Вы можете использовать str.split
s
Out[417]:
0 Tuscaloosa (University of Alabama >> Tuscaloosa
0 Tuscaloosa (University of Alabama >> Tuscaloosa
0 Tuscaloosa (University of Alabama >> Tuscaloosa
0 Tuscaloosa (University of Alabama >> Tuscaloosa
dtype: object
s.str.split('(',1).str[0]
Out[418]:
0 Tuscaloosa
0 Tuscaloosa
0 Tuscaloosa
0 Tuscaloosa
dtype: object