New Delhi, Nov. 4: A human blood protein widely used in medicine may someday be harvested from rice farms if a biotechnology protocol developed by Chinese scientists makes its way from their laboratory into the market.

Chinese researchers announced on Monday that they have found a way to produce large amounts of a protein called human serum albumin (HSA) from rice seeds genetically-engineered to serve as tiny biological factories.

Their experiments suggest that rice seeds may be used for cost-effective production of HSA, a protein currently extracted from human blood and used to treat haemmorhagic shock, burn injuries, liver cirrhosis and other conditions.

Genetically-engineered rice may help satisfy a growing worldwide demand for HSA, Daichang Yang, a professor of plant biotechnology at the College of Life Sciences at Wuhan University and his colleagues said, describing their results in the US journal Proceedings of the National Academy of Sciences.

Several research groups have earlier produced HSA from bacteria, yeast, potato and tobacco leaves. But, according to Yang and his team members, these earlier efforts have not proven to be cost-effective for large-scale production.

Their protocol allows them to extract 2.75 grams of HSA per kilogram of brown rice, an amount, they said, is much higher than the cost-effective threshold of 0.1 grams per kilogram for the production of HSA from plants.

The scientists said the HSA from rice is biochemically and structurally equivalent to HSA derived from blood. In one set of laboratory tests, the scientists treated rats with induced liver cirrhosis and observed that the HSA from rice achieved similar results as were obtained in rats treated with HSA derived from blood.

Biotechnology experts say that while the HSA production protocol appears promising, the use of HSA from rice will depend on how closely the molecule derived from rice mimics the molecule from blood.

“Will this become a substitute HSA from (blood) plasma? We’ll have to wait and see,” said Suresh Vyas, a professor of pharmaceutical biotechnology at the Harisingh Gour Vishwavidyalaya in Sagar (Madhya Pradesh), who was not associated with the project but is familiar with attempts to make therapeutic proteins from plants.

Yang told The Telegraph that it could take five to seven years to further refine the technology and evaluate the HSA for medical applications. In addition to treatment for various conditions, HSA is also used in the production of medicines and vaccines.

The researchers estimate that the worldwide market for HSA is more than 500 tonnes per year.

A US company Ventria Bioscience Technology has described itself as the first company to commercialise proteins from a plant-based manufacturing system. It is using rice and barley as production hosts to produce albumin and three other proteins.