Obtaining Chiral Sugar Samples

[scifriend]

I was interested in a doing a chemistry/biology project that compares how bacteria interact with L- and D- forms of sugars.

I planned to use L-glucose and D-glucose (or tagatose or fructose), but I found that these chemicals are very expensive. Even 50mg of some L-sugars cost hundreds of dollars.
I also don't think that I have the right precision of lab equipment or the skill to be able to work with very small quantities.

How hard is it to make sugars?
Or is there any other way to get 'small' amounts (~25g) of these for less than $100? Or maybe sugars of lesser purity?

I'm trying to evaluate if I should select a different topic to work on.
Thanks

[deleted-141593]

Hi there,

This is an interesting idea, but as you said, L-glucose is very expensive. This is a good reddit thread on why that is here: http://www.reddit.com/r/askscience/comm ... _pound_as/

Do you have any idea how much you would need?

The cheapest I found was this list of Chinese sources of unknown reliability: http://the.animalztube.com/product-tag/tagatose.html

Cheers,
Colin

[scifriend]

Hi Colin,

One comment from the reddit thread is:
"Synthesizing a racemic mixture of glucose isn't terribly difficult" -- that actually would fit into the experiment I have in mind.
But I can't find anywhere where that is sold either.
I did see that one company tried to market L-glucose as a laxative -- I would have thought that if there is an application for it like that that it would be more readily available.

The Chinese site is interesting. But glucose prices are expensive and minimum purchase amount is large.

Thanks.

[deleted-141593]

I found D/L Glucose (racemic mixture), but it's still seriously expensive: http://www.molbase.com/en/name-D,L-glucose.html
I wish I could be of more help. You could try contacting Sigma Aldrich or Fisher Sci to see if they have some low grade stuff or racemic mixtures. Tell them it's for a student project. It might work.

http://www.sigmaaldrich.com/technical-service-home.html

http://www.fishersci.com/ecomm/servlet/ ... ig=contact

Keep me posted,
Colin

[deleted-132180]

Hi there,

Interesting idea for a science project. What kind of "interactions" are you looking for? Are you seeing if L- or D-forms of sugars have different antimicrobial effects on the bacteria, or how well the bacteria metabolize the different forms of sugars? What will your experimental readout be? Just some questions to keep in mind as you start planning your experiments!

The previous expert already gave you some good advice. I agree that it is a good idea to perhaps try contacting Sigma Aldrich or Fisher Sci, tell them a little bit about your project and what you would like to do, and see if they are able to offer you a discount for the sugars. Another idea is to look up chemistry or biochemistry labs at local universities and see if they can spare you some reagents or perhaps help you with synthesizing the racemic mixture. Many people are happy to help a student out with their science projects, so you never know what you may find! I would also suggest posting in the physical science thread on Science Buddies as well to see if there are any chemists there who have the expertise to answer your questions about where to get the reagents or how to make them easily.

Good luck!

Connie

[scifriend]

Hi Connie,

Thank you for the encouragement.
The idea for the experiment is to see how well bacteria can metabolize different forms of sugars.
I will try contacting the companies that Colin suggested.

Thanks

[deleted-141593]

Hi there,

Any luck with this? Just checking in to see if you need any help.

Cheers,
Colin

[scifriend]

No. I did ask the chemical companies, but only received quotes for many hundreds of dollars for very small quantities.

Thanks for asking.

[deleted-141593]

Did you develop a different project idea instead?