using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

            string source = "(<email1@test.com>; <email2@test.com>; <email3@test.com>, <email4@test.com>; <email5@test.com>; \r\n\t<email6@test.com>, <email7@test.com>; <email8@test.com>\r\nTEXT)";

            Regex regx = new Regex(@"(<)(\w+@\w+\.\w+)(>)");

​

            MatchCollection matches = regx.Matches(source);

            foreach (Match match in matches) {

                Console.WriteLine(match.Groups[2].Value);

            }

​

    }

}