When I use this script:
Get-DistributionGroup -Filter {Displayname -like "DG_Group"}|Select managedBy|ft
I get the OU together with the Name, Output:
{work.place/EUR/User/Surname, FirstName}
But I only want the Name, example Output:
{Surname, FirstName}
If all you want returned is the last part of whatever is in the ManagedBy (multivalue) property, try this (untested):
Get-DistributionGroup -Filter 'Displayname -like "DG_Group"' |
Select-Object Name,
@{Name = "ManagedBy"; Expression={($_.ManagedBy | ForEach-Object {$_.Split("/")[-1]})}}