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Lactase

Lactase is an enzyme responsible for the hydrolysis of lactose, the primary sugar found in milk and dairy products.
It plays a crucial role in the digestion and metabolism of lactose, allowing the body to absorb and utilize this important nutrient.
Deficiencies in lactase production can lead to lactose intolerance, a common condition characterized by gastrointestinal discomfort after consuming dairy products.
Researching lactase and its functions is essential for understanding lactose digestion, developing lactose-free products, and improving the quality of life for individuals with lactose intolerance.
The PubCompare.ai platform can help streamliene lactase research by providing access to the best protocols and leveraging AI-driven comparisons to enhance reproducibility and accuaracy.

Most cited protocols related to «Lactase»

1
Exosome-mediated Macrophage Activation and Inhibition
Cited 10 times

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Open the protocol to access the free full text link

Publication 2015
Biological Assay Cell Culture Techniques Cells Culture Media Cytokine Enzyme-Linked Immunosorbent Assay Exosomes GW 4869 Hyperostosis, Diffuse Idiopathic Skeletal Injuries Lactase Macrophage Oxidoreductase Pain Psychological Inhibition Sulfoxide, Dimethyl Technique, Dilution
2
Infant Formula with Bovine Milk Oligosaccharides
Cited 7 times
The study formulae contained sufficient amounts of proteins, carbohydrates, fats, vitamins, and minerals for normal growth of infants from birth to age 6 months. Study formulae also contained long chain polyunsaturated fatty acids and provided 67 kcal/100 ml of reconstituted formula and 1.8 g of protein/100 kcal. The control formula was a standard, commercially available whey-based infant formula (NAN 1, Nestlé Nutrition, Nestec Ltd., Vevey, Switzerland). The two BMOS-supplemented formulae (developed at Nestlé Product Technology Center, Konolfingen, Switzerland) were similar in composition to the control formula except: a) one formula (IF-BMOS) contained BMOS at a total oligosaccharide concentration of 7.3 ± 1.0 g/100 g of powder formula (10 g/L in the reconstituted formula) replacing the equivalent amount of lactose in the control formula; and b) the other formula (IF-BMOS + Pro) contained BMOS (7.3 ± 1.0 g/100 g of powder formula) as well as the probiotics Bifidobacterium longum ATCC BAA-999 (Bl999) and Lactobacillus rhamnosus CGMCC 1.3724 (LPR) each at 2 × 107 colony forming units (CFUs) per gram.
The BMOS mixture used in the formulae was derived from bovine milk whey. Briefly, an ultrafiltration permeate of bovine whey including oligosaccharides such as 3′- and 6′-sialyllactose and GOS [17 (link)] was demineralised by a combination of electrodialysis and ion exchange. Part of the remaining lactose was then enzymatically transformed into additional GOS using a fungal beta-galactosidase (Enzeco® fungal Lactase, EDC, NY). The concentration of the oligosaccharides in the final product was determined by 2-aminobenzamide labeling as described previously [18 ] and using laminaritriose as an internal standard.
Study formulae were manufactured, packaged in identical cans, and coded by the study sponsor. The investigator, study staff and caregivers were blinded to formula assignment throughout the study.
Meli F., Puccio G., Cajozzo C., Ricottone G.L., Pecquet S., Sprenger N, & Steenhout P. (2014). Growth and safety evaluation of infant formulae containing oligosaccharides derived from bovine milk: a randomized, double-blind, noninferiority trial. BMC Pediatrics, 14, 306.
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Publication 2014
6'-sialyllactose beta-Galactosidase Bifidobacterium longum Birth Bos taurus Carbohydrates Fats G-substrate GTP-Binding Proteins Infant Infant Formula Ion Exchange Lactase Lactobacillus casei rhamnosus Lactose Milk, Cow's Minerals Oligosaccharides Polyunsaturated Fatty Acids Powder Probiotics Proteins Ultrafiltration Vitamins Whey
3
GWAS with BOLT-LMM and Sensitivity Analysis
Cited 5 times
We implemented all GWAS in BOLT-LMM (10 (link)), which performs association testing using an LMM. To run, BOLT-LMM requires three primary components: the (imputed) genotypic data for association testing; a reference panel of LD scores per SNP, calculated using LD Score Regression (12 (link)); and genotype data used to approximate a genetic relationship matrix (GRM), which is the best method available in this sample size to account for all forms of relatedness, ancestral heterogeneity in the samples and other (potentially hidden) structure in the data.
We performed sensitivity testing (Supplementary
Material, Information, Supplementary
Material, Tables 12–13 and Supplementary Material, Fig. 10) using three LD Score reference datasets and four SNP sets to construct the GRM. For our final GWAS, we used LD scores calculated from a randomly selected 9748 unrelated UK Biobank samples (∼2% of the full UK Biobank sample set; Supplementary Material, Information) and a GRM constructed using imputed SNPs with imputation info score > 0.8, minor allele frequency (MAF) > 1%, Hardy Weinberg P-value > 1 × 10−8, genotype missingness < 1%, after converting imputed dosages to best-guess genotypes, LD pruned at a threshold (r2) of 0.2, and excluding the major histocompatibility complex, the lactase locus and the inversions on chromosomes 8 and 17 (Supplementary Material, Information).
Pulit S.L., Stoneman C., Morris A.P., Wood A.R., Glastonbury C.A., Tyrrell J., Yengo L., Ferreira T., Marouli E., Ji Y., Yang J., Jones S., Beaumont R., Croteau-Chonka D.C., Winkler T.W., Hattersley A.T., Loos R.J., Hirschhorn J.N., Visscher P.M., Frayling T.M., Yaghootkar H, & Lindgren C.M. (2018). Meta-analysis of genome-wide association studies for body fat distribution in 694 649 individuals of European ancestry. Human Molecular Genetics, 28(1), 166-174.
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Publication 2018
Genetic Heterogeneity Genome-Wide Association Study Genotype Hypersensitivity Inversion, Chromosome Lactase Major Histocompatibility Complex Single Nucleotide Polymorphism
4
Genotyping of SNPs in Lactase Persistence Genes
Cited 5 times
We selected 146 SNPs for genotyping from ref. 14 (link), dbSNP and the resequencing of introns 9 and 13 of MCM6 in the individuals listed above. All SNPs were genotyped in 494 samples. Following ref. 14 (link), the SNPs were chosen to represent a large area on chromosome 2 but with increased density in the LCT and MCM6 gene regions (Fig. 1a). SNPs were also included that had previously been shown to be associated with lactase persistence in Europeans (C/T-13910 and G/A-22018) or that seemed to be associated with lactase persistence based on the initial resequencing screen described above. SNP assays were designed with SpectroDESIGNER software (Sequenom). SNP typing was performed with the Homogeneous Mass Extend assay (Sequenom) as described elsewhere41 . Genotyping was carried out at a multiplex level of up to ten SNPs per well, and data quality was assessed by duplicate DNAs (n = 7 in triplicate). SNPs with more than one discrepant call or those showing self-priming in the negative control (water) were removed. Finally, we removed SNPs with call rates below 70% and flagged markers that departed from Hardy-Weinberg equilibrium (P < 0.001). A total of 123 SNPs (of which seven were monomorphic) passed quality control and were included in the final analysis; these included 79 SNPs from ref. 14 (link), 34 SNPs from dbSNP and ten SNPs from resequencing (five from intron 9 and five from intron 13) (Supplementary Table 2).
Tishkoff S.A., Reed F.A., Ranciaro A., Voight B.F., Babbitt C.C., Silverman J.S., Powell K., Mortensen H.M., Hirbo J.B., Osman M., Ibrahim M., Omar S.A., Lema G., Nyambo T.B., Ghori J., Bumpstead S., Pritchard J.K., Wray G.A, & Deloukas P. (2006). Convergent adaptation of human lactase persistence in Africa and Europe. Nature genetics, 39(1), 31-40.
Publication 2006
Biological Assay Chromosomes, Human, Pair 2 DNA Europeans Genes Introns Lactase MCM6 protein, human Single Nucleotide Polymorphism
5
Enzymatic Characterization of HoBGLA Activity
Cited 4 times
For characterization of the hydrolytic activity of HoBGLA using cellobiose and lactose, the glucose oxidase (GOD) and horseradish peroxidase (POD) assays were used as described by Kunst and coworkers (Kunst et al. 1988 ). The assay solutions were prepared by adding GOD and POD to final concentrations of 2.41 and 1.45 U/mL, respectively, to 200 mL solution of 4 mM KH2PO4, 6.4 mM 4-aminoantipyrine, and 11 mM phenol pH 7.0.
When lactose or cellobiose was used as substrate, 20 μL enzyme solutions were added to 480 μL of substrate solution in 20 mM Bis-Tris buffer pH 7. The reaction mixtures were incubated at 50 °C using an Eppendorf heat block. After 5 min, the reaction was stopped by heating the reaction mixture at 99 °C for 3 min and the sample was centrifuged at 13,000 rpm for 1 min to pellet the protein precipitate. The sample was allowed to cool at room temperature, and the release of d-glucose was assessed colorimetrically by adding 60 μL of reaction mixture to 600 μL of the GOD/POD assay solution. The assay mixture (660 μL) was incubated in the dark at room temperature for 40 min, and the absorbance at 546 nm was measured. The amount of glucose produced was calculated from a glucose standard curve obtained by adding 60 μL (0.28–3.89 mM) of standard glucose solutions to 600 μL assay solution and incubated at room temperature in the dark for 40 min. One unit of lactase activity was defined as the amount of enzyme releasing 1 μmol of d-glucose per minute under the given conditions. One unit of cellobiose activity was defined as the amount of enzyme releasing 2 μmol of d-glucose per minute under similar conditions as described for determination of β-galactosidase activity using lactose as the substrate.
Hassan N., Nguyen T.H., Intanon M., Kori L.D., Patel B.K., Haltrich D., Divne C, & Tan T.C. (2014). Biochemical and structural characterization of a thermostable β-glucosidase from Halothermothrix orenii for galacto-oligosaccharide synthesis. Applied Microbiology and Biotechnology, 99(4), 1731-1744.
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Publication 2014
Ampyrone beta-Galactosidase Biological Assay Cellobiose Enzymes Glucose glucose peroxidase Horseradish Peroxidase Hydrolysis Lactase Lactose Oxidase, Glucose Oxidases Peroxidase Phenol Proteins Tromethamine

Most recents protocols related to «Lactase»

1
Yeast-based Galactose Degradation in Foods
Not available on PMC !

Example 4

As part of evaluating the feasibility of a yeast-based approach as a treatment to mitigate the effects of elevated concentrations of galactose in foods and beverages, several evolved clones were tested for their capability of degrading galactose when present in food. Milk was tested because it represents the most challenging food for galactosemia patients considering its high level of galactose (2-4 g per 100 mL of milk). Food spiked with galactose was tested in parallel.

For this study, three evolved yeast strains obtained by adaptive evolution followed by UV treatment, Clone Y-C201-1, Clone Y-C202-1, and Clone Y-C202-2, one evolved yeast strain obtained by adaptive evolution, Clone Y-C202, as well as the initial parent strain Yi were compared for their galactose consumption activity. Cultures were initiated from a single colony on agar plates and grown in 15 mL of liquid YP medium (1% yeast extract, 2% peptone; Teknova, Hollister, CA) in a 50-mL mini-bioreactor by incubation at 30° C. with an agitation of 225 rpm supplemented with 2% galactose (Teknova). Strain Saccharomyces boulardii (SB) was prepared similarly to the evolved clones except that it was grown in YP medium supplemented with 2% glucose.

The testing of galactose consumption was started with yeast cells obtained from a culture volume containing 1.0×109 Colony Forming Units (CFU) pelleted by centrifugation at 1000 rpm (Sorval, RT7) for 10 min at room temperature. Cell pellets were resuspended either in 1.0 mL of milk already pre-treated with lactase (LACTAID milk where lactose is transformed into galactose and glucose) or in 1 mL rodent diet (Teklad, Envigo) spiked with a solution of 5% galactose or a solution of 5% galactose+1% glucose. All the reactions were incubated at 37° C. Aliquots of the reactions were taken at multiple time points and stored at −20° C. until galactose concentration determination.

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US11865151B2. Live biotherapeutics for the treatment of carbohydrate disorders (2024-01-09). GUTSYBIO INC. [US]. Inventors: Genevieve Hansen [US].
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Patent 2024
Acclimatization Agar Beverages Biological Evolution Bioreactors Cells Centrifugation Clone Cells Diet Food Galactose Galactosemias Glucose Lactaid Lactase Lactose Milk, Cow's Parent Patients Pellets, Drug Peptones Rodent Saccharomyces boulardii Strains Yeast, Dried
2
Characterization of Mouse Intestinal Contents
Cited 2 times
The abdominal cavity of mice was dissected under aseptic conditions and the small intestinal contents were removed. The contents were collected using sterilized forceps. Each group was weighed with 3 g samples of intestinal contents, put into a sterilized centrifugal tube containing glass beads, and the total weight was calculated. After collecting the intestinal contents, the small intestine was cut open along the long axis, the residual intestinal contents were rinsed with saline, and the intestinal wall tissue was blotted with filter paper to remove excess water. The intestinal mucosa was scraped and collected with a sterilized coverslip. Each group was weighed with 3 g samples of the intestinal mucosa, put into a sterilized centrifugal tube containing glass beads, and the total weight was calculated. The crude enzyme solution of intestinal content samples and intestinal mucosal samples were collected respectively. DNS (3,5-dinitrosalicylic acid) colorimetry was used to determine the activities of amylase, sucrase, and xylanase. Lactase activity was determined by the o-Nitrophenyl-β-D-Galactopyranoside (ONPG) method.11 Intestinal microbial activity was determined by the fluorescein diacetate (FDA) method.12 (link)
Li X., Zhu J., Wu Y, & Tan Z. (2023). Correlation Between Kidney Function and Intestinal Biological Characteristics of Adenine and Folium Sennae-Induced Diarrhea Model in Mice. The Turkish Journal of Gastroenterology, 34(1), 4-12.
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Publication 2023
2-nitrophenylgalactoside, (beta-D)-isomer Abdominal Cavity Acids Amylase Asepsis Colorimetry Defecation diacetylfluorescein Enzymes Epistropheus Forceps Galactose Intestinal Contents Intestinal Mucosa Intestines Intestines, Small Lactase Mice, House Saline Solution Sucrase Tissues
3
Cytotoxicity and Proliferation Assay of NIH3T3 Cells
Toxicity and cell viability were conducted by measuring lactase dehydrogenase (LDH) release and WST-1 assay, respectively. Briefly, NIH3T3 cells were cultured at 104 cells per well in a 96-well glass culture plate that had DMEM accompanied with 10% FBS for 24 h. The prepared films were cut into circular discs of 5 mm diameter and were UV-sterilized for 2 h. After sterilization, the films were placed in the wells of 96-well culture plates that had layers of the cultured NIH3T3 cells. The cells were cultured for another 24 h in contact with the films at 37 °C and under a 5% CO2 atmosphere. LDH and WST-1 kits were used, in accordance with the protocol of the manufacturer, to measure cytotoxicity and cell viability. The culture medium absorbance for LDH and cell viability was measured at 490 nm and 450 nm, respectively. LDH toxicity was calculated by the following equation.
Cytotoxicity %=A−CB−C×100 
where A represents the test substance, B represents the highly toxic control (lysis buffer), and C represents the low toxic control (tissue culture plate).
Cell proliferation of NIH3T3 cells cultured with the prepared film was determined by WST-1 assay on day 1, day 3, and day 7. NIH3T3 cells were cultured using DMEM with 10% FBS at 37 °C under a 5% CO2 atmosphere. The treatment medium was replaced every other day. On each predetermined day, WST-1 was added to the culture plate and further incubated for 4 h. Finally, the medium was transferred to a new 96-well plate, the absorbance of the medium was measured at 450 nm by SPECTROstar ® nano microplate reader, BMG Labtech, Offenburg, Germany. For LDH toxicity, cell viability, and cell proliferation, the sample size was 3 (n = 3).
Parın F.N., El-Ghazali S., Yeşilyurt A., Parın U., Ullah A., Khatri M, & Kim I.S. (2023). PVA/Inulin-Based Sustainable Films Reinforced with Pickering Emulsion of Niaouli Essential Oil for Potential Wound Healing Applications. Polymers, 15(4), 1002.
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Publication 2023
Atmosphere Biological Assay Buffers Cell Proliferation Cells Cell Survival Cultured Cells Cytotoxin Lactase NIH 3T3 Cells Oxidoreductase Sterilization Tissues
4
Quantification of Enzyme Activities
From each exposure (or control) condition, four individuals were pooled together (to average any biological variation and increase sample) and stored for analysis in liquid nitrogen. Samples were homogenized in 0.5 mL ice-cold buffer depending on the enzyme assay using an Eppendorf pestle homogenizer, and cleared with centrifugation at 20,000× g at 4 °C for 10 min. The clear supernatant was split in aliquots and assayed immediately for enzyme activities as follows. Alkaline and acid phosphatases were quantified by the production of p-nitrophenol using p-nitrophenyl phosphate (pNPP) as a substrate at pH 9.8 or 4.5, respectively. β-galactosidase activity was assessed from the concentration of o-nitrophenol released from o-nitrophenyl-β-galactosidase (ONPG) at pH 7.2 phosphate buffer [61 ]. Lipase activity was assessed by the release of p-nitrophenol from p-nitrophenyl-butyrate at pH 7.2 phosphate buffer. Peptidase activity was monitored by the release of 4-nitroaniline from the hydrolysis of L-Leu-4-nitroanilide in pH 7.2 phosphate buffer. Lactase dehydrogenase activity was assessed from the decomposition of NADH in monitoring the kinetics of the reaction of pyruvate towards lactate at 340 nm [61 ]. Glutathione-S-transferase was quantified from the conjugation of GSH to 1-chloro-2,4-dinitrobenzene monitored photometrically at 340 nm [62 (link),63 (link)]. Enzyme activity was expressed as enzyme units per protein quantified by a sensitive Bradford assay [64 (link)]. Statistically significant differences between exposures and unexposed (OECD) control and the carrier solvent were assessed following a Student’s t-test.
O’Rourke K., Engelmann B., Altenburger R., Rolle-Kampczyk U, & Grintzalis K. (2023). Molecular Responses of Daphnids to Chronic Exposures to Pharmaceuticals. International Journal of Molecular Sciences, 24(4), 4100.
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Publication 2023
4-aminophenylphosphate 4-nitrophenylphosphate Acid Phosphatase beta-Galactosidase Biological Assay Biopharmaceuticals Buffers Butyrates Centrifugation Cold Temperature Dinitrobenzenes enzyme activity Enzyme Assays Enzymes Glutathione S-Transferase Hydrolysis Kinetics Lactase Lactates Lipase NADH nitroaniline Nitrogen Nitrophenols Oxidoreductase Peptide Hydrolases Phosphates Proteins Pyruvates Solvents Student
5
Genotyping and Lactase Persistence
Genotyping was performed on the iScan System (Illumina, San Diego, CA, USA) according to the manufacturer’s recommended protocols. The quality control and imputation of rs4988235 have been described previously [7 (link)]. The LCT rs4988235 is a well-established genetic marker for non-fermented milk intake [7 (link)]. The rs4988235 genotype was categorized as CC (lactase deficiency), CT (lactase persistence), and TT (lactase persistence). Among 20,993 participants available for gene-outcome analysis, the minor allele frequency and the Hardy-Weinberg Equilibrium P value for the rs4988235 were 0.21 and 0.53, respectively.
Zhang S., Li H., Engström G., Niu K., Qi L., Borné Y, & Sonestedt E. (2023). Milk intake, lactase persistence genotype, plasma proteins and risks of cardiovascular events in the Swedish general population. European Journal of Epidemiology, 38(2), 211-224.
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Publication 2023
Genes Genetic Markers Genotype Lactase Milk

Top products related to «Lactase»

1
Lactase by Merck Group
Sourced in United Kingdom
Lactase is a lab equipment product manufactured by Merck Group. It is an enzyme that catalyzes the hydrolysis of lactose into glucose and galactose.
2
Uv 1100 by MAPADA
Sourced in China
The UV-1100 is a compact and reliable ultraviolet-visible (UV-VIS) spectrophotometer. It is designed to measure the absorbance or transmittance of samples in the ultraviolet and visible light wavelength range. The UV-1100 features a simple user interface and provides accurate and reproducible results for a variety of applications.
3
D glucose by Merck Group
Sourced in United States, Germany, United Kingdom, China, Australia, France, Italy, Canada, Sao Tome and Principe, Japan, Macao, Israel, Switzerland, Spain, Belgium, India, Poland, Sweden, Denmark, Norway, Ireland, Mexico, New Zealand, Brazil, Singapore, Netherlands
D-glucose is a type of monosaccharide, a simple sugar that serves as the primary source of energy for many organisms. It is a colorless, crystalline solid that is soluble in water and other polar solvents. D-glucose is a naturally occurring compound and is a key component of various biological processes.
4
Food grade fungal lactase by BioCat
Sourced in United States
Food grade fungal lactase is an enzyme that hydrolyzes lactose, the natural sugar found in milk and dairy products. It catalyzes the breakdown of lactose into glucose and galactose, making it suitable for use in the food industry.
5
D galactose by Merck Group
Sourced in United States, Germany, United Kingdom, Sao Tome and Principe, China, Poland, Belgium, Japan
D-galactose is a monosaccharide carbohydrate. It is a constituent of many natural polysaccharides, including lactose, cerebrosides, and gangliosides. D-galactose can be used as a laboratory reagent.
6
Du800 by Beckman Coulter
Sourced in United States, Germany, Japan, China, Canada
The DU800 is a UV/Visible spectrophotometer that provides accurate and reliable measurements for a wide range of applications in the life sciences and clinical laboratory settings. The instrument offers precise absorbance and quantification capabilities across a broad wavelength range.
7
Bca protein assay kit by Beyotime
Sourced in China, United States, Germany, Puerto Rico, United Kingdom, Switzerland, Japan, Sweden
The BCA protein assay kit is a colorimetric-based method for the quantitative determination of total protein concentration in a sample. It uses bicinchoninic acid (BCA) to detect and quantify the presence of protein.
8
Ldh cytotoxicity detection kit by Takara Bio
Sourced in Japan, United States, France, China
The LDH Cytotoxicity Detection Kit is a laboratory equipment product that measures the activity of lactate dehydrogenase (LDH) enzyme released from damaged cells. This assay provides a quantitative method to determine cytotoxicity or cell death.
9
Cytation 3 plate reader by Agilent Technologies
Sourced in United States
The Cytation 3 is a multi-mode microplate reader designed for diverse cell-based and biochemical applications. It combines high-performance detection technologies, including fluorescence, luminescence, and absorbance, within a compact, automated instrument.

More about "Lactase"

Lactase is a crucial enzyme responsible for the hydrolysis of lactose, the primary sugar found in milk and dairy products.
It plays a vital role in the digestion and metabolism of this important nutrient, allowing the body to effectively absorb and utilize it.
Deficiencies in lactase production can lead to lactose intolerance, a common condition characterized by gastrointestinal discomfort after consuming dairy items.
Researching lactase and its functions is essential for understanding lactose digestion, developing lactose-free products, and improving the quality of life for individuals with lactose intolerance.
The PubCompare.ai platform can help streamline this research by providing access to the best protocols and leveraging AI-driven comparisons to enhance reproducibility and accuracy.
This innovative tool can assist in locating the most relevant and reliable protocols from literature, preprints, and patents, making the research process more efficient and effective.
By utilizing PubCompare.ai, researchers can enhance the reproducibility and accuracy of their lactase-related studies, leading to more robust and reliable findings.
Understanding the intricate workings of lactase, the enzyme responsible for breaking down lactose, is crucial for advancements in the field of lactose digestion and management of lactose intolerance.
The UV-1100 spectrophotometer, D-glucose, Food grade fungal lactase, D-galactose, DU800 spectrophotometer, BCA protein assay kit, and LDH Cytotoxicity Detection Kit are all valuable tools and reagents that can be utilized in lactase research, helping to provide a more comprehensive understanding of this essential enzyme and its functions.
By leveraging the power of PubCompare.ai and incorporating these related terms and resources, researchers can streamline their lactase-focused investigations, leading to breakthroughs in the management of lactose intolerance and the development of innovative lactose-free products that cater to the needs of individuals with this common condition.