A drive to halt the deterioration of flax-fibre artefacts, such as pre-European Maori cloaks and baskets, has resulted in a serendipitous discovery—that some species of flax have strong antifungal properties.
A treatment for flax-fibre has been developed by Gerald Smith of Victoria University and Rangi Te Kanawa of Te Papa, to prevent crumbling of the fibres over time caused by light, humidity and the acetic acid that builds up in them. (This ‘vinegar syndrome’ is even greater in fibre that has been dyed black with the iron-rich dye paru.)
To slow the breakdown of cellulose, which releases the acid, researchers coated the fibres with a spray made up of zinc acetate and sodium alginate (an extract from seaweed dries to a gel), which glued the fibres together and neutralised the acid. But while examining the different flaxes, they found enormous amounts of coumarin (the chemical also present in the smell of fresh-cut grass) and various metal ions, which are anti-fungal and pest-repellent.
The researchers now see potential for flax to be used in the manufacture of environmentally friendly containers that prevent fungal spoilage of food and other consumables.