Ethanol isn't the only bioproduct making its way to the mainstream. Oils, lubricants, polymers, and even raw materials for perfume can be made from plants these days. Not everyone is a fan of ethanol, especially in the U.S., but other bioproducts raise interesting possibilities about what this technology can be used for. Here are five companies to keep an eye on.

Amyris (Nasdaq: AMRS) uses its industrial synthetic biology platform to turn sugars into hydrocarbons. The company's first commercial facility in Brazil was just completed, and its first renewable product, No Compromise squalane, is now being delivered to customers. Amyris can produce industrial lubricants, polymers, and transportation fuels with its technology.

Syntroleum (Nasdaq: SYNM) can turn fats, oil, greases, and natural gas, among other things, into liquid fuel. The company has a joint venture with Tyson Foods (NYSE: TSN) called Dynamic Fuels, which turns Tyson's waste into fuel.

Rentech (AMEX: RTK) still gets a majority of its revenue from fertilizer, but the company is gaining momentum in alternative fuels. The Rentech's Olympiad Renewable Energy Centre in Ontario has been selected to receive wood supply to generate RenJet fuel. The project will produce 23 million gallons of gas and 13 million gallons of chemical feedstock and is scheduled to open in 2015. The low-carbon jet fuel is certified for commercial aviation use. 

Rentech also recently completed the acquisition of a majority stake in ClearFuels Technology, an advanced biofuel-technology company that it had previously partnered with.

Newcomer Solazyme (Nasdaq: SZYM) hit the market less than two weeks ago but is already capturing a lot of buzz. The company uses microalgae to eat plant-based sugars and produce renewable oils and bioproducts. Compared with the other companies we've discussed, that's a different process for making bioproducts, but the inputs and outputs are similar.

Solazyme's most lucrative market initially may be high-value inputs for products such as cosmetics and perfumes, where specially designed chemicals fetch a premium. Nothing quite like spraying algae excrement on yourself to spice up a date, eh?

Finally, Gevo (Nasdaq: GEVO) uses a yeast biocatalyst to convert sugars from a variety of feedstocks to isobutanol. This product is then separated from water and can be used to make products such as rubber, plastics, and fuel. The company's first commercial-scale biobased isobutonal facility in Minnesota was announced just last week.

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