Saturday, 22 October 2011

Hydrophobins the Magic Inside Mushrooms

In Finland mushroom picking is a big thing.  You go into the forest with a paper bag and search for different kinds of mushrooms.  In Finland this is a popular past time and a highly guarded secret so people will not discover your hidden mushroom treasure in the forest.  Many of these mushrooms that you can find in Finland can be in the range of 25 euros a kilo.  So if you are picking or shrooming as they like to call it and you come out of the forest you have to be prepared if someone asks you, 'where did you find all those mushrooms?'  a common answer is 'I got lost in the forest and I cannot remember,' or 'I was just walking my dog and found these.' When you get home you can fry them up and put them in an assortment of dishes like wild mushroom risotto.

I have a jar of dried mushrooms right now in my kitchen cupboard.  I just learned that they have some interesting biochemistry in the cap of the mushroom. The mushrooms that I found in the forest is the fruiting body of a fungus.  On the mushroom cap a protein exists called hydrophobin.  These proteins contain surface active properties allowing the producer fungi to attach support structures, create air gaps through air-water interfaces, grow hydrophobic parts.and keep the mushroom dry.

 The really cool thing is how they can change the surface of materials by forming a film on the surface of a material modifying the interfacial energy of the interface.  The films can be measured using a langmuir microtrough with a tensiometer and a potentiometer.  On hydrophilic surfaces hydrophobins assemble their hydrophobic side to the solvent, and vice versa.   So if water interacts with glass normally it will run off like a film or disintigrate into smaller droplets and if water interacts with teflon (a hydrophobic surface) it will cause a lotus effect.  When you add hydrophobins to each of these the glass will be hydrophobic beading the water making a lotus effect and the teflon will turn hydrophilic.

What can you use these?  I think the full extent has not been found.  One thing is they can modify the surface of textiles to make kind of a biomolecular goretex on textiles that maybe do not look like goretex. (1) Possibly someone can make a spray out of this.   Nanoscale drugs have been made using hydrophobins to coat poorly soluble molecules and drastically increase  their solubility. (2)

BASF is the first company with the capability to manufacture hydrophobin on an industrial scale. They have some great videos (here).  Hydrophobins are studied by a VTT researcher named Markus Linder.

1. Klaus Opwis & Jochen S. Gutman (2011), Surface
modification of textile materials with hydrophobins. Textile
Research Journal 1594-1602
2. Hanna K. Valo et al (2010), Multifunctional Hydrophobin:
Toward Functional Coatings for Drug Nanoparticles. ACS
Nano 1750-1758


  1. Replies
    1. Nature has a way of making things that humans are only catching up to. New biomimcry designs are coming out all the time where we make materials, like hydrophobins, that are similar or better than their natural counterparts. Thanks for your comment!