Nutritional, therapeutic, and industrial valorization of corn silk, cob, and husk: a review

Corn processing industries generate a wide range of residues having significant potential for various applications and offer multiple health benefits. Corn residues, comprising by-products such as corn silk, cob, and husk, represent an abundant and underutilized resource with significant nutritional, therapeutic, and industrial potential. Corn silk is a significant source of phytochemicals and has been investigated for its therapeutic applications, including diuretic, antihyperglycemic, and hepatoprotective properties. Corn cobs, often undervalued, are abundant in cellulose, hemicellulose, and lignin, making them useful for producing bio-composites, biodegradable films, and adsorbents for environmental remediation. Corn husks are primarily composed of lignocellulosic material and bioactive compounds, making them valuable for developing biodegradable packaging, cellulose-based films, and adsorbents. Moreover, the phenolic acids found in corn husks are composed of ferulic acid. Ferulic acid has potent antioxidant properties, helping to regulate cellular oxidation and protect biological macromolecules like DNA and proteins from oxidative damage. Innovations in processing techniques have enhanced the use of corn residues in diverse sectors, such as the food and non-food sectors. This review comprises an overview of residues produced by the corn processing industries and their nutritional composition, highlighting their richness in dietary fibers, carbohydrates, protein, bioactive compounds, and essential minerals. It also emphasizes the therapeutic potential and diverse food and non-food applications of corn residues. This review underscores the need for continued research and industrial-scale adaptation to maximize the utility of corn residues, thereby promoting sustainability and bioeconomy practices in agro-industrial systems.