This may be what you want if you are sure the time string format won't change too much:
my ($time, $minute) = $string =~ /,(\d\d:(\d\d):\d\d)/g;
use strict;
my $string="01:01:2000,14:01:12,1.584167";
my ($time, $minute) = $string =~ /,(\d\d:(\d\d):\d\d)/g;
print "TIME: $time\nMINUTE: $minute\n";