use Unicode::MapUTF8 qw(to_utf8 from_utf8);
...
#convert into utf8 
$str = to_utf8({ -string => 'Your string here', -charset => 'ISO-8859-1' });
# TODO: insert into DB
.....
# TODO: select stuff from database, and then
$str =  from_utf8({-string => $str_retrieved, -charset => 'ISO-8859-1'});

# TODO: now check the value of $str