Growth of Z. bailii in laboratory media at 25°C in the presence of native chitosan (□) and hydrolyzed chitosan at concentrations of 0.1 g/liter (A), 0.2 g/liter (B), and 0.3 g/liter (C). The viscosities of the hydrolysates were 154 s (■), 96 s (▴), 54 s (▵), 11 s (●), and 0 s for the control containing N-acetylglucosamine plus hydrogen peroxide (○). The hydrolysates were prepared by the oxidative-reductive degradation method. The results are means based on five replicate values for absorbance at 620 nm (A620). Bars indicate standard error.