FRUITFUL STUDY: Scientists work to extract human serum albumin from rice (CHENG MIN)

Throwaway tableware used at the 2010 World Expo site is made of biomass "plastics" from corn, which has zero environmental pollution. "Signs, badges and magnetic cards used during the Expo could also be made of biomass materials," said Professor Ren Jie from the School of Materials Science and Engineering of Shanghai-based Tongji University.

Ren said his team uses corn and other crops to produce polylactic acid (PLA) through fermentation and other preparation. It is then made into different kinds of PLA products that degrade after being used—without leaving any pollution. "We can produce such environmentally friendly products in large quantities," said Ren.

Plasma from rice

BIOENERGY TREES: Scientists observe plants used to produce diesel oil in southwest China's Yunnan Province (CHEN HAINING)

Wuhan University, based in central China's Hubei Province, recently announced, following four years' research, a team led by Professor Yang Daichang of the College of Life Sciences had successfully extracted human serum albumin (HAS) from rice.

HAS, accounting for 30 percent of human blood plasma, is used to treat hemorrhagic shock, cerebral and renal edema, and hepatic ascites, in rehydration of burn victims and as adjunct therapy in cancer and AIDS patients. Since HAS is widely used in clinical treatment, the annual demand for it in China amounts to between 150 and 170 tons, which used to be totally extracted from blood plasma. The blood to produce enough HAS equals donations of 100 milliliters of blood each year by 200 million people. Since there is not enough donated blood, the demand-supply gap of HAS in China is between 60 to 80 tons every year.

"The shortage of blood plasma is a worldwide problem. Many countries try to use biological technologies to produce and recombine HAS besides extracting it from blood plasma," said Yang. Technology developed by his team can extract 1,000 kg of HAS from rice of about 33 hectares of land.

Explaining why rice was chosen, Yang said rice is a self-pollinating crop with low biosafety risks. "In addition, China's transgenic technology on rice is well developed, and its biological studies on rice are also advanced."

Yang's team uses rice endosperm as "units" of protein production and introduces the genes of HAS into a rice genome to produce a new rice variety. "As the rice seeds grow, HAS also grows through synergy and accumulation. When the rice is ripe, it is ready for the extraction of HAS."

HAS extracted from human blood plasma always entails the risk of carrying viruses, which HAS from rice endosperm eliminates, but its molecular characteristics are identical to those of blood plasma HAS. "HAS from rice has better curative efficacy and molecular activity," said Yang.

Currently, his team has obtained recombinant HAS of high purity, and its quality surpasses similar products from other countries. The team is working with a Wuhan-based biological hi-tech company to develop products for the international industrial reagents market. The cooperative program expects to launch pharmaceutical products containing recombinant HAS in four or five years.

"As long as it passes China's drug safety evaluation, it could completely replace blood plasma HAS," said Yang.