in the example is an enzymatic conversion or biotransformation that also typically runs in water.
Figure 4 is an example of an Aji Bio-Pharma project where we conducted phosphorylation in water using POCl 3
. Chemists would never do POCl 3 chemistry in water; however, in this case, it worked perfectly fine and 98 % phosphorylation is observed versus only 2 % free phosphate forming.
Another important tool to drive sustainable innovation is using enzymes from fermentation. For example, a typical chemical process to tweak sugar is to decorate the sugar with protecting groups, remove one protecting group, modify the free alcohol, then do a general deprotection.
Reducing the number of stages through a biotransformation requires metabolic engineering of enzymes to ensure that the enzyme effectively and selectively does its job and will do it in a highly concentrated medium. This enzyme can be produced through fermentation, a possible pathway offered to our customers.
Third, we apply enzymatic or whole cell chemistry in practice. Our team has experience with transaminases, esterases, phospholipases,
Figure 3 – Example of green chemistry process
Note: Ref: Green Chem., 2021, 23, 788-795
dehydrogenases, laccases, oxidoreductases and more.
If water is an ineffective replacement, green solvents are the next step. There are a number of green solvents, some of which have a high footprint on their own, and they need to be chosen carefully. Consider the following:
• Does the green solvent have a large footprint that requires a lot of stages and purification?
• Should feedstock still be used to make solvents?
• Is it wise to develop processes using a solvent that may not be acceptable ten years from now?
The focus of renewable solvents is solvents from CO or CO 2
. One is closing the cycle by using CO 2 and making formic acid, acetic acids, methanol, ethanol, etc. Besides biorenewable solvents, new technologies are becoming available. You might conduct chemistry above the boiling points of solvents rather than refluxing, which is energyconsuming and demanding.
Leverage innovation strategically
Rather than using precious metals with massive footprints, base metals present a compelling alternative.
Figure 4- Aji Bio-Pharma example, 3 volumes of water, 98 % yield calculated versus POCL3
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