The 27-year-old Prakash's gold-medal winning time of 1 minute 57.85 seconds was his season's best but slower than the Tokyo Olympics 'A' qualification standard of 1 minute 56.48 seconds.
In February, he had clocked 1 minute 59.31 seconds in Latvia. In 2019, he clocked 1 minute 58.03 seconds in Malaysia.
Six Indians, including Prakash, had achieved Olympic 'B' qualification time in 2019.
The 'B' qualification time doesn't guarantee an automatic berth for the Olympics. The 2020 season was disrupted by pandemic and as swimming competitions resumed this year, all the six swimmers are chasing the 'A' cut time in their respective events.
The other Indians, who won medals in Tashkent on Tuesday, weren't even close to Olympic 'B' qualification time.
Anand AS won bronze in the 100m freestyle clocking 51.95 seconds. Adhitya D, the second Indian in fray was fourth with a time of 52.07 seconds.
Kenisha Gupta won gold medal in the women's 100m freestyle event with a time of 57.42 seconds, while Shivani Kataria who had represented India in the 2016 Rio Olympic Games got bronze with a time of 59.6 seconds.