Context :

Aims : With the aim of assessing the effects of bars on disc galaxy properties , we present an analysis of different characteristics of spiral galaxies with strong , weak and without bars .

Methods : We identified barred galaxies from the Sloan Digital Sky Survey ( SDSS ) .
By visual inspection of SDSS images we classified the face-on spiral galaxies brighter than g < 16.5 mag into strong-bar , weak-bar and unbarred .
With the goal of providing an appropiate quantification of the influence of bars on galaxy properties , we also constructed a suitable control sample of unbarred galaxies with similar redshift , magnitude , morphology , bulge sizes , and local density environment distributions to that of barred galaxies .

Results : We found 522 strong-barred and 770 weak-barred galaxies , which represent a bar fraction of 25.82 \% , with respect to the full sample of spiral galaxies , in good agreement with several previous studies .
We also found that strong-barred galaxies show lower efficient in star formation activity and older stellar populations ( as derived with the D _ { n } ( 4000 ) spectral index ) , with respect to weak-barred and unbarred spirals from the control sample .
In addition , there is a significant excess of strong barred galaxies with red colors .
The color-color and color-magnitude diagrams show that unbarred and weak-barred galaxies are more extended towards the blue zone , while strong-barred disc objects are mostly grouped in the red region .
Strong barred galaxies present an important excess of high metallicity values , compared to unbarred and weak-barred disc objects , which show similar 12 + log \left ( O / H \right ) distributions .
Regarding the mass-metallicity relation , we found that weak-barred and unbarred galaxies are fitted by similar curves , while strong-barred ones show a curve which falls abruptly , with more significance in the range of low stellar masses ( log ( M _ { * } / M _ { \sun } ) < 10.0 ) .
These results would indicate that prominent bars produced an accelerating effect on the gas processing , reflected in the significant changes in the physical properties of the host galaxies .

Conclusions :