If you aren't scared of using jQuery and JS: 
, here's a crazy method:
var labels = $(".v-m-xAxis .viz-axis.v-axis .viz-axis-body.v-body .v-label.viz-axis-label.v-morphable-label > text");
for(var i=0;i<labels.length;i++){
var seperator = ','; // Adjust to fit locale
label = labels[i].textContent = labels[i].textContent.replace(
new RegExp(seperator,'g'),'');
}