Recombinant Fungal Enzymes for Lignocellulosic Biomass Hydrolysis for Biofuel Application

Agricultural residues in the form of rice straw, wheat straw, sugarcane bagasse and trash, cotton stock, etc., are the most abundant carbohydrate sources on earth. These residues, which are also known as lignocellulosic biomass, are mostly composed of lignin (a phenolic polymer), cellulose and hemicellulose (sugar polymers). Sugar polymers often account for up to 70% of the biomass and, if depolymerized into monomeric sugars, they could serve as abundant, cheap carbon sources for fermenting into biofuels, such as bioethanol or any other industrially-relevant products. However, cellulose and hemicellulose, being structural polymers, are difficult to hydrolyze into monomeric sugars, and the enzymes available are inefficient and expensive.
Via an extensive bioprospecting study, we identified a fungal isolate that efficiently degrades lignocellulosic biomass that has been pretreated to loosen or remove the lignin. The genomics, transcriptomic and proteomic profiles of the fungal isolate were analysed to understand the nature of the cellulolytic enzymes secreted and their regulation. The fungus was further genetically engineered to derepress the enzyme secretion and overexpress key enzymes, which led to 8-9 -fold increase in titer and enhanced biomass hydrolyzing efficiency. The techno-economic analysis also indicated the cost-effectiveness of the process.

There is no enzyme available in the market for lignocellulose hydrolysis. although, Novozymes has made its enzyme available to selected customers who would be potential manufacturers of second-generation ethanol. From rigorous comparative testing with our partners, we have determined the following properties of our enzymes:
• Quality – The enzyme composition is enriched in high quality cellulase and xylanase enzymes, that work at very doses to efficiently hydrolyze the tested biomasses
• Enhanced efficacy – The enzyme composition can 15% enhanced efficacy in terms of monomeric sugar titer over the marketed product
• Cost advantage – The technology package includes a significant cost-advantage over the existing product.
• Shelf life – The enzyme preparation is stable for more than a year at 4°C.
• Ease of use – The downstream processing is negligible, and the product is very easy to use in terms of its operating parameters.

Quality – The enzyme composition is enriched in high quality cellulase as well as xylanase enzymes, that works at very dose to hydrolyze the biomass
Enhanced efficacy – The enzyme composition can offer10-15% enhanced efficacy in terms of monomeric sugar titer over the marketed product
Cost advantage – The technology package includes cost-advantage over the existing product.
Shelf life – The enzyme preparation is stable for more than a year at 4 oC.
Ease of use – The downstream processing is negligible, and the product is very easy to use in terms of its operating parameters.

The major application of the technology is for producing the second-generation biofuel. This technology can also be used by any biomass processing company that wants to hydrolyze the biomass into monomeric sugars and ferment them into useful industrial products. Another use of cellulase enzyme technology is in animal feed to increase the availability of digestible sugars.

The raw materials required for producing enzymes are readily available in the market in bulk, and the list can be made available on request.

Indian Patent Application No. 202211043651 -Optimized gene editing in fungal cells and recombinant endonuclease therefor
PCT/IB2021/052791-Enzyme Overexpression for Optimized Lignocellulosic Degradation
US20190032037A1-A method for obtaining a composition for biomass hydrolysis
202011014805-Enzyme Overexpression for Optimized Lignocellulosic Degradation
201711019184-Fungal Strain With Impaired Catabolite Repression
for Lignocellulosic Degradation
1714/DEL/2015-A method for obtaining a composition for biomass hydrolysis
WO2017006352A3
US20190032037A1-A method for obtaining a composition for biomass hydrolysis
201711019184-Fungal Strain with Impaired Catabolite
Repression for Lignocellulosic Degradation