use warnings;
use strict;

my @record;

while (<DATA>)
{
	if (/^\d+\~/ && @record)
	{
		print join (" ", @record), "\n";
		@record = ();
	}
	
	chomp;

	push @record, $_;
}

print join (" ", @record), "\n";

__DATA__ 
99~Markus~Holli~Mobilenum:
1234-567 , from Earth
Europe
White
Human
98~Mahesh~Babu~Mobilenum:
5678-901 , from Earth
India
Brown
Human

##</code><code>##

99~Markus~Holli~Mobilenum: 1234-567 , from Earth Europe White Human
98~Mahesh~Babu~Mobilenum: 5678-901 , from Earth India Brown Human