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hector2000
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Quote: Originally posted by Sauron  | Read the patent
Benzaldehyde (106 mg, 1 mmol),
petroleum ether (80 ml),
ethanol (0.5 ml),
baker's yeast (5 g)
and the pyruvic acid buffer (5 ml)
were stirred at 50° C. for 24 h.
That is a little over 90 ml total so figure `100 ml and that gets you just 30 mg L-PAC
Times 3333 = 333 liters. Use a 350 L stirred bioreactor regulated to 50 C. That gets you 100 g if you do everything right.
You have a LOT to learn about biotech.
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two point is important here
first:in this scale(patent scale)this is not very important that how much ether you use because 60 ml ether is little and really i
think ether will not do important work then for 100gram l-pac we can use little amount like 2.5lit because ether in this reaction is solvent no more(i
think)
second:i think yeast will grow up(like ferment suger to alcohol) then we can use smaller amount but making l-pac proccess will take
more time(again i think)
also i think biggest problem is making pyruvic acid anyone has complete route for making pyruvic acid?
[Edited on 26-4-2009 by hector2000]
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Nicodem
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| Quote: Originally posted by hector2000 |
second:i think yeast will grow up(like ferment suger to alcohol) then we can use smaller amount but making l-pac proccess will take
more time(again i think)
also i think biggest problem is making pyruvic acid anyone has complete route for making pyruvic acid? |
Yeast will grow up at 50°C? Yeah right, it sounds like a perfect temperature for multiplication. What is good for enzymes is not necessarily good for
reproduction!
Pyruvic acid is available at any chemical supplier.
This thread is of terrible quality. hector2000, how about if you first read some literature, like all the reviews, papers and patents posted in the
old thread? Just clicking to the reply button without investing any thought whatsoever will only result in another multipage thread without any
relevant content.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Elena
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| Quote: Originally posted by panziandi | | Using a 25L bioreactor you should in theory get approx 7g product but I shall let you do the math for that one yourself![Edited on 26-4-2009 by
panziandi] |
As soon, as it not for commercial purpose, and it is only to get satisfaction on successful
experiment, yielding amount of 7 g could make him happy too.
Isn't it gentlemen?
[Edited on 26-4-2009 by Elena]
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Paddywhacker
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I do believe that the solvents in the bioreactor will break the yeast cell membranes, making the reaction a crude cell-free extract reaction. The
insoluble cell fragments will still be there, and that is what I suspect the workup refers to as "yeast".
Certainly, there will be no yeast growth at 50 Celcius.
I would always think that starting with actively growing yeast rather than commercial yeastcake would give better enzymatic activity, but I could
easily be mistaken.
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hector2000
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if we accept ratio of this patent then india and china should use 3000lit container for make 1kg l-pac?
i search and found that india and china make l-pac(they should use huge amount of ethanol-water..)
unfortunately pyruvic acid here is very expensive.may someone explain method of making pyruvic acid?
[Edited on 26-4-2009 by hector2000]
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panziandi
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There will be no cell growth of yeast at 50*C! This is not a microbial fermentation! This is an enzymatically catalysed reaction. The patent states
that purified enzymes are terribly expensive, whereas yeast are cheap and do the job themselves!
@ Elena: I don't think hector would be satisfied with only 7g of l-PAC ...?
The quantity of yeast is just under 17kg (from the scale-up calculations). You will need more than 2.5L of Petroleum or else you will have a horrible
thick paste (I'm speculating but i can picture this horrid paste!). Indeed cell lysis is going to occur releasing the enzymes that are required for
the reaction.
I'm sure anyone who has been reading this thread has thought (as I have) how you could potentially better the patent method, however I am not going to
divulge my ideas. I think you should be able to show some sort of problem solving skills yourself.
Pyruvic acid I think I already gave you some ideas for making:
CH3-CHOH-CH2OH + [O] => CH3-CO-COOH
or
CH3CHOH-COOH + [O] => CH3-CO-COOH
or
CH3-COCl + CN- => CH3-COCN
CH3-COCN => CH3-CO-COOH (hydrolysis of nitrile)
They are your 3 options... unless you fancy preparing pyruvic acid in a biotech fashion too...
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hector2000
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| Quote: Originally posted by panziandi | There will be no cell growth of yeast at 50*C! This is not a microbial fermentation! This is an enzymatically catalysed reaction. The patent states
that purified enzymes are terribly expensive, whereas yeast are cheap and do the job themselves!
@ Elena: I don't think hector would be satisfied with only 7g of l-PAC ...?
The quantity of yeast is just under 17kg (from the scale-up calculations). You will need more than 2.5L of Petroleum or else you will have a horrible
thick paste (I'm speculating but i can picture this horrid paste!). Indeed cell lysis is going to occur releasing the enzymes that are required for
the reaction.
I'm sure anyone who has been reading this thread has thought (as I have) how you could potentially better the patent method, however I am not going to
divulge my ideas. I think you should be able to show some sort of problem solving skills yourself.
Pyruvic acid I think I already gave you some ideas for making:
CH3-CHOH-CH2OH + [O] => CH3-CO-COOH
or
CH3CHOH-COOH + [O] => CH3-CO-COOH
or
CH3-COCl + CN- => CH3-COCN
CH3-COCN => CH3-CO-COOH (hydrolysis of nitrile)
They are your 3 options... unless you fancy preparing pyruvic acid in a biotech fashion too... |
Yes before you say these method for making pyruvic acid but problem is ratio and temp and separation , ... and it need more detail.
Really iam confuse because for making 100gram of l-pac i should buy 300lit container with stirrer and about 240lit ether and lot of ethanol.if you
calculate the price it should be around 1000-2000$ just for 100gram of l-pac.
i search here and speak with company that make Pseudoephedrine with l-pac and make l-pac with Ferment method.this company sale 1kg pseudoephedrine
just 70$.
Sure there is better and cheaper instruction for making l-pac
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panziandi
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There likely is! I can think of a few cost cutting routes, if you sat down and thought about it I'm sure you could too! But THIS method you found a
patent for does NOT use a fermentation... It uses a crude enzyme extract! It is not ether that is used, it is petroleum ether (petrol) that is used,
ether (diethyl ether) is used to wash the yeast AFTER the reaction, and the petroleum and the ether is distilled off in vacuum to leave the product.
I could have, and I think I did hint at the economics of this, that it would be EXPENSIVE. Thankfully the penny has dropped for you too!
My methods for pyruvic acid are simple and common procedures I have adopted for pyruvic acid, calulate your own stoichometry! Go look up Orgsyn method
they list a method for obtaining pyruvic acid from tartaric acid. They also list a method for obtaining ethyl pyruvate from lactate which could be
adopted to go form lactic acid to pyruvic acid. Do your own research it isn't too difficult (literature searches are fundamental abilities for anyone
in the science community!!)
I think this biotech method really sucks to be honest and I think you'd be better off buying l_PAC or using a chemical method!
[Edited on 26-4-2009 by panziandi]
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hector2000
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My Friend i should pay money for know your method?(how much)
before i think here every thing(teaching and learning)is free but doesnt matter i believe you spent yor time for find you method and maybe that method
wasnt free for you.
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DJF90
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Hector. Your signature is "Chemistry=Chem+ is+ Try", yet you dont seem to be trying... For lab scale production the easiest method would be a chemical
one. Please dont ask how, go an research it for yourself. If you cannot do your own research then you have little hope of being able to do the
procedure.
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panziandi
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Biotech is great for producing chiral compounds like l-PAC in that you have very high chiral-yield but unfortunently actual chemical yield is not
always very great.
My ideas are exactly that... ideas. Ideas of how to better a scale-up of the patent. I'm not selling them since I have not got the time nor equipment
to actually see if these ideas would better the reaction. Why don't you sit down, have a think about it and post some ideas of how you propose to
better the reaction and then people could comment and offer advice. People are not going to spoon-feed you.
You already suggested reducing the volume of petroleum ether to 2.5L, I can assure you taht that would result in something like marmite! But you are
along the right lines, you likely will not require 270L but you will require more than 2.5L... go figure some other varibales to potentially better
the reaction and read some texts and get ideas down then present them for constructive criticism from people on the forum, otherwise people will feel
like they are doing all the work for you and not getting anything in return, and you will end up looking lazy and having a bad reputation!
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Sauron
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This is a replay of hector's demeanor in the AA thread.
Naked wholesale demand for spoonfeeding
REeagents always too expensive
Not the slightest understanding of basics
And no attempt at self-help whatsoever.
UTFSE or Google for pyruvix acid's preps.
Organikum posted extensively on this
Solo ALREADY told you that, hector.
OBVIOUSLY you ought to go after a conventional route to racemic PAC and then resolve rge L-PAC the old way.
You have not told your purpose in making L-PAC.
Inquirinf minds want to know.
The Indians pharm industry are the main producers of L-PAC and mostly it is used in making l-psuedoephedrine ("sudafed"). However I really doubt that
yoiu want to make nasal decongestant.
[Edited on 27-4-2009 by Sauron]
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chemrox
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How about kicking this one over to Detritus? Nothing worthwhile has been exchanged.
[Edited on 27-4-2009 by chemrox]
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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Nicodem
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I give this thread another 24 hours. After that time, I'm going to close it since the original poster promotes nothing but extreme laziness. Asking
questions that were already answered in the old thread is ridiculous! Claiming of wanting to start a large scale process and not bothering to search
and read the scientific and patent literature is stupid. Continuously asking to be spoon fed is a waste of time for the helpful members. This thread
is heading toward the same type of crap as seen in the acetic anhydride thread. Should I continue?
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hector2000
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| Quote: Originally posted by panziandi | Biotech is great for producing chiral compounds like l-PAC in that you have very high chiral-yield but unfortunently actual chemical yield is not
always very great.
My ideas are exactly that... ideas. Ideas of how to better a scale-up of the patent. I'm not selling them since I have not got the time nor equipment
to actually see if these ideas would better the reaction. Why don't you sit down, have a think about it and post some ideas of how you propose to
better the reaction and then people could comment and offer advice. People are not going to spoon-feed you.
You already suggested reducing the volume of petroleum ether to 2.5L, I can assure you taht that would result in something like marmite! But you are
along the right lines, you likely will not require 270L but you will require more than 2.5L... go figure some other varibales to potentially better
the reaction and read some texts and get ideas down then present them for constructive criticism from people on the forum, otherwise people will feel
like they are doing all the work for you and not getting anything in return, and you will end up looking lazy and having a bad reputation!
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I am Reading This Patent now:
http://rapidshare.com/files/6293040/thesis_l-_PAC.pdf
I am not lazy(never) but i am not complete human and this is very difficult to do lot of experiment for me.but i will try it
(because i am...)
I have some suggestion for this reaction and i will write it soon.
Mr sauron,
We want to check our small company can buil l-pac or cant.
We recieved order from pharmacy company and we want first research for making l-pac and make small amount(100 gram sample and test it with GC-Ms
Device for purity)
and check the price and other thing.
But i think this is not easy to make l-pac because very huge container needed and lot of solution,... but i will try it
and really want to now what do the indian or chinese company that there l-pac is cheap and pure.
[Edited on 27-4-2009 by hector2000]
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Sauron
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Biotech is not simple and not cheap.
Hygiene is critical.
Anyway, S.crevicea is not the ideal yeast, just the easiest to buy (baker's yeast = brewer's yeast)
Here is some related literature
[Edited on 27-4-2009 by Sauron]
Attachment: benzaldehyde.l-pac.pdf (267kB)
This file has been downloaded 1384 times
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hector2000
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Mr Sauron,
Making l-pac has cheaper or another method?
Before i think the cheaper and main method for making l-pac is yeast method(benz->l-pac)
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Sauron
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First of all there are many different yeast methods and many different yeasts.
There are continuous methods and batch methods.
BUT in every instance the capital costs are high and microbiology expertise is called for.
As has already been explained to you the point of using yeast is the enzymatic control of reaction to produce mainoly the L-disatereomer (typically
c.90% ee (enantiomeric excess).
Getting PhCHO to condense with pyruvic acid in an acyloin reaction is not I suspect difficult, but you will get an equal mix of D and L PAC (zero ee)
and then you must resolve the mixture
That is laborious.
So you choose between the scylla of biotech and the charybdis of achiral prep followed by conventional resolution.
My suggestion is: forget making L-PAC.
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hector2000
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Mr Sauron,
You want to say there is another yeast that may make more L-pac?
If this is possible may you explain more about chemical way for make PAC(acrloin reaction)?maybe this method better than yeast method(promise to god
that i search by google and yahoo and.. but i didnt find anything about this method)
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DJF90
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I agree with Sauron here, I'm getting fed up with your cluelessness and want of spoonfeeding displayed by this thread.
My suggestion: Use a chemical method. I believe freidel crafts acylation of benzene with oxalyl chloride, hydrolysing the resultant acid chloride and
then reducing the alpha ketone to a hydroxy with sodium borohydride should work. I doubt if it'll be an entirely clean reaction (perhaps some benzil
will be formed) and you will still have to resolve the stereoisomers, but it will be quicker than the biochemical method (I think), the scale of
reaction should be much more manageable (no massive heating costs or need for 240/330L reactor and sterile conditions) and as a smaller volume work up
should be easier also.
Disadvantages are having to work with benzene (not nice stuff) and oxalyl chloride (again not nice), with the latter being quite expensive IIRC
(sodium borohydride is also quite expensive). Thats assuming you have access to these chemicals.
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hector2000
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Thanks djf90
I am very interesting to know more about chemical method.
You dont know source or patent about chemical method?
I find out that bio method is diffrent,for example in this thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=1936
an according to patent: DD51651
we use 800gram cane sugar molasses,5g potassiumdihydrogenphosphate, 2,5g MgSO4.7H2O epsom salt, 16g ammoniumsulfate, 4liters water,164g yeast,32g
benzaldehyde and 48ml acetaldehyde we will get 20gram l-pac.
But i dont know this patent is valid or not
and attachment use urea!
[Edited on 27-4-2009 by hector2000]
Attachment: 433-437.pdf (214kB)
This file has been downloaded 4199 times
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Elena
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Acetylbenzoyl instead of L-PAC.
Any way, the L-PAC we mostly need to obtain ephedrine, so may be better to use other more efficient way?
Recently, I’ve got (from my friend) some theoretical recipe of obtaining racemic ephedrine
from Acetylbenzoyl aka 1-Phenyl-1,2-propanedione, via NaBH4 reduction.
As I know, no one practically tried this method yet. I am just planning to do that next month.
If someone interested to discuss about it, I will try to translate that article from Russian, and will post it here. Or may be I should open new
thread?
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Sauron
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DJK, FC with benzeme and oxalyl chloride will not produce the dione you describe (1-phenyl-1,2-propanedione) because oxalyl chloride has no terminal
methyl group.
You would do better with pyruvyl chloride but hector has already complained about the cost of pyruvic acod in Iran. Yje acyl chloride will noit be
cheaper.
C6H6 + (COCl)2 -> Ph-C(=O)-C(=O)-Cl
which is not what is wanted it is a-phenylglycollic acid (after hydrolysis and reduction) and prior to that it is phenylglyoxalic acid.
What is wrong with acyloin comdensation of PhCHO and MeC(=O)-COOH?
Eliminaes the NaBH4 step, and no need for the acyl chloride.
Same reaction just without the enzymatic assym. control. Product DL-PAC.
[Edited on 28-4-2009 by Sauron]
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hector2000
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In this link we can make phenylglyoxalic acid
http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv3...
phenylglyoxalic acid will convert to PAC easily?
also there is another way for making phenylglyoxalic acid:
-oxidation of acetophenone with potassium permanganate in alkaline solution
-oxidation of mandelic acid with potassium permanganate in alkaline solution
but Mr sauron you think we can convert phenylglyoxalic acid to PAC?I think this reaction will be difficult
[Edited on 28-4-2009 by hector2000]
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DJF90
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@Mr Sauron (sorry but you gotta laugh...): Sorry I thought that L-PAC was a carboxylic acid, not a ketone, hence my (bad) suggestion. I suppose I
should double check before I post but its not like its important 
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