other cheeses (1 - 3.6%). The mean firmness (force at 70% compression) of the cheeses decreased in the following order: NCTSC1.0 ≈ NC > NCTSC0.5 > NCDSP0.5 > NCDSP1.0 >> LC. The mean flowability of the heated cheeses, as measured by modified Olson and Price and Schreiber methods, increased in the following order: NC ≈ NCTSC0.5 < NCTSC1.0 ≈ NCDSP0.5 << NCDSP1.0 ≈ LC. The stretchability of the heated cheese, as measured by uniaxial extension at a fixed velocity, increased in the order NC ≈ NCTSC0.5 ≈ NCTSC1.0 ≈ NCDSP0.5 < NCDSP1.0 <<< LC. The results show that the functionality of low calcium RFM cheese could be partly imitated by blending 1% DSP with hot plasticized curd containing a normal calcium level. [ABSTRACT FROM AUTHOR]

The rheological properties of rennet-induced milk gels made from milk protein concentrate (MPC) solutions with αs- (i.e., αs1- + αs2-):β-casein ratios of 1.00:0.80 (MPC A), 1.00:0.70 (MPC B) or 1.00:0.87 (MPC C), each having identical concentrations of total casein (2.5%), were studied using dynamic low amplitude oscillatory rheometry. The ratio of αs-:β-casein had no significant (P > 0.05) effect on rennet coagulation time. Storage modulus (G'; index of firmness), measured 30 min after addition of rennet, decreased with increasing ratio of αs-:β-casein. Storage modulus for gels made using each of the three MPC solutions reached plateau values ~200 min after addition of rennet, with the plateau value of G' decreasing significantly (P < 0.05) as relative concentration of β-casein increased in the MPC solutions. There were no significant (P > 0.05) differences in the frequency dependence of G' in the frequency range 0.001 to 1 Hz between gels made using any of the three MPC solutions. On shearing the gels at a rate of 0.01 s-1, the value for apparent yield stress and apparent yield strain increased significantly (P < 0.05) as relative concentration of αs-casein increased in the MPC solutions. Thus, the ratio of αs-:β-casein influenced the small and large deformation rheological properties of rennet-induced milk gels. [ABSTRACT FROM AUTHOR]

The phenomenon of adenosine-to-inosine (A-to-I) RNA editing has attracted considerable attention from the scientific community due to its potential relationship to the evolution of cognition in animals. While A-to-I editing exists in all organisms with neurons, including those with primitive neuronal systems (hydra and nematodes), it is particularly frequent in organisms with a highly developed central nervous system (primates, especially humans). Diversification of RNA transcript sequences via A-to-I editing serves a number of different functional roles, such as altering the genome-templated identity of particular amino acids in proteins or altering splice site junctions and modulating regulation of alternatively spliced mRNA variants. Here we provide an overview of current computational and experimental methods for the high-throughput discovery of edited RNA nucleotides in the human transcriptome, as well as a survey of the existing RNA editing bioinformatics resources and an outlook of future perspectives. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the physicochemical and sensory properties of oral nutritional supplements (ONSs). High physical stability was measured in ONSs with mean particle sizes <0.33 !m and viscosity >19.3 mPa·s. ONSs formulated with dairy-soy protein mixtures displayed low friction coefficients, whereas ONSs containing dairy proteins alone had high friction coefficient values in the boundary regime. Sensory analysis revealed low to medium liking across the products and the highest preference was found in samples with the highest perceived 'sweetness', 'vanilla aroma' and 'thickness'. The results will underpin the formulation of novel ONSs with good physical stability and sensory acceptability. [ABSTRACT FROM AUTHOR]

Background The implementation of MALDI-TOF MS for microorganism identification has changed the routine of the microbiology laboratories as we knew it. Most microorganisms can now be reliably identified within minutes using this inexpensive, user-friendly methodology. However, its application in the identification of mycobacteria isolates has been hampered by the structure of their cell wall. Improvements in the sample processing method and in the available database have proved key factors for the rapid and reliable identification of non-tuberculous mycobacteria isolates using MALDI-TOF MS. Aims The main objective is to provide information about the proceedings for the identification of non-tuberculous isolates using MALDI-TOF MS and to review different sample processing methods, available databases, and the interpretation of the results. Sources Results from relevant studies on the use of the available MALDI-TOF MS instruments, the implementation of innovative sample processing methods, or the implementation of improved databases are discussed. Content Insight about the methodology required for reliable identification of non-tuberculous mycobacteria and its implementation in the microbiology laboratory routine is provided. Implications Microbiology laboratories where MALDI-TOF MS is available can benefit from its capacity to identify most clinically interesting non-tuberculous mycobacteria in a rapid, reliable, and inexpensive manner. [ABSTRACT FROM AUTHOR]

In this research we demonstrate that a flexible ultra-thin supercapacitor can be fabricated using high volume screen printing process. This has enabled the sequential deposition of current collector, electrode, electrolyte materials and adhesive onto a Polyethylene terephthalate (PET) substrate in order to form flexible electrodes for reliable energy storage applications. The electrodes were based on an activated carbon ink and gel electrolyte each of which were formulated for this application. Supercapacitors that have surface areas from 100 to 1600 mm 2 and an assembled device thickness of 375 μm were demonstrated. The capacitance ranged from 50 to 400 mF. Capacitance of printed carbon electrodes is rarely reported in literature and no references were found. The chemistry developed during this study displayed long-term cycling potential and demonstrated the stability of the capacitor for continued usage. The gel electrolyte developed within this work showed comparable performance to that of a liquid counterpart. This improvement resulted in the reduction in gel resistance from 90Ω to 0.5Ω. Significant reduction was observed for all resistances. The solid-state supercapacitors with the gel electrolyte showed comparable performance to the supercapacitors that used a liquid electrolyte. This large area printed device can be used in future houses for reliable green energy storage. [ABSTRACT FROM AUTHOR]

This research has demonstrated how an ultra-thin rechargeable battery technology has been fabricated using screen printing technology. The screen printing process enabled the sequential deposition of current collector, electrode and separator/electrolyte materials onto a polyethylene terephthalate (PET) substrate in order to form both flexible and rechargeable electrodes for a battery application. The anode and cathode fabricated were based on the conducting poly (3,4-ethylenedioxythiophen): poly (styrene sulfonate) (PEDOT: PSS) and polyethyleneimine (PEI) which were combined to form the electrodes. The difference in the oxidation level between the two electrodes produced an open circuit voltage of 0.60 V and displayed a practical specific capacity of 5.5 mAh g −1 . The battery developed had an active surface area of 400 mm 2 and a device thickness of 440 μm. The chemistry developed during this study displayed long-term cycling potential and proves the stability of the cells for continued usage. This technology has direct uses in future personal wearable electronic devices. [ABSTRACT FROM AUTHOR]

Aims: To develop an efficient purification strategy for the bacteriophage lysin CHAPK. To evaluate its antibacterial spectrum, enzymatic properties, optimal reaction conditions and lytic activity against live Staphlyococcus aureus. Methods and Results: Recombinant CHAPK was purified to homogeneity by cation exchange chromatography, with yields of up to 10 mg from 1 l of Escherichia coli culture. The lytic spectrum of CHAPK includes all staphylococcal species and also members of the genera Micrcococcus, Streptococcus, Nesterenkonia, Arthrobacter, Leuconostoc and Carnobacterium. The enzyme was active from pH 6 to 11 with an optimum activity at pH 9, from 5 to 40°C, with an optimum activity at 15°C. When cell lysis by CHAPK and lysostaphin was compared over a concentration range of 2·5-10 μg ml−1 using live Staph. aureus for 5 min at 37°C, CHAPK gave rise to greater turbidity reduction indicating that it works more rapidly than lysostaphin. Conclusions: This study describes in detail the purification and characteristics of the novel phage-derived enzyme CHAPK demonstrating that it has excellent biochemical properties as an anti-staphylococcal agent. Significance and Impact of the Study: Currently, there is a need for new antimicrobial agents due to the increasing worldwide prevalence of antibiotic resistance. Our findings demonstrate the potential for development of CHAPK as an alternative therapeutic against pathogenic staphylococci including MRSA. [ABSTRACT FROM AUTHOR]

In response to consumer demands, plant protein ingredients are increasingly being used in the formulation of plant-based alternatives to cheese. The aim of this study was to determine the influence of protein concentration on key quality attributes of chickpea-based alternatives to cheese. Moreover, the age-induced changes in such attributes were assessed, with samples analysed after 1 month of storage. After characterisation of the ingredients, the chickpea-based formulations were prepared by blending chickpea flour and protein concentrate in different proportions to obtain four samples of increasing protein content (i.e., 8.68-21.5%). Formulations were developed at pH ∼4.5, and a moisture content of 50%, with shea butter used to obtain 15% fat content. The differential scanning calorimetry thermograms of the samples showed a main peak around 30 °C, corresponding to transition of the shea butter, and a smaller peak around 70 °C related to starch gelatinisation. Analysis of microstructure showed formation of a protein matrix with more extensive protein structure at high protein concentration. Furthermore, none of the chickpea-based samples melted under the testing conditions and all samples showed increasing values for adhesiveness, springiness and cohesiveness with increasing protein content. However, hardness was the highest for the sample with the lowest protein content, likely due to starch retrogradation. After storage, hardness increased further for all samples. This work improves our understanding of the role of chickpea protein in developing plant-based alternatives to cheese and the challenges therein., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s).)