PEER-REVIEWED ARTICLE bioresources.com Parveen et al. (2022). “Bambusa balcooa treatments,” BioResources 17(4), 5578-5599. 5578 Comparative Study of Diverse Pretreatment Approaches to Degrade Lignin from Bambusa balcooa Heena Parveen, a, * Lakshmi Tewari, a Diwas Pradhan, b and Parul Chaudhary a Bamboo biomass is a potential source of monomeric sugars containing a high cellulose content with a low amount of lignin. However, for efficient hydrolysis, an effective biomass pretreatment technique is required to minimize the lignin content and other barrier components. In the present study, bamboo biomass was treated with different physical, chemical, biological, and combined treatments to reduce the lignin content. Among all the pretreatments, the maximum lignin removal amount (14.5%) was obtained with the combined chemical and biological treatment under 2% NaOH + 1% H2O2 + WDP2 fungal culture (5 plugs) conditions. In addition, the ligninolytic fungus and NaOH pretreatment was primarily effective in removing lignins, whereas the H2O2 pretreatment efficiently minimized cellulose crystallinity. Scanning electron microscopy and Fourier- transform infrared spectroscopy was utilized to analyze the structural changes of the raw and treated biomass. The structural analysis indicated that all the treatments caused disruption in the biomass structure and reduced the compactness of the biomass, which facilitated the biomass conversion during the hydrolysis process. The findings of the present study indicated effective pretreatment methods in overcoming the recalcitrancy of potential lignocellulosic biomass for maximum hydrolysis. DOI: 10.15376/biores.17.4.5578-5599 Keywords: Bambusa balcooa; Pretreatment; Ligninolytic fungus; SEM; FTIR Contact information: a: Department of Microbiology, Govind Ballabh Pant University of Agriculture & Technology, Pantnagar, Uttarakhand 263153 India; b: Department of Dairy Microbiology, National Dairy Research Institute, Karnal, Haryana 132001 India; *Corresponding author:heenahussain0000@gmail.com INTRODUCTION The increased worldwide energy demand has a noticeable effect on the economic sustainability and stability of the world (Moe et al. 2012). Many researchers in the biotechnology field have centered on the biological alteration of lignocellulosic biomass into simple sugars via the enzymatic hydrolysis of plant cell wall polyoses (Den et al. 2018). This can be applied to create a variety of downstream fuels and chemicals that meet global energy demands, as well as make an effort to decrease the reliance on conventional petroleum resources. Currently, most of the biorefinery approaches profoundly rely on either the biological alteration of lignocellulosic biomass or thermo-chemical progressions to produce transportation fuels (Foston and Ragauskas 2012). For the expansion of the plant based eco-friendly fuel industry, the chosen biomass resource should be present on a sustainable basis and also be affordable, with project sustainability as the concern. Bamboo has many special features, e.g., a very fast growth rate, short reconstruction, easy propagation, and is rich in cellulose and hemicellulose and low in lignin; as such, it promises to be a potential feedstock for bioethanol or other biofuels production (Kuttiraja et al. 2013). There are approximately 1,500 bamboo species in the world and more than 20