  We study the role of galaxy clusters in the mass-metallicity relation by
using a sample of galaxies belonging to the AC114 (z=0.317) galaxy cluster. The
data was taken from archival VIMOS-MOS spectroscopy to estimate gas-phase
metallicities by using strong-line methods. On the other hand, the data
obtained from DECaLS DR10 and VIKING DR4 ESO surveys were used to estimate
photometric masses. We found that passive galaxies dominate the population of
AC114 in the cluster center, whereas the star-forming members tend to be
located outside this region. The constructed MZR from the latter indicates that
AC114 SF galaxies have a lower metallicity content than foreground galaxies (z
up to 0.28) and the same or even lower metallicities with respect to background
galaxies (spanning redshifts 0.34 to 0.70), producing slightly a shallower
slope compared to the field MZR at z~0.3. Additionally, it shows a higher
scatter of 0.17 dex, consistent with MZRs of galaxy clusters reported in the
literature. The responsible mechanisms behind the scatter are consistent with
simulations and observations where dynamic and environmental effects such as
galaxy-galaxy interactions and ram-pressure stripping are shaping the chemical
evolution of the AC114 SF members. The former mechanism can decrease gas-phase
metallicities because of pristine gas infall to the galaxy's outskirts, and the
latter increases gas-phase metallicities because of the stripping of the
metal-poor gas located at the outskirts of the SF members. The AC114 SF members
are metal-poorer than field galaxies at the same redshift, so the cluster
dominated by galaxy-galaxy interactions is the best scenario that explains the
slightly shallower slope and the higher scatter of the AC114-MZR compared to
the field MZR at z~0.3.
