U.S. chemical manufacturing group E. I. du Pont de Nemours &o. extended its $6 billion takeover bid for Danisco A/S by four weeks after holders of only 6 percent of the Danish company’s shares had accepted the offer. DuPont said the offer was extended to April 29 to provide more time to get regulatory approvals from China and the European Union, the absence of which some say could be restraining the offer uptake. Analysts said this week that market turmoil in the wake of crises in the Middle East and Japan would make DuPont increasingly disinclined to raise its bid, while at the same time many Danisco shareholders were holding out for more money.