Gauged supergravity algebras from twisted tori compactifications with fluxes

Using the equivalence between Scherk-Schwarz reductions and twisted tori compactifications, we discuss the effective theories obtained by this procedure from M-theory and N =4 type II orientifold constructions with Neveu-Schwarz and Ramond-Ramond form fluxes turned on. We derive the gauge algebras of the effective theories describing their general features, in particular the symplectic embedding in the duality symmetries of the theory. The generic gauge theory is non-abelian and its gauge group is given by the semidirect product of subgroups of SL(7) or SL(p-3) x SL(9-p) for p=3,...,9, with generators describing nilpotent subalgebras of e_{7(7)} or so(6,6) (in M and type II theories respectively).