A WORLD Bank unit on Wednesday said it has joined 16 other investors in the largest equity venture ever established for Africa, a $400-million fund to support private sector infrastructure projects. The International Finance Corporation (IFC), an arm of the World Bank that finances private sector investment in developing countries, will contribute $75-million to the fund, with an equal amount provided by the US-based insurers American International Group. The other main contributors are the African Development Bank, the Development Bank of Southern Africa, a unit of the French development agency and international investor Sheikh Mohammed Al-Amoudi.