Performance of β-glucosidase immobilized on calcium alginate beads

Performance of immobilized β-glucosidase obtained from almonds (EC 3.2.1.21) on calcium alginate beads was studied by measuring the activity of the enzyme in terms of the generation of pnitrophenol from the hydrolysis of p-nitrophenyl-β-D-glucopyranoside (PNPG).The immobilized enzyme activity was compared with soluble enzyme and was found to decrease by 36.6% albeit with an increased operational stability in terms of easy recovery from the finished product, recurrent use and scale-up in various reactor configurations. The hydrolysis rate data exhibit Michaelis-Menten kinetics. The Michaelis constant were determined using Langmuir linearized plot which obtained vmax and Km as 20.88 μmol/mL.min and 0.0125 mol/L respectively. However, the immobilized β-Glucosidase did not show a sufficiently good operational stability on reuse. Keywords: Immobilized enzyme, enzyme activity, Michaelis-Menten kinetics, β-glucosidase, pnitrophenyl- β-D-glucopyranoside (PNPG), alginate ge

Study of intraparticle diffusionreaction of substrate for Michaelis–Menten kinetics in a porous slab catalyst

The effect of internal diffusion on the overall reaction rate in a biocatalyst having slab geometry containing an immobilized enzyme or cells have been investigated theoretically. Zero-order, first-order and Michaelis-Menten kinetics were studied. The exact solutions for zero-order and first- order reactions were studied to verify our numerical algorithm which was later used to obtain solution for the Michaelis-Menten kinetic. The concentration profiles within the catalyst slab were obtained as a function of Thiele modulus which in turn were used to evaluate effectiveness factor. The exact solutions for zero and first order reactions can be obtained analytically. However one has to resort to numerical solution for Michaelis Menten kinetics as the resulting nonlinear differential equation cannot be solved analytically for the exact solution. Thus, for the Michaelis–Menten kinetics, the diffusion-reaction equation is solved using numerical method employing an explicit finite difference scheme which proved to be stable and accurate. A simple third order polynomial solution to the differential equation is also proposed. The approximate solution shows close agreement (error about less than 10%) with the numerical solution within the range of parameters of practical significance such as Thiele modulus values up to 8. Thus the approximate solution obtained in this work gives quite satisfactory results for a wide range of Thiele modulus compared to that reported in the literature. The nutrients diffuse deeper into the pellet with decreasing Thiele moduli for the three rate kinetics studied. The effectiveness factor decreases with increasing Thiele moduli which is in agreement with the trend in concentration profile for all the cases investigated and the range of parameters studied. Keywords: Diffusion-reaction; Michaelis–Menten kinetics; Immobilized slab biocatalyst; Finite difference method; Approximate solutio

Procedural Management Based Marketing Strategies for Lays Chips Company in Pakistan

This paper mainly focuses on the marketing strategy of lays company in Pakistan. Lays is a potato chips manufacturing company operating all over the world with huge marketing setup in Pakistan. To define a business model, it must be a set of strategies and plans, which any business adapt to making the market share and the market place. A business should choose the strategies which define itself different from the competitors. In this study, we will discuss lays chips digitalization that how this chips company is offering its services digitally through social media platforms in Pakistan. Value proposition also involved primarily in the lays company in the shape of chips packaging, discounts, more wide range of customer attractive strategies and tours in a very comfortable way. This research also focuses giving best ever potato chips in Asian regions.&nbsp

Diffusion-reaction of substrate in cylindrical immobilized bio-catalyst

The mass transfer effect on the overall reaction rate in a cylindrical immobilized biocatalyst has been investigated theoretically. Zero order and first order kinetics were taken into consideration. The mass balance for the substrate on a cylindrical shaped biocatalyst results into an ordinary differential equation (ODE) which can be solved numerically and/or analytically using appropnate boundary conditions. Detailed steps for analytical solutions are presented for zero and first order kinetics. The differential equation for zero and first order kinetics was changed into a dimensionless form by defining suitable dimensionless variables. The concentration profiles inside the porous biocatalyst were obtained as a function of Thiele modulus

Comparative study of bioreactors used for palm oil mill effluent treatment based on chemical oxygen removal efficiencies

The conventional treatment method for palm oil mill effluents (POME) is predominantly anaerobic system, which involves the use of various bioreactors. Some of these bioreactors have been studied for the treatment of POME at laboratory scale, though few have been applied industrially. Such bioreactors include up-flow anaerobic sludge blanket (UASB) reactor, up-flow anaerobic filtration, fluidized bed reactor, up-flow anaerobic sludge fixed-film (UASFF) reactor, anaerobic contact digester, continuous stirred tank reactor (CSTR) and membrane bioreactors. Few studies on the application of bioreactors based aerobic activated sludge reactor and evaporation method have been reported. Chemical oxygen demand (COD) is the parameter that measures the level of pollutants in wastewater, thus, this mini-review compares the various bioreactors, employ in the treatment of POME, based on their chemical oxygen demand (COD) removal efficiencies and thus envisages feasibility of introducing novel bioreactor for effective treatment of POME

Diffusion-reaction of substrate in immobilized slab biocatalyst for Michaelis-menten kinetics

The mass transfer effect on the overall reaction rate in a biocatalyst with a slab geometry containing an immobilized enzyme or cells has been investigated theoretically; Michaelis-Menten kinetics was studied. Numerical solution is used to solve the diffusion-reaction problem for Michaelis-Menten kinetics. The numerical scheme used was shooting method employing Runge-Kutta fourth order method for the solution of system of ODE-IVP. The numerical solution was validated by comparing with the exact solutions for the zero and first order reactions. A third order polynomial solution to the differential equation is also proposed. The approximate solution shows close agreement with the numerical solution within the range of parameters of practical significance. The concentration profiles within the catalyst slab were obtained as a function of Thiele modulus which in turn was used to evaluate effectiveness factor