Consider using Email::Address:

use Modern::Perl;
use Email::Address;

my $x         = 'jdoe@somewhere.com,bdoakes@nowhere.com';
my @addresses = Email::Address->parse($x);

say for @addresses;
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Output:

jdoe@somewhere.com
bdoakes@nowhere.com
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Update: Didn't notice that Anonymous Monk already covered this. I really do need more coffee...