This work demonstrates a unique approach of utilizing alkali lignin (AL), as smart additive to in situ BC fermentation in which it concurrently acts as promoter to microbial growth as well as reinforcing filler for fabrication of multifunctional composites. Traditionally, BC fermentation is accompanied by inhibitor formation with sudden drop in pH leading to low yield and biomass growth. AL due to its antioxidant nature prevents formation of gluconic acid as byproduct, at ∼0.25 wt.% AL based on inhibitory byproduct kinetics. Interestingly, AL self-assembles to form primary and secondary structures in BC pores, resulting in simultaneous improvement in thermal stability as well as toughness. The BC/AL films show strong UV-blocking capacity with prolonged radical scavenging activity and preventing browning of freshly cut apples making it suitable as food packaging. Therefore, present work opens up new avenues for fabrication of high-performance BC-based composites through selection of smart materials which can simultaneously improve BC bioprocessing.

这项工作展示了利用碱木质素（AL）作为原位智能添加剂的独特方法BC发酵，在此过程中，它同时充当微生物生长的促进剂以及增强多功能复合材料制造的填充剂。传统上，BC发酵伴随着抑制剂的形成，pH值突然下降，导致产量低和生物量增长。由于其抗氧化性质，AL抑制了作为副产物的葡萄糖酸的形成，基于抑制性副产物的动力学，AL含量约为0.25 wt。％。有趣的是，AL自组装以在BC孔中形成一级和二级结构，从而同时提高了热稳定性和韧性。BC / AL膜具有很强的紫外线阻隔能力，具有延长的自由基清除活性，并且可以防止新鲜切碎的苹果褐变，使其适合用作食品包装。因此，