Private equity group Bridgepoint has hired Morgan Stanley to sell Aenova, hoping to get more than €400 million ($510 million) for the German vitamins and generic prescription drugs maker, two people familiar with the situation said.

Aenova is set to join a growing list of medium-sized German businesses going up for sale as private equity groups trawl their portfolios looking for strong disposal candidates.

An auction for Aenova is planned for the autumn, the people said, and is expected to attract rival vitamin makers such as German chemicals group BASF and Dutch supplements maker DSM, as well as private equity firms.

Other private equity-backed businesses on the block in Germany or expected to go up for sale include bandages maker BSN Medical, power transformer group SGB Starkstrom and heavy machinery manufacturer Gienanth.

Resilient demand for good-quality businesses and a recovery in debt markets is stoking sellers' hopes that they can achieve good prices.

Aenova, which has ten sites across Europe and the United States and employs about 1,600 people, is targeting earnings before interest, tax, depreciation and amortisation (EBITDA) of about €50 million in 2012.

The group recorded EBITDA of €43.2 million in 2011 and sales of 262 million.

Aenova was formed by Bridgepoint through the merger of Swiss Caps, a maker of soft capsule vitamins, supplements and pharma products, with Dragenopharm, a German contract manufacturer for the prescription drugs market.

Bridgepoint was unavailable for comment. Aenova and Morgan Stanley declined to comment.