Investigating inhibition of dopa oxidase activity SSERC protocol

Fern

Has anyone used the SSERC protocol on investigating inhibition of dopa oxidase activity. Where is the best place to purchase L-dopa for this experiment please?

FlaskHead

Hi Fern, try searching for it using its systematic name - L-3,4-dihydroxyphenylalanine.

Goaty_McGoatface

The SSERC document I’m looking at quotes Sigma Aldrich as a potential supplier. It was £31.20 for 5 g whenever the SSERC document was written (sometime around 2016).

You won’t need a lot so 5 g will last you. Last year, we had two students using it for AH Biology projects and in total used about 0.2 g. Enough to make about 100 mL of 10mM L-Dopa.

FlaskHead

I had a look on Sigma Aldrich and it’s £58 for 5g.

https://www.sigmaaldrich.com/GB/en/product/sigma/d9628

Goaty_McGoatface

Just found this PDF from Mystrica (link below).

http://www.mystrica.com/Pages/Enzymes/dopaoxidase.pdf

Turns out L-Dopa is sold as a dietary supplement. They advise looking for L-Dopa extracts advertised as 98% pure or higher as it gave results that were equivalent to pure L-Dopa and it’s cheaper.

https://www.british-supplements.net/products/mucuna-extract-ldopa-supplement?srsltid=AfmBOoqcoxtG9nGqOgFhH8EBgN25nZrtg4ok1vz0rVtIfMvK7l3GtbZV&variant=28740803854410

From the supplement linked above, 353 mg of L-Dopa per capsule and 30 capsules in a pack so 10,590 mg of L-Dopa in total. 10.5 g of L-Dopa for about £15 is a no brainer compared to the almost 60 quid for less than half of that from Sigma Aldrich.

Fern

Thank you. I had a look at Sigmaaldrich and Thermofisher and both were quite costly, especially once the carriage charges were added. I did come across the Mystrica instructions yesterday so we have indeed decided to try one of the Mucuna bean/L-dopa dietary supplements. Will let you know how it works.

Goaty_McGoatface

Fern look forward to hearing how it goes. This is a good opportunity for you to become a pioneer 😉

Fern

A bit late in posting but I tried this experiment using a L-dopa supplement (which was actually 50% L-dopa and making it up to 10mmol/l) and it seemed to give the expected results/trend. I don’t know how the results compare to using pure L-dopa but it worked well enough for the class experiment.