Browsing by Author "Rajeev Kumar Kapoor"

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Bioresources, environmental aspects, and patent scenario for biobleaching in pulp and paper industry
(Elsevier, 2023) Guddu Kumar Gupta; Gaurav Pathak; Pratyoosh Shukla; Rajeev Kumar Kapoor
The traditional paper pulp bleaching method involves the use of harsh chemicals; consequently vast amounts of hazardous substances in the form of bleach outflows are discharged into water bodies. These outflows mostly contaminate and disturb air quality, aquatic life, and food chain. To stop the adverse effect of these contaminants strict monitoring of the industrial effluent and implementation of environmental regulatory laws should be ensured. Further, strict legal action should be taken against the defaulters. The scientific community should suggest new ecofriendly methods for biobleaching. This chapter summarizes the significant efforts that academic institutions and enterprises have made to replace chemical bleaching agents with microbially produced enzymes. Paper mills should now start using the enzymatic bleaching technique (biobleaching) instead of a typical chemical bleaching approach. Key enzymes applicable to biobleaching strategies are hemicellulases, cellulases, amylases, lipases, laccases, ligninases, and xylanases. These enzymes, however, can be used singly or in conjunction with other enzymes. Generally, their cocktail comprising mainly xylanases, and laccases along with certain mediators, are used in the biobleaching processes. This chapter analyzes the potential usage of enzymes in biobleaching and deinking of mixed pulp in paper mills. © 2023 Elsevier Inc. All rights reserved.
Improved deinking and biobleaching efficiency of enzyme consortium from Thermomyces lanuginosus VAPS25 using genetic Algorithm-Artificial neural network based tools
(Elsevier Ltd, 2022) Mandeep Dixit; Guddu Kumar Gupta; Monika Yadav; Deepak Chhabra; Rajeev Kumar Kapoor; Puneet Pathak; Nishi K. Bhardwaj; Pratyoosh Shukla
The present study reports the combined enzymatic production efficiency of thermophilic fungus Thermomyces lanuginosus VAPS25 using a combinatory artificial intelligence-based tool, resulting in 2.7 IU/ml, 5.2 IU/ml, and 18.85 U/ml activity of endoglucanase, amylase, and lipase, respectively with good thermostability at 90 °C (pH 8–10). Interestingly, the metal ions viz. Cu2+ and Mg2+ increased the endoglucanase activity to 5 folds, i.e.,5.6 IU/ml compared to control. Further, the amylase and lipase activity was also enhanced by Fe2+ and Co2+ to 5.4 IU/ml and 19.57 U/ml, respectively. Additionally, the deinking efficiency was improved by 68.9%, 42.7%, and 52.8% by endoglucanase, amylase, and lipase, respectively, while the consortium increased the deinking efficiency to 72.7%. The bio-bleached paper strength parameters such as burst index, breaking length, tear index, and tensile index of sheets were significantly improved by 1.38%, 13.54%, 7.54%, and 20.88%, respectively. These enzymes at an industrial scale would help develop an economical paper recycling process. © 2022 Elsevier Ltd
Improved GA-ANN based optimized bio-deinking strategy for laccase produced from Trametes versicolor GGRK18, and its gene co-expression network analysis
(Elsevier Ltd, 2025) Guddu Kumar Gupta; Tallon Coxe; Eetika Chot; Rajeev Kumar Kapoor; Deepak Chhabra; Nishi K. Bhardwaj; Rajeev Kumar Azad; Pratyoosh Shukla
Recycling of waste paper through chemical deinking process led the generation of toxic agents and caused severe issues. Therefore, an alternative deinking process of recycled waste paper is necessity to sustain the eco-friendly environment. This study reports the production of laccase from Trametes versicolor GGRK18 using a genetic algorithm-artificial neural network (GA-ANN) tool, resulting in increased 21.5-fold i.e., 42.06 ± 1.1–906.17 ± 46.76 U/mL laccase activity. The biochemical studies revealed that laccase showed optimum activity at 60 ℃ and pH 4.0, retaining more than 90 % residual activity . Interestingly, the metal ion K+ influenced the laccase activity by 4830.91 ± 129.3 U/mL, and obtained laccase showed an apparent K m value of 0.5 µM and V max of 1666.67 µmol/mL/min. Furthermore, the deinking efficiency was improved by 48 % and 29.3 % for photocopier and newspaper, while the brightness increased by 34.6 % and 10.4 %, respectively, compared to the control values. The tearing index was significantly improved with 18.2 % and burst factor efficiently decreased by 21.1 % of deinked pulp. Furthermore, our study employs Weighted Correlation Network Analysis (WGCNA)-an R package designed to elucidate gene interactions– using next-generation sequencing data. The resulting network revealed over 70000 interactions among approximately 8917 unique genes, which clustered into 11 distinct modules of co-expressed genes; importantly, laccase genes exhibited co-expression patterns associated with various metabolic processes and oxidative stress pathways. In addition, this study also gives a combinatory strategy for waste paper recycling using laccase-mediated paper deinking and its mechanistic understanding of co-expressed genes in T. versicolor. © 2025 Elsevier Ltd.
Microbial enzyme bioprocesses in biobleaching of pulp and paper: technological updates
(Elsevier, 2023) Guddu Kumar Gupta; Mandeep Dixit; Dharini Pandey; Rajeev Kumar Kapoor; Naveen Kango; Pratyoosh Shukla
Lignocellulosic biomass has become a centre of atention due to its availability as a rapidly renewable source for utilization in the industrial sector. Being an economical substrate it has numerous avenues for its utlization as a substrate for the generation of biofuel and utlization in pulp and paper industry. Various fungi and bacteria can degrade lignocellulosic biomass by their degrading enzymes. Due to the high efficiency and stable metabolic capability, currently, the fungal enzymes have a broad range of industrial applications. Moreover, lignocellulosic biomass is cost-effective, environmentally friendly, and nonhazardous and requires lower energy input. The microbial enzymes have been used for the biobleaching of pulp and this approach is reported as cost-effective and ecofriendly compared to the conventional beaching process. It may improve the economic feasibility of the approach by lowering material costs and enhancing the pulp properties. Various enzyme engineering technologies enhance catalytic activity and substrate selectivity. This chapter will be discussing the technological updates on different microbial enzyme bioprocess techniques in the biobleaching of pulp and paper industries. © 2023 Elsevier Inc. All rights reserved.
Synergistic effect of cellulo-xylanolytic and laccase enzyme consortia for improved deinking of waste papers
(Elsevier Ltd, 2024) Guddu Kumar Gupta; Rajeev Kumar Kapoor; Deepak Chhabra; Nishi Kant Bhardwaj; Pratyoosh Shukla
This study reports the cellulo-xylanolytic cocktail production from Hypocrea lixii GGRK4 using multi-objective genetic algorithm-artificial neural network tool, resulting in 8.32 ± 1.07 IU/mL, 51.53 ± 3.78 IU/mL activity of CMCase and xylanase, respectively with more than 85 % residual activity at 60 °C and pH 6.0. Interestingly, metal ions viz. K+ and Ca2+ stimulated the enzyme activity, whereas Fe2+ and Cu2+ reduced the activity. Significant amounts of hydrophobic compounds, chromophores, and phenolics were released after wastepapers deinking. The deinking efficiency of 73.60 ± 2.45 % and 38.60 ± 1.34 % was obtained for photocopier paper and newspaper, respectively, whereas brightness of 89.90 ± 2.10 % ISO and 44.90 ± 1.63 % ISO was reported for both types of waste papers. The physical strength of deinked photocopier paper and newspapers, i.e., tensile index (3.10 and 0.50 %), tearing index (7.10 and 4.83 %), and burst factor (8.61) were enhanced whereas double fold property was decreased proving wastepaper reusability. This consortium showed effective and significant enzymatic deinking efficiency for recycled wastepapers. © 2024 Elsevier Ltd
Xylanolytic Enzymes in Pulp and Paper Industry: New Technologies and Perspectives
(Humana Press Inc., 2022) Guddu Kumar Gupta; Mandeep Dixit; Rajeev Kumar Kapoor; Pratyoosh Shukla
The pulp and paper industry discharges massive amount of wastewater containing hazardous organochlorine compounds released during different processing stages. Therefore, some cost-effective and nonpolluting practices such as enzymatic treatments are required for the potential mitigation of effluents released in the environment. Various xylanolytic enzymes such as xylanases, laccases, cellulases and hemicellulases are used to hydrolyse raw materials in the paper manufacturing industry. These enzymes are used either individually or in combination, which has the efficient potential to be considered for bio-deinking and bio-bleaching components. They are highly dynamic, renewable, and high in specificity for enhancing paper quality. The xylanase act on the xylan and cellulases act on the cellulose fibers, and thus increase the bleaching efficacy of paper. Similarly, hemicellulase enzyme like endo-xylanases, arabinofuranosidase and β-d-xylosidases have been described as functional properties towards the biodegradation of biomass. In contrast, laccase enzymes act as multi-copper oxidoreductases, bleaching the paper by the oxidation and reduction process. Laccases possess low redox potential compared to other enzymes, which need some redox mediators to catalyze. The enzymatic process can be affected by various factors such as pH, temperature, metal ions, incubation periods, etc. These factors can either increase or decrease the efficiency of the enzymes. This review draws attention to the xylanolytic enzyme-based advanced technologies for pulp bleaching in the paper industry. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.