Aventine Renewable Energy Holdings Inc. (NYSE:AVR) is down 9% today after Lehman Brothers downgraded the alternative fuels company to “underweight” from “equal-weight.” The analyst said that falling corn prices have not improved ethanol production margins. The Pekin, Ill.-based company produces and markets ethanol. Record-high corn prices have cut into its margins and the stock is down 53% since January.

In today’s trading, shares are at $6.02 at 10:30 a.m. ET, down $0.61 from Friday’s close. The stock has ranged from $3.66 to $17.23 during the past year.

For detailed price information and recent news stories about Aventine Renewable Energy Holdings Inc., click AVR.