Private equity group 3i is to buy debt management business Mizuho Investment Management (UK).3i has entered into an agreement with Mizuho Corporate Bank (MHCB) to purchase 100% of the shares in business Mizuho Investment Management (MIM) for an enterprise value of £18.3 million.MIM specialises in the management of funds raised to invest in senior and subordinated corporate debt, providing investment advisory services in return for fees. It employs 28 employees, has raised eight funds, totalling over £4.0bn since 2005 and had £3.7bn of assets under management (AuM) at 31 March 2010.3i's existing debt management activities will be merged with MIM to form a distinct business line, 3i Debt Management (3i DM), with a total AuM of around £4.0bn. Jeremy Ghose, chief executive officer (CEO) of MIM will become Managing Partner and CEO of 3i DM and will join 3i's leadership team. "There is an excellent cultural fit with 3i and the expanded business will create an enhanced debt platform to grow profitably into the future," said 3i's group CEO, Michael Queen.On completion of the acquisition, MIM management and 3i's existing debt management team will invest in 3i DM to acquire a 45% stake, and 3i will retain the 55% majority interest.3i and management intend to grow 3i DM through further acquisitions and raising new funds.