use strict;
use warnings;

while (<DATA>)
{
    print ">$1<\n" if / ^ \s* Fruits? \s* \{ \s* (.*?) \s* \} /x;
}

__DATA__
Fruits{ Apple Mango Grape Watermelon }
Fruit{ Apple }
Fruits{ Lemon Mandarin }{ Orange Fig Pineapple }
Vegetable{ Carrot }