Rainforests have long been known as remarkable natural laboratories of life-saving and life-enhancing medicinal drugs (not to mention some mind-expanding illegal drugs as well). Now it turns out they may be natural laboratories for biodiesel fuels that could potentially power clean cars and trucks.

Montana State University's Gary Strobel says his team of researchers has discovered a fungus that breaks down plant cellulose directly into diesel compounds without any added enzymes or extra steps. The fungus lives in the Ulmo tree in the Patagonian rainforest.

Strobel said of their discovery, "The results were totally unexpected and very exciting and almost every hair on my arms stood on end."

The team is now working on steps to make the biodiesel production process commercially viable. They'll have competition from another rainforest inhabitant, a freshwater species of green algae discovered in Thailand. One Thai scientist estimated that a commercial farm of this algae could produce as much as 136,900 liters of oil per hectare.

Researchers had better move fast to investigate the remaining riches of the rainforest. By some estimates, 80,000 acres of rainforest are burned, plowed or otherwise destroyed every single day.

A roundup of green headlines that caught our eye this week:

• Green pumpkins? Add Halloween to the greening of everything. The Baltimore Sun notes that a "Green Halloween" movement is spreading across the land promoting organic candy, fruit, other wholesome treats, and even costumes made of natural fiber. This Halloween vet, however, will stick with a traditional bowl of chewy gooey candy bars for the wee goblins tonight.
• More greening: The New York City Marathon this Sunday will add biodiesel generators to power official race clocks, loudspeakers, a medical tent and other fixtures at the race's finish line in Central Park. The generators, developed by the GreeNow company, run on 99 percent biodiesel made from U.S.-grown soy, according to The New York Times' City Room blog.
• Senators Obama and McCain are getting a lot of advice from scientists, The New York Times' Dot Earth blog reports. The American Association for the Advancement of Science and some 180 other organizations want the next president to appoint a White House science adviser with cabinet-level rank to provide scientific and technical advice on energy security, climate change and other issues. The groups grumbled that the Bush administration was slow to appoint a science adviser and didn't give the post cabinet rank.

If you're an olive lover, don't throw out those pesky pits: in the right hands, they could be a valuable new source of energy (or moonshine), according to Spanish researchers.

According to a study published in the Journal of Chemical Technology & Biotechnology, olive stones are rich in natural chemicals that can be converted to sugar and then to ethanol. The process uses high-pressure hot water to produce the sugar and yeast fermentation to produce ethanol.

For every 100 kilograms of olive stones you save, count on being able to produce 5.7 kilograms of ethanol with the right equipment. Just be sure to check with your spouse before making any plans.

Investments in clean technology startups hit a record $2.6 billion in the third quarter, a 37 percent jump from the third quarter last year and a 17 percent hike over the second quarter this year, according to a report out this morning from the Cleantech Group. Total investments so far this year -- $6.6 billion -- are running ahead of $6 billion for all of 2007. California-based companies hauled in 42 percent of the investments.

Venture capital firms invested in 158 companies globally with a focus on three principal sectors -- smart power grids, algae companies, and solar power developers. Electric grid companies raised a record $202 million in the period, reflecting the growing move into plug-in electric vehicles by major automakers. Algae biofuel producers took in $95 million and solar power startups raised a record $620 million.

"Cleantech venture investing has continued to show strong growth despite the unprecedented turmoil in the credit markets during the quarter," said Michael Goguen, managing partner of Sequoia Capital and co-chair of Cleantech's advisory board. Cleantech is an investor group and market researcher.

Brian Fan, senior director of research for the Cleantech Group, said the third quarter "will probably be the high point for investment for at least several quarters," citing the current financial and economic troubles.

The five most active investors in the third quarter in the number of deals all have connections to Silicon Valley. RockPort Capital Partners topped the list with six deals, followed by Google Inc. with five, Advanced Technology Ventures and Kleiner Perkins Caufield & Byers with four each, and Khosla Ventures with three.

Both Kleiner Perkins and Khosla Ventures have invested in Ausra Inc., a solar-thermal energy systems company which is developing a solar plant for PG&E in central California. Ausra announced today that it has secured $60.6 million in its latest preferred equity financing from a group led by KERN Partners of Calgary, Alberta.

In the old days, kitchen grease was a messy waste product that unscrupulous restaurant owners dumped illegally to avoid disposal fees. In today's greener age, this leftover sludge has instead become a valuable target of thieves who reportedly convert it into clean biodiesel at a cost of less than $1 per gallon. That's progress for you.

On Friday, Governor Schwarzenegger of California addressed that problem by signing into law a bill that will slash fees imposed on individuals who collect and recycle fryer grease for their personal use as a substitute for diesel fuel.

The law, sponsored by Good Earth Grease Haulers in Monrovia, aims to support biodiesel production by cutting vehicle transport fees from $400 to $75. In theory it will also discourage the stealing of oil by getting more haulers to register with the authorities.

Now if we could only lick the problem of thieves who rip off solar panels from rooftops and then resell them on eBay. Is nothing sacred?

A roundup of green headlines that caught our eye this week:

• Sustainable is one of the top categories featured on NEXT100, so Andy Revkin's post on sustainable cities on his DotEarth blog seemed right for this week's roundup. Portland, Oregon, again topped a list of 50 U.S. cities compiled by SustainLane.com, a publisher that reviews things that are supposed to be good for you. The Rose City has topped the list for social and environmental sustainability since it began in 2005. San Francisco was No. 2 for the second consecutive year.
• Another piece on sustainability:environmental and aid groups are urging wealthy industrial countries to pay poorer nations to preserve their forests and jungles. Tropical forests absorb carbon dioxide, the main greenhouse gas. Deforestration releases large volumes of CO2, threatening to cancel out emission reductions elsewhere. 
• A U.N. report this week -- "Green Jobs: Towards Decent Work in a Sustainable, Low-Carbon World" -- says more than 20 million jobs could be created as countries move toward new energy sectors, including wind, solar and geothermal power. Some 2.3 million people are now working in alternative energy jobs, with half in biofuels, according to the report.
• Shifting gears to plug-in vehicles, Montreal-based Dorel Industries is introducing a lithium-ion-battery-powered "e-bike" -- the Schwinn Tailwind. It claims to recharge the battery in only 30 minutes compared with four hours or more for a standard e-bike. The price: $3,200 (U.S.). 

A roundup of green headlines that caught our eye this week.

• A $10,000 premium for the GM plug-in Chevy Volt's lithium-ion batteries probably means a long wait for affordable electric cars.
• Wanted: Wildlife Biologists. Solar energy developers are snapping up biologists to survey power plant sites in California (including a PG&E project) and the desert Southwest for protected species and to prepare habitat-protection plans.
• A rival for Cow-Power? Food giant Kraft has found a way to turn whey, a cheese byproduct, into biomethane gas to power dairy plants. Will this frighten Little Miss Muffet?
• While Google eyes wave-powered floating data centers on the high seas, San Francisco-based International Data Center plans to dock retrofitted data center ships at piers and take electricity from nearby utilities, reducing operating costs.

Californians are familiar with innovative programs to tap new resources to produce renewable energy. PG&E, for example, is a leader in "cow power" -- producing renewable natural gas derived from cow manure at large dairy farms.

Now, a very different waste source is generating a novel biogas: tofu. Reuters reports today from Indonesia that tofu factory waste is being converted into energy.

"Indonesians in a central Java village are turning tofu factory waste into energy, reducing both air and water pollution and offering an alternative to fossil fuels. Soy-rich wastewater is left to ferment, and the biogas produced is used by two tofu factories and 20 households in the area," Reuters reports.

Adding to the list of breweries going green, Anheuser-Busch today announced that one in seven of its beers made in the U.S. will be brewed using renewable fuel by the end of 2009. The nation's largest brewer is turning to a combination of clean technologies to brew renewably, including biogas from a local landfill, solar and BERS, a technology that turns brewing wastewater into fuel. Once these projects are complete, 10 of Anheuser's Busch's 12 U.S. breweries will be producing renewable fuel.

If craft beer is more your style, you needn't look any further than the über-green brewery Sierra Nevada. This company has it goin' on full-circle style and is aggressively working to achieve 100% energy self generation. Their impressive efforts include incorporating a one megawatt fuel cell system, recycling, heat recovery, CO2 recovery, energy efficiency, water conservation and byproduct recycling. What's more, they're cataloguing their carbon footprint with the California Climate Action Registry and offsetting the emissions associated with their purchased energy through PG&E's stringent ClimateSmart program.

I'll toast to that!

Venture investments in "clean technology" companies reached a record $2 billion in the second quarter, paced by investments in solar technologies and second-generation biofuels, according to a report out today from Cleantech Group LLC. Investments jumped 58 percent from the second quarter last year and 48 percent from the first quarter this year. The previous record was the 2007 third quarter at $1.8 billion.

The latest quarter's growth in cleantech investments by venture capital firms, investment banks and other investors contrasts with a projected decline in overall venture investments during the same period, the company said.

Solar-thermal companies including eSolar, BrightSource Energy, SkyFuel, Infinia and Sopogy raised a total of $278 million in venture capital in the second quarter.

Second-generation biofuel companies such as Range Fuels, Sapphire Energy, EdeniQ, Mascoma, Aurora BioFuels, Gevo, Fulcrum Bioenergy, Greenline Industries, GreenFuel Technologies and Amyris Biotechnologies raised $280 million in venture investment in the period. Of the total, $136 million went to cellulosic ethanol startups and $84 million in algae biomass startups.

"For the first time, algae companies are attracting large, follow-on investment rounds--a trend we expect to continue into the second half of the year," said Brian Fan, senior director of research for the Cleantech Group. "This breakout quarter for solar thermal and algae companies indicates a growing appetite for clean technologies that can replace coal for electricity generation and oil for transportation fuels."

U.S. companies took 74 percent of the investments, Europe 13 percent, and China and India 12 percent. The leading venture investors were Kleiner Perkins Caulfied & Byers, Foundation Capital, Quercus Trust, Khosla Ventures, and Draper Fisher Jurvetson.