A sustainable method for the preparation of durable, biologically non-toxic anti-mildew bamboo

Abstract

Moso bamboo possesses the features of fast growth, high mechanical strength and environmental friendliness, but its application is limited due to its susceptibility to fungal infection. In contrast, the reported anti-mildew strategies have the technical bottleneck of easy loss and high toxicity of anti-mildew agents. This work shows an efficient strategy for obtaining a stable, biological, non-toxic anti-mildew bamboo. Selective oxidation methods were used to obtain dialdehyde cellulose (DAC) on the bamboo surface, to achieve dialdehyde groups, which were efficient for anti-fungal infection. The modified bamboo's micro-structure, anti-mildew, stability and cytotoxicity were investigated by setting the ratios of NaIO₄ to bamboo. The optimal mildew resistance achieved when the ratio of NaIO₄ to bamboo was 5 % (B@5 %), displaying a durable anti-mildew performance, of which the Aspergillus niger control efficiency of 100 % after 30 days of anti-mildew test. The B@5 % can resist 200 times of mechanical friction and maintain 50 % anti-mildew efficiency, showing excellent chemical stability under different pH conditions. More importantly, B@5 % has no toxic damage to cells in vitro. The above outstanding properties show that the modified bamboo has great potential in industrial and food-grade mildew-proof bamboo.