lactose

Definitions

  • WordNet 3.6
    • n lactose a sugar comprising one glucose molecule linked to a galactose molecule; occurs only in milk "cow's milk contains about 4.7% lactose"
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Webster's Revised Unabridged Dictionary
  • Interesting fact: Being lactose intolerant can cause chronic flatulence
    • lactose (Chem) See Galactose.
    • lactose (Physiol. Chem) The main sugar present in milk, called also sugar of milk or milk sugar. When isolated pure it is obtained crystalline; it is separable from the whey by evaporation and crystallization. It is a disaccharide with the formula C12H22O11, being chemically 4-(β-D-galactosido)-D-glucose. It has a slightly sweet taste, is dextrorotary, and is much less soluble in water than either cane sugar or glucose. Formerly called lactin. When hydrolyzed it yields glucose and galactose. In cells it may be hydrolyzed by the enzyme β-galactosidase.
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Century Dictionary and Cyclopedia
  • Interesting fact: For people that are lactose intolerant, chocolate aids in helping milk digest easier
    • n lactose Sugar of milk, C12H22O11, obtained by evaporating whey, filtering through animal charcoal, and crystallizing. It forms hard, white, semi-transparent trimetric crystals, which are less soluble than cane-or grape sugar, have a slightly sweet taste, and grate between the teeth. It is dextrogyrate, and ferments slowly with yeast, but readily undergoes the lactic fermentation. It is convertible into glucose and galactose by boiling with dilute sulphuric acid. It is used for food and in medicine, and is prepared as an article of commerce in Switzerland and Bavaria. Also called galactine lactine, and milk-sugar.
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Chambers's Twentieth Century Dictionary
    • Lactose a kind of sugar, only moderately sweet, obtained from milk by evaporating whey—also Lac′tine
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Etymology

Chambers's Twentieth Century Dictionary
L. lacteus, milky—lac, lactis, milk; Gr. gala, galaktos, milk.

Usage

In literature:

This is due to the fact that lactose undergoes the lactic acid fermentation.
"A Practical Physiology" by Albert F. Blaisdell
Milk is composed of water, salts, fat, milk sugar or lactose, albumen and casein.
"Public School Domestic Science" by Mrs. J. Hoodless
The lactose nitrate is more stable.
"Researches on Cellulose" by C. F. Cross
Laevulose, galactose, maltose, lactose, etc., can be substituted in similar amounts for dextrose and the medium completed as above.
"The Elements of Bacteriological Technique" by John William Henry Eyre
Not only gas-forming bacteria may be the cause of gassy cheese, but the lactose-fermenting yeasts may cause similar trouble.
"Outlines of dairy bacteriology" by H. L. Russell
Herter claims that sucrose and glucose are much more so than lactose, maltose, or starch.
"Dietetics for Nurses" by Fairfax T. Proudfit
The disaccharide =lactose= is a glucose-galactoside.
"The Chemistry of Plant Life" by Roscoe Wilfred Thatcher
Horsford prepared condensed milk with the addition of lactose.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5" by Various
A number of the strains that survived several treatments were cultivated in lactose broth and the acidity determined quantitatively.
"Chlorination of Water" by Joseph Race
Control of casein or lactose, on the contrary, is not nearly so practicable.
"The Book of Cheese" by Charles Thom and Walter Warner Fisk
Hess and Unger failed to cure infantile scurvy by means of lactose.
"Scurvy Past and Present" by Alfred Fabian Hess
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In news:

For everyone calling me anorexic I have a gluten and lactose allergy.
Chinese low-lactose calf is likely just the beginning of dairy applications.
Consumers are increasingly demanding the development of ready-to-eat gluten and lactose -free food products that meet their needs and help improve their health.
Milk's Inherent Prebiotic: Lactose .
Genes enabling lactose tolerance, which probably resulted in more surviving offspring, were detected in cultures like this Kenyan shepherd's.
"But Stifler I'm lactose intolerant.".
Archaeologists believe that ancient farmers used pots made from these pottery shards to make cheese †a less perishable, low-lactose milk product.
Standard Unispheres are based on mannitol or lactose.
Lactose intolerance is just one health consideration among many in Eldon Lemons' family.
Consumers are increasingly demanding the development of ready-to-eat gluten and lactose-free food products that meet their needs and help improve their health.
Signs you may be lactose intolerant .
According to the National Institute of Child Health & Human Development, between 30 and 50 million Americans are lactose intolerant .
For example, the Broward County Public Schools in Florida have been offering soy milk to any lactose- intolerant child whose parent requests it, but officials say the option is not widely advertised because of the costs involved.
Lactose Free and GO Veggie.
And, even if your child has problems digesting lactose, he or she can probably still eat or drink.
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In science:

Finzi L, Gelles J (1995) Measurement of lactose repressor-mediated loop formation and breakdown in single DNA molecules.
Concentration and Length Dependence of DNA Looping in Transcriptional Regulation
Interconvertable lactose repressorDNA looped complexes revealed by single-molecule experiments.
Concentration and Length Dependence of DNA Looping in Transcriptional Regulation
Barry JK, Matthews KS (1999) Thermodynamic analysis of unfolding and dissociation in lactose repressor protein.
Concentration and Length Dependence of DNA Looping in Transcriptional Regulation
Goeddel DV, Yansura DG, Caruthers MH (1977) Binding of synthetic lactose operator DNAs to lactose represessors.
Concentration and Length Dependence of DNA Looping in Transcriptional Regulation
Lewis M, Chang G, Horton NC, Kercher MA, Pace HC, et al. (1996) Crystal structure of the lactose operon repressor and its complexes with DNA and inducer.
Concentration and Length Dependence of DNA Looping in Transcriptional Regulation
Falcon CM, Swint-Kruse L, Matthews KS (1997) Designed disulfide between Nterminal domains of lactose repressor disrupts allosteric linkage.
Concentration and Length Dependence of DNA Looping in Transcriptional Regulation
Using this method, Voight and colleagues find strong evidence for recent selection among Europeans in the lactase gene LCT, which is important for metabolism of lactose beyond early childhood.
The transmission sense of information
Ozbudak E, Thattai M, Lim H, Shraiman B, van Oudenaarden A: Multistability in the lactose utilization network of Escherichia coli.
TinkerCell: Modular CAD Tool for Synthetic Biology
So long as the proton tunnelling is irrelevant to the growth of the bacteria (no lactose present), then ‘no -one’ is looking in the well and the system will remain at the quantum level until thermal decoherence collapses the system into either state.
Comment on Book Review of `Quantum Evolution' (Johnjoe McFadden) by Mathew J. Donald
However, with lactose present, the tunnelling can cause a mutation that will allow the bacterium to grow (with lactose present).
Comment on Book Review of `Quantum Evolution' (Johnjoe McFadden) by Mathew J. Donald
The mutational process will thereby demonstrate decay kinetics with the proportion of cells in the mutant state increasing with time – but only if lactose is present: adaptive mutations.
Comment on Book Review of `Quantum Evolution' (Johnjoe McFadden) by Mathew J. Donald
The lac promoter controls genes that are responsible for lactose utilization by bacteria.
A First Exposure to Statistical Mechanics for Life Scientists
When the operon is “on”, the bacterium produces the enzymes necessary to import and digest lactose.
A First Exposure to Statistical Mechanics for Life Scientists
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