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Enzyme use for PLA??? (1 Viewer)

Michaelmoo

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Hey there. Does anyone know the names of any enzymes used in the synthesis of Polylactic Acid. Does anyone know the answer or have any general resources about this???

THanks.
 

munchiecrunchie

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i think its lacto bacillus and rhizopus orgae (check the spelling of the 2nd one)
 

appletooth

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Lactobacillus bacteria or a type of fungi called 'rhizopus oryzae'. Neither are "enzymes" though. They're microorganisms. (Read the syllabus dot point closely – it says enzymes OR microorganisms'.)

Steps in the synthesis of PLA:

1. Corn or sugarcane is milled to extract the starch.
2. Dextrose is extracted from the starch.
3. Dextrose is anaerobically fermented with lactobacillus bacteria or rhizopus oryzae to produce lactic acid.
4. Lactic acid undergoes condensation polymerisation to produce a cyclic lactide dimer.
5. Vacuum distillation is used to purify the cyclic lactide dimer.
6. A solvent-free polymerisation process is used to produce polylactic acid.
 

gualtieri

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I found that the enzyme was

glucoamylase

hope that helps. If its wrong can u please let me know
 

Rachaek

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I had these as the steps for creating PLA:
- Corn milled to separate out the starch
- Alpha amylase enzyme breaks down starch molecules
- Glucoamylase breaks molecules down further into glucose
- Glucose fermented to produce lactic acid
- Condensation reaction to join two lactic acid monomers to lactide
- Purified by vacuum distillation
- Polymerised to form polylactic acid polymer

So, alpha amylase and glucoamylase are the enzymes used.
 

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