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and the presence of ferulic acid having some antioxidant properties (Katapodis et al.
2003). The degree of branching and spatial arrangement of arabinoxylans recovered
by different methods can influence nutraceutical potential (Saulnier et al. 2007).
Also, the structural characteristics and molecular weight of arabinoxylans can affect
the techno-functional properties of the products (Sun et al. 2011). So in order to
acquire the improved functional, technological and nutraceutical properties, various
physical, chemical, and enzymatic methods have been used to modify arabinoxylan
molecule.
Physical Modification
Physical modification of arabinoxylans includes ultrasonic and microwave assisted
modification. Arabinoxylans subjected to ultrasonic power (120–480 W) and treat
time (15–45 min) resulted in increased phenolic compounds and antioxidant properties whereas the chemical composition remained unchanged upon the treatment.
The molecular weight, main chain composition and monosaccharide constituents of
arabinoxylans significantly decreased after ultrasound treatment. Upon ultrasonication arabinoxylans resulted in low viscosity gels (Li et al. 2016). Microwave irradiation is the another method for modification, when applied in the temperature-time
range of 160–200 °C for 2–20 min results in production of arabinoxylans with a
wide range of molecular weights and some of them being highly feruloylated. These
feruloylated arabinoxylans may confer health benefits by preventing oxidation
stress and having prebiotic effects (Rose and Inglett 2010).
Chemical Modification
The chemical modifications include carboxymethylation, arabinoxylan Na salt formation, and esterification. Carboxymethylation of arabinoxylan with sodium monochloroacetate resulted in replacement of –OH group with carboxymethyl group.
Carboxymethylation of arabinoxylan yielded water soluble derivative with antimicrobial activity. The carboxymethylation of arabinoxylan represents a useful way to
get water soluble arabinoxylan derivatives with anionic functions (Erum et al.
2015). Bhatia and Ahuja (2015) reported that carboxymethylation of arabinoxylan
from psyllium resulted in increased crystallinity, decreased viscosity and improved
thermal stability. In arabinoxylan-Na salt formation, antimicrobial activity was
observed to be concentration dependent with partial solubility in water (Erum et al.
2015). In esterification, arabinoxylans are treated with a C2–C4 aliphatic anhydride
using methanesulfonic acid as a catalyst or trifluoroacetic anhydride as a promoter.
The resulted arabinoxylan esters are amorphous with high molecular weight, soluble in a range of solvents and thermally stable upto 200 °C (Buchanan et al. 2003).
Arabinoxylans
and the presence of ferulic acid having some antioxidant properties (Katapodis et al.
2003). The degree of branching and spatial arrangement of arabinoxylans recovered
by different methods can influence nutraceutical potential (Saulnier et al. 2007).
Also, the structural characteristics and molecular weight of arabinoxylans can affect
the techno-functional properties of the products (Sun et al. 2011). So in order to
acquire the improved functional, technological and nutraceutical properties, various
physical, chemical, and enzymatic methods have been used to modify arabinoxylan
molecule.
Physical Modification
Physical modification of arabinoxylans includes ultrasonic and microwave assisted
modification. Arabinoxylans subjected to ultrasonic power (120–480 W) and treat
time (15–45 min) resulted in increased phenolic compounds and antioxidant properties whereas the chemical composition remained unchanged upon the treatment.
The molecular weight, main chain composition and monosaccharide constituents of
arabinoxylans significantly decreased after ultrasound treatment. Upon ultrasonication arabinoxylans resulted in low viscosity gels (Li et al. 2016). Microwave irradiation is the another method for modification, when applied in the temperature-time
range of 160–200 °C for 2–20 min results in production of arabinoxylans with a
wide range of molecular weights and some of them being highly feruloylated. These
feruloylated arabinoxylans may confer health benefits by preventing oxidation
stress and having prebiotic effects (Rose and Inglett 2010).
Chemical Modification
The chemical modifications include carboxymethylation, arabinoxylan Na salt formation, and esterification. Carboxymethylation of arabinoxylan with sodium monochloroacetate resulted in replacement of –OH group with carboxymethyl group.
Carboxymethylation of arabinoxylan yielded water soluble derivative with antimicrobial activity. The carboxymethylation of arabinoxylan represents a useful way to
get water soluble arabinoxylan derivatives with anionic functions (Erum et al.
2015). Bhatia and Ahuja (2015) reported that carboxymethylation of arabinoxylan
from psyllium resulted in increased crystallinity, decreased viscosity and improved
thermal stability. In arabinoxylan-Na salt formation, antimicrobial activity was
observed to be concentration dependent with partial solubility in water (Erum et al.
2015). In esterification, arabinoxylans are treated with a C2–C4 aliphatic anhydride
using methanesulfonic acid as a catalyst or trifluoroacetic anhydride as a promoter.
The resulted arabinoxylan esters are amorphous with high molecular weight, soluble in a range of solvents and thermally stable upto 200 °C (Buchanan et al. 2003).
Arabinoxylans