It is well known that the Michelson-Sivashinky equation describes hydrodynamic
instabilities in turbulent premixed combustion. Here a formulation of the flame
front propagation based on the G-equation and on stochastic fluctuations imposed
to the average flame position is considered to derive the Michelson-Sivashinky
equation from a modelling point of view. The same approach was shown to
reproduce the G-equation along the motion of the mean flame position, when the
stochastic fluctuations are removed, as well ast the Zimont & Lipatnikov model,
when a plane front is assumed. The new results here presented support this
promising approach as a novel and general stochastic formulation for modelling
turbulent premixed combustion