Lulu, who led out the country's five-strong Olympic team at the opening ceremony, was carrying the support of the ExCel Arena crowd against Ligia Silva.
Yet she was unable to overcome the Brazilian, with her exit sealed in a 4-0 defeat.
That was one of three straight games victories in the opening session, in which Canada's Mo Zhang brushed aside Qatar's Aia Mohamed, while Cameroon's Sarah Hanffou wasted little time in cruising past Libya's Tvin Moumjoghlian.
The other morning encounter was an early contender for match of the day.
Neda Shahsavari, Iran's first female table tennis Olympian, twice came from behind against Nigeria's Olufunke Oshonaike, only to lose the decider 11-3.