The development of nanofibrous scaffolds containing biological agents is necessary to provide adequate conditions for tissue regeneration and to prevent the recurrence of cancer after surgical operations. Here we fabricated nano fibers composed of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), dextran, laminarin, hydrolyzed dextran, and hydrolyzed laminarin using an electrospinning process. The resulting nanofibers exhibited a fully interconnected pore structure. The water contact angles were reduced by the addition of low molecular weight glucans. The results from cell viability tests showed that the proliferation rate of melanomas on the nanofibers fabricated with 8:2 of PHBV and hydrolyzed laminarin (PHHL) was significantly suppressed by increased TNF-alpha secretion. However, the proliferation of skin fibroblasts on the PHHL nanofibers was effectively stimulated because of the antioxidant activity and hydrophilicity of hydrolyzed laminarin.