International Journal of Biological Macromolecules 201 (2022) 298–307 Available online 7 January 2022 0141-8130/© 2022 Elsevier B.V. All rights reserved. Integrated pretreatment of banana agrowastes: Structural characterization and enhancement of enzymatic hydrolysis of cellulose obtained from banana peduncle Julie Baruah a, b , Pritam Bardhan a , Ashis K. Mukherjee a, c , Ramesh Chandra Deka b , Manabendra Mandal a , Eeshan Kalita a, d, * a Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, India b Department of Chemical Sciences, Tezpur University, Tezpur 784028, India c Institute of Advanced Study in Science and Technology, Vigyan Path Garchuk, Paschim Boragaon, Guwahati, Assam 781035, India d Department of Molecular Biology and Biotechnology, Cotton University, India A R T I C L E INFO Keywords: Cellulose Glucose production Optimization Modelling Banana peduncle ABSTRACT An integrated treatment coupling alkali, steam explosion and ammonia/chlorine-free bleaching with sequential mild acid pretreatment were performed to isolate and characterize cellulose from banana agrowastes followed by optimized enzymatic hydrolysis to glucose. The cellulose yield, compositional, microstructural, and morpho- logical analysis initially obtained from three post-harvest banana agrowastes (peel, pseudostem, and peduncle) were surveyed. Isolation parameters for banana peduncle agrowastes, the most efficient precursor, were reconfigured for acid hydrolysis by applying an orthogonal L 9 array of Taguchi design. Effects of solution-to-pulp ratio, acid concentration, temperature, and reaction time on physicochemical parameters were assessed resulting in ~81% cellulose recovery. Subsequently, cellulase driven enzymatic conversion to glucose was modelled using response surface methodology (RSM), where the mutual influences of incubation time, enzyme concentration, substrate concentration, and surfactant concentration were investigated. Artificial Neural Network (ANN) modelling further improved upon RSM optimizations ensuing ~ 97% optimized glucose yield, verified experimentally. 1. Introduction Conversion of underutilized agricultural biomass resources into value-added products, such as biofuels and platform chemicals, is a sustainable recourse for repurposing agricultural crop residues towards industrial valorisation. The main components of agricultural biomass residues are cellulose, hemicellulose and lignin, where cellulose and hemicellulose fractions are sugar polymers, making them a potential source of sugars viz., glucose and xylose [1]. Banana agrowastes despite being one of the most abundant lignocellulosic sources remains underutilized [2]. Bananas are widely cultivated in Asia, Latin America, and Africa with an annual production of over 116 million metric tonnes (MMT) globally and account for 16% of the total global food production. India is currently the highest producer with 27.9 MMT, followed by China, (10.1 MMT), and the Philippines (7.8 MMT) [3]. Consequently, the agrowastes generated thereof (banana peduncle, peels, leaves, and pseudostems) accumulate in enormous quantities, whereas it could serve as a viable lignocellulosic feedstock [4]. Glucose is a necessary sugar that serves as a platform component for producing chemicals, biofuels, and materials using chemical and bio- logical methods [5]. Glucose is traditionally derived from starch, how- ever, given the current food shortage globally, the quest for non-food sugar sources is significant and intriguing [6]. Cellulose, an alternate source for glucose production is an abundant polymer of β 1,4-glycosidic bond linked glucose units that can be hydrolysed either chemically or enzymatically. Enzymatic hydrolysis is preferred since it is gentle, extremely selective and prevents the formation of inhibitors for down- stream enzymatic conversions [7]. Given that celluloses in lignocellu- losic agrowaste are imperviously interwoven within matrices of hemicelluloses and lignin, enzymatic hydrolysis mandates pre- treatments for reorganising the inter-and intramolecular hydrogen bond network, the shape of cellulose, as well as lignin removal [8]. Some * Corresponding author at: Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, India. E-mail address: eeshankalita@gmail.com (E. Kalita). Contents lists available at ScienceDirect International Journal of Biological Macromolecules journal homepage: www.elsevier.com/locate/ijbiomac https://doi.org/10.1016/j.ijbiomac.2021.12.179 Received 27 October 2021; Received in revised form 27 December 2021; Accepted 28 December 2021