Chemical makers BRAIN and CyPlus said this week scaled up (from 100 litres to one tonne) testing of "market-relevant products for the global mining industry" showed its bio-based production process was nearly ready for industrial application.

Extraction of precious metals from the ores was based on the use of naturally occurring and enhanced microorganisms from BRAIN BioArchives, the former said.

The partners have filed a patent for the bio-based method - with the filing describing the microorganisms and their selectively adhesive properties that can be used to "enrich precious metals from ores".

"We're delighted - and proud - that the BRAIN and CyPlus interdisciplinary team has succeeded in establishing a ground-breaking biological process for a new processing technology and developing it to high product maturity in just a few years," said BRAIN board member, Dr Guido Meurer.

"With our processes for green mining it will be possible in the future to exploit ore deposits containing precious metals even in regions where the conventional processes are out of the question. Green mining is an increasingly important issue and an attractive field of business also in view of the increasing scarcity of raw materials."

Stefan Welbers, senior vice president of CyPlus, said he hoped to be able to offer mine operators the option of integrating advanced biotechnological methods into current processes "without significant investment costs or delays in operation".

"In this way, we're expanding our technology portfolio to include biological components for efficient and eco-friendly processing of precious metals," he said.