Three other top seeds -- second seeded Diana Marcinkevica of Latvia, third seeded Gioia Barbeiri of Italy and sixth seeded Jade Windley of Great Britain also lost their respective matches to crash out of the tournament.
Ankita, seeded fifth, raised hopes of registering an easy victory by clinching the opening set but here opponent -- Thai player Peangtarn Plipuech -- came back from a set down to win 4-6 7-6(7-5) 6-1 in two hours and five minutes.
Meanwhile, Great Britain's doubles specialist Anna Smith, currently ranked 572, registered one of the biggest upsets of the day when she defeated Marcinkevica (229) 1-6 6-3 6-3 in an hour and 55 minutes.
18-year-old Kamila Kerimbayeva of Kazakhstan, runners-up at the Pune event last week, stunned Barbeiri 6-2 6-1 in just an hour, while Armenian qualifier Ani Amraghyan registered another upset by beating Windley (310) 6-4 2-6 6-4.
In another second round match, top seeded Magda Linette of Poland stayed on course for the title by outplaying Thailand's Nungnadda Wannasuk 6-3 6-2 in an hour and seven minutes.