Get-SCVMHost -VMMServer localhost | Select -Property @{name='BIOSGUID';expression={$_.PhysicalMachine.SMBiosGUID}} | convertto-json -depth 4

[
    {
        "BIOSGUID":  null
    },
    {
        "BIOSGUID":  {
                         "value":  "xxxyyyzzz",
                         "Guid":  "xxxyyyzzz"
                     }
    },
    {
        "BIOSGUID":  {
                         "value":  "yyyzzzaaa",
                         "Guid":  "yyyzzzaaa"
                     }
    }
]