Biomanufacturing technique cuts cost of extracting omega-3 from microalgae

Omega-3 oils have known health benefits, but are typically found in fish, making them unsuitable for vegetarians and increasing the pressure on already limited fish stocks.

Microalgae offer an alternative source of omega-3, but extracting the oils from the organisms has so far proven expensive. That is because separating the algal biomass from water is extremely difficult, as membranes tend to get clogged, leaving manufacturers to resort to energy intensive centrifuges, according to Dr Adrian Stevenson, technical director at consortium lead LabXero, and group leader of the Acoustic Wave Physics group at Cambridge University.

“With a centrifuge you have a large drum, and you add your batch of algae from the bioreactor, and then spin it at [high] speed,” said Stevenson. “Centrifuges burn quite a lot of power and take quite a bit of time.”

Instead LabXero is developing a process known as acoustic cell harvesting technology, which consumes considerably less energy.

The technology is based on a filter, which can be incorporated into the fluidics, or plumbing, of the bioreactor itself, eliminating the need for a separate drum and thereby reducing the overall size of the operation, said Stevenson.