effect of pH on an enzyme reaction - what type of amylase is best?

I need to order some amylase to be used in a practical to look at the the effect of pH on an enzyme reaction.
When I set up for this practical i used some bacterial alpha amylase solution - i simply used this as it was already in the prep room (i am new to the role) and diluted it down. But is this the best type of amylase to use for this practical? Looking at the catalogue to reorder I can see various forms of alpha amylase and wasn't sure which to get.
does it affect the practical if it contains reducing sugars?
I would be grateful for your advice
 
:):)
I need to order some amylase to be used in a practical to look at the the effect of pH on an enzyme reaction.
When I set up for this practical i used some bacterial alpha amylase solution - i simply used this as it was already in the prep room (i am new to the role) and diluted it down. But is this the best type of amylase to use for this practical? Looking at the catalogue to reorder I can see various forms of alpha amylase and wasn't sure which to get.
does it affect the practical if it contains reducing sugars?
I would be grateful for your advice
Diastase Lisa. happy New Year!
 

ChrisN

Jack of all trades master of several.
This is what the society of biology have to say

http://www.nuffieldfoundation.org/practical-biology/investigating-effect-ph-amylase-activity
1 Amylase (See CLEAPSS Hazcard and Recipe card) The powdered enzyme is HARMFUL, but solutions less than 1% are LOW HAZARD. It is wise to test, well in advance, the activity of the stored enzyme at its usual working concentration to check that substrates are broken down at an appropriate rate. Enzymes may degrade in storage and this allows time to adjust concentrations or to obtain fresh stocks. Amylase will slowly lose activity, so it is best to make up a fresh batch for each lesson; batches may vary in activity and results collected on different days will not be comparable. The optimum temperature for your enzyme will be listed on the supplier’s label.
Using saliva: the CLEAPSS Laboratory Handbook provides guidance on precautions to take (including hygiene precautions) in order to use saliva safely as a source of amylase. This has the advantage of being cheaper, not requiring technicians to make up fresh solutions each lesson, it is directly interesting to students, and salivary amylase is reliable. It also provides an opportunity to teach good hygiene precautions – including ensuring that students use only their own saliva samples (provide small beakers to spit into); that students are responsible for rinsing their own equipment; and that all contaminated glassware is placed in a bowl or bucket of sodium chlorate(I) before technicians wash up.

Basically Amylase is a Pain and they are far better off spitting in it. Or as George says use Diastase.

ChrisN
 
This is what the society of biology have to say

http://www.nuffieldfoundation.org/practical-biology/investigating-effect-ph-amylase-activity



Basically Amylase is a Pain and they are far better off spitting in it. Or as George says use Diastase.

ChrisN

Agree with Chris
We use saliva (as per CLEAPSS) for pH and amylase practicals as none of the manufactured ones work at the correct pH. If we are just using it for the model gut experiment we use the bought in stuff. :)
 
Agree with Chris
We use saliva (as per CLEAPSS) for pH and amylase practicals as none of the manufactured ones work at the correct pH. If we are just using it for the model gut experiment we use the bought in stuff. :)
:eek::eek::eek:..... Hi Sharon. Nothing wrong with this apart from the fact that I wouldn't be comfortable moping up buckets of saliva. Happy New Year Sharon!:D:D:D
 
I make it a strict rule that if pupils using saliva then they must clean their own glassware. Teachers usually decide that they can't possibly ask them to do this so they conclude that it's not so important that the amylase doesn't work at the correct pH after all. So it doesn't really matter which amylase you buy.
The amylase with reducing sugars in it is a pain if you're doing the visking tubing expt - as it messes up the glucose testing part - on the other hand that never works well either!
 
I make it a strict rule that if pupils using saliva then they must clean their own glassware. Teachers usually decide that they can't possibly ask them to do this so they conclude that it's not so important that the amylase doesn't work at the correct pH after all. So it doesn't really matter which amylase you buy.
The amylase with reducing sugars in it is a pain if you're doing the visking tubing expt - as it messes up the glucose testing part - on the other hand that never works well either!
Happy New Year Carine.:) Good Points to add. Fungal amylases have reducing sugars. Having used all I can say that Diastase is the most reliable amylase.:);)
 
I make it a strict rule that if pupils using saliva then they must clean their own glassware. Teachers usually decide that they can't possibly ask them to do this so they conclude that it's not so important that the amylase doesn't work at the correct pH after all. So it doesn't really matter which amylase you buy.
The amylase with reducing sugars in it is a pain if you're doing the visking tubing expt - as it messes up the glucose testing part - on the other hand that never works well either!

we do a fake demo for the visking tubing thing - 1% glucose inside and outside the tubing so the benedicts test works. and the teacher sets another one up (with fake amylase) to show them how it was set up.....as there is nothing to really see it doesnt matter.....never done it as an expt for the kids......
 
we do a fake demo for the visking tubing thing - 1% glucose inside and outside the tubing so the benedicts test works. and the teacher sets another one up (with fake amylase) to show them how it was set up.....as there is nothing to really see it doesnt matter.....never done it as an expt for the kids......
:eek: A "fake Demo" Claire? Are we talking about a "Tech Cheat"? I thought that "Tech Cheat" was an Urban myth.:D:D:D Has anyone else have any excellent "Tech Cheats" in their repertoire?
 

Carol Taylor

Footsore
One chemistry teacher insists that I surreptitiously add tiny pieces of copper to the copper oxide and carbon in the crucibles after pupils have heated them to prove that copper is produced!!! It actually always is produced but she still likes them to see shiny metal!!!!!!!!
 
Thanks for all your responses! The teachers do already use saliva for looking at digestion of starch but in the new AQA required practicals it says to use a 1% solution of amylase to look at the effects of pH on the rate of enzyme reaction.
Will perhaps have a go with some diastase. ;)
 
Thanks for all your responses! The teachers do already use saliva for looking at digestion of starch but in the new AQA required practicals it says to use a 1% solution of amylase to look at the effects of pH on the rate of enzyme reaction.
Will perhaps have a go with some diastase. ;)

AQA (and I presume all of the other examining bodies) have provided a list of examples of required practicals, but the key thing is that the practical work covers the particular skill and use of equipment. Schools are allowed to adapt the practicals to suit their own equipment provided that the students still learn the same thing. Taken from the AQA practicals website:
("Please note: it is the Apparatus and Techniques requirements which are compulsory and must be fulfilled. Teachers are encouraged to adapt or develop activities, resources and contexts to suit their equipment and provide the appropriate level of engagement and challenge for their own students".)
In this case the source of the amylase (i.e. saliva or bought in) doesn't matter, so if you currently use saliva and it works then I would just tweak the method of the new practical to include your previous procedures.
 
One chemistry teacher insists that I surreptitiously add tiny pieces of copper to the copper oxide and carbon in the crucibles after pupils have heated them to prove that copper is produced!!! It actually always is produced but she still likes them to see shiny metal!!!!!!!!
:eek::eek::eek: Oh Dear, Carol. Shiny copper metal formed? Well Technicians do have "Tech Cheats" at hand if things go pear shaped. However I think that we must coin a new phrase -"Teacher Cheat".:D:D:D Happy New Year!
 

Julie Delaney

COMMITTEE
:eek: A "fake Demo" Claire? Are we talking about a "Tech Cheat"? I thought that "Tech Cheat" was an Urban myth.:D:D:D Has anyone else have any excellent "Tech Cheats" in their repertoire?
I make "bromine" out of glycerol and iodine in a sealed vial to show the kids. We also blow balloons up over test tubes to show that yeast has produced CO2. There's probably a whole lot more! :eek: :D
 
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