Understanding β‐mannanase from Streptomyces sp. CS147 and its potential application in lignocellulose based biorefining

Abstract

Hydrolytic enzymes such as cellulase and hemicellulase have been attracted in lignocellulose based biorefinery. Especially, mannanase has been a growing interest in industrial applications due to its importance in the bioconversion. In this study, an extracellular endo-β-1,4-D-mannanase was produced by Streptomyces sp. CS147 (Mn147) and purified 8.5-fold with a 43.4% yield using Sephadex G-50 column. The characterization of Mn147 was performed, and the results were as follows: molecular weight of ∼25 kDa with an optimum temperature of 50°C and pH of 11.0. The effect of metal ions and various reagents on Mn147 was strongly activated by Ca(+2) but inhibited by Mg(+2) , Fe(+2) , hydrogen peroxide, EDTA and EGTA. Km and Vmax values of Mn147 were 0.13 mg/mL and 294 μmol/min mg, respectively, when different concentrations (3.1 to 50 mg/mL) of locust bean gum galactomannan were used as substrate. In enzymatic hydrolysis of heterogeneous substrate (spent coffee grounds), Mn147 shows a similar conversion compared to commercial enzymes. In addition, lignocellulosic biomass can be hydrolyzed to oligosaccharides (reducing sugars), which can be further utilized for the production of biomaterials. These results showed that Mn147 is attractive in quest of potential bioindustrial applications.

Production of Novel Polygalacturonase from Bacillus paralicheniformis CBS32 and Application to Depolymerization of Ramie Fiber

“…The effects of various metal ions on PN32 activities are presented in Table 3. The results showed that the polygalacturonase activity of PN32 did not show a significant improvement by the addition of metal ions, unlike what has been previously reported [20,21,22,23,29,30,31]. PN32 activity with K + (105.3 ± 4.0%), Mg 2+ (105.2 ± 5.0%), Mn 2+ (103.6 ± 5.0%), Ni 2+ (102.4 ± 0.5%), and Zn 2+ (101.3 ± 0.9%) was similar to the control.…”

“…In the meantime, prepared samples mixture for control were incubated at 4 °C. The reducing sugars released by PN32 were measured by adding 100 μL of a 0.5% 3,5-dinitrosalicylic acid (DNS) solution, as described by Miller [21]. One unit (U) polygalacturonase activity was defined as the amount of enzyme that released 1 µmol of galacturonic acid per min under standard assay.…”

“…The relative activity of PN32 was measured by comparing it to a control group without metal ions (100%). The Michaelis constant (K m ), maximum reaction rate (V max ), and kinetic constant of purified PN32 were measured using the Lineweaver–Burk equation [23], Hanes–Woolf equation [21] and Eadie-Hofstee equation [22], with minor modifications. A constant enzyme concentration (0.01 mg) was incubated with different concentrations of pectin (0.625–10 mg/mL) under the standard assay conditions.…”

β-Mannanase Production Using Coffee Industry Waste for Application in Soluble Coffee Processing

“…The main enzymes involved in degradation of the mannan structures are β-mannanase, β-mannosidase, β-glycosidase, and α-galactosidase [7]. Mannanases can be produced by a wide range of microorganisms, including different fungi [8][9][10][11] and bacteria [12][13][14].…”

Enhanced In-Vitro Hemozoin Polymerization by Optimized Process using Histidine-Rich Protein II (HRPII)

“…Then, the column was loaded with a washing buffer (50 mM NaH 2 PO 4 , 300 mM NaCl, and 20 mM imidazole, and the pH was adjusted to 8.0 with NaOH) at 2 mL/min. Finally, the enzyme (HRP-II) was collected using an elution buffer (50 mM NaH 2 PO 4 , 300 mM NaCl, 10 mM imidazole, 0.005% Tween 20, and NaOH with a pH of 8.0 that was adjusted) at 2 mL/min [27,28,29,30].…”