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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: RoseZ on February 19, 2014, 09:30:24 AM

Title: trouble with enzyme kit for sucrose, glucose, and fructose
Post by: RoseZ on February 19, 2014, 09:30:24 AM
Hi,

I am having trouble with the Megazyme kit (K-SUFRG) for sucrose, glucose, fructose.  The kit is specific for gluctose and fructose, but sucrose is not measured independently.  The response for glucose (ΔAgluc) is subtracted from the response for sucrose (ΔA total glucose) and this is resulting in low and even negative values for sucrose.  I am trying to measure gluc, fruc, suc in sweet potato extracts and sucrose is expected to be the predominant sugar.  But my values for sucrose are usually lower than fructose and glucose.

Is anyone familiar with this kit?  Please help.

Thank you,
Rose
Title: Re: trouble with enzyme kit for sucrose, glucose, and fructose
Post by: Babcock_Hall on February 19, 2014, 09:59:31 AM
I am not familiar with this kit.  Would you provide some more details?  The method of analysis and the equations would help.
Title: Re: trouble with enzyme kit for sucrose, glucose, and fructose
Post by: RoseZ on February 19, 2014, 11:40:24 AM
Thanks for your reply.  Yes, I will give more information.  Rather than type everything out, here is a link to the booklet for the kit which explains all of the reactions.  http://secure.megazyme.com/files/BOOKLET/K-SUFRG_1212_DATA.pdf

I have sweet potato samples that have been freeze-dried and then ground to a fine powder.  The sweet potato flour is then extracted with water (~35mg powder to 1mL water).  This extract is used then with the kit directly.  The directions in the booklet are for using a spec, but I have scaled down everything 10-fold for use with a plate reader.

Thanks,
Rose
Title: Re: trouble with enzyme kit for sucrose, glucose, and fructose
Post by: Babcock_Hall on February 19, 2014, 01:19:25 PM
I am a little bit behind at work, but I will respond as soon as I can.