Improvement in Enzyme Activity and Stability by Addition of Low Molecular Weight Polyethylene Glycol to Sodium bis(2-ethyl-L-hexyl)sulfosuccinate/ Isooctane Reverse Micellar System

Talukder, Md. Mahabubur Rahman; Takeyama, Tomokiyo; Hayashi, Yoshinori; Wu, Jin; Kawanishi, Takuya; Shimizu, Nobuaki; Ogino, Chiaki

doi:10.1385/abab:110:2:101

Cited by 21 publications

(8 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Examples of this beneficial effect have been reported for enzymes such as horseradish peroxidase (HRP) [22], lipoxygenase (LOX1) [23], lipase [24,25], xylanase [22], β-glucosidase and cellualse [1,[26][27][28][29]. Various mechanisms of action have been described to explain these effects that will be described further in this manuscript.…”

Section: Introductionmentioning

confidence: 99%

A Review of the Role of Amphiphiles in Biomass to Ethanol Conversion

2013

View full text Add to dashboard Cite

Abstract:One of the concerns for economical production of ethanol from biomass is the large volume and high cost of the cellulolytic enzymes used to convert biomass into fermentable sugars. The presence of acetyl groups in hemicellulose and lignin in plant cell walls reduces accessibility of biomass to the enzymes and makes conversion a slow process. In addition to low enzyme accessibility, a rapid deactivation of cellulases during biomass hydrolysis can be another factor contributing to the low sugar recovery. As of now, the economical reduction in lignin content of the biomass is considered a bottleneck, and raises issues for several reasons. The presence of lignin in biomass reduces the swelling of cellulose fibrils and accessibility of enzyme to carbohydrate polymers. It also causes an irreversible adsorption of the cellulolytic enzymes that prevents effective enzyme activity and recycling. Amphiphiles, such as surfactants and proteins have been found to improve enzyme activity by several mechanisms of action that are not yet fully understood. Reduction in irreversible adsorption of enzyme to non-specific sites, reduction in viscosity of liquid and surface tension and consequently reduced contact of enzyme with air-liquid interface, and modifications in biomass chemical structure are some of the benefits derived from surface active molecules. Application of some of these amphiphiles could potentially reduce the capital and operating costs of bioethanol production by reducing fermentation time and the amount of enzyme used for saccharification of biomass. In this review article, the benefit of applying amphiphiles at various stages of ethanol production (i.e., OPEN ACCESSAppl. Sci. 2013, 3 397 pretreatment, hydrolysis and hydrolysis-fermentation) is reviewed and the proposed mechanisms of actions are described.

show abstract

Section: Introductionmentioning

confidence: 99%

A Review of the Role of Amphiphiles in Biomass to Ethanol Conversion

2013

View full text Add to dashboard Cite

show abstract

“…In order to enhance the activity of lipases entrapped in AOT reverse micelles, several methods have been reported: use of chemically modified AOT,6 and introducing nonionic surfactant such as Tween 85 or small molecular weight polyethylene glycols as additives 7–9. The preparation of chemically‐modified AOT is very complicated and the activity enhancement is also limited.…”

Section: Introductionmentioning

confidence: 99%

Pretreatment of Chromobacterium viscosum lipase with acetone increases its activity in sodium bis‐(2‐ethylhexyl) sulfosuccinate (AOT) reverse micelles

Talukder

Zaman

Hayashi

et al. 2005

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

The activity of Chromobacterium viscosum lipase for hydrolysis of olive oil in sodium bis-(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles was increased by pretreatment with acetone. In contrast to the untreated lipase, no sharp fall in the activity of the treated lipase at higher W 0 (water to AOT molar ratio) values was observed. The fluorescence emission intensity of the treated lipase in reverse micelles was higher than that of the untreated lipase but the maximal emission wavelength (λ max ) was the same for both lipases. A kinetic model that considers the free substrate in equilibrium with the substrate adsorbed on the micellar surface was successfully used to better understand the activity enhancement. The Michaelis constant (K m ) and substrate adsorption equilibrium constant (K ad ) were reduced by lipase pretreatment with acetone whereas the maximum reaction rate (v max ) remained unaltered.

show abstract

“…When the fraction of activated lipase was estimated by eqn (5), it increased with the increase in PEG 400 concentration (data not shown), and the ratio (x a /x n ) reached 3.2 at optimum PEG 400 concentrations. It should be noted that the optimum concentration of PEG 400 in the AOT reverse micellar system was found to be 0.015 mol dm −3 , above which the addition of PEG 400 makes the reverse micellar solution turbid, 15 and the lipase activity decreases.…”

Section: Resultsmentioning

confidence: 99%

Enzymatic kinetics for lipase‐catalyzed hydrolysis of water‐insoluble substrate in AOT reverse micelles, involving native and activated lipases

Talukder

Zaman

Hayashi

et al. 2004

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

The addition of short chain polyethylene glycols (PEGs) activated Chromobacterium viscosum lipase in AOT reverse micelles. In this study, it was assumed that when AOT reverse micelles contained PEG molecules, native and activated lipases contributed to the reaction according to their weight fraction in the system. The fractions of individual lipases and their specific activities were estimated by using kinetics parameters determined by previous kinetic models. The maximum specific activity of PEGactivated lipase appeared to be 2.7 times higher than that of native lipase. The predicted weighted-average activity agreed well with experimental data. The results showed that the previous kinetic models could be used to estimate the fraction of lipase activated by PEG molecules and their specific activity.

show abstract

Improvement in Enzyme Activity and Stability by Addition of Low Molecular Weight Polyethylene Glycol to Sodium bis(2-ethyl-L-hexyl)sulfosuccinate/ Isooctane Reverse Micellar System

Cited by 21 publications

References 37 publications

A Review of the Role of Amphiphiles in Biomass to Ethanol Conversion

A Review of the Role of Amphiphiles in Biomass to Ethanol Conversion

Pretreatment of Chromobacterium viscosum lipase with acetone increases its activity in sodium bis‐(2‐ethylhexyl) sulfosuccinate (AOT) reverse micelles

Enzymatic kinetics for lipase‐catalyzed hydrolysis of water‐insoluble substrate in AOT reverse micelles, involving native and activated lipases

Contact Info

Product

Resources

About