You could a `sed` to first remove the pattern containing `ent` and then put the spacing away and replace it with `,` as
sed 's/ent[0-9][0-9]: //g; s/ /,/g'
You could a `sed` to first remove the pattern containing `ent` and then put the spacing away and replace it with `,` as
sed 's/ent[0-9][0-9]: //g; s/ /,/g'