The Silk Worm – A living factory
Did you know that the domesticated silk worm produces two types of silk protein, both of which are useful for us cosmetic junkies?
Firstly theres the firboin which is full of glucoproteins – a really useful type of sugar and the primary reason that silk is so great for keeping the skin silky smooth and moisturised. Fibroin also has great insulating properties thanks to its long-chain structure which also allows it to form a mesh and prevent delicate actives being lost from the skin – think of it as a silky spiders web! It’s long, smooth chain structure also make it amazingly soft and silky which is goes some way to explaining why silk is so……silky!
Secondly theres the sericin. This is a macromolecular protein that acts as the glue that sticks the silk worms silk together and helps form the cocoons. The term ‘macromolecular’ means large as these proteins contain bundles of small molecules all meshed together to create something new. Sericin’s main skin-friendly properties are those based on its anti-oxidant, nutrient and coagulant abilities making this the perfect addition to any product aimed at wound healing or barrier repair.
Both of these proteins are available in purified 100% ‘active’ form for the cosmetic chemist either as separate ingredients or combined in silk protein thanks to our ability to isolate and extract the different fractions. This makes it possible to create a silk-containing cosmetic with moisturising powers far in excess of what can be gained from pure un-touched silk alone AND with a much softer skin feel to boot. Further, if you want all of that goodness to penetrate further into the skin the proteins can be sliced and diced into their corresponding amino acids for a more targeted range of benefits. However, for the purists the whole package is also available as a water-soluble silk protein powder as nature intended.
Silk, yet another example of what’s possible when nature and science combine.