Effects of extraction methods on anti-mould property of bamboo strips

Abstract

To achieve improvements in anti-mould properties, bamboo strips were subjected to extractions with different combinations of extraction media: boiling water, 1.0 wt.% hydrochloric acid (HCl), or 1.0 wt.% sodium hydroxide (NaOH). The impacts of different extraction methods on the structure and anti-mould properties of bamboo strips were investigated. The results suggested that bamboo strips treated alternatively with different extraction media were free of changes in crystalline structure and cell morphology but showed partial degradations of hemicellulose and decreases in the amount of free hydroxyl groups. As a result of these treatments, elimination or migration of extractives (including starch, soluble saccharides, and aliphatics) improved the resistance of bamboo strips to Penicillium citrinum, Trichoderma viride, Aspergillus niger, and a mixture of these mildews. Among the tested treatments, sequential extraction with boiling water, 1.0 wt.% NaOH, and 1.0 wt.% HCl resulted in a mildew-preventing efficiency of 96.9%, indicating optimum anti-mould properties.