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We present a study of the optical nuclear spectra from the active galactic nuclei(AGN)in a sample of giant low surface brightness(GLSB)galaxies.GLSB galaxies are extreme late type spirals that are large galaxies that are usually isolated and poorly evolved compared to regular spiral galaxies.Though gas rich(HI),they have low star formation rates and massive dark matter halos.Earlier studies have indicated that their nuclei have relatively low mass black holes.Using data from the Sloan Digital Sky Survey(SDSS),we selected a sample of GLSB galaxies that showed broad Hα emission lines in their AGN spectra.We derived the nuclear black hole(BH)masses from their AGN emission lines; the nuclear BH masses lie in the range 105–107 M⊙.The bulge stellar velocity dispersion σ*,was determined from the underlying stellar spectra.We compared our results with the existing BH mass-velocity dispersion(MBH–σ*)correlations for active galaxies.We find that the majority of our sample lie in the low BH mass regime and below the MBH–σ* correlation.For galaxies having BH masses close to 107M⊙,the points lie closer to the MBH–σ* relation.This suggests that in the LSB galaxies,the black hole and bulge are not co-evolving.A possible explanation for the MBH–σ* offset seen in GLSB galaxies could be the lack of mergers and accretion events in the history of these galaxies.