Oil markets dominated focus around the close, as crude prices rallied over 2 percent, with investors shrugging off a surprise build in U.S. inventories. At the close, Brent crude was trading at $52.46 a barrel, while U.S. crude was up at $48.85.
Oil companies tried to remain positive on this, with Royal Dutch Shell and Sbm Offshore ending in the green, but most stocks closed in the red with Seadrill down 5.3 percent and Statoil off 3.2 percent.
In individual stock news, shares in Deutsche Bank slipped down 1.8 percent after the bank said it was bracing for a loss before taxes of 6 billion euros ($6.7 billion) in the third quarter due to massive writedowns at its investment banking unit and on the value it expects to extract from the divestment of its Postbank retail bank, Reuters reported Wednesday.
Credit Suisse tanked as much as 4.7 percent after a report in the Financial Times suggesting the bank is preparing to launch a "substantial capital raising" on October 21. Chief executive Tidjane Thiam told CNBC in July that it "may need" fresh capital to help address its issues. Shares in the bank have now closed down 3.6 percent.