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Enzymes derived from microbial sources have gained increasing popularity in industrial applications over the past decades. Despite the high production cost, alkaline proteases have wide applications in industries such as tanneries, food production, and detergents. In recent years, there has been a shift towards utilizing natural carbon sources for cultivating microorganisms and extracting proteases in order to reduce production costs. This study aimed to investigate the biochemical and kinetic properties of protease enzymes obtained from Aspergillus niger cultivated in a paper waste medium and compare with the enzyme produced in a basal medium. Glucose is a more favorable carbon source compared to cellulose, so paper waste was pretreated with cellulose-degrading bacteria to convert cellulose into smaller carbohydrates. After the growth of A. niger in basal and combinational media, the enzymatic properties were compared between the extracted enzymes by using casein as substrate. The results demonstrated that A. niger could produce protease enzymes in the paper waste medium similar to the basal medium with more than 5-fold cost saving. The specific activity of the enzymes isolated from the basal and paper waste media was calculated to be 184.95 ± 10.56 U ml−1 and 169.88 ± 11.05 U ml−1, respectively. Carbon sources did not affect the optimum pH and temperature of the protease enzyme, which were found to be 8 and 37 °C, respectively. This study provides valuable insights into the production of alkaline protease from A. niger using a combinational medium (paper waste pretreated by cellulose-degrading bacteria), offering a cost-effective approach for industrial applications. [ABSTRACT FROM AUTHOR]

Phosphates and citrates are calcium sequestering salts (CSS) most commonly used in the manufacture of processed cheese, either singly or in mixtures. Caseins are the main structure forming elements in processed cheese. Calcium sequestering salts decrease the concentration of free calcium ions by sequestering calcium from the aqueous phase and dissociates the casein micelles into small clusters by altering the calcium equilibrium, thereby resulting in enhanced hydration and voluminosity of the micelles. Several researchers have studied milk protein systems such as rennet casein, milk protein concentrate, skim milk powder, and micellar casein concentrate to elucidate the influence of calcium sequestering salts on (para-)casein micelles. This review paper provides an overview of the effects of calcium sequestering salts on the properties of casein micelles and consequently the physico-chemical, textural, functional, and sensorial attributes of processed cheese. A lack of proper understanding of the mechanisms underlying the action of calcium sequestering salts on the processed cheese characteristics increases the risk of failed production, leading to the waste of resources and unacceptable sensorial, appearance, and textural attributes, which adversely affect the financial side of processors and customer expectations. [ABSTRACT FROM AUTHOR]

For over 20 years, bovine beta-casein has been a subject of increasing scientific interest because its genetic A1 variant during gastrointestinal digestion releases opioid-like peptide β-casomorphin-7 (β-CM-7). Since β-CM-7 is involved in the dysregulation of many physiological processes, there is a growing discussion of whether the consumption of the β-casein A1 variant has an influence on human health. In the last decade, the number of papers dealing with this problem has substantially increased. The newest clinical studies on humans showed a negative effect of variant A1 on serum glutathione level, digestive well-being, cognitive performance score in children, and mood score in women. Scientific reports in this field can affect the policies of dairy cattle breeders and the milk industry, leading to the elimination of allele A1 in dairy cattle populations and promoting milk products based on milk from cows with the A2A2 genotype. More scientific proof, especially in well-designed clinical studies, is necessary to determine whether a little difference in the β-casein amino acid sequence negatively affects the health of milk consumers. [ABSTRACT FROM AUTHOR]

Kupres cheese is a traditional Bosnian full-fat hard cheese. This paper deals with the change of protein and fatty acid profiles, mineral content and antioxidant potential during the period of three months of its ripening. Proteolysis was monitored by the electrophoresis of total extracts and water-soluble fractions under reducing conditions, whereas fatty acid profiles were determined by gas chromatography. The mineral content in the ripened cheeses was determined by using methods of Inductively coupled plasma - optical emission spectrometry (ICP-OES) for microelements and Inductively coupled plasma mass spectrometry (ICP-MS) for microelements, respectively. Ripening of Kupres cheese during three months is characterised by a relatively slow proteolysis, especially during the first month and by the increase in desirable fatty acid content. After 30 days of ripening, the WSN/TN and TCA/TN contents increased from 8.23 % and 2.25 % to 10.15 % and 3.59 %, respectively. Further, ripening induced higher increase of these parameters and more intensive degradation of the major caseins, especially αs-CN. After three months of ripening, residual level of αs-CN and β-CN was 12.02 % and 80.96 %, respectively. Three month-old cheese had improved indexes of lipid quality as well as improved reducing power and ability to scavenge free radicals. Ripening affected the content of Ca, P and Na whereas no significant changes of the other macroand microelements of Kupres cheese were observed. [ABSTRACT FROM AUTHOR]

The study of polymorphism of beta-casein genes CSN2 and kappa-casein CSN3 in cows of Brown cattle, Simmental breed, Black and White cattle has been carried out with the use of polymerase chain reaction in real time. It is shown that the frequency distribution of CSN2 / CSN3 composite genotypes differs significantly in different breeds: Brown cattle - 22.0 А1А2/AB, 22.7% А2А2/AB and 22.0% А2А2/BB; Simmental - 26.8% А1А2/AB; А2А2/AF, 22.0%, А2А2/AB 19.5%; Black and White cattle - 26.9% А1А2/AA; А1А1/AB, 23.1%, А2А2/AA 23.1%. The obtained results indicate the prospects of breeding work concerning the formation of herds (micropopulations) by the A2A2/BB composite genotype, which is only possible among Brown breeds. This makes it possible to increase the effectiveness of measures to preserve the population of Brown cattle by improving the quality of their milk. [ABSTRACT FROM AUTHOR]

This paper aimed to explore the antioxidant activity of A1 and A2 casein hydrolysates and compare their effectiveness. Enzymatic hydrolysis of casein produces bioactive peptides that offer various health benefits, including antioxidant, antihypertensive, antidiabetic, antithrombotic, and immunomodulatory properties. In this study, A1 and A2 casein were hydrolyzed using trypsin at different time intervals (2, 4, and 6 h). The degree of hydrolysis (DH) was determined to assess the extent of peptide bond cleavage during proteolysis. The hydrolysates were then evaluated for their radical scavenging potential using DPPH and ABTS assays, as well as their reducing power. The results indicate that both A1 and A2 casein can be effectively hydrolyzed with trypsin, with 6 h of hydrolysis found to be optimal in terms of DH and scavenger activity. Both A1 and A2 casein hydrolysates demonstrated antioxidant activity against DPPH radical and ABTS radical cation. However, at a high concentration (5% casein), A2 hydrolysate exhibited significantly higher antioxidant activity compared to A1. These findings offer insights into the potential use of A1 and A2 casein hydrolysates as natural antioxidants in functional foods and nutraceuticals, providing a safer and more sustainable alternative to synthetic antioxidants. • Enzymatic hydrolysis of casein produces bioactive peptides. • The optimal duration for trypsin hydrolysis was found to be 6 h. • A1 and A2 casein hydrolysates revealed potential as natural antioxidants in foods. [ABSTRACT FROM AUTHOR]

The authors investigated the possibility of using modern biotechnological methods for obtaining in vitro embryos from females of the local breed with the desired complex genotype by the A2A2/BB beta- and kappa-casein, cryopreservation and long-term storage in the system of preserving the gene pool. During the first stage of work, 27 oocytes-cumulus complexes (OCCs) were obtained from the ovaries of heifers, of which 66.7% were selected as suitable for in vitro cultivation, and from the ovaries of cows - 69.2% of oocytes-cumulus complexes (45 of the 65 obtained oocytes-cumulus complexes) were suitable for further cultivation. Our cytogenetic analysis of heifer egg cells showed that 33.3% (9 out of 27 cultured oocytes-cumulus complexes) of cells were at the metaphase II stage of meiosis, and 66.7% had chromosomal disorders. The second stage involved the fertilization of egg cells matured outside the body. During this stage, it was found that the level of zygote formation on average reached 23.8%, and further cultivation also provided in vitro fragmentation of embryos at the level of 22.2% (10 embryos from 63 inseminated eggs). It was found that the overall level of embryo formation after fertilization of egg cells of cows matured outside the body was 33.3%. For the conservation and rational use of breeding (genetic) resources of cattle at the cellular level, it is necessary to create cryobanks of gametes for long-term storage in order to further sell them for reproduction. [ABSTRACT FROM AUTHOR]

Bovine mastitis is considered the leading cause of economic losses in dairy farms worldwide due to the associated treatment costs, reduced cow performance, milk quantity, and quality decline, as well as early culling. The purpose of this study was to examine the relationship between somatic cell count (SCC), and physicochemical milk parameters in Romanian Black and White spotted dairy cows. In the study conducted between March and September of 2022, on a farm from the Northeast Romania, a total of 62 cows, with ages ranging from 3 to 5 years, average days in milk (DIM) 75 +/- 35 days, and milk production 22+/- 1.8 kg (mean +/- SEM and clinical signs of mastitis were enrolled. Cows were clinically examined and milk samples were collected in order to evaluate milk SCC and physicochemical parameters such as fat, protein, lactose, casein, dry matter percentage, and density using the fluorooptic method (Combiscope, Delta Instruments). Statistical analysis was carried out using Graphpad Prism software. A correlation matrix was computed to establish the relationship between the number of somatic cells, and the physicochemical parameters of milk. A very small significant negative relationship was observed between somatic cell score and lactose percentage (r= -0.56), as well as milk fat (r= -0.39) and protein (r= -0.37). In conclusion, bovine mastitis has a negative impact on both milk production and composition, however further studies involving both healthy and cows with mastitis are needed for a more robust evaluation of clinical mastitis effect on milk parameters. [ABSTRACT FROM AUTHOR]

Genotyping of 47 stud bulls of Brown breeds was carried out by the gene CSN3. The results of scientific studies indicate that both Brown purebred and cross-breed cattle bred in Ukraine are characterized by a significant difference in the frequency of genotypes by this trait. The genetic equilibrium established by us corresponds to the global trends of breed populations. The creation of the desired micro-populations with the desired homozygous BB genotype by kappa-casein makes it possible to improve the quality of milk as a raw material for milk processing enterprises specialized in cheese making. Therefore, the increased frequency of the BB genotype by kappa-casein may contribute to the preservation and distribution of Brown cattle in Ukrainian farms. [ABSTRACT FROM AUTHOR]

Researches were carried out on 1707 Romanian Spotted cows raised in farms from Hunedoara County that were enrolled in official performance control scheme. According to the number of milking cows (farm size), farms were divided into three categories small (n≤10 cows), middle (n=11 to 25 cows) and large (n>25 cows). The influence of the farm size on the daily milk yield and milk components (fat, protein, casein and lactose) was determined by using ANOVA, and lactation curve was drawn using the gamma incomplete function. Generally, the farm size had a significant influence on all studied milk indices (p<0.01). For the daily milk yield and fat percentage, the highest values were obtained in the small farms (25.50 kg milk with 3.82% fat), followed by the large farms (23.45 kg milk with 3.76% fat) and the middle farms (21.46 kg with 3.69% fat). For protein percentage and casein content, the highest values were obtained in middle farms (3.32% protein and 25.66 g/L casein) followed by small farms (3.27% protein and 25.41 g/L casein) and large farms (3.25% protein and 25.58 g/L casein). The highest values for milk lactose percentage were obtained in large farms (4.81%) followed by middle and small farms (4.78% and 4.76%, respectively). In conclusion, we can state that the farm size had an influence on daily milk yield and its chemical components, due to feeding and housing technologies employed in those farms. Small farms had the highest daily milk yield and fat percentage, middle farms' milk was higher in protein and casein content, while large farms had the highest lactose percentage in the milk. [ABSTRACT FROM AUTHOR]

Summary: Proteases are theprotein degrading commercial enzymes with considerable importance for many industrial applications such as paper, leather, food industries as well as used in detergent formulation, toxic waste removal, pharmaceutical and drilling for oil. The focus of the current study was to isolate the novel protease producing bacterial sp. from environment, to optimize the submerged fermentation parameters in order to design the best supportive media for maximum enzyme yield and to purify the enzyme to increase its utilization in various industries, most importantly the pharmaceutical industry.Five pure cultures were isolated from soil of coastal area, Karachi and the bacterial strain that was proved to be the most potent producer of protease was selected for research purposeand named as Bacillus sp AI-5 after series of morphological and biochemical tests. The fermentation conditions and media composition were optimized using the starter medium that was selected among the three previously reported media for protease production. It was found that protease production from Bacillus sp AI-5 reached to maximum when media was supplemented with 0.4 gm% casein as carbon source, the combination of 0.5 gm% yeast extract and 0.5 gm% peptone as nitrogen source and 0.05 gm CaCl2 as inducer and stabilizer of proteases. The optimum pH and temperature for maximum production of protease were found to be pH 5 a nd 45 °C respectively after 24 hours of incubation. The protease of the Bacillus sp. AI-5 was purified to homogeneity by salt fractionation method using 60 gm% ammonium sulfate, dialysis and Sephadex G-100 Gel filtration chromatography. The specific activity of purified protease was found to be 322.25 U/mg with 13.80 fold purification as compared to crude enzyme. The purified enzyme gave a single band on Sodiumdodecyl sulfate Polyacrylamide gel electrophoresis (SDS-PAGE)corresponding to a molecular weight of 66 kDa. [ABSTRACT FROM AUTHOR]