An optimal blend of single autodisplayed cellulases for cellulose saccharification – a proof of concept

Abstract

BACKGOUND To date, it has been challenging to determine the optimal proportions of the individual cellulases in crude extracts and multienzyme systems to promote enzyme synergism. The application of single surface‐display of enzymes may obviate such challenges. This article presents a proof of concept of the optimal mixing of single surface‐displayed cellulases for cellulose hydrolysis using Simplex lattice mixture design. RESULTS The recently discovered maximized autotransporter‐mediated expression system was used to express the three cellulases. The biochemical screening analysis revealed that the enzymes have a broad range of functional pH (4–9) and temperature (30–100 °C) characteristics. The evaluated optima were pH 6 and 60 °C. Through the statistical design of experiment, a blend ratio of 1: 1.6: 1.4 of endoglucanase: exoglucanase: β‐glucosidase was identified as the ‘sweet spot’ for optimum sugar yield. The application of this blend generated about 0.354 mg mL‐1 and 0.446 mg mL‐1 of sugars from filter paper (Ø 6 mm, ∼2.5 mg) and 2.5% pretreated EFB, respectively, within 12 h. Supplementing the enzyme blend with CaCl2 and Tween 20 improved the sugar yield. CONCLUSION This research has revealed an interesting concept of efficiently addressing cellulase synergism. The overall outcome of this research is promising for the derivation of value from lignocellulose. © 2018 Society of Chemical Industry

Sustainable Production of Bioethanol Using Levulinic Acid Pretreated Sawdust

“…In the current research, the simultaneous addition of cellulases (i.e., a blend of three cellulases) gave higher saccharification compared to the sequential addition of cellulases for 90 U of endoglucanase, 80 U of exoglucanase, and 220 U of -glucosidase. Obeng et al (2018) and Malgas et al (2020) also reported cellulase synergism for a cocktail of cellulases in enzymatic hydrolysis of biomass. However, the blend ratio and enzyme source were different, which might be responsible for the variation in results.…”

“…Therefore, the optimal amount of exoglucanase was required for a higher endoglucanase titer to prevent feedback inhibition. Similarly, a higher titer of glucosidase was required to prevent the feedback inhibition of endoglucanases and exoglucanases by cellobiose accumulation ( Obeng et al, 2018 ).…”

Improving saccharification of ramie stalks by synergistic effect of in-house cellulolytic enzymes consortium

“…and Aspergillus terreus , respectively (GarciaKirchner and Huitron 1996 ). It is reported that a blend ratio of 1:1.6:1.4 of endoglucanase: exoglucanase: β-glucosidase was identified as the sweet spot for optimum sugar yield (Obeng et al 2018 ). Similary, Fig.…”

Control cinético del salado, con sabor a humo, de filetes de tilapia (Oreochromis sp)

“…La Figura 3 muestra los resultados de la RSM, la combinación de factores estableció que transcurridos 161 minutos se logran los mejores resultados del proceso de salado, al alcanzar un valor de actividad de agua de 0,95 y un contenido de sal de 0,042 g NaCl/g en la fase líquida, que corresponde a un valor de de 0,17 g de NaCl/g en base seca al utilizar sal ahumada con envasado al vacío, Figura 4(A); en este tipo de salado se aporta el sabor característico a humo que está relacionado con una mayor aceptación sensorial (Obeng et al, 2018).…”