By Guillermo Parra-Bernal and Silvio Cascione

SAO PAULO, Nov 27 (Reuters) - Brazilian stocks dropped on Friday for a second day, in line with global equity markets, as a possible debt default at a Dubai state-owned conglomerate sparked fears of renewed global financial turmoil.

Commercial banks, steelmakers and commodity exporters led declines in the benchmark Bovespa index .BVSP, which shed 0.5 percent to 66,049.91 and came on top of a 2.3 percent tumble on Thursday. Fifty-four stocks tumbled while only eight rose on on Friday's session.

Dubai's announcement on Wednesday that it would attempt to reschedule debt payments of its Dubai World commercial real estate unit will spur significant corrections in the prices of emerging markets assets while casting more doubts over the sustainability of a global recovery, investors said.

"Investors have done so well in Brazil this year that this is the kind of situation that makes people want to reduce their risk in general," said Urban Larson, who manages about $2 billion in emerging market stocks for F&C Investments in London.

Brazil is mainly a commodity exporter that has benefited this year from rising prices of iron ore, oil and produce including beef, soybean and orange juice. But a default by Dubai may put those gains at risk and thwart a recovery in the global economy, he said.

Commercial lenders fell, pushing the Bovespa to its lowest level since Nov. 13. Investors are concerned global financial firms in Europe and Asia are exposed to Dubai's woes, hampering the outlook for the future of the industry across the world, said one trader who declined to be quoted by name.

Itau Unibanco (ITUB4.SA: Quote, Profile, Research), the nation's largest nongovernmental bank, led the Bovespa drop after tumbling 1 percent to 37.16 reais. Banco do Brasil (BBAS3.SA: Quote, Profile, Research), Latin America's largest bank, fell 0.8 percent to 29.94 reais.

Losses in Banco do Brasil were eased after Reuters reported that the Brasilia-based lender is seeking to buy a regional lender in the United States and expand into Argentina, Chile, Colombia and Peru. [ID:SPG002611]