Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 12.108
Filter
1.
Microb Cell Fact ; 23(1): 263, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39367390

ABSTRACT

BACKGROUND: The ß-galactosidase from Paenibacillus wynnii (ß-gal-Pw) is a promising candidate for lactose hydrolysis in milk and dairy products, as it has a higher affinity for the substrate lactose (low KM value) compared to industrially used ß-galactosidases and is not inhibited by the hydrolysis-generated product D-galactose. However, ß-gal-Pw must firstly be produced cost-effectively for any potential industrial application. Accordingly, the yeast Komagataella phaffii was chosen to investigate its feasibility to recombinantly produce ß-gal-Pw since it is approved for the regulated production of food enzymes. The aim of this study was to find the most suitable way to produce the ß-gal-Pw in K. phaffii either extracellularly or intracellularly. RESULTS: Firstly, 11 different signal peptides were tested for extracellular production of ß-gal-Pw by K. phaffii under the control of the constitutive GAP promoter. None of the signal peptides resulted in a secretion of ß-gal-Pw, indicating problems within the secretory pathway of this enzyme. Therefore, intracellular ß-gal-Pw production was investigated using the GAP or methanol-inducible AOX1 promoter. A four-fold higher volumetric ß-galactosidase activity of 7537 ± 66 µkatoNPGal/Lculture was achieved by the K. phaffii clone 27 using the AOX1 promoter in fed-batch bioreactor cultivations, compared to the clone 5 using the GAP promoter. However, a two-fold higher specific productivity of 3.14 ± 0.05 µkatoNPGal/gDCW/h was achieved when using the GAP promoter for ß-gal-Pw production compared to the AOX1 promoter. After partial purification, a ß-gal-Pw enzyme preparation with a total ß-galactosidase activity of 3082 ± 98 µkatoNPGal was obtained from 1 L of recombinant K. phaffii culture (using AOX1 promoter). CONCLUSION: This study showed that the ß-gal-Pw was produced intracellularly by K. phaffii, but the secretion was not achieved with the signal peptides chosen. Nevertheless, a straightforward approach to improve the intracellular ß-gal-Pw production with K. phaffii by using either the GAP or AOX1 promoter in bioreactor cultivations was demonstrated, offering insights into alternative production methods for this enzyme.


Subject(s)
Paenibacillus , Recombinant Proteins , Saccharomycetales , beta-Galactosidase , beta-Galactosidase/metabolism , beta-Galactosidase/genetics , Paenibacillus/enzymology , Paenibacillus/genetics , Saccharomycetales/genetics , Saccharomycetales/metabolism , Saccharomycetales/enzymology , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Recombinant Proteins/biosynthesis , Lactose/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism
2.
Nat Commun ; 15(1): 7735, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39232002

ABSTRACT

Breastfeeding provides many health benefits, but its impact on respiratory health remains unclear. This study addresses the complex and dynamic nature of the mother-milk-infant triad by investigating maternal genomic factors regulating human milk oligosaccharides (HMOs), and their associations with respiratory health among human milk-fed infants. Nineteen HMOs are quantified from 980 mothers of the CHILD Cohort Study. Genome-wide association studies identify HMO-associated loci on chromosome 19p13.3 and 19q13.33 (lowest P = 2.4e-118), spanning several fucosyltransferase (FUT) genes. We identify novel associations on chromosome 3q27.3 for 6'-sialyllactose (P = 2.2e-9) in the sialyltransferase (ST6GAL1) gene. These, plus additional associations on chromosomes 7q21.32, 7q31.32 and 13q33.3, are replicated in the independent INSPIRE Cohort. Moreover, gene-environment interaction analyses suggest that fucosylated HMOs may modulate overall risk of recurrent wheeze among preschoolers with variable genetic risk scores (P < 0.01). Thus, we report novel genetic factors associated with HMOs, some of which may protect the respiratory health of children.


Subject(s)
Genome-Wide Association Study , Milk, Human , Oligosaccharides , Sialyltransferases , Humans , Milk, Human/chemistry , Milk, Human/metabolism , Female , Oligosaccharides/metabolism , Sialyltransferases/genetics , Sialyltransferases/metabolism , Infant , Male , Child, Preschool , Fucosyltransferases/genetics , Breast Feeding , Respiratory Sounds/genetics , Gene-Environment Interaction , Polymorphism, Single Nucleotide , Adult , Cohort Studies , Mothers , Child , Chromosomes, Human, Pair 3/genetics , Lactose/analogs & derivatives
3.
Nat Commun ; 15(1): 7976, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39266519

ABSTRACT

Cellular homeostasis depends on the supply of metabolic energy in the form of ATP and electrochemical ion gradients. The construction of synthetic cells requires a constant supply of energy to drive membrane transport and metabolism. Here, we provide synthetic cells with long-lasting metabolic energy in the form of an electrochemical proton gradient. Leveraging the L-malate decarboxylation pathway we generate a stable proton gradient and electrical potential in lipid vesicles by electrogenic L-malate/L-lactate exchange coupled to L-malate decarboxylation. By co-reconstitution with the transporters GltP and LacY, the synthetic cells maintain accumulation of L-glutamate and lactose over periods of hours, mimicking nutrient feeding in living cells. We couple the accumulation of lactose to a metabolic network for the generation of intermediates of the glycolytic and pentose phosphate pathways. This study underscores the potential of harnessing a proton motive force via a simple metabolic network, paving the way for the development of more complex synthetic systems.


Subject(s)
Malates , Decarboxylation , Malates/metabolism , Glutamic Acid/metabolism , Biological Transport , Artificial Cells/metabolism , Lactic Acid/metabolism , Lactose/metabolism , Escherichia coli/metabolism , Nutrients/metabolism , Proton-Motive Force , Antiporters/metabolism , Glycolysis , Metabolic Networks and Pathways , Protons , Pentose Phosphate Pathway
4.
World J Microbiol Biotechnol ; 40(10): 324, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39294482

ABSTRACT

High fidelity DNA polymerase from Pyrococcus furiosus (Pfupol) is an attractive alternative to the highly popular DNA polymerase from Thermus aquaticus. Because this enzyme is in great demand for biotechnological applications, optimizing Pfupol production is essential to supplying the industry's expanding demand. T7-induced promoter expression in Escherichia coli expression systems is used to express recombinant Pfupol; however, this method is not cost-effective. Here, we have effectively developed an optimized process for the autoinduction approach of Pfupol expression in a defined medium. To better examine Pfupol's activities, its purified fraction was used. A 71 mg/L of pure Pfupol was effectively produced, resulting in a 2.6-fold increase in protein yield when glucose, glycerol, and lactose were added in a defined medium at concentrations of 0.05%, 1%, and 0.6%, respectively, and the condition for production in a 5 L bioreactor was as follow: 200 rpm, 3 vvm, and 10% inoculant. Furthermore, the protein exhibited 1445 U/mg of specific activity when synthesized in its active state. This work presents a high level of Pfupol production, which makes it an economically viable and practically useful approach.


Subject(s)
Bioreactors , Culture Media , DNA-Directed DNA Polymerase , Escherichia coli , Pyrococcus furiosus , Recombinant Proteins , Pyrococcus furiosus/genetics , Pyrococcus furiosus/enzymology , Escherichia coli/genetics , Escherichia coli/metabolism , Bioreactors/microbiology , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , DNA-Directed DNA Polymerase/metabolism , DNA-Directed DNA Polymerase/genetics , Culture Media/chemistry , Glucose/metabolism , Promoter Regions, Genetic , Glycerol/metabolism , Lactose/metabolism
5.
Carbohydr Polym ; 345: 122543, 2024 Dec 01.
Article in English | MEDLINE | ID: mdl-39227090

ABSTRACT

Lacto-N-neotetraose (LNnT), as a neutral core structure within human milk oligosaccharides (HMOs), has garnered widespread attention due to its exceptional physiological functions. In the process of LNnT synthesis using cellular factory approaches, substrate promiscuity of glycosyltransferases leads to the production of longer oligosaccharide derivatives. Here, rational modification of ß1,3-N-acetylglucosaminyltransferase from Neisseria meningitidis (LgtA) effectively decreased the concentration of long-chain LNnT derivatives. Specifically, the optimal ß1,4-galactosyltransferase (ß1,4-GalT) was selected from seven known candidates, enabling the efficient synthesis of LNnT in Escherichia coli BL21(DE3). Furthermore, the influence of lactose concentration on the distribution patterns of LNnT and its longer derivatives was investigated. The modification of LgtA was conducted with computational assistance, involving alanine scanning based on molecular docking to identify the substrate binding pocket and implementing large steric hindrance on crucial amino acids to obstruct LNnT entry. The implementation of saturation mutagenesis at positions 223 and 228 of LgtA yielded advantageous mutant variants that did not affect LNnT synthesis while significantly reducing the production of longer oligosaccharide derivatives. The most effective mutant, N223I, reduced the molar ratio of long derivatives by nearly 70 %, showcasing promising prospects for LNnT production with diminished byproducts.


Subject(s)
N-Acetylglucosaminyltransferases , Neisseria meningitidis , Oligosaccharides , Neisseria meningitidis/enzymology , N-Acetylglucosaminyltransferases/metabolism , N-Acetylglucosaminyltransferases/genetics , Oligosaccharides/chemistry , Oligosaccharides/chemical synthesis , Molecular Docking Simulation , Escherichia coli/genetics , Substrate Specificity , Lactose/analogs & derivatives , Lactose/metabolism , Lactose/chemistry , Humans
6.
Nutrients ; 16(17)2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39275273

ABSTRACT

6'-Sialyllactose (6'-SL), found in human breast milk, exhibits anti-inflammatory, immune function-enhancing, brain development-promoting, and gut health-improving effects. However, its effects on muscle fatigue remain unknown. Here, we aimed to investigate the effects of 6'-SL on blood lactate level, muscle fiber type, and oxidative phosphorylation protein complexes (OXPHOS) in muscle after exercise using C57BL/6J male mice. C57BL/6J mice were randomly assigned to control or 100 mg/kg 6'-SL. After 12 weeks of 6'-SL administration, the mice were made to perform treadmill exercise; their blood lactate and glucose levels were measured at the basal level (rest) and 0, 5, and 10 min after treadmill exercise. Results showed that 6'-SL treatment in C57BL/6J mice significantly reduced blood lactate level and improved blood glucose level. Moreover, 6'-SL increased the expression of slow-myosin heavy chain (MHC) and OXPHOS in gastrocnemius muscle. In addition, 6'-SL treatment for 12 weeks did not affect food intake, serum biomarkers of tissue injury, and lipid profiles compared with those of the controls. These findings indicate that non-toxic 6'-SL suppressed muscle fatigue during exercise by promoting protein expression of muscle fibers, especially slow-twitch muscle fibers characterized by abundant OXPHOS complexes and decreased blood lactate level. This study suggests that 6'-SL holds promise as a nutritional supplement in exercise and clinical settings, subject to further validation.


Subject(s)
Lactic Acid , Mice, Inbred C57BL , Muscle Fatigue , Muscle, Skeletal , Physical Conditioning, Animal , Animals , Male , Lactic Acid/blood , Mice , Muscle Fatigue/drug effects , Muscle, Skeletal/metabolism , Muscle, Skeletal/drug effects , Lactose/analogs & derivatives , Lactose/pharmacology , Blood Glucose/metabolism , Blood Glucose/drug effects
7.
Sci Rep ; 14(1): 20827, 2024 09 06.
Article in English | MEDLINE | ID: mdl-39242646

ABSTRACT

Understanding the human milk metabolome can help inform infant nutrition and health. Untargeted metabolomics was used to study breast milk from 31 healthy participants to assess the shared metabolites in milk from participants with various backgrounds and understand how different demographic, health, and environmental factors impact the milk metabolome. Breast milk samples were analyzed by four separate UPLC-MS/MS methods. Metabolite Set Enrichment Analysis was used to study the most and least variable metabolites. The associations between participant factors and the metabolome were assessed with redundancy analyses. Among all 31 participants and between each untargeted UPLC-MS/MS method, 731 metabolites were detected, of which 389 were shared among all participants. Of the shared metabolites, lactose was the least and lactobionate the most variable metabolite. In the biological super pathway analysis, xenobiotics were the most variable metabolites. Infant age, maternal age, number of live births, and pre-pregnancy BMI were associated with the milk metabolome. In conclusion, the most variable metabolites originate from environmental exposures while the well-conserved core metabolites are linked to cell metabolism or are crucial for infant nutrition and osmoregulation. Understanding the variability of the breast milk metabolome can help identify components that are crucial for infant nutrition, growth, and development.


Subject(s)
Metabolome , Metabolomics , Milk, Human , Humans , Milk, Human/metabolism , Milk, Human/chemistry , Female , Metabolomics/methods , Adult , Mothers , Tandem Mass Spectrometry , Infant , Young Adult , Lactose/metabolism , Lactose/analysis
8.
Sheng Wu Gong Cheng Xue Bao ; 40(9): 2846-2865, 2024 Sep 25.
Article in Chinese | MEDLINE | ID: mdl-39319711

ABSTRACT

Human milk oligosaccharides (HMOs) are a structurally complex group of unbound polysaccharides, representing the third-largest solid component in breast milk. They play a crucial role in the intestinal health and immune system development of infants. Sialylated HMOs, including 3'-sialactose (3'-SL) and 6'-sialactose (6'-SL), are major components of HMOs, playing significant roles in immune regulation, anti-inflammatory processes, and promotion of probiotic growth. Currently, the cost-effective production of high-value sialactose by microbial fermentation with readily available raw materials has become a research hotspot due to the high nutritional value and potential applications of sialylated HMOs in infant food. This paper summarizes the functions and biosynthesis of 3'-SL and 6'-SL. Furthermore, it reviews the research progress in the synthesis of sialactose by Escherichia coli, offering valuable insights for future industrial production.


Subject(s)
Escherichia coli , Milk, Human , Oligosaccharides , Escherichia coli/metabolism , Oligosaccharides/biosynthesis , Humans , Lactose/metabolism , Lactose/analogs & derivatives , Fermentation
9.
Viruses ; 16(9)2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39339927

ABSTRACT

The recent incursion of highly pathogenic influenza viruses into dairy cattle opens new insights for influenza virus ecology and its interspecies transmission and may have a significant impact on public health and agriculture. The aim of this study was to determine the stability of a bovine highly pathogenic avian influenza H5N1 virus isolate in the milk byproduct lactose and to evaluate two inactivation methods using industrial procedures. The bovine isolate of the highly pathogenic avian influenza H5N1 virus was stable for 14 days in a concentrated lactose solution under refrigerated conditions. Heat or citric acid treatments successfully inactivated the virus in lactose. This study highlights the persistence of HPAIV in lactose and its efficient inactivation under industrial standards.


Subject(s)
Influenza A Virus, H5N1 Subtype , Lactose , Milk , Virus Inactivation , Lactose/pharmacology , Animals , Cattle , Milk/virology , Influenza A Virus, H5N1 Subtype/drug effects , Hot Temperature , Citric Acid/pharmacology
10.
Glycobiology ; 34(9)2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39115362

ABSTRACT

α -Lactalbumin, an abundant protein present in the milk of most mammals, is associated with biological, nutritional and technological functionality. Its sequence presents N-glycosylation motifs, the occupancy of which is species-specific, ranging from no to full occupancy. Here, we investigated the N-glycosylation of bovine α-lactalbumin in colostrum and milk sampled from four individual cows, each at 9 time points starting from the day of calving up to 28.0 d post-partum. Using a glycopeptide-centric mass spectrometry-based glycoproteomics approach, we identified N-glycosylation at both Asn residues found in the canonical Asn-Xxx-Ser/Thr motif, i.e. Asn45 and Asn74 of the secreted protein. We found similar glycan profiles in all four cows, with partial site occupancies, averaging at 35% and 4% for Asn45 and Asn74, respectively. No substantial changes in occupancy occurred over lactation at either site. Fucosylation, sialylation, primarily with N-acetylneuraminic acid (Neu5Ac), and a high ratio of N,N'-diacetyllactosamine (LacdiNAc)/N-acetyllactosamine (LacNAc) motifs were characteristic features of the identified N-glycans. While no substantial changes occurred in site occupancy at either site during lactation, the glycoproteoform (i.e. glycosylated form of the protein) profile revealed dynamic changes; the maturation of the α-lactalbumin glycoproteoform repertoire from colostrum to mature milk was marked by substantial increases in neutral glycans and the number of LacNAc motifs per glycan, at the expense of LacdiNAc motifs. While the implications of α-lactalbumin N-glycosylation on functionality are still unclear, we speculate that N-glycosylation at Asn74 results in a structurally and functionally different protein, due to competition with the formation of its two intra-molecular disulphide bridges.


Subject(s)
Colostrum , Lactalbumin , Milk , Lactalbumin/metabolism , Lactalbumin/chemistry , Animals , Glycosylation , Colostrum/chemistry , Colostrum/metabolism , Cattle , Milk/chemistry , Milk/metabolism , Female , Lactation/metabolism , Amino Sugars/chemistry , Amino Sugars/metabolism , Glycopeptides/metabolism , Glycopeptides/chemistry , Glycopeptides/analysis , Lactose/metabolism , Lactose/chemistry
11.
Nat Microbiol ; 9(10): 2696-2709, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39160293

ABSTRACT

Resource competition is a driver of gut microbiota composition. Bacteria can outcompete metabolically similar rivals through the limitation of shared growth-fuelling nutrients. The mechanisms underlying this remain unclear for bacteria with identical sets of metabolic genes. Here we analysed the lactose utilization operon in the murine commensal Escherichia coli 8178. Using in vitro and in vivo approaches, we showed that translation of the lactose utilization repressor gene lacI from its native non-canonical GTG start codon increases the basal expression of the lactose utilization cluster, enhancing adaptation to lactose consumption. Consequently, a strain carrying the wild type lacI GTG start codon outperformed the lacI ATG start codon mutant in the mouse intestine. This advantage was attenuated upon limiting host lactose intake through diet shift or altering the mutant frequency, emphasizing the context-dependent effect of a single nucleotide change on the bacterial fitness of a common member of the gut microbiota. Coupled with a genomic analysis highlighting the selection of non-ATG start codons in sugar utilization regulator genes across the Enterobacteriaceae family, our data exposed an unsuspected function of non-canonical start codons in metabolic competition.


Subject(s)
Codon, Initiator , Escherichia coli , Gastrointestinal Microbiome , Lactose , Animals , Mice , Escherichia coli/genetics , Escherichia coli/metabolism , Gastrointestinal Microbiome/genetics , Codon, Initiator/genetics , Lactose/metabolism , Gene Expression Regulation, Bacterial , Lac Repressors/genetics , Lac Repressors/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Carbohydrate Metabolism/genetics , Symbiosis , Operon , Lac Operon/genetics , Mice, Inbred C57BL
12.
Immunology ; 173(3): 562-574, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39108003

ABSTRACT

Group 2 innate lymphoid cells (ILC2s) play a crucial role in the progression of asthma, yet the regulatory mechanisms modulating ILC2 responses in asthma remain underexplored. Human milk oligosaccharides (HMOs), vital non-nutritive components of breast milk, are known to significantly shape immune system development and influence the incidence of allergic diseases. However, their impact on ILC2-driven asthma is not fully understood. Our research reveals that dietary HMOs act as potent inhibitors of ILC2 responses and allergic airway inflammation. Treatment with 2'-fucosyllactose (2'-FL) and 6'-sialyllactose (6'-SL) significantly reduced ILC2-related airway inflammation induced by papain or Alternaria alternata in mice, evidenced by decreased eosinophil (EOS) infiltration and lower IL-5 and IL-13 levels in BALF. Notably, while ILC2 expresses HMO receptors, HMO did not act directly on ILC2 but potentially modulated their activity through alterations in gut microbiota derived SCFAs. HMO treatments alleviated airway inflammation in SCFA-dependent manners, with SCFA depletion or receptor blocking reversing these beneficial effects. This study reveals the potential of dietary HMOs in managing asthma through modulation of ILC2 activity and the gut-lung axis, proposing a new therapeutic avenue that utilises the immunomodulatory capacities of nutritional components to combat respiratory diseases.


Subject(s)
Asthma , Gastrointestinal Microbiome , Lymphocytes , Milk, Human , Oligosaccharides , Milk, Human/immunology , Milk, Human/metabolism , Animals , Humans , Mice , Lymphocytes/immunology , Lymphocytes/metabolism , Lymphocytes/drug effects , Asthma/immunology , Asthma/diet therapy , Asthma/drug therapy , Asthma/metabolism , Oligosaccharides/pharmacology , Gastrointestinal Microbiome/drug effects , Gastrointestinal Microbiome/immunology , Immunity, Innate/drug effects , Female , Trisaccharides/therapeutic use , Trisaccharides/pharmacology , Mice, Inbred BALB C , Lactose/analogs & derivatives , Lactose/metabolism , Cytokines/metabolism , Disease Models, Animal , Alternaria/immunology
13.
Int J Pharm ; 662: 124542, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39094919

ABSTRACT

This study investigates particle size segregation within the powder chamber of a vacuum drum-based capsule filling machine using various stirrer types and proposing novel designs to mitigate segregation. The stirrer is essential to the process, ensuring uniform density during volume-based filling. Three lactose grades, comprising 10% fine, 80% medium, and 10% coarse particles, were used, with tracer particles replacing fine or coarse particles, respectively. Dosages were collected over time for a line-array of five bores, and tracer concentrations were analysed using UV-Vis spectrophotometry. By visual assessments and stagnant zone observations particle segregation was evaluated and quantified by normalised tracer concentrations. Both standard and modified stirrers were examined under the same conditions. Stirrer type significantly influenced particle segregation, with the "spike" standard stirrer yielding the highest segregation, while the modified "3-wirem" and "coreless 3-wirem" stirrers exhibited superior performance, minimizing differences between fine and coarse particle concentrations and eliminating stagnant zones. These findings highlight promising prospects for further analysing the "3-wirem" and "coreless 3-wirem" stirrers. In that respect additional variables such as stirrer speed, rotation direction, and level of vacuum, need to be considered. Stirrer design significantly impacts vacuum drum-based capsule filling machine performance, ensuring reliable pharmaceutical capsule filling. This study offers insights into optimizing the industrial process.


Subject(s)
Capsules , Lactose , Particle Size , Powders , Vacuum , Lactose/chemistry , Powders/chemistry , Equipment Design , Drug Compounding/methods , Drug Compounding/instrumentation , Technology, Pharmaceutical/methods , Technology, Pharmaceutical/instrumentation , Excipients/chemistry
14.
Medicine (Baltimore) ; 103(31): e39098, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39093773

ABSTRACT

BACKGROUND: The aim of this study was to evaluate the efficacy and safety of formula milk powder in the treatment of lactose intolerance in children, and to provide an evidence-based medicine basis for the rational use of drugs in children with lactose intolerance caused by various reasons by meta-analysis. METHODS: Use computers to search major databases, including Web of Science, PubMed, CNKI, Wanfang Data Knowledge Service Platform, and other databases, the retrieval time is from the establishment of the database to April 2023. The collected literatures were screened, data extracted and processed, and then meta-analysis was performed by Review-Manager 5.4 statistical software. RESULTS: A total of 10 randomized controlled trials were included, with 1112 patients, including 562 patients in the treatment group and 550 patients in the control group. The control group was treated with conventional therapy, and the treatment group was treated with lactose-free/low-lactose milk powder on the basis of conventional therapy. The results of the meta-analysis showed that the clinical efficacy of the treatment group was significantly better than that of the control group [odds ratio=6.01, 95% confidence interval (CI): 3.94-9.18, P<0.00001], the course of disease in the treatment group was shorter than that in the control group (mean difference=-1.45, 95% CI: -1.76 to -1.13, P<0.0001). The antidiarrhea time of the treatment group was shorter than that of the control group, and the difference between the 2 groups was statistically significant (mean difference=-1.41, 95% CI: -1.67 to -1.15, P<0.0001). CONCLUSION: Low/lactose-free milk powder can improve clinical efficacy and shorten the course of treatment in infants with lactose intolerance, which can be demonstrated by further large-scale clinical studies.


Subject(s)
Lactose Intolerance , Meta-Analysis as Topic , Systematic Reviews as Topic , Humans , Lactose Intolerance/diet therapy , Infant , Infant Formula , Lactose , Milk , Randomized Controlled Trials as Topic , Powders , Treatment Outcome , Animals
15.
Int J Biol Macromol ; 277(Pt 3): 134202, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39089546

ABSTRACT

Cellobiose 2-epimerase (CE) catalyzes the conversion of the lactose into its high-value derivatives, epilactose and lactulose, which has great prospects in food applications. In this study, CE sequences from the Qinghai-Tibet Plateau gene catalogue, we screened these for structural flexibility through molecular dynamics simulation to identify potential psychrophilic CE candidates. One such psychrophilic CE we termed psyCE demonstrated exceptional epimerization activity, achieving an optimum activity of 122.2 ± 1.6 U/mg. Its kinetic parameters (Kcat and Km) for epimerization activity were 219.9 ± 5.6 s-1 and 261.9 ± 18.1 mM, respectively, representing the highest Kcat recorded among known cold-active CEs. Notably, this is the first report of a psychrophilic CE. The psyCE can effectively produce epilactose at 8 °C, converting 20.3 % of 200 mM lactose into epilactose within four hours. These findings suggest that psyCE is highly suitable for cryogenic food processing, and glaciers may serve as a valuable repository of psychrophilic enzymes.


Subject(s)
Carbohydrate Epimerases , Cellobiose , Carbohydrate Epimerases/genetics , Carbohydrate Epimerases/chemistry , Carbohydrate Epimerases/metabolism , Cellobiose/chemistry , Cellobiose/metabolism , Kinetics , Tibet , Molecular Dynamics Simulation , Lactose/metabolism , Lactose/chemistry , Amino Acid Sequence , Disaccharides
16.
Nutrients ; 16(16)2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39203737

ABSTRACT

Sialyllactose (SL) is a functional human milk oligosaccharide essential for immune support, brain development, intestinal maturation, and antiviral defense. However, despite its established health benefits, the effect of SL on exercise performance and muscle mass in mice remains unknown. Here, we aimed to investigate, for the first time, the effects of 6'-SL on muscle functions. Seven-week-old male C57BL/6J mice were administered 100 mg/kg 6'-SL for 12 weeks, after which exhaustive treadmill performance was conducted. Moreover, muscle strength was examined by grip strength, and muscle phenotype characteristics such as muscle mass, muscle fiber size, and muscle protein expression were also examined. The administration of 6'-SL significantly improved exhaustive treadmill performance metrics, including distance and exhaustion time. Grip strength was also increased by 6'-SL administration. Additionally, 6'-SL increased muscle mass in both the gastrocnemius (GAS) and soleus. 6'-SL administration led to an increase in the minimum Feret's diameter and the protein expression of total myosin heavy chain in the GAS muscle. In conclusion, 6'-SL administration in vivo led to increased running distance and time by increasing muscle mass and strength. These findings collectively indicate that 6'-SL is a potential agent for improving muscle health and exercise performance.


Subject(s)
Mice, Inbred C57BL , Muscle Strength , Muscle, Skeletal , Physical Conditioning, Animal , Animals , Male , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Muscle Strength/drug effects , Physical Conditioning, Animal/physiology , Mice , Lactose/analogs & derivatives , Lactose/pharmacology , Myosin Heavy Chains/metabolism , Muscle Proteins/metabolism
17.
Article in English | MEDLINE | ID: mdl-39152090

ABSTRACT

Producing double-stranded RNA (dsRNA) represents a bottleneck for the adoption of RNA interference technology in agriculture, and the main hurdles are related to increases in dsRNA yield, production efficiency, and purity. Therefore, this study aimed to optimize dsRNA production in E. coli HT115 (DE3) using an in vivo system. To this end, we designed a new vector, pCloneVR_2, which resulted in the efficient production of dsRNA in E. coli HT115 (DE3). We performed optimizations in the culture medium and expression inducer in the fermentation of E. coli HT115 (DE3) for the production of dsRNA. Notably, the variable that had the greatest effect on dsRNA yield was cultivation in TB medium, which resulted in a 118% increase in yield. Furthermore, lactose induction (6 g/L) yielded 10 times more than IPTG. Additionally, our optimized up-scaled protocol of the TRIzol™ extraction method was efficient for obtaining high-quality and pure dsRNA. Finally, our optimized protocol achieved an average yield of 53.3 µg/mL after the production and purification of different dsRNAs, reducing production costs by 72%.


Subject(s)
Culture Media , Escherichia coli , Fermentation , RNA, Double-Stranded , Escherichia coli/genetics , Escherichia coli/metabolism , RNA, Double-Stranded/genetics , Culture Media/chemistry , Genetic Vectors , Metabolic Engineering/methods , RNA Interference , Lactose/metabolism
18.
Int J Pharm ; 664: 124587, 2024 Oct 25.
Article in English | MEDLINE | ID: mdl-39147250

ABSTRACT

Predicting the mechanical properties of powder mixtures without extensive experimentation is important for model driven design in solid dosage form manufacture. Here, a new binary interaction-based model is proposed for predicting the compressibility and compactability of directly compressed pharmaceutical powder mixtures based on the mixture composition. The model is validated using blends of MCC, lactose and paracetamol or ibuprofen. Both compressibility and compactability profiles are predicted well for a variety of blend compositions of ternary mixtures for the two formulations. The model performs well over a wide range of compositions for both blends and better than either an ideal mixing model or a ternary interaction model. A design of experiments which reduces the amount of API required for fitting the model parameters for a new formulation is proposed to reduce amount of API required. The design requires only three blends containing API. The model gives similar performance to the well-known Reynolds et al. model (2017) when trained using the same data sets. The binary interaction model approach is generalizable to other powder mixture properties. The model presented in this work is limited to curve-fitting of empirical compaction models for mixtures of common pharmaceutical powders and is not intended to provide guidance on the practical operating space (or design space) limits.


Subject(s)
Acetaminophen , Ibuprofen , Lactose , Powders , Tensile Strength , Powders/chemistry , Ibuprofen/chemistry , Acetaminophen/chemistry , Lactose/chemistry , Porosity , Cellulose/chemistry , Chemistry, Pharmaceutical/methods , Drug Compounding/methods , Excipients/chemistry , Models, Theoretical
19.
Int J Pharm ; 664: 124609, 2024 Oct 25.
Article in English | MEDLINE | ID: mdl-39163928

ABSTRACT

Magnesium stearate (MgSt) and lactose fines are often used as ternary components in carrier-based dry powder inhalers (DPIs) to improve fine particle fraction (FPF), but whether they act synergistically to improve aerosolization performance of DPI formulations is currently less studied. In addition, the applicability of utilizing powder rheological parameters to predict the FPF needs to be further verified. Thus, in this study, using fluticasone propionate (FP) as a model drug, effect of lactose fines addition in 0.5% MgSt containing DPI formulations on their powder and aerodynamic properties was explored. Influence of MgSt and fines mixing order on the DPIs performance was also investigated. The results showed that addition of lactose fines (1-10%) in 0.5% MgSt containing formulations could further improve flowability and enhance adhesion of the mixtures, and they could act synergistically to improve FPF. Moreover, the presence of 0.5% MgSt can greatly reduce the amount of lactose fines required to achieve the comparable FPF. The mixing order can affect distribution of MgSt on the carrier surface, with higher FPF noted when MgSt was mixed with carrier first, followed by lactose fines. A good linear relationship between powder rheological parameters such as basic flowability energy (BFE), Permeability and FPF was disclosed. In conclusion, in FP based DPIs, MgSt and lactose fines act synergistically to enhance FPF by tuning powder characteristics. Good flowability (27.39%) and strong adhesion (72.61%) contributed to the enhanced drug deposition in the lung.


Subject(s)
Aerosols , Dry Powder Inhalers , Fluticasone , Lactose , Particle Size , Powders , Stearic Acids , Lactose/chemistry , Fluticasone/chemistry , Fluticasone/administration & dosage , Powders/chemistry , Stearic Acids/chemistry , Excipients/chemistry , Rheology , Drug Compounding/methods , Administration, Inhalation , Chemistry, Pharmaceutical/methods , Bronchodilator Agents/administration & dosage , Bronchodilator Agents/chemistry
20.
Int J Biol Macromol ; 278(Pt 2): 134810, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39154676

ABSTRACT

The current study aimed to evaluate the hydrolysis of whole fat milk (WFM) and sweet whey (SW) using ß-galactosidase (ß-gal) after covalent immobilization onto activated alginate/tea waste (Alg/TW) beads as a novel carrier. The optimum temperature for free and Alg/TW/ß-gal was 40 °C and the ideal pH was 7.0. However, Alg/TW/ß-gal displayed better stabilities at high temperatures and a wide pH range. Additionally, the value of Km and Vmax for Alg/TW/ß-gal was higher than the free enzyme. The Alg/TW/ß-gal showed better residual activity (78.6 %) after 90 storage days at 4 °C. The reusability of Alg/TW/ß-gal was very good as it conserved its full activity after 15 consecutive cycles and conserved 93 % of its initial activity after 10 cycles with ONPG (O-nitrophenyl-ß-D-galactopyranoside) and lactose as a substrate, respectively. The impact of Alg/TW/ß-gal on WFM and SW using HPLC analysis revealed a remarkable decrease in lactose concentration and increase of glucose and galactose concentrations. The SW exhibited higher degree of lactose hydrolysis (97.3 %) compared to WFM (62.4 %). Besides, SW had a prominent increase in total phenolic content (96.8 mg/L) compared to WFM (54.3 mg/L). The antioxidant activity had increased after enzyme treatment in both WFM and SW. The GC-MS analysis for volatile compounds identified twenty-five flavour constituents. Finally, Alg/TW/ß-gal has a potential application for obtaining healthy, acceptable, and commercial dairy products of low lactose.


Subject(s)
Alginates , Enzyme Stability , Enzymes, Immobilized , beta-Galactosidase , beta-Galactosidase/chemistry , beta-Galactosidase/metabolism , Alginates/chemistry , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Hydrogen-Ion Concentration , Hydrolysis , Dairy Products/analysis , Temperature , Whey/chemistry , Animals , Milk/chemistry , Lactose/chemistry , Kinetics
SELECTION OF CITATIONS
SEARCH DETAIL