Value addition of corn husks through enzymatic production of xylooligosaccharides

Abstract

Corn husks are the major wastes of corn industries with meagre economic significance. The present study was planned for value addition of corn husk through extraction of xylan, followed by its enzymatic hydrolysis into xylooligosaccharides, a pentose based prebiotic. Compositional analysis of corn husks revealed neutral detergent fibre 68.87%, acid detergent fibre 31.48%, hemicelluloses 37.39%, cellulose 29.07% and crude protein 2.68%. Irrespective of the extraction conditions, sodium hydroxide was found to be more effective in maximizing the yield of xylan from corn husks than potassium hydroxide (84% vs. 66%). Application of xylanase over the xylan of corn husks resulted into production of xylooligosaccharides with different degree of polymerization namely, xylobiose and xylotriose in addition to xylose monomer. On the basis of response surface model analysis, the maximum yield of xylobiose (1.9 mg/ml) was achieved with the enzymatic hydrolysis conditions of pH 5.8, temperature 44°C, enzyme dose 5.7U/ml and hydrolysis time of 17.5h. Therefore, the corn husks could be used as raw material for xylan extraction vis a vis its translation into prebiotic xylooligosaccharides.

Optimization of alkaline pretreatment and enzymatic hydrolysis for the extraction of xylooligosaccharide from rice husk

“…Incubation time is one of the factors that directly influenced by XOS production yield. Similar to this study, the increasing incubation time showed the raised of XOS production yield (Samanta et al 2014 , 2016 ). The effect of substrate concentration for XOS production was carried out by different concentration of xylan.…”

“…From the previous reports, enzyme dose was varied from 2 to 200 U from XOS production presented in previous studies (Brienzo et al 2010 ; Chapla et al 2012 ; Gowdhaman and Ponnusami 2015 ; Jayapal et al 2013 ; Samanta et al 2014 ; Siti-Normah et al 2012 ). The increasing of enzyme concentration from 2.65 to 13.25 U were significantly increased the reducing sugars after enzyme hydrolysis (Samanta et al 2014 , 2016 ). In the present study, the decreasing enzyme concentration exhibited the decreased XOS yield.…”

Preparation and nutritional properties of xylooligosaccharide from agricultural and forestry byproducts: A comprehensive review

“…A similar xylan yield can be obtained when xylan is extracted from dry corncob with 10% sodium hydroxide at 75°C ( 89 ). The yields of XOS were 83 and 84.5%, respectively, when xylan were extracted from corncob and corn shells with 12% sodium hydroxide solution with the steam pre-treatment ( 6 , 92 ). Ultrasonic assisted alkali extraction can significantly improve the yield of XOS in corncob, and the content of related XOS can reach 174.81 mg/g matrix ( 93 ).…”

Green production of prebiotic xylooligosaccharides via enzymatic hydrolysis from xylan black liquor of oil palm frond

“…Through the breaking of the glycosidic linkages of xylose, hemicellulose is segregated into oligosaccharides of a broad DP range in addition to monosaccharides in this method (de Freitas et al 2019;Poletto et al 2020). As reported by Samanta et al (2016), xylan extracted from corn husk was converted at a 44 C for 17.5 h of enzymatic hydrolysis to produce a maximum xylobiose concentration of 1.9 mg/mL. Enzymatic hydrolysis does not produce unwanted byproducts or a large amount of monosaccharides.…”