12 seconds.
Russian Anastasia Zueva won the silver medal in a time of 58.18, while Australian Emily Seebohm was the bronze medal winner in 58.88.
Alessia Filippi was a popular winner in the women's 1,500m freestyle as she came from behind to give Italy the gold medal in a championship record time of 15:44.93.
Denmark's Lotte Friis, who looked on world record course for the first 600m, finished second, in a time of 15:46.30, while Romanian Camelia Alina Potec won the bronze in 15:55.63.
At the end of her swim Filippi took a bow as the crowd gave her a standing ovation while they were chanting her first name.
South African Cameron Van den Burgh, who Monday won a bronze medal in the men's 100m breaststroke, managed to break Felipe Franca da Silva's world record in the men's 50m breaststroke semi-finals.
Van den Burgh had a time of 26.74, beating the Brazilian's time of 26.89 by .15 seconds.
Da Silva finished with the third-best time of 26.92, while Germany's Hendrik Feldwehr had the second-fastest time in 26.83.
The final of the men's 100m backstroke as well as the women's 100m breaststroke will be held later Tuesday.