Left Handed Sugar
David Adams
Some time back I remember hearing about left handed sugar. This was
suppose to be an artificial substance with the same chemical structure
as regular sugar except that the molecules were arranged on a left
handed basis instead of a right handed basis. The nice thing about
it was that it tasted and acted just like regular sugar except it
could not be metabolised by the body and therefore had no calories.
It was supposed to be the dieters dream.
Fact, fiction, or being kept off the market by the sugar producers?
David "fructose, glucose, sucrose, all the same to me" Adams
--
| David Adams | Per request by JXXX FXXX, all references to |
| ve...@netcom.com | Vicki Robinson have been removed from this .sig. |
Carl J Lydick
=
=
=Some time back I remember hearing about left handed sugar. This was
=suppose to be an artificial substance with the same chemical structure
=as regular sugar except that the molecules were arranged on a left
=handed basis instead of a right handed basis. The nice thing about
=it was that it tasted and acted just like regular sugar except it
=could not be metabolised by the body and therefore had no calories.
=It was supposed to be the dieters dream.
=
=Fact, fiction, or being kept off the market by the sugar producers?
=David "fructose, glucose, sucrose, all the same to me" Adams
FRUCTOSE == levulose
GLUCOSE == dextrose
SUCROSE == one each of levulose and dextrose, bonded together.
Glucose is blood sugar. It's the sugar the body's set up to metabolize most
effectively. Fructose is easily converted to glucose, but that extra step
means it sin't metabolized so easily. Sucrose is split into glucose and
fructose, then the fructose is converted to glucose. All have approximately
the same caloric content per gram. However, the sweetness of these three
sugars varies considerably. On a sweetness scale where sucrose is 1.0, glucose
is about 0.7 and fructose is about 1.7. So if you want to maximize
sweetness/calorie, you want fructose. If you've just accidentally injected
insulin into a vein (as I managed to do once), you want glucose.
--------------------------------------------------------------------------------
Carl J Lydick | INTERnet: CA...@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL
Disclaimer: Hey, I understand VAXen and VMS. That's what I get paid for. My
understanding of astronomy is purely at the amateur level (or below). So
unless what I'm saying is directly related to VAX/VMS, don't hold me or my
organization responsible for it. If it IS related to VAX/VMS, you can try to
hold me responsible for it, but my organization had nothing to do with it.
David Smillie
Yes, it is theoretically possible to use the left-handed form of sugar. It
would have the same mass and presumably the same sweetness (though I don't
know for sure if it would interact with our taste buds) but it would be
zero calories.
The reason is, all of our enzymes are specific to break down the
right-hand form of sugars. Give us the left-handed version and they won't
fit into the catalytic sites. Consequently there will be no breakdown of
the sugar, no metabolism and no calories. So in theory the left-sugars
could be used in baking to produce the same physical properties as sugar,
but not the high calories.
In theory, anyway. I'm not so sure it would interact in the same way with
our taste buds, but I'm willing to reserve judgement.
--
_____________________________________________________________________________
David Smillie, Carleton University Ancora imparo
"I'd rather be happy than right any day."
"But are you?"
"What?"
"Happy."
"No," he said with a sigh, "That's where it all falls down, of course."
_____________________________________________________________________________
mi...@baobab.cadif.cornell.edu
>
>Yes, it is theoretically possible to use the left-handed form of sugar. It
>would have the same mass and presumably the same sweetness (though I don't
>know for sure if it would interact with our taste buds) but it would be
>zero calories.
>The reason is, all of our enzymes are specific to break down the
>right-hand form of sugars. Give us the left-handed version and they won't
>fit into the catalytic sites. Consequently there will be no breakdown of
>the sugar, no metabolism and no calories. So in theory the left-sugars
>could be used in baking to produce the same physical properties as sugar,
>but not the high calories.
>In theory, anyway. I'm not so sure it would interact in the same way with
>our taste buds, but I'm willing to reserve judgement.
>--
...not to mention the fact that just because _you_ can't digest it,
dosen't mean that the gas-producing bacteria in your gut can't.
Of course, it might be we can't smell left-handed farts so it would
be OK.
- Michael Chase
Ronald Sutcliffe
(David Smillie) writes:
>Yes, it is theoretically possible to use the left-handed form of sugar.
[rest deleted]
He is right, it is THEORETICALLY possible to use left-handed sugar.
However, it is much more difficult to make than normal sugar. Life on earth
has evolved around right-handed sugars and just about every green plant
makes them in some form or another. Left-handed sugars are virtually
unknown in nature for the same reason that they have no human usable
calories; there are no enzymes (plant) to make them. Therefore they would
have to be made in the laboratory. Just mixing glucose and fructose would
end up with a racemic mix of both right and left-handed sucrose. As anyone
who has had to separate and purify racemates can tell you, the process of
separation is a major hassle. So the production of L-sucrose in commercial
quantities would be very expensive, whereas R-sucrose is a simple matter of
purifying the extracts of sugarcane or sugarbeet. Someone might do it for a
specialty market (provided you can get it through the FDA), but it will cost
a bundle.
ÉÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍËÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ»
ºRonald Sutcliffe º ra...@bob.unt.eduº
ºCenter for Materials Characterization º voice: (817) 565-4359º
ºUniversity of North Texas º fax: (817) 565-4742º
ÌÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÊÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ͹
º"There is great chaos under heaven and the situation º
º is excellent." Mao º
º º
ÈÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍͼ
bob grochowski
>
>
>Some time back I remember hearing about left handed sugar. This was
(stuff deleted)
>Fact, fiction, or being kept off the market by the sugar producers?
I seem to remember the same description ... but it strikes me that the
idea occurred in a SF story. Probably an Asimov or Clark.
Provided as a possible pointer. (Frankly, I wish the stuff existed!)
RG
AE
Surely they are attuned to R-sucrose and will therefore not
be able to "taste" L-sucrose at all.
Seems rather pointless. You'll end up with this wonderful
calorie-free white granulated stuff that is completely tasteless.
Just use sand.
Andrew Earl
-- Many pages make thick book except for pocket --
-- bibles which are printed on very thin paper. --
Mike Beebe
: Some time back I remember hearing about left handed sugar. This was
: suppose to be an artificial substance with the same chemical structure
: as regular sugar except that the molecules were arranged on a left
: handed basis instead of a right handed basis. The nice thing about
: it was that it tasted and acted just like regular sugar except it
: could not be metabolised by the body and therefore had no calories.
: It was supposed to be the dieters dream.
: Fact, fiction, or being kept off the market by the sugar producers?
There is a company currently on this called Biotech and they are listed
on the American Stock Exchange.
Mike Beebe
Michael Moroney
> How do the sugar taste receptors in the mouth work?
> Surely they are attuned to R-sucrose and will therefore not
> be able to "taste" L-sucrose at all.
>
> Seems rather pointless. You'll end up with this wonderful
> calorie-free white granulated stuff that is completely tasteless.
They seem to react to more than that, since other sugars also taste
sweet (sometimes sweeter than sucrose), as do artificial sweetners
(though the halfway-decent ones are banned), even antifreeze, some
lead and beryllium salts are supposedly sweet (though I'm not about to
test any of them)
The secret is to find something that tastes sweet that does not have
calories, a horrible aftertaste or adverse health effects.
-Mike
t...@tms7808s.dukepower.com
1) It *IS* possible to manufacture "Left Handed Sugar".
2) It would be expensive to manufacture.
3) You would have to get FDA approval (add more money to #2).
This alone would discourage a company from manufacturing LHS for the
general public, but what about as a sugar substitute for diabetics?
(Not to mention that today's sugar substitutes taste like s**t) :-))
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> I DO NOT REPRESENT MY COMPANY <
Tom Swint t...@tms7808s.dukepower.com
"Time is just one damn thing after another"
-- Some guy on "Nova"
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Grant Edwards
: Some time back I remember hearing about left handed sugar. This was
: suppose to be an artificial substance with the same chemical structure
: as regular sugar except that the molecules were arranged on a left
: handed basis instead of a right handed basis. The nice thing about
: it was that it tasted and acted just like regular sugar except it
: could not be metabolised by the body and therefore had no calories.
: It was supposed to be the dieters dream.
: Fact, fiction, or being kept off the market by the sugar producers?
As I recall, its' true, but the stuff is difficult/expensive to
create. If you could genetically re-engineer some beets or cane or
corn or something to produce left-handed sugars, you would make so
much money that Bill Gates would be jealous.
--
Grant Edwards |Yow! Go on, EMOTE! I was
Rosemount Inc. |RAISED on thought balloons!!
|
gra...@rosemount.com |
Helge Hafting
> suppose to be an artificial substance with the same chemical structure
> as regular sugar except that the molecules were arranged on a left
> handed basis instead of a right handed basis. The nice thing about
> it was that it tasted and acted just like regular sugar except it
> could not be metabolised by the body and therefore had no calories.
> It was supposed to be the dieters dream.
>
> Fact, fiction, or being kept off the market by the sugar producers?
>
>
> David "fructose, glucose, sucrose, all the same to me" Adams
I am not sure it would be a good idea to eat this left handed sugar.
If L-sugar is able to get into the blood but isn't used up by your
cells, then you'll get very high levels of L-sugar in the blood. You could
get the same problems people with diabetes get when they eat too much
normal sugar.
Derek Tearne
>
>
>Some time back I remember hearing about left handed sugar. This was
>suppose to be an artificial substance with the same chemical structure
>as regular sugar except that the molecules were arranged on a left
>handed basis instead of a right handed basis. The nice thing about
>it was that it tasted and acted just like regular sugar except it
>could not be metabolised by the body and therefore had no calories.
>It was supposed to be the dieters dream.
>
>Fact, fiction, or being kept off the market by the sugar producers?
Fact, being kept off the market by free market forces, i.e. it's rather
expensive. Also Nutrasweat<tm> does the job pretty well and is metabolised
rather than passing through the body without doing anything.
As long as Nutrasweet can be produced more cheaply than Laevo rotary sugar
this stuff won't come onto the market.
>David "fructose, glucose, sucrose, all the same to me" Adams
You miss out the important one 'dextrose' which gives a clue to the
handedness of sugar. The vast majority of things we can digest are
dextro rotatary (right handed). This is because all manner of natural
enzymes are left-handed.
Why that situation came about in the first place is a mystery...
ObUL: The new sugar will almost certainly not be marketted under the name
sinistrose, although that would be my favourite.
Derek "Already sweet enough" Tearne
--
Derek Tearne. de...@nezsdc.fujitsu.co.nz Fujitsu New Zealand
Some of the more environmentally aware dinosaurs were worried about the
consequences of an accident with the new Iridium enriched fusion reactor.
"If it goes off only the cockroaches and mammals will survive..." they said.
David Smillie
The nice thing about using L-glucose, L-fructose, etc. is that you
could bake with it and it would occupy the same volume, and have the same
properties as the normal sugar. This would ensure that the resulting
product would have the same physical characteristics. Even if the sugar
didn't have any taste, it could be sweetened with aspartame so that the
volume:sweetness ratio was the same as sugar. Currently you can't simply
substitute one for the other as artifical sweeteners are much sweeter per
unit volume.
Sweet dreams....
--
______________________________________________________________________________
David Smillie Ancora imparo
Carleton University
If at first you don't succeed...destroy all evidence that you ever tried
______________________________________________________________________________
David DeLaney
>ve...@netcom.com (David Adams) writes:
>>David "fructose, glucose, sucrose, all the same to me" Adams
>You miss out the important one 'dextrose' which gives a clue to the
>handedness of sugar. The vast majority of things we can digest are
>dextro rotatary (right handed). This is because all manner of natural
>enzymes are left-handed.
>Why that situation came about in the first place is a mystery...
Not really; left-handed amino acids link up with other left-handed amino acids
just fine, as I recall, and right with right, but mixing the two results in
strained bonds, atoms trying to occupy the same space, crushed widgets,
etc. So all-left and all-right life make sense, but not really mixed-case.
Then it just comes down to symmetry breaking: the form of life that showed
up first and survived had all-left enzymes... Now "why left and not right"
*is* pretty much a mystery lost in the depths of history.
>ObUL: The new sugar will almost certainly not be marketted under the name
>sinistrose, although that would be my favourite.
>Derek "Already sweet enough" Tearne
ObUL: Alien life forms will automatically be digestible by space travelers,
and vice versa ("AAaiiiee! The Thing!")
Dave "although it may take a while after swallowing to detect the differences"
DeLaney
--
David DeLaney: d...@utkux.utcc.utk.edu; ObQuote: `I suggest quoting 'J"K"P' and
'J"RR"P' both. --K' Disclaimer: Opinions? UTK?? Me??? BWAAAAHahahahaa <choke>
<snort> hee hee; Thinking about this disclaimer (or about theor. particle __
physics) may cause headaches. Vicki and Paul and Ted and Alice. Kibo #: +1 \/
Randal R. Ketchem
>Not really; left-handed amino acids link up with other left-handed amino acids
>just fine, as I recall, and right with right, but mixing the two results in
>strained bonds, atoms trying to occupy the same space, crushed widgets,
>etc. So all-left and all-right life make sense, but not really mixed-case.
>Then it just comes down to symmetry breaking: the form of life that showed
>up first and survived had all-left enzymes... Now "why left and not right"
>*is* pretty much a mystery lost in the depths of history.
Left and Right handed amino acids link up perfectly fine. My Ph.D. project in
Biophysics just happens to be the determination of the structure of a peptide
(a short protein) that has alternating amino acid handedness. You can see
some results of this work, as well as a cool stereo image of the solved
structure, in the September 10th, 1993, issue of Science.
Randy
Randal R. Ketchem
Institute of Molecular Biophysics 904.644.7798 (voice)
Florida State University 904.644.8281 (FAX)
Tallahassee, FL 32306-3015 r...@magnet.fsu.edu (email)
David DeLaney
[and loses attributions to me in the process]
>>Not really; left-handed amino acids link up with other left-handed amino acids
>>just fine, as I recall, and right with right, but mixing the two results in
>>strained bonds, atoms trying to occupy the same space, crushed widgets,
>>etc. So all-left and all-right life make sense, but not really mixed-case.
>>Then it just comes down to symmetry breaking: the form of life that showed
>>up first and survived had all-left enzymes... Now "why left and not right"
>>*is* pretty much a mystery lost in the depths of history.
>Left and Right handed amino acids link up perfectly fine. My Ph.D. project in
>Biophysics just happens to be the determination of the structure of a peptide
>(a short protein) that has alternating amino acid handedness. You can see
>some results of this work, as well as a cool stereo image of the solved
>structure, in the September 10th, 1993, issue of Science.
Oookay; maybe I'm remembering that left- and right-handed versions of the
particular bases used in DNA don't go together nicely? I know I read
*something* along those lines... do alternating proteins have the same type
of tight spiral for the smallest structure (primary structure?)?
Dave "will *not* do OChem on the net for food" DeLaney
--
David DeLaney: d...@utkux.utcc.utk.edu; ObQuote: `I suggest quoting 'J"K"P' and
'J"RR"P' both. --K' Disclaimer: Opinions? UTK?? Me??? BWAAAAHahahahaa <choke>
<snort> hee hee; Thinking about this disclaimer (or about theor. particle __
physics) may cause headaches. Vicki and Paul and Terry and Alice. Kibo #: +1 \/
William G. Sinkins
>suppose to be an artificial substance with the same chemical structure
>as regular sugar except that the molecules were arranged on a left
>handed basis instead of a right handed basis. The nice thing about
>it was that it tasted and acted just like regular sugar except it
>could not be metabolised by the body and therefore had no calories.
>It was supposed to be the dieters dream.
>
>Fact, fiction, or being kept off the market by the sugar producers?
>
Ordinary sugar (sucrose) is a disaccharide made of d-glucose and d-fructose.
Sugar is cheap because is produced naturally by plant enzymes. "Left-handed"
sugar would be made of l-glucose and l-fructose. It isn't being kept off the
market because there is nothing to keep off. There is no natural source of
l-glucose or l-fructose (at least that I know of). Therefore they must be
synthesized in a lab. I just checked the catalogue of the Sigma Chemical Co.,
and they sell l-glucose for 30 bucks per gram. Under l-fructose it says
"inquire". If you have to ask ....
Unless someone can find a way to produce millions of tons of the stuff at
low cost, it'll remain a lab curiosity. As well it should, since we _need_
d-glucose, and there are several choices for dieters already.
Bill Sinkins
Grant Edwards
: As long as Nutrasweet can be produced more cheaply than Laevo rotary
: sugar this stuff won't come onto the market.
I'd gladly pay a premium for left handed sugar compared to Nutrasweet.
Even with aspertame, diet pop tastes awful. With left handed sugar, it
would taste the same as "real" pop, right?
Though in other stuff (pudding, etc) Nutrasweet is, IMHO, adequate.
OTOH, you can't bake w/ Nutrasweet. So there's a big market left open
for left-handed sugar.
: ObUL: The new sugar will almost certainly not be marketted under the
: name sinistrose, although that would be my favourite.
Good one! Sugar with no calories -- it does sound kind of sinful,
doesn't it.
--
Grant Edwards |Yow! I want to mail a
Rosemount Inc. |bronzed artichoke to
|Nicaragua!
gra...@rosemount.com |
Damian Conway
>ObUL: Alien life forms will automatically be digestible by space travelers,
> and vice versa ("AAaiiiee! The Thing!")
...but there's a fifty-fifty chance they'll be non-flattening :-)
damian
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
who: Damian Conway email: dam...@bruce.cs.monash.edu.au
where: Dept. Computer Science phone: +61-3-565-5184
Monash University fax: +61-3-565-5146
Clayton 3168 quote: "A pessimist is never disappointed."
AUSTRALIA
Damian Conway
> ObUL: Alien life forms will automatically be digestible by space travelers,
> and vice versa ("AAaiiiee! The Thing!")
To which I reply:
> But there's a fifty-fifty chance they'll be non-flattening.
^^^^^^^^^^^^^^
The punchline was, of course, supposed to be "non-fattening",
although "non-flattening" works well too :-)
wm...@vmsb.is.csupomona.edu
are able to metabolize it, then they will do so in your gut with resultant
gas and even more severe gastric distress. This is what happens with people
who are lactose intolerant, such as myself, the galactose in it will accumulate
in the intestines where the little bugs will go after it, with resultant severe
distress, gas and everything else. If you do not stop drinking milk, you will
keep the enzymes that change galactose into glucose, and you will not have to
suffer the heartbreak of lactose intolerance :-). These facts appeared in
Science some ten years ago, unfortunately I do not have the references.
Walter.
C.M. Yearsley
(in the UK) report that someone was trying to bring it to market -
this was a year or two ago now, and I forget where I saw it.
Since then there seems to have been no media coverage, except a
brief reference in a newspaper article to some other good idea that
didn't work out, saying that, like 'backwards' sugar, it seemed
to be carcinogenic.
I think this was in the 'Guardian' newspaper last year. Could it be true?
If it's just sugar, and isn't even digested, how could it be carcinogenic?
Chris
--
Chris Yearsley
c...@cs.keele.ac.uk
Philip L. Gravel
> I'd gladly pay a premium for left handed sugar compared to Nutrasweet.
> Even with aspertame, diet pop tastes awful. With left handed sugar, it
> would taste the same as "real" pop, right?
If left-handed sugar can't be recognized by the enzymes on our bodies, why
should it, then, have the sweet taste that we attribute to sucrose?? After
all, our taste buds are made up of the same building blocks as the rest of
our body. As someone pointed out earlier, lefthanded sugar may have all the
sweetness of a pile of sand.
Phil
-----
Philip L. Gravel Internet: pgr...@nap.amoco.com
Amoco Chemical Company, Chicago, IL Phone: (312)856-3553
----------
These opinions aren't worth the paper they're written on and
certainly don't reflect those of my employer.
danny burstein
quite possibly L-<sugars> would not be recognized as'sweet' by the tastebuds.
Just as an afterthought: a GREAT deal of the desirability of food comes
from the texture, smell, color, etc. rather than the actual taste. So in
this aspect, the use of L-sugars could be quite helpful.
For example, one common use of sugar is to coat french fries to make them
browner and crispier...
danny (who eats far too many french fries forfood)burstein
--
----------------------------------
Knowledge may be power, but communications is the key!
-dan...@panix.com (or dbur...@mcimail.com)
(10288) 0-700-864-3242
Unknown
>
> In article <1994Jan19.2...@rosevax.rosemount.com>,
> gra...@hydro.rosemount.com (Grant Edwards) writes:
>
> > I'd gladly pay a premium for left handed sugar compared to Nutrasweet.
> > Even with aspertame, diet pop tastes awful. With left handed sugar, it
> > would taste the same as "real" pop, right?
>
> If left-handed sugar can't be recognized by the enzymes on our bodies, why
> should it, then, have the sweet taste that we attribute to sucrose?? After
> all, our taste buds are made up of the same building blocks as the rest of
> our body. As someone pointed out earlier, lefthanded sugar may have all the
> sweetness of a pile of sand.
>
> Phil
>
I kept waiting for someone who works on this stuff to point it out, but
I guess I'm the only one listening who knows this.
Left handed sugar tastes exactly like right handed sugar, your tongue is
not as "Chiral" as your gut. The sweet receptors in your tongue can't
tell the difference between the two. Once in your gut left handed
sugar can't be digested as you don't have the right "handed" enzimes
(right handed as in correct).
Left handed sugar is produced by some plants (I have no idea which) but
it is extremely limited. Some micro-organizims can also eat left handed
sugar.
A friend of mine, who was getting a Ph.D. on the bugs that eat pinapples
in Hawaii, told me that the pinapple does product some of its sugars as
left handed, and that ants use some bugs as cattle to process the sugar
into something they can use. (similar to ants using aphids elsewhere).
This story was told to me quite a while ago so I can't vouch for my
memory or the details.
One note. Although left handed sugar will cook, burn, and taste exactly
like "real" sugar, it may not work in baking as the yeast may not be
able to eat it and make the bread/cake/whatever rise.
Hope this helps.
Darin Olson
Lockheed
Palo Alto
Philip L. Gravel
>In article <1994Jan20.2...@nap.amoco.com>, pgr...@nap.amoco.com (Philip L. Gravel) writes:
>>
>> If left-handed sugar can't be recognized by the enzymes on our bodies, why
>> should it, then, have the sweet taste that we attribute to sucrose?? After
>> all, our taste buds are made up of the same building blocks as the rest of
>> our body. As someone pointed out earlier, lefthanded sugar may have all the
>> sweetness of a pile of sand.
>>
>> Phil
>>
>
>I kept waiting for someone who works on this stuff to point it out, but
>I guess I'm the only one listening who knows this.
>
>Left handed sugar tastes exactly like right handed sugar, your tongue is
>not as "Chiral" as your gut. The sweet receptors in your tongue can't
>tell the difference between the two. Once in your gut left handed
>sugar can't be digested as you don't have the right "handed" enzimes
>(right handed as in correct).
If you have documentation to back this statement up, I'd like to have
references. Whether something tastes sweet or not has to do with how the
taste buds function. While the tongue itself is not "chrial", the proteins
that make up the receptors sites certainly. If the tongue tell the difference
between right-handed sucrose, glucose, and fructose, why shouldn't it be able
to tell the difference between right- and left-handed sucrose????
Steve Glover
hydrophobicity/hydrophilicity to select whether or not a molecule triggers
them or not, I can quite categorically confirm that 'mirror' sugar will
taste NOTHING like 'real world' sugar. True, it won't be metabolised as
easily (but if it can be metabolised it will have EXACTLY the same number
of calories/gram -- this depends on chemical bonding, not shape), but it
is likely to have an osmotic effect (old medic/chemist joke: putting a
non-digestible sugar in a punchbowl... the effects are rather akin to 14
pints of guinness and a large curry).
In short, 'mirror sugar' is an urban legend, and even if it did exist,
it'd have the opposite effect to that intended.
[Background: I am a chemist who has worked in the pharmaceutical and
carbohydrate fields for more years than I care to think about]
*******************************************************************************
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(*@|||@*) Talk (Fan programme, Intersection: 1995 Worldcon)
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\\|||// Market (\/ )
Lisa Dusseault
> In article <vera2CJ...@netcom.com> ve...@netcom.com (David Adams) writes:
> >Fact, fiction, or being kept off the market by the sugar producers?
> >
> low cost, it'll remain a lab curiosity. As well it should, since we _need_
> d-glucose, and there are several choices for dieters already.
>
> Bill Sinkins
>
>
artificial sweeteners was to lower the body's blood sugar level. When
the sweet taste is in the mouth, the taste buds think it's sugar and
send the message to metabolize some sugar, because more is on the way.
That would explain all those people I know who seem to be hooked on diet
sodas: one drink lowers your blood sugar enough so that you crave more
sugar, and to satisfy the craving for sweetness they drink another can...
(I know, I was hooked one summer. I've sworn off artificial sweeteners
since I heard about this.)
Is this indeed what happens? This would be dangerous to people with
metabolic disorders such as hypoglycemia or diabetes, right?
John Eric Sanders
>I was told that the body's reaction to Nutrasweet(tm) and other
>artificial sweeteners was to lower the body's blood sugar level. When
>the sweet taste is in the mouth, the taste buds think it's sugar and
>send the message to metabolize some sugar, because more is on the way.
>That would explain all those people I know who seem to be hooked on diet
>sodas: one drink lowers your blood sugar enough so that you crave more
>sugar, and to satisfy the craving for sweetness they drink another can...
>(I know, I was hooked one summer. I've sworn off artificial sweeteners
>since I heard about this.)
>
>Is this indeed what happens? This would be dangerous to people with
>metabolic disorders such as hypoglycemia or diabetes, right?
Even if this is what happens, it isn't dangerous to diabetics. In
diabetics (well, insulin-dependant diabetics), the body doesn't produce
the insulin to metabolize sugar, so getting a message "to metabolize
some sugar, because more is on the way," will do nothing.
I'm diabetic, and I don't see how I could survive without nutrasweet.
-----------------------------------------
jsan...@sun.sws.uiuc.edu There is a method to my madness, but more
often it is madness to my method.
Of course, I speak for nobody--sometimes not even for myself.
Andrew Lewis Tepper
Sugar by
> it is extremely limited. Some micro-organizims can also eat left handed
> sugar.
>
algaes(sp?). That's it. I carefully investigated this a year ago in
response to a thread I started on rec.cooking. I finally tracked down a
(the?) scientist who had done research on LH sugars. They are available
for sale, price for LH glucose was ~$10/gram. He confirmed that they do
taste sweet, but not as sweet as RH sugars. Furthermore, glucose is one
of the least sweet sugars. They also had a few other LH sugars for sale,
also very expensive, and ones I've never heard of. They do not know if
LH sugars are safe to consume, and also don't know if they are digested
or not. I can try to locate the company and scientist I talked to if
anyone wants to pursue it.
Andy
Bob Bridges
(nor, for that matter, heard from anyone who has)). I can understand why
the body might not metabolize left-handed sugar. But if the body is
prepared to handle only right-handed sugar, why would left-handed sugar
taste sweet?
------------------------------
"My husband doesn't believe in gossip, and you can tell him I said so."
bu...@qedbbs.com (Bob Bridges) or qed!bubba
The QED BBS -- (310)420-9327
gc
When you say that a molecule has a handedness, that means there is at
least one chiral center--an atom about which the molecule isn't symmetric.
Anything, such as an enzyme, which binds this molecule such that it is
interacting with, or specifically not interacting with, atoms around
the chiral center will be sensitive to the handedness of the molecule.
It is entirely possible for other proteins to be interacting with
atoms away from the chiral center such that it cannot see the
handedness of the molecule.
With this in mind, we know that enzymes which bind sugar during
metabolism bind pretty much the whole thing and thus prefer one
enantiomer over the other. I don't think that it's known what part
of a molecule is recognized when we taste something as sweet, but I
wouldn't be surprised if it was just the hydroxyl group plus a bit
extra, all of which is far from the chiral center.
--
--g (I'm a mixture of both right- and left-handed forms) c
Sean Willard
: In article <ePV8gc...@qedbbs.com>, bu...@qedbbs.com (Bob Bridges) wrote:
: > [...] But if the body is
: > prepared to handle only right-handed sugar, why would left-handed sugar
: > taste sweet?
: >
: [...] I don't think that it's known what part
: of a molecule is recognized when we taste something as sweet, but I
: wouldn't be surprised if it was just the hydroxyl group plus a bit
: extra, all of which is far from the chiral center.
Actually, it *is* known. If I remember right (speaking as a complete
non-chemist/non-biologist), sweetness is determined by the spacing of
two hydrogen atoms hanging off a sugar molecule.
Oddly enough, the receptor for this in a taste-bud seems to not have
*quite* the same spacing, with the result that certain other molecules
like saccharin actually fit *better*, hence are sweeter-tasting by
orders of magnitude than, say, glucose. "Odd" because there are other
cases where evolution did a damn fine job, like the way the eye's
frequency response peaks (in the yellow) at right about the same
frequency of light that the sun's output peaks at. A hint that we
evolved in this solar system rather than, say, Sirius'.
Sean
-------------------------------------------------------------------
Sean Willard Internet: se...@panofsky.desy.de
U.C. Davis / H1 - F22 DECnet: VXDESY::WILLARD
Bldg. 2g, rm. 10 tel. 2091 DSYIBM: H01WIL
John Woods
"Odd" because there are other cases where evolution did a damn fine
job, like the way the eye's frequency response peaks (in the yellow)
at right about the same frequency of light that the sun's output peaks
at. A hint that we evolved in this solar system rather than, say,
Sirius'.
Let's not forgot that evolution got the retina the wrong way round,
however! (in some cases).
... John Woods
--
"
Forsan et haec olim meminisse iuvabit (Virgil)
[approx] Tr: The time may come when we will look back on these days and laugh
"
Tristan B. Davies
>
>Let's not forgot that evolution got the retina the wrong way round,
>however! (in some cases).
John--
Do you mean it's the wrong way around because the photoreceptors are at
the "back," so light travels through the other layers first? If so,
I've got a reason (maybe not evolutionarily correct, but a reason
nonetheless...)
Tristan
--
/\//\\/\\//\//\\/\\//\//\\/\\//\//\\/\\//\//\\/\\//\//\\/\\//\//\\/\\//\//\\/\
tristan davies ........... t...@med.unc.edu ........... wtvd newschannel eleven
"It was all sex, scandal, brutal crime, sports, uh, children with incurable
diseases, and lost puppies." -- Paddy Chayevsky, "Network"
Sean Willard
: In article <CL1wq...@festival.ed.ac.uk> ean...@castle.ed.ac.uk (John Woods) writes:
: >
: >Let's not forgot that evolution got the retina the wrong way round,
: >however! (in some cases).
: John--
: Do you mean it's the wrong way around because the photoreceptors are at
: the "back," so light travels through the other layers first? If so,
: I've got a reason (maybe not evolutionarily correct, but a reason
: nonetheless...)
: Tristan
Let's hear your reason, Tristan. I assumed John meant the usual
image-inversion.
Paul Savage
writes:
>Actually, it *is* known. If I remember right (speaking as a complete
>non-chemist/non-biologist), sweetness is determined by the spacing of
>two hydrogen atoms hanging off a sugar molecule.
>
>Oddly enough, the receptor for this in a taste-bud seems to not have
>*quite* the same spacing, with the result that certain other molecules
>like saccharin actually fit *better*, hence are sweeter-tasting by
>orders of magnitude than, say, glucose.
What's more there are other molecules which are *several* orders of
magnitude sweeter than sugar (from memory the best are around 200,000 times
sweeter). These molecules were designed to fit the "sweetness receptor" of
which much is known.
I read somewhere that one of the newest artificial sweeteners (which has not
yet come to the market) is so sweet that it's actually cheaper to
manufacture than sugar on an equal sweetness basis. Now given that sugar is
a commodity product that sells for about 20 cents per pound this stuff must
be pretty effective.
Paul.
--
paul....@mercury.chem.csiro.au -- Australian Science...Australia's Future
It's not enough to succeed. Others must fail. --Gore Vidal c.1925
gc
<pa...@mercury.chem.csiro.au> wrote:
> In article <CL08t...@dscomsa.desy.de> Sean Willard, se...@galileo.desy.de
> writes:
> >Actually, it *is* known. If I remember right (speaking as a complete
> >non-chemist/non-biologist), sweetness is determined by the spacing of
> >two hydrogen atoms hanging off a sugar molecule.
> >
> >Oddly enough, the receptor for this in a taste-bud seems to not have
> >*quite* the same spacing, with the result that certain other molecules
> >like saccharin actually fit *better*, hence are sweeter-tasting by
> >orders of magnitude than, say, glucose.
>
> What's more there are other molecules which are *several* orders of
> magnitude sweeter than sugar (from memory the best are around 200,000 times
> sweeter). These molecules were designed to fit the "sweetness receptor" of
^^^^^^^^^^^^^^^^^^^^^^^^
> which much is known.
^^^^^^^^^^^^^^^^^^^
Actually, of which virtually nothing is known.
But, yes, the 200,000x is about right. The sweetest substance known is
actually a protein found in the berries of a tree that grows in parts of
Africa. Although the protein is being extensively studied, the thing
about it which makes it so sweet is still unknown.
--
--g (only 3.5 times sweeter than an equimolar solution of sucrose) c