Retrieve All Files Separated by Comma from Server Using Curl

I want to retrieve all file names from a server using Curl into a variable. But my main issue is that I was all the file names to be separated by a comma.

Files Present in FTP : file 1.txt , files 10 11 .txt, orange to orange.txt

My Command :

file_list=$(curl -l --silent -u ${Username}:${Password} --ssl-reqd ftp://${Server_URL}/Path/ --insecure) 

Above Command Return Value : file 1.txt files 10 11 .txt orange to orange.txt

Value I want : file 1.txt , files 10 11 .txt , orange to orange.txt

Using above values I want to transfer all files from Server to my System.