Your Next Designer Bag Will Be Made Out of Mushrooms

From fungi to spider silk, the hunt for sources of climate-friendly clothes and leather alternatives is getting creative

Credit: taviphoto/Getty Images

Around the turn of this millennium, when everyone else was busy worrying about the Y2K bug, researchers at Nexia, a secretive biotechnology firm based in Montreal, had other, bigger critters on their minds. Goats, to be precise. Although they looked just like regular goats and were given cute names like Sugar and Spice, they were, in fact, extraordinary. They had been genetically modified with spider DNA, so that their milk contained silk proteins that could potentially be spun into thread softer than the finest Egyptian cotton, and stronger than Kevlar.

In the end, spider-goat silk never took off. Nexia went bust, the silk-making herd were sold off and, although research is ongoing, the odds on a comeback have never looked good. Dreams of groundbreaking new textiles, however, are still very much alive, and very necessary.

Textile manufacturing, particularly for the fashion industry, has a deservedly dirty reputation. It is a major polluter and consumes vast quantities of water. Around 60% of the materials we wear are made from plastics — principally polyester, acrylic, and nylon. Each time they’re washed, these garments release microplastics into the environment — adding up to around half a million tons annually — endangering wildlife and our own well-being. “We urgently need to know more about the health impact of microplastics because they are everywhere — including in our drinking-water,” Dr. Maria Neira, the World Health Organization’s Director of Public Health, has said.

Given these environmental costs, and the fact that depletion of fossil fuels will eventually make synthetic textiles more expensive, the industry is coming under mounting pressure to invest more of its $3 trillion value into cleaning up its act. This means looking for environmentally friendlier textiles that could take the place of the plastic synthetics.

One option is Piñatex. Developed by Carmen Hijosa, a veteran of the leather industry, Piñatex is an unwoven material made from pineapple leaf fibers from the Philippines. Each pineapple grows in a bush composed of around 25 long, slender and fibrous leaves. These are usually discarded or are burnt once the fruit is harvested, which, since pineapples are the world’s second biggest tropical fruit crop, means 13 million tons of leaves are wasted annually by the top 10 pineapple producing countries alone.

Ananas Anam, Dr Hijosa’s firm, is currently transforming a tiny fraction of this byproduct into Piñatex. Pineapple farmers collect the leaves and use a threshing-style machine to remove their long, pale fibers. These are then worked into a textile in a process similar to felting. The finished product can be dyed or given a metallic finish, and is already being used by brands including Boss and Artesano to make everything from car seats to sneakers to watch straps.

Fruit waste is also the starting point for the companies Green Whisper (bananas), Vegea (wine grapes) and Orange Fiber (citrus). The last discovered that extracting the cellulose from leftover fruit rinds and pulp, breaking it down chemically and spinning it, resulted in a silky yarn suitable for clothing manufacturing. The threads can be used alone or blended with silk to produce a variety of weights and finishes. Technically, the manufacturing process is similar to making rayon or viscose, already widely used by the textile industry, but Orange Fibre has an environmental advantage because their raw material is a waste byproduct of an existing industry, rather than a dedicated crop, such as bamboo or, worse still, virgin forest. They have previously collaborated with Salvatore Ferragamo and, this year, their yarn was used by H&M as part of the brand’s Conscious Exclusive collection.

H&M Group — whose brands include COS and & Other Stories — are one of the fashion industry players investing in new, sustainable textiles. “We are a large company,” CEO Karl-Johan Persson said recently, “and we therefore know that we have an equally large responsibility to ensure that we have a positive impact on our planet.” Right now that feels some way off, but the group has increased the share of recycled and sustainably sourced materials they use from 35% in 2017 to 57% in 2018. Anna Gedda, H&M’s head of sustainability, says the company has committed to a goal of only using sustainable packaging by 2030, although they haven’t set a date for their more ambitious aim of complete sustainability.

Algae and seaweed is another promising resource. Pangaia, an American firm with a celebrity fan base that includes Pharrell Williams, makes clothing from cotton blended with seaweed fiber pepped up with peppermint oil, which reduces the need for washing. “Sustainably produced; sustainably consumed” are the brand’s watchwords — even the packaging is compostable. AlgiKnit, based in Brooklyn, is working the same seam. They are currently prototyping a T-shirt made from alginate extracted from fast-growing kelp that doesn’t need pesticides or fertilizers or, indeed, any land.

What a mushroom can accomplish in two weeks in a bag in a dim room might take a cow two years, thousands of kilograms of food and medicines, as well as a good deal more space.

MycoWorks, a San Francisco-based firm, is making use of another fast-growing resource to make textiles: mushrooms. The process begins with spores injected into bags of common agricultural byproducts such as corn husks, paper pulp and sawdust. These raw materials are then colonized by the root-like mycelium of the fungus, which grow through them and begin to break them down to feed the fungus.

Once this process is complete — taking days or weeks rather than months — MycoWorks has a product that behaves a lot like leather. It’s water resistant, breathable, strong, and flexible; it can be colored. But it has significant advantages over the original: It can be grown to a specific size, shape, even texture, it is biodegradable, doesn’t use animal products, and requires significantly less time and resources to make. What a mushroom can accomplish in two weeks in a bag in a dim room might take a cow two years, thousands of kilograms of food and medicines, as well as a good deal more space.

Bolt Threads, another Californian biotech startup, are also harnessing fungi. Their Mylo leather substitute was used in 2018 by the British designer Stella McCartney to build a prototype of their Falabella handbag, currently made entirely from polyester. But Mylo isn’t the firm’s only foray into textiles. Like Nexia before them, Bolt Threads is trying to make commercial quantities of spider silk without the spiders.

Unlike silkworms, spiders can’t be domesticated. For one thing, they don’t produce as much silk. A silkworm cocoon might be made from a continuous, 900-meter silk thread. Spider webs and egg sacs require a lot less, and manually silking individuals is an arduous process, particularly for the spiders. Another problem is that they are aggressive and territorial — attempts to farm them usually end in carnage and disappointment.

This is, in part, why Nexia hit on the idea of using spider DNA in a larger and more docile animal. Bolt Threads, though, have gone in a very different direction, using genetically modified yeast to make their Microsilks. This theoretically allows them to design fabrics from the molecular level up. By looking at the properties of naturally occurring silk proteins, they can select those with the properties they want, be it softness, durability or strength. (Individual spiders can often produce half a dozen different kinds of silk for use in webs, egg sacs, or for strong draglines used to make a speedy getaway if they’re attacked.)

Bolt put their own spin on these proteins, using adapted yeasts to produce them through fermentation, a process similar to making beer. The proteins can then be extracted and spun into silken threads. While not yet widely distributed — so far, the firm has only sold limited-edition ties, hats, and a one-off dress exhibited at MoMa — commercial spider silk is beginning to feel tantalizingly close. Perhaps it’s time for Sugar and Spice to come out of retirement after all.

Best-selling author of THE SECRET LIVES OF COLOR & THE GOLDEN THREAD. Bylines in The Economist, TLS, Elle Deco, World of Interiors, here. Culture|Design|History

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