Melanin is a class of naturally occurring pigments found in living things. It is produced via a multi-phase biochemical process called melanogenesis. In humans, it manifests as the natural pigment of the skin and hair. Not only is melanin a color pigment, but it also serves the function of protecting the skin and hair from the adverse effects of long term exposure to ultraviolet radiation.

Melanin is also a common component in the leather manufacturing industry. Real leather is made from animal skins/hides, and these skins have melanin. If the melanin pigments are not adequately removed, it leaves the finished leather with a patchy and rough appearance.

There are various methods of extracting melanin content from leather, but the most frequently used are enzymatic reactions. As the leather industry evolves into bioprocessing,  a good number of researchers are carrying out an extensive study on the best enzyme to remove melanin from leather. And the majority of findings have pointed towards one protein- Xylanase.

Xylanase is a group of enzymes that can degrade linear polysaccharide xylan into xylose. It is naturally synthesized by fungi, bacteria, yeast, marine algae, protozoans, snails, crustaceans, insects, seeds, etc.

To successfully remove melanin from leather, Xylanase has to be introduced in large quantities. In a research carried out by a group of Indian scientists on "Enzymatic Removal of Melanin in Enzyme Based Dehairing and Fibre Opening,"  melanin pigments were removed from buff calfskins using various concentrations of Xylanase. It was concluded that the rate of removal of melanin is directly proportional to its concentration with a maximum threshold of 0.5%.

Xylanase was proven to have a 100% capacity to rid leather of melanin pigment. What Xynalase does is sever the bond between the adhering matter (glycan based) present between the epidermal and the melanin layer.

 α-amylase can also serve as a supportive enzyme; it speeds up the melanin removal process.

With these two enzymes, removal of melanin from leather will be a workover.

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