The benchmark Sensex turned choppy after surging over 200 points in early trade on Wednesday, ahead of US Federal Reserve’s policy outcome due later in the day amid mixed global cues. Investors were cautious ahead of the expiry of September derivative contracts on Thursday.The BSE 30-share barometer slipped in the negative terrain after advancing 200.76 points. It was trading 58.50 points, or 0.15 per cent, lower at 36,593.56.The gauge had gained 347.04 points in the previous session.The NSE Nifty fell 6.55 points, or 0.05 per cent, to 11,060.90. FMCG, oil and gas and IT stocks led the decline in the market. While, metal and pharma shares led the gainers’ pack.On Sensex, Wipro, ITC, HUL, ONGC, Kotak Bank, Maruti and Tata Motors were among the top losers, falling up to 2 per cent. On the other hand, Yes Bank emerged top gainer by rising 2.34 per cent after the board on Tuesday sought at least a three-month extension for MD and CEO, Rana Kapoor, from RBI beyond January 31, 2019. Other gainers include Tata Steel, M&M, Axis Bank, Sun Pharma, HDFC Bank, Bharti Airtel and HDFC, rising up to 1.73 per cent. Brokers said investor sentiment turned choppy on selling by foreign institutional investors (FIIs) ahead of the September month derivatives expiry on Thursday.Investors were also awaited policy cues from the US Federal Reserve, which is widely expected to raise interest rates, they added.On a net basis, domestic institutional investors (DIIs) bought shares to the tune of Rs 2,284.26 crore, while FIIs sold shares worth Rs 1,231.70 crore on Tuesday, as per provisional data. Elsewhere in Asia, Hong Kong’s Hang Seng was up 1.66 per cent, while Japan’s Nikkei rose 0.06 per cent in their early deals. Shanghai Composite index too gained 1.27 per cent.The US Dow Jones Industrial Average, however, ended lower by 0.26 per cent on Tuesday.