You need StripMtext dialog box routine that strips internal formats from Mtext.
StripMtext can remove the following types of formatting:
Alignment
Background Masks
Color
Columns
Fields (converts fields to static text)
Font
Height
Line Feed (newline, line break, carriage return)
Non-breaking Space
Obliquing
Overline
Paragraph (embedded justification, line spacing, indents)
Stacking
Tabs
Tracking
Underline
Width
Look for new stable releases at:
http://cadabyss.wordpress.com/
More information may also be found at:
https://www.theswamp.org/index.php?topic=31584.0
http://www.theswamp.org/ Subforum: "Show your stuff", Subject: "StripMtext v5"
Works for tables as well.