  We have derived ages, metallicities and enhanced-element ratios [alpha/Fe]
for a sample of 83 early-type galaxies essentially in groups, the field or
isolated objects. The stellar population properties derived for each galaxy
corresponds to the nuclear r_e/8 aperture extraction. The median age found for
Es is 5.8 +- 0.6 Gyr and the average metallicity is +0.37 +- 0.03 dex. For S0s,
the median age is 3.0 +- 0.6 Gyr and [Z/H] = 0.53 +- 0.04 dex. We compare the
distribution of our galaxies in the Hbeta-[MgFe] diagram with Fornax galaxies.
Our elliptical galaxies are 3-4 Gyr younger than Es in the Fornax cluster. We
find that the galaxies lie in a plane defined by [Z/H] = 0.99 log sigma_0 -
0.46 log Age - 1.60. More massive (larger sigma_0) and older galaxies present,
on average, large [alpha/Fe] values, and therefore, must have undergone shorter
star-formation timescales. Comparing group against field/isolated galaxies, it
is not clear that environment plays an important role in determining their
stellar population history. In particular, our isolated galaxies show ages
differing in more than 8 Gyr. Finally we explore our large spectral coverage to
derive log(O/H) metallicity from the N2 indicator and compare it with
model-dependent [Z/H]. We find that the O/H abundances are similar for all
galaxies, and we can interpret it as if most chemical evolution has already
finished in them.
