Rajput Meenakshi, Pamecha Disha, Kumari Preeti, Chaturvedi Payal, Sharma Charu, Mishra Rahul, Chauhan Sunita
Department of Biotechnology and Microbiology, IIS (Deemed to be University), Jaipur 302020, India.
Kumarappa National Handmade Paper Institute (KNHPI), Jaipur 302011, India.
Curr Res Microb Sci. 2024 Jul 14;7:100262. doi: 10.1016/j.crmicr.2024.100262. eCollection 2024.
The paper industry faces two critical challenges: the scarcity of raw materials and the environmental impact of chemical waste pollution. Addressing the first challenge involves harnessing alternative, sustainable raw materials, while the second challenge can be mitigated through the adoption of bio-bleaching processes, which significantly reduce chemical consumption while enhancing paper brightness and quality. This study proposes a solution to both challenges by using non-woody Calotropis procera (Ankara) and a xylanase-producing microbial consortium for sustainable handmade paper production, a combination not extensively explored in prior research To evaluate this approach, the process was divided into three stages. In stage I, Ankara fibre was pulped through open hot digestion. In stage II, the pulp was subjected to bio-bleaching in two experimental setups: Set I (without sucrose) and Set II (with sucrose) for 5 days. In stage III, chemical bleaching was used to improve the final brightness of the treated pulps. A novel comparison was made between the bio-bleaching efficiency of an individual isolate g5 (BI) and a bacterial consortium (BC). This research highlighted that bio-bleaching with the consortium effectively removed lignin (140±60 mg/l) and colour (1830±50 PCU), especially in the presence of sucrose, compared to using a single xylanase isolate. Pulp residue/filtrate collected at each stage was estimated based on parameters such as colour and lignin content. After stage III (chemical bleaching), the release of colour and lignin in pulp filtrate was higher in BI compared to BC, indicating the consortium's effectiveness during bio-bleaching, which leaves fewer degradable lignin structures for the chemical bleaching stage. Papers crafted from consortium-treated pulp also exhibited higher brightness than those treated with the isolate. This study reveals the synergistic effect of microbial consortia, leading to more efficient lignin degradation and enhanced bio-bleaching capabilities, supporting the development of greener industrial processes. Ultimately, this study demonstrates a unique and eco-friendly approach to papermaking, combining C. procera and enzymatic bio-bleaching to reduce dependency on hazardous chemicals and support sustainable industry practices.
原材料短缺以及化学废物污染对环境的影响。应对第一个挑战需要利用替代性的可持续原材料，而第二个挑战可以通过采用生物漂白工艺来缓解，这种工艺能显著减少化学物质的消耗，同时提高纸张的亮度和质量。本研究提出了一种同时应对这两个挑战的解决方案，即使用非木质的牛角瓜（安卡拉）和一种产木聚糖酶的微生物群落来进行可持续手工纸生产，这种组合在以往研究中并未得到广泛探索。为了评估这种方法，该过程分为三个阶段。在第一阶段，通过开放式热蒸煮对牛角瓜纤维进行制浆。在第二阶段，将纸浆在两种实验设置下进行生物漂白：设置I（不加蔗糖）和设置II（加蔗糖），持续5天。在第三阶段，使用化学漂白来提高处理后纸浆的最终亮度。对单个菌株g5（BI）和细菌群落（BC）的生物漂白效率进行了新颖的比较。这项研究强调，与使用单一木聚糖酶菌株相比，群落生物漂白能有效去除木质素（140±60毫克/升）和颜色（1830±50 PCU），特别是在有蔗糖存在的情况下。根据颜色和木质素含量等参数对每个阶段收集的纸浆残渣/滤液进行了估算。在第三阶段（化学漂白）之后，与BC相比，BI处理的纸浆滤液中颜色和木质素的释放量更高，这表明群落在生物漂白过程中的有效性，使得化学漂白阶段可降解的木质素结构更少。用群落处理过的纸浆制成的纸张也比用菌株处理过的纸张具有更高的亮度。这项研究揭示了微生物群落的协同作用，导致更高效的木质素降解和增强的生物漂白能力，支持了更绿色工业流程的发展。最终，这项研究展示了一种独特且环保的造纸方法，将牛角瓜和酶促生物漂白相结合，以减少对有害化学物质的依赖，并支持可持续的工业实践。
