Antifungal activity of nano and micro charcoal particle polymers against Paecilomyces variotii, Trichoderma virens and Chaetomium globosum

•Mycelial growth of P. variotii, T. virens and C. globosum was suppressed by charcoal polymers.•Protrusion of nano and micro sized charcoals were found on polymer surfaces.•Adsorption of Ca2+ by charcoals on polymer caused the inhibition of mycelial growth.•Nano-sized pores in charcoals were thought to participate in Ca2+ adsorption.