df = pd.DataFrame([
        [(1, 2), (3, 4), (5, 6)],
        [(1, 2), (3, 4), (5, 6)],
        [(1, 2), (3, 4), (5, 6)],
    ])
print(df)

        0       1       2
0  (1, 2)  (3, 4)  (5, 6)
1  (1, 2)  (3, 4)  (5, 6)
2  (1, 2)  (3, 4)  (5, 6)

d2 = pd.DataFrame(np.array(df.values.tolist())[:, :, 1], df.index, df.columns)
print(d2)

   0  1  2
0  2  4  6
1  2  4  6
2  2  4  6

d2.sum()

0     6
1    12
2    18
dtype: int64

pd.Series(np.array(df.values.tolist())[:, :, 1].sum(0), df.columns)

0     6
1    12
2    18
dtype: int64