Optimization of mannooligosaccharides production from different hydrocolloids via response surface methodology using a recombinant Aspergillus sojae β‐mannanase produced in the microparticle‐enhanced large‐scale stirred tank bioreactor

In this study, a recombinant Aspergillus sojae beta (β)-mannanase produced from carob extract in the microparticle-enhanced bioreactor was applied to locust bean gum (LBG) and guar gum (GG) as hydrocolloids. The effects of enzyme amount (EA), temperature (T), and gum concentration (GC) on mannooligosaccharides (MOSs) enzymatic fabrication were examined using Box–Behnken response surface methodology. Under optimized conditions (GC = 1%, T = 40°C, EA = 7.5 ml, and incubation time = 10 min for LBG and GC = 0.75%, T = 50°C, EA = 7.5 ml, and incubation time = 35 min for GG), the M2, M3, M4, M5, and M6 fabrications from LBG were 455.2, 801.1, 101.1, 346.9, and 1,592.3 ppm, while the M2, M3, and M6 concentrations from GG were 92.85, 220.99, and 1,882.54 ppm, respectively. The M6 was the most dominant MOS from both gums. Consequently, LBG and GG can be potential sources of MOS production. It has been observed that MOS productions can be enhanced by optimizing β-mannanase enzyme treatment conditions. Practical applications In recent years, MOS has gained attention due to its prebiotic efficacy that prevents infections by regulating the intestinal microbiota and reducing the risk of various chronic degenerative diseases. β-mannanases are extracellular enzymes that hydrolyze 1,4-β-D mannosidic bonds in mannan, galactomannan, glucomannan, and galactoglucomannans. Locust bean gum (LBG) and guar gum (GG) can be used in the production of mannooligosaccharides (MOS) which is well known to have prebiotic effects. Both hydrocolloid substances are rich in point of mannans, galactomannans, glucomannans, and galactoglucomannans. Therefore, these compounds can be hydrolyzed to produce MOS from different hydrocolloids using β-mannanases. In this study, to produce MOS from gums, β-mannanase obtained from Aspergillus sojae fermentation was used. The results showed that LBG and GG could be a potential source of MOS production. It has been observed that higher amounts of MOS production can be achieved by optimizing β-mannanase enzyme treatment conditions.