We propose a simple extension of the standard model with lepton and baryon numbers gauged by introducing only two leptoquarks (j~(+1/2), k~(-1/2)) to the fermion content. As natural consequences of the anomaly cancelation, the right-handed neutrinos present and the number of observed fermion families equals to the number of fundamental colors, which is three. To avoid stabilized colored-leptoquarks, two scalar doublets φ, χ are introduced which couple the leptoquarks to ordinary quarks. The new gauge bosons Z_L, Z_B gain masses via the vacuum values of scalars S_L, S_B which are only charged under the U(1)_L, U(1)B symmetries, respectively. Furthermore, due to the spontaneous symmetry breaking of these charges, the neutrinos obtain small masses via type I seesaw mechanism while the baryogenesis can be generated in several cases. Constraints coming from flavor changing, stabilization of anomalously electric- charged scalars and collision phenomenology are also obtained.
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