San Diego-based Sapphire Energy Inc., which is using algae to produce “green crude” oil that can be used for fuel, has raised $144 million in Series C investment financing. This latest round boosts Sapphire’s total funding to well beyond $300 million.

Series C backers include Denver-based Arrowpoint Partners, St. Louis-based Monsanto Co., and undisclosed investors, the company said. All major investors from the prior round participated.

Sapphire said the funds will help advance its commercial demonstration project at its “Green Crude Farm” in Luna County, N.M. The farm, also known as the Integrated Algal BioRefinery, is the world’s first commercial-scale algae-to-energy facility. The project integrates the entire value chain of algae-based fuel, from cultivation to production to extraction of ready-to-refine Green Crude, Sapphire said.

Some proceeds from previous closes of the Series C financing already have been invested in Sapphire Energy’s continuing operations.

“The ongoing support from the private investment community speaks to how strongly they believe in the development of Green Crude as an alternative fuel resource, especially Sapphire Energy’s ability to commercialize it,” Cynthia J. Warner, president and chairwoman of Sapphire Energy, said in a statement.

Warner said that it’s increasingly important to find domestically produced crude oil alternatives to improve the country’s energy security, meet global energy demands and provide jobs.

Jason Pyle, CEO of Sapphire Energy, said in a statement that the company is “well positioned to achieve the goal of bringing domestically produced Green Crude oil to commercial scale.”