Illustration by Belle Mellor
FOR a long time the public has perceived biotechnology to mean dangerous meddling with the genes in food crops. But biotechnology is of course about much more than transgenic food: it also encompasses the use of microbes to make pharmaceuticals, for example. The many benefits of the first wave of biotech products, in medicine, have unfortunately been overshadowed by the supposed risks of biotech's second wave, in agriculture. Might its third wave—so-called industrial biotech, also known as “white biotech” or “green chemistry”—resolve biotech's image problem?
As with other forms of biotechnology, industrial biotech involves engineering biological molecules and microbes with desirable new properties. What is different is how they are then used: to replace chemical processes with biological ones. Whether this is to produce chemicals for other processes or to create products such as biopolymers with new properties, there is huge scope to harness biology to accomplish what previously needed big, dirty chemical factories, but in cleaner and greener ways.
Sales of industrial-biotechnology products were about $140 billion in 2007, and 6% of all chemicals sales were generated with the help of biotechnology, says Jens Riese of McKinsey, a consulting firm. Steen Riisgaard, chief executive of Novozymes, a biotechnology company, says he imagines a future in which bio-refineries are dotted around the countryside producing fuels and other chemicals from biomass such as agricultural waste.
One company which has been working in industrial biotechnology for years is DSM, based in Heerlen in the Netherlands. In the 1990s it started making enzymes for cheese and omega-6 fatty acids for infant formulas, and went on to develop a biological process to produce cephalosporin, an antibiotic, in a much cleaner way than the chemical processes used to make the drug. Its most recent effort has been to find a biological way to produce a chemical called succinic acid (C4H6O4), which is used to make a wide range of products including spandex, biopolymers for agriculture, de-icing salts, esters, resins and acidity regulators in foods.
The usual chemical process involves making succinic acid from crude oil or natural gas. DSM's biological approach is based on fermentation using enzymes and genetically engineered microbes. After a successful pilot-production phase, the next step is a demonstration factory in Lestrem, France, which will be running by the end of the year. If that goes well, a much bigger commercial operation will follow. The company says that as well as making succinic acid from biologically derived starch, rather than fossil fuels, its process also uses 40% less energy and produces fewer carbon-dioxide emissions.
Novozymes, as its name suggests, has focused its attention on supplying optimised enzymes—biological molecules that help make reactions happen faster, or at lower temperatures. This sounds trivial but it can make the difference between a commercial and a non-commercial process. The company says it has 47% of the market for industrial enzymes, which are used in areas such as detergents, brewing, baking or to produce animal feeds.
Enzymes are the first tool of choice in white biotechnology if the chemical conversion process is a fairly simple one. But if a more complicated series of reactions is required, or the enzyme in the process is used up during conversion and needs to be regenerated, it is time to reach for a microbe. Microbes can accomplish hundreds of chemical tasks at the same time and are able to recreate the enzymes they need. Novozymes is working on a biological process to make acrylic acid (C3H4O2) from starch or biomass rather than fossil fuels. One stage uses optimised enzymes, and another is carried out by engineered microbes.
Creating a suitable microbe involves starting off with one that does part of the job in question, and then convincing the microbe to specialise in that activity. (DSM found its microbe, a yeast, living in elephant dung, where it broke down cellulose in starch; Novozymes started out with a bacterium from its large library of microbes.) The next stage is to eliminate the things the microbe does that are not related to the task in hand by inactivating non-essential genes. The modified microbes are then produced in large numbers and those that are best at the job are selected. The result is a bug that is specially adapted for a particular task.
Novozymes says it is close to completing its acrylic-acid process. Around 40% of acrylic acid produced is used to make super-absorbent material like that found in nappies (diapers); most of the rest goes into paints and coatings. Novozymes says its process will be competitive with chemical methods at an oil price of $60 a barrel or higher. Given the large size of the acrylic-acid market and its steady growth (4% a year), Novozymes is confident that its process will grab a decent share.
Proponents of industrial biotechnology are optimistic that they can avoid the pitfalls that hindered the adoption of biotech crops, which have been criticised by their opponents as unnatural “Frankenfoods” that extend corporate control of agriculture. For one thing, unlike transgenic tomatoes, say, industrial-biotech products are not sold directly to consumers. And instead of displacing “natural” products with bioengineered alternatives, as in agriculture, industrial biotechnology generally displaces fossil fuels and their associated chemical processes with greener biological alternatives. Surely that should make it easier to convince people of its benefits, and hence to rehabilitate the notion of biotechnology more widely?
One problem is that even though the raw materials used in industrial biotechnology may not be derived from fossil fuels, they are still capable of stirring up some difficult ethical questions. In particular, using food crops like maize as raw materials to make biofuel is already hugely controversial because of its impact on food prices. And even growing non-food crops for industrial use is problematic, because it can reduce the land available for food production.
The use of agricultural waste is less controversial. Mr Riisgaard reckons that converting agricultural waste into other chemicals (including fuels) using industrial biotechnology could replace 20-25% of global oil consumption. And there is plenty of waste about. He also suggests that raw materials could be grown on marginal land which is unsuitable for food production. That is true, but it could have knock-on effects on biodiversity. Perhaps the most promising approach for advocates of biotechnology's third wave is to emphasise the potential for a new, greener chemicals industry to create jobs in remote rural areas.
This article appeared in the Technology Quarterly section of the print edition under the headline "Third time lucky"