灰黄青霉生物染色对毛竹性能影响的研究

Effects of Penicillium griseofulvum’s biological dyeing on the properties of Phyllostachys heterocycla

【目的】竹材变色现象普遍发生,但针对其这一特质的功能性开发仍然不足。利用竹材易发生生物变色的特性,可以诱导灰黄青霉侵染毛竹来实现竹材的生物染色。【方法】通过真菌培养、接种与侵染、灭菌干燥等步骤制备得到灰黄青霉侵染后的毛竹;通过SEM、ATR-FTIR、表面色差测试、表面接触角测试、表面粗糙度测试、质量损失率测试、24 h吸水率测试和力学强度测试来分析灰黄青霉侵染行为对毛竹的微观形貌、化学组分、表面性能和物理力学性能的影响。【结果】灰黄青霉分泌的红褐色渗出液累积并渗透附着于竹材表层;灰黄青霉菌丝由维管束中的导管进入毛竹内部蔓延生长,并在毛竹内部产生色素;纤维素、木质素的降解和半纤维素的轻微降解主要发生在侵染前期;侵染行为使毛竹表面色差值不断增大,色调逐渐转变为暗红,形成独特的装饰效果,同时表面接触角变小,表面粗糙度无明显变化;侵染行为对毛竹的物理力学性能影响较小,质量损失率略有升高,24 h吸水率下降,力学性能的下降主要发生在侵染的10~20 d。【结论】证明了竹材生物染色在不严重影响竹材性能的同时能取得较好的染色效果,为竹材生物染色技术进一步的研究提供了基础和理论依据。

[Objective] Discoloration of bamboo is common. However, the functional development for this feature is still insufficient. The discoloration of bamboo affects the use value and economic value of bamboo and its products. At present, the research on biological discoloration of bamboo is mainly aimed at prevention and control. In this study, the biological dyeing of bamboo was realized by inducing Penicillium griseofulvum to infect bamboo, which is easy to change color. [Method] The bamboo infected by P.griseofulvum was prepared by fungal culture, inoculation, infection, sterilization and drying;the effects of P.griseofulvum infection on the micromorphology, chemical components, surface properties, physical and mechanical properties of Phyllostachys heterocycla were analyzed by SEM, ATR-FTIR, surface color difference test, surface contact angle test, surface roughness test, mass loss rate and 24 hours water absorption, mechanical strength test. [Result] The red exudate secreted by P. griseofulvum accumulated and permeated to the surface of Phyllostachys heterocycla. P. griseofulvum entered, spread, grew and produced pigment in the interior of bamboo through vessel cells in bamboo vascular bundles. The degradation of cellulose, lignin and hemicellulose mainly occurred in the early stage of infection. The infection behavior made the surface color difference value of Phyllostachys heterocycla increased continuously, the color changed to dark red gradually, forming a unique decorative effect. At the same time, the surface contact angle became smaller, and the surface roughness had no obvious change. The influence of infection behavior on the physical and mechanical properties of Phyllostachys heterocycla was small, the mass loss rate was slightly increased, the water absorption rate decreased in 24 hours, and the decrease of mechanical properties mainly occurred in 10-20 days of infection. [Conclusion] This study proves that the biological dyeing of bamboo can achieve better dyeing effect and has no serious adverse effects to bamboo properties, which provides the theoretical basis for further research of biological dyeing technology of bamboo.