<?php
$re = '/\s*#[^:]+:\s*/';
$str = '#Jhon: Manager #Mac: Project Manager #Az: Owner';
$res = preg_split($re, $str, -1, PREG_SPLIT_NO_EMPTY
);
PD9waHAKCiRyZSA9ICcvXHMqI1teOl0rOlxzKi8nOwokc3RyID0gJyNKaG9uOiBNYW5hZ2VyICNNYWM6IFByb2plY3QgTWFuYWdlciAjQXo6IE93bmVyJzsKJHJlcyA9IHByZWdfc3BsaXQoJHJlLCAkc3RyLCAtMSwgUFJFR19TUExJVF9OT19FTVBUWSk7CnByaW50X3IoJHJlcyk7