NEW YORK ( The Deal) -- With its overall financial results bogged down by an unprofitable joint venture, alternative fuel and renewable energy company Syntroleum Corp. ( SYNM) has enlisted Piper Jaffray & Co. ( PJC) to explore its options, including a sale. While both the company and its adviser at Piper Jaffray, J. Thomas Halverson Jr., declined comment, Tulsa, Okla.-based Syntroleum said in a statement Wednesday that the Minneapolis investment bank would assist in reviewing options for its assets related to renewable energy and its natural gas-to-liquid refining businesses. The review comes amid some troubling times for Syntroleum, which focuses on the production of synthetic fossil fuels as well as traditional crude oil refining. The company has posted a net loss in three of the last four years, including a $1.1 million loss in 2012. Syntroleum, which trades on the Nasdaq as SYNM, struggled last year to stay above the minimum bid requirement of $1 per share. After Nasdaq threatened to delist the company several times, Syntroleum in April enacted a 1-for-10 reverse stock split to raise the price above $1 and avoid that fate. Since the reverse stock split became effective on April 15, Syntroleum's share price has actually rebounded to more than $7 from $3.52 per share on April 15, the day the reverse stock split went into effect. Despite the uptick in stock price, Syntroleum's 50-50 joint venture with Tyson Foods Inc., called Dynamic Fuels LLC, has hurt the former's profits, or lack thereof. The joint venture, which runs a Geismar, La., biofuel plant, specializes in turning food and animal waste and other byproducts of the food production process into biodiesel fuel. The enterprise, however, hasn't turned a profit in more than a year. In fact, for the quarter ended March 31, the JV posted revenue of $6.7 million, or more than half of Syntroleum's $11.6 million in total revenue for the quarter. But the JV had a net loss of $830,000 for the period on top of the $11.8 million loss it sustained last year. Both Tyson and Syntroleum each invested $5.7 million in cash and working capital loans into Dynamic Fuels in the first three months of this year to fund operations at the Geismar plant.