chembox Verifiedfields changed verifiedrevid 477497006 Name Lactose Milk sugar ImageFile Ref chemboximage ... 202.8 C ref name Ald Anonymous. Sigma Aldrich. Lactose Product. http www.sigmaaldrich.com catalog ... BoilingPt 668.9 C ref name Ald Solubility 21.6 g 100 mL ref The solubility of lactose in water ... Coutinho first3 Eug nia A. last3 Macedo title Solid liquid equilibrium of lactose in ethanol water ... FlashPt 357.8 C ref name Ald Autoignition Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose . Lactose makes up around 2 8 of milk by weight ... used to name sugars. It has a formula of C sub 12 sub H sub 22 sub O sub 11 sub . History Lactose ... Wilhelm Scheele . ref name Linko1981 citation year 1982 author Linko, P chapter Lactose and Lactitol ... publisher Applied Science Publishers isbn 0 85334 997 5 ref Structure and reactions File Alpha lactose from xtal 3D balls.png thumb left The molecular structure of lactose, as determined by X ray crystallography . Lactose is a disaccharide derived from the condensation of galactose and glucose ... the galactose can only have the pyranose form hence lactose and lactose refer to anomer ic form of the glucopyranose ring alone. Lactose is hydrolysed to glucose and galactose, isomerised in alkaline ... of the dairy industry. Whey is made of up 6.5 solids of which 4.8 is lactose that may be purified ... remaining after milk is curdled and strained, for example in the production of cheese. Lactose makes up about 2 8 of milk by weight. Lactose is purified from whey by adding ethanol. Since it is insoluble in ethanol, lactose precipitates in about 65 yield. ref Minard, R. Introduction to Organic Laboratory ... Main Lactose intolerance Infant mammal s nurse on their mothers to drink milk, which is rich in lactose ... it. This enzyme cleaves the lactose molecule into its two subunits, the simple sugar s glucose and galactose , which can be absorbed. Since lactose occurs mostly in milk, in most mammals the production ... more details
Lactose synthase is an enzyme that generates lactose from glucose and UDP galactose . It is classified under EC number 2.4.1.22 . It consists of N acetyllactosamine synthase and alpha lactalbumin . Alpha lactalbumin, which is expressed in response to prolactin , increases the affinity of N acetyllactosamine synthase for its substrate, causing increased production of lactose during lactation. External links MeshName Lactose synthase Glycosyltransferases Fructose and galactose metabolism Category EC 2.4.1 biochem stub it Lattosio sintasi ja ... more details
Infobox disease Name Lactose Intolerance Image Lactose Haworth.svg Caption Lactose disaccharide of ... med eMedicineTopic 3429 eMedicine mult eMedicine2 ped 1270 MeshID D007787 Lactose intolerance , also called lactase deficiency and hypolactasia , is the inability to digest lactose , a sugar found in milk and hence some dairy products . Lactose intolerant individuals have insufficient levels of lactase , the enzyme that Metabolism metabolizes lactose into glucose and galactose , in their digestive ... web title Lactose Intolerance url http digestive.niddk.nih.gov ddiseases pubs lactoseintolerance work ... 2011 ref after consuming significant amounts of lactose. Most mammal s normally become lactose intolerant ... 0286 27939567 ITM title Improved lactose digestion and intolerance among African American adolescent ... loses the ability to completely digest a physiological dose of lactose after infancy work pmid 10812376 ... R.B. last6 Silveira first6 T.R. title Correlation between lactose absorption and the C T 13910 and G ... doi 10.1590 S0100 879X2007001100004 ref Terminology Lactose intolerance primarily refers to a syndrome having one or more symptoms upon the consumption of food substances containing lactose. Individuals may be lactose intolerant to varying degrees, depending on the severity of these symptoms. Lactose malabsorption refers to the physiological concomitant of lactase deficiency i.e. the body does not have sufficient lactase capacity to digest the amount of lactose ingested . ref name Heyman ... doi 10.1038 ng826 ref It is the most common cause of lactose intolerance as a majority of the world ... AD, Klein RM title Lactose intolerance journal Am Fam Physician volume 65 issue 9 pages 1845 50 year ... ref name eMedicine pediatric Emedicine emerg 930971 Pediatric Lactose Intolerance ref Congenital ... 2303. ref Lactose intolerance is not an Food allergy allergy because it is not an Immune system immune ... to lactose. Most people with lactose intolerance can tolerate some amount of lactose in their diet ... more details
Infobox protein family Symbol Name LacY proton sugar symporter image 2y5y.png width caption Crystal Structure of Lactose Permease in Complex with an Affinity Inactivator. PDB PDBe 2y5y ref cite pmid 21593407 ref Pfam PF01306 Pfam clan CL0015 InterPro IPR022814 SMART PROSITE PDOC00698 MEROPS SCOP TCDB 2.A.1 OPM family 15 OPM protein 2cfq CAZy CDD Lactose permease is a membrane protein which is a member of the major facilitator family major facilitator superfamily . Lactose permease can be classified as a symporter , which uses the gradient of H towards the cell to transport lactose in the same direction into the cell. The protein has twelve transmembrane helix transmembrane helices and exhibits an internal two fold symmetry, relating the N terminal six helices onto the C terminal helices. The sugar lies in a pocket in the center of the protein which is accessible from the periplasm. On binding, a large conformational change takes place which makes the sugar binding site accessible from the cytoplasm. The X ray crystal structure was first solved in 2003 by J. Abramson et al. ref cite pmid 12893935 ref References Reflist Category Transport proteins Category Transmembrane proteins ca Lactosa permeasa ... more details
Unreferenced date December 2009 File A clear CLED agar plate after cultivation.jpg thumb A clear CLED agar plate after cultivation File Lactose non lactose fermenters on CLED agar.jpg thumb Colonies of lactose and non lactose fermenting bacteria on CLED agar CLED agar cystine lactose electrolyte wikt deficient deficient medium is a valuable non inhibitory growth medium used in the isolation and differentiation of urine urinary organisms. Being electrolyte deficient, it prevents the swarming of Proteus bacterium Proteus species. Cystine promotes the formation of cystine dependent dwarf colonies. Lactose fermenters produce yellow Colony biology colonies on CLED agar non lactose fermenters appear blue. It has a pH of approximately 7.3. CLED agar contains class wikitable Peptide Peptone 4g l Lab Lemco powder 3g l Tryptone 4g l Lactose 10g l L Cystine 128 mg l Bromothymol blue 20 mg l Agar No. 1 15g l Growth media DEFAULTSORT Cysteine Lactose Electrolyte Deficient Agar Category Microbiological media ca Agar CLED de C.L.E.D. Agar es Agar CLED pt gar CLED ... more details
Notability Products date March 2011 Lactofree is a brand of lactose free ref http www.food.gov.uk multimedia pdfs publication understandfoodlabellingterms.pdf Food Standards Agency ref dairy products aimed at individuals with lactose intolerance . The brand was launched by Arla Foods UK in 2006 and is available in the UK . ref http www.just food.com news arla launches lactose free dairy drink id87826.aspx Just Food, January 27, 2006 ref In September 2010, Lactofree began licensing its lactose removing patent to other producers. ref http www.foodmanufacture.co.uk Manufacturing Arla offers licence for lactose free dairy expertise Food Manufacture, Sep 1 2010 ref Up to September 2010, Lactofree had seen a 37 growth year on year. ref http www.foodmanufacture.co.uk Business News Lactofree sales up 37 as Arla posts profit surge Food Manufacture, September 1, 2010 ref References Reflist External links http www.lactofree.co.uk Lactofree Category Food brands of the United Kingdom Category Companies based in Leeds ... more details
of lactose intolerance . As of 2011, Ritter Pharmaceuticals ceased sales of Lactagen and other ... , and abdominal pain abdominal cramping which are associated with the symptoms of lactose intolerance. ref Schaeffer, Juliann. Ice Cream for All? Lactagen and Lactose Intolerance. Todays Dietician Apr ... can relieve symptoms of lactose intolerance, but relief may not be permanent. ref name Post cite ... Ritter created a lactose intolerance treatment in 1997 as a project for the California State Science Fair . ref name Post A lactose intolerant individual himself, Ritter collaborated with doctors and researchers to create a product to help individuals better tolerate lactose . ref cite web last ... 2010 year 2008 ref Lactose intolerance main Lactose intolerance Lactose intolerance is caused by a lack of the naturally produced enzyme lactase in the stomach. Lactose intolerance is exemplified by the inability ... or diarrhea. ref Cite web last Bowen first R. date 28 December 2006 title Lactose Intolerance Lactase ... url http www.vivo.colostate.edu hbooks pathphys digestion smallgut lactose intol.html accessdate ... Landon, M.D., Lactagen showed a statistically significant reduction in lactose intolerance symptoms ..., California. Specifically, 79 of subjects on Lactagen reported a substantial reduction of lactose ... for Lactose Intolerance Clinical Study Proves Lactagen s Revolutionary 38 Day Program Allows Sufferers ... At the National Institute of Health Consensus Development Conference on Lactose Intolerance ... data and may be useful for individuals with lactose intolerance, although additional research needs ... NIH Consensus Development Conference Lactose Intolerance and Health url http consensus.nih.gov 2010 images lactoselactose finalstatement.pdf accessdate 24 February 2010 ref A study published ... to regular lactose ingestion and the related adaption reduces lactose intolerance symptoms. ref Colonic adaptation to daily lactose feeding in lactose maldigesters reduces lactose intolerance, American ... more details
unreferenced date April 2012 The abundance availability of milk and its production may leads to useful product and byproducts for both infants and elderly people. The hydrolysis of lactose is desirable to overcome the problem of its moderate solubility in concentrated milk products and to ensure its easy digestion for both cases of lactose intolerant infants and adults. Immobilized Enzyme Reactor System DFRL, DRDO developed a bio reactor to make the hydrolysis of the lactose a cost effective method, novel and simple to operate either in batch or continuous mode. The bio catalyst if reused for several times can contribute to improve the cost benefit ratio. The lactose hydrolysis is carried out either at 5 150 C or 350 C drastically reduce the microbial contamination in the bio reactor developed. The bio reactor can hold immobilized enzyme whole cell catalysts at high density and varying operational temperature. This bio reactor is able to retain immobilized bio catalysts prepared in form of granules, blocks, or fibrous materials. This instrument can provide long term mechanical and biochemical stability to immobilized enzyme preparations and effective hydrolysis of lactose in closed loop. The system achieved hydrolysis purity of 98 in milk. The economy and process efficiency of lactose hydrolysis in milk improved using this continuous flow bio reactor. The technology is economical and micro biologically safe. References reflist Category Milk Category Milk substitutes kn ... more details
Unreferenced stub auto yes date December 2009 In biochemistry , a product is something manufactured by an enzyme from its enzyme substrate substrate . An example of this would be the products of lactase are galactose and glucose , which are produced from the substrate lactose . Image lactose hydrolysis.svg thumb left 500px Reaction using lactase clear left See also Enzyme substrate DEFAULTSORT Product Biology Category Cell biology Cell biology stub sr Produkt biologija th ... more details
Lactosylceramide is a type of ceramide incorporating lactose . ref MeshName Lactosylceramides ref An example is CDw17 antigen . See also Lactosylceramide 1,3 N acetyl beta D glucosaminyltransferase Lactosylceramide alpha 2,3 sialyltransferase GAL3ST1 ST3GAL5 References Reflist Category Lipids biochem stub Sphingolipids ... more details
and texture to traditional dairy ice cream . ref Doris E. Pitz. Lactose Free Synthetic Ice Cream ... lactose. Soy beverages are developed by extracting the liquid from ground up soybeans . It comes ... more details
unphosphorylated form. This leads to inhibition of adenylyl cyclase and lactose permease , therefore Cyclic adenosine monophosphate cAMP levels are low and lactose can not be transported inside the bacteria ... lactose has to be used by bacteria. Absence of glucose will turn off catabolite repression. Furthermore ... on the lac operon . However, this is not enough for the lactose genes to be transcribed. Lactose must be present inside the cell to remove the lactose repressor from the operator sequence transcriptional ... is absent and lactose is available. Next, bacteria start to transcribe lactose gene and produce galactosidase enzymes for lactose metabolism. The example above is a simplification of a complex process ... more genes rather than just lactose gene transcription. ref Cite journal doi 10.1016 j.mib.2008.02.007 ... more details
galactoside permease is a cell membrane membrane bound Membrane transport protein transport protein that active transport pumps lactose into the cell biology cell . See also lac operon permease galactoside External links MeshName Permease, beta galactoside Category Transport proteins enzyme stub ... more details
N acetyllactosamine synthase is a galactosyltransferase enzyme. It is a component of lactose synthase . It is classified under EC number 2.4.1.90 . See also N Acetylglucosamine External links MeshName N acetyllactosamine synthase Glycosyltransferases Category EC 2.4.1 biochem stub it N acetillattosammina sintasi sr N acetillaktozamin sintaza ... more details
unreferenced date June 2011 A diauxic growth curve refers to the growth curve generated by an organism which has two growth peaks. The theory behind the diauxic growth curve stems from Jacques Monod Jacques Monod s Ph.D. research in 1940. A simple example involves the bacterium Escherichia coli E. coli , the best understood bacterium. The bacterium is grown on a growth media containing two types of sugars , one of which is easier to metabolism metabolize than the other for example glucose and lactose . First, the bacterium will metabolize all the glucose, and grow at a higher speed. Eventually, when all the glucose has been consumed, the bacterium will begin the process of expressing the gene genes to metabolize the lactose. This will only occur when all glucose in the media has been consumed. For these reasons, diauxic growth occurs in multiple phases. The first phase is the fast growth phase , since the bacterium is consuming in the case of the above example exclusively glucose, and is capable of rapid growth. The second phase is a lag phase while the genes used in lactose metabolism are expressed and observable cell growth stops. This is followed by another growth phase which is slower than the first because of the use of lactose as the primary energy source. The final stage is the saturation phase . Category Cell biology ... more details
Orphan date February 2009 Lauryl tryptose broth LSB is a selective growth medium for coliform s. The American Public Health Association APHA recommends that lauryl tryptose broth should be used for the Mean Probable Number Presumptive Test of coliforms in waters, effluent or sewage as a confirmatory test of lactose industrial fermentation fermentation with gas production for milk samples.Sodium lauryl sulfate inhibits organism other than coliforms. Formula in grams litre g l Tryptose 20.0, Lactose 5.0, Sodium chloride 5.0, Dipotassium phosphate 2.75, Potassium dihydrogen phosphate 2.75, Sodium dodecyl sulfate 0.1 pH 6.8 0.2 External links http www.apha.org American Public Health Association website Category Microbiological media Microbiology stub ... more details
Sorbitol MacConkey agar is a variant of traditional MacConkey agar used in the detection of E. coli O157 H7 E. coli O157 H7. ref name pmid10655343 cite journal author Novicki TJ, Daly JA, Mottice SL, Carroll KC title Comparison of sorbitol MacConkey agar and a two step method which utilizes enzyme linked immunosorbent assay toxin testing and a chromogenic agar to detect and isolate enterohemorrhagic Escherichia coli journal J. Clin. Microbiol. volume 38 issue 2 pages 547 51 year 2000 month February pmid 10655343 pmc 86145 doi url http jcm.asm.org cgi pmidlookup?view long&pmid 10655343 ref Traditionally, MacConkey agar has been used to distinguish those bacteria that ferment lactose from those that do not. This is important because gut bacteria, such as Escherichia coli , can typically ferment lactose, while important gut pathogens, such as Salmonella enterica and most shigellas are unable to ferment lactose. Shigella sonnei can ferment lactose, but only after prolonged incubation, so it is referred to as a late lactose fermenter . During fermentation of the sugar, acid is formed and the pH of the medium drops, changing the color of the pH indicator. Different formulations use different indicators neutral red is often used. For example, lactose fermenters turn a deep red when this pH indicator is used. Those bacteria unable to ferment lactose, often referred to as nonlactose fermenters , or NLFs for short, use the peptone in the medium. This releases ammonia, which raises the pH of the medium. Although some authors refer to NLFs as being colourless, in reality they turn neutral red a buffish color. E. coli O157 H7 E. coli O157 H7 differs from most other strains of E. coli in being unable to ferment sorbitol . In sorbitol MacConkey agar, lactose is replaced by sorbitol. Most strains of E. coli ferment sorbitol to produce acid E. coli O157 H7 can not ferment sorbitol, so this strain uses peptone to grow. This raises the pH of the medium, allowing the O157 H7 strain to ... more details
Image MacConkey agar with LF and LF colonies.jpg thumb right Macconkey agar with lactose left and non lactose right fermenters Image Proteus McConkey.jpg thumb right A MacConkey agar plate with an active bacterial culture. Image Lactose3.png thumb Lactose Alfred Theodore MacConkey MacConkey agar is a Microbiological culture culture Selective medium medium designed to grow Gram negative bacteria and Staining stain them for lactose industrial fermentation fermentation . ref name url cite web url http medic.med.uth.tmc.edu path macconk.htm title tmc.edu work accessdate ref Contents It contains bile salts to inhibit most Gram positive bacteria, except Enterococcus and some species of Staphylococcus i.e. Staphylococcus aureus , crystal violet dye which also inhibits certain Gram positive bacteria , neutral red dye which stains microbes fermenting lactose , lactose and peptone . Composition ref http www.microbelibrary.org index.php component resource laboratory test 2855 macconkey agar plates protocols ref Peptone 17 g Proteose peptone 3 g Lactose 10 g Bile salts 1.5 g Sodium chloride 5 g Neutral red 0.03 g Agar 13.5 g Water add to make 1 litre adjust pH to 7.1 0.2 There are many variations of MacConkey agar depending on the need. If the spreading or swarming of Proteus species is NOT required, sodium chloride is omitted. Crystal violet at a concentration of 0.0001 0.001 g per litre is included ... negative bacteria that can ferment the sugar lactose Lac from those that cannot Lac . This medium is also ... swarming by Proteus species. Lac By utilizing the lactose available in the medium, Lac bacteria ... to become hazy. ref cite journal author MacConkey AT year 1905 title Lactose Fermenting Bacteria .... journal J Hyg Lond volume 8 pages 322 34 pmid 20474363 issue 3 ref Lac Non Lactose fermenting ... cannot utilize lactose, and will use peptone instead. This forms ammonia , which raises the pH of the agar ... Some organisms ferment lactose slowly or weakly, and are sometimes put in their own category. These include ... more details
Hektoen enteric agar HEK or HE or HEA is a selective and differential agar ref name pmid4584576 cite journal author Goo VY, Ching GQ, Gooch JM title Comparison of brilliant green agar and Hektoen enteric agar media in the isolation of salmonellae from food products journal Appl Microbiol volume 26 issue 3 pages 288 92 year 1973 month September pmid 4584576 pmc 379776 doi url ref primarily used to recover Salmonella and Shigella from patient specimens. HE contains indicators of lactose fermentation and H sub 2 sub S production as well as inhibitors to prevent the growth of gram positive bacteria . The pattern of lactose fermentation and H sub 2 sub S production aids in the identification of the organism subbed to the plate. Specifically, Salmonella produces black colonies, whereas Shigella produces translucent green colonies. The color of the agar itself is green. Sugars in media usually include lactose, sucrose, and salicin. See also Microbiology Agar plate References reflist External links http www.mpbio.com product info.php?products id 10047 More details of HEK Growth media Category Microbiological media ar id Hektoen Enteric Agar th Hektoen enteric agar ... more details
In biology, the Goodwin model describes negative feedback Oscillators Biological oscillators in cellular systems ref Goodwin, B. Oscillatory behavior in enzymatic control processes. Advances in Enzyme Regulation, 3, 1965, pages 425&ndash 428. doi 10.1016 0065 2571 65 90067 1 ref , for example, circadian rhythm s or enzymatic regulation such as lactose in bacteria . The Goodwin model, though, shows no stable limit cycle s. References reflist Category Biology biology stub ... more details
lowercase title Lac operon The lac operon is an operon required for the transport and metabolism of lactose ... of glucose and of lactose . Gene regulation of the lac operon was the first complex genetic regulatory ... allows for the effective digestion of lactose. The cell can use lactose as an energy source by producing the enzyme Beta galactosidase galactosidase to digest that lactose into glucose and galactose . However, it would be inefficient to produce enzymes when there is no lactose available, or if there is a more ... repressor , which halts the production in the absence of lactose, and the catabolite activator protein ... the sequential utilization of glucose and lactose in two distinct growth phases, known as diauxie ... operon Image Lactose etc.png thumb 300px Structure of lactose and the products of its cleavage ... enzyme that cleaves the disaccharide lactose into glucose and galactose . lacY encodes ... that pumps lactose into the cell. lacA encodes beta galactoside transacetylase galactoside ... galactoside s. Only lacZ and lacY appear to be necessary for lactose catabolism . Specific control of the lac genes depends on the availability of the substrate biochemistry substrate lactose to the bacterium. The proteins are not produced by the bacterium when lactose is unavailable as a carbon source ... 146575 view . The first control mechanism is the regulatory response to lactose, which uses an intracellular regulatory protein called the lactose repressor to hinder production of Beta galactosidase galactosidase in the absence of lactose. The lacI gene coding for the repressor lies nearby the lac operon and is always expressed constitutive . If lactose is missing from the growth medium, the repressor .... When cells are grown in the presence of lactose, however, a lactose metabolite called allolactose ... the production of Beta galactosidase galactosidase , enabling the cell to hydrolyse digest lactose ... to use lactose , His the ability to synthesize the amino acid histidine Mot swimming motility Sm sup ... more details
Image Soymilk flickr user juanstermonster.jpg thumb 250px So Good Original soy milk in the 1.89l carton. So Good also known as SoGood or So Good is a brand of fortified soymilk soy beverages that is lactose, cholesterol and preservative free. So Good is manufactured by Sanitarium Health Food Company Sanitarium in Australia and New Zealand. In Canada it is prepared by Earth s Own. So Good sold in the United Kingdom is manufactured by So Good International Ltd. See also Lactose intolerance Milk allergy Soy allergy Soy yogurt Veganism Vegetarian cuisine External links http www.sogood.sanitarium.com.au Australian So Good Site http www.sogoodbeverage.com Canadian So Good Site http www.sogood.co.uk United Kingdom So Good Site Milk substitutes Soy state collapsed Category Soy products Category Milk substitutes nonalcoholic drink stub ... more details
the following ingredients Pancreatic digest of gelatin, Lactose, Dipotassium phosphate, Eosin Y dye , Methylene blue dye , Agar There are also EMB agars that do not contain lactose References reflist ... more details
that such DPIs are normally used only in older children and adults. Lactose Some powder inhalers use lactose as bulking agent and to aid in powder uptake from the device during inhalation. While some have suggested that such lactose may be harmful to lactose intolerant people, ref http www.redorbit.com ... in Inhaler Devices for Asthma And COPD Health RedOrbit Bot generated title ref the lactose dose delivered ... relevant concerns of adverse effects in lactose intolerant patients. Storage DPI medication ... more details
and Transcription genetics transcribe the genes involved in lactose catabolism . ref name Busby ref name Lawson Thus, CAP enhances the expression of the lac operon when lactose is present, but not glucose ... to lactose. The cell prefers glucose, and, if it is available, the lac operon is not activated, even when lactose is present. This is an effective way of integrating the two different signals ... more details
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