"Problem:- data save in database but not properly save.. i mean comma saparated values...."
That's where you are wrong!
Saving comma separated values in a database is a bad idea - it makes it very hard to work with when it comes to any significant changes. Think about trying to remove the "Silver" entry from this list:
"Silver Gold, Gold,Sterling Silver,Silver Brass"
in SQL, that's a PITA!
So if your DB has these stored in separate tables with foreign key links, than that's the right way! You don't show your table design, but converting a list of entries to a CSV in SQL is pretty easy:
SELECT SUBSTRING(
(SELECT ',' + MyValue FROM myTable
FOR XML PATH('')),2,100000) AS CSV