I have been doing some experiments concerning bleaching of chlorophyll stains from cotton clothing. Currently I have found that $\ce{H2O2}$ is fairly effective, but still leaves visible stains. Would a crude Horseradish root extract containing peroxidase get me better results?

The reason I'm asking about the crude extract and not the purified enzyme is because I don't have access to a laboratory or more complex materials and my work also aims to produce simple methods of chlorophyll degradation that could be replicated at home.

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    $\begingroup$ Chlorophyll is not well soluble in water. Since your cotton clothing might have been dyed prior to the unwanted exposure to chlorophyll, you could try th following cleaning agents first at a spot less visible and if they do not remove your clothing colors, apply them on the stain: a) vinegar, or b) pure alcohol, or c) some of luke-warm water + bile / gall soap brushed over the stain and allowed to sit there four an hour at ambient conditions prior to a normal wash. By own experience, if you know there were stains there, you will be more likely to see them even if others do not spot them. $\endgroup$ – Buttonwood Jul 6 '19 at 15:07

Horseradish peroxidase is not hydrogen peroxide, $\ce{H2O2}$, but rather an enzyme that breaks $\ce{H2O2}$ into $\ce{H2O}$ and $\ce{O2}$. In general, enzymes ending in -ase are lytic enzymes, catalyzing the breakdown of a similar-sounding substance. So, if you add ground horseradish to hydrogen peroxide, bubbles of oxygen are released. BTW, horseradish roots differ in peroxidase potency, so test beforehand with a particular batch before doing this as a demonstration... sometimes it fizzles out, or not.

Another example of lytic enzyme, amylase in the mouth, breaks apart amylose in starch, so a starchy cracker tastes sweeter as it melts in your mouth.

As @Buttonwood suggests, alcohols, ether and oils are more effective solvents than water.


$\ce{H2O2}$ is Selective

The reason why hydrogen peroxide can be used for such diverse applications is the different ways in which its power can be directed -- termed selectivity. By simply adjusting the conditions of the reaction (e.g., $\mathrm{pH}$, temperature, dose, reaction time, and/or catalyst addition), $\ce{H2O2}$ can often be made to oxidize one pollutant over another, or even to favor different oxidation products from the same pollutant. (From http://www.h2o2.com/products-and-services/us-peroxide-technologies.aspx?pid=112)

You might try mixing 3% $\ce{H2O2}$ with vinegar, ~1/1, or with $\ce{Na2CO3}$ (washing soda), and applying these materials to first, a small test spot, and then the stain. Many times, alkali will solubilize contaminants that aren't easily oxidized - and perhaps addition of a little surface-active agent, like dishwasher soap, can assist removal of oleophilic stains. Some commercial pre-wash stain removers also contain butyl ethers as solvent and surface tension reducer.

And if the clothing is white, there is always chlorine bleach (sodium hypochlorite)!


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