Mumbai: The BSE benchmark Sensex lost nearly 47 points in opening trade on Thursday, tumbling for the sixth straight session as funds and investors offloaded positions in knee-jerk response to India Inc's poorer-than-expected second quarter corporate earnings.

A weakening trend in global markets on lingering concerns over the euro zone debt crisis also dampened the trading sentiment here.

 The 30-share Sensex, which has lost 793 points over the past five sessions, fell further by 46.64 points, or 0.28 per cent, to 16,729.23 in opening trade on Thursday, with capital goods, auto and IT stocks leading the fall.

In a similar fashion, the wide-based National Stock Exchange Nifty index declined by 12.60 points, or 0.25 per cent, to 5,017.85.

Brokers said the investor sentiment remains depressed as the second quarter earnings posted by corporates were below the market expectations.

 A weakening trend in global markets on worries about the euro zone debt crisis also influenced selling by funds, they said.

Hong Kong's Hang Seng index was down by 1.45 per cent, while the Japanese Nikkei shed 0.32 per cent in morning trade on Thursday. The Dow Jones Industrial Average in the US ended 1.58 per cent lower in Wednesday’s trade after ratings agency Fitch warned that US banks could be hit hard by the euro zone crisis.