Valorization of corn waste for hemicellulose extraction and xylitol production: Comparative study of different extraction methods

Abstract Corn waste, specifically corn cobs (23%) and corn sheaths (16%), is a significant byproduct of corn processing that is often underutilized and typically discarded as agricultural residue. However, these waste streams are rich in hemicellulose, which can be extracted and used for various applications. To isolate hemicellulose, the efficacy of several methods of extraction was measured in terms of yield. The conventional method uses traditional heating, while microwave and ultrasound methods leverage advanced energy sources to speed up the extraction process. The influence of process parameters, such as temperature, time and NaOH concentration, on hemicellulose yield and degree of polymerization was assessed by response surface methodology. The optimized conditions for ultrasound extraction were found to be a 10.00% NaOH concentration, a duration of 35.00 min and a temperature of 45 °C, resulting in a hemicellulose yield of 82.28%. The isolated hemicellulose was further fermented using Candida tropicalis (MTCC 230) for xylitol production, with this strain achieving a maximum xylitol yield of 16.54 g/L. This study highlights the potential for converting agricultural waste into value‐added products, addressing both waste management challenges and the need for renewable, environmentally friendly industrial processes.