Silk-Cocoon Matrix Immobilized Lipase Catalyzed Transesterification of Sunflower Oil for Production of Biodiesel

Abstract

Biodiesel from sunflower oil using lipase chemically immobilized on silk-cocoon matrix in a packed-bed bioreactor was investigated. The immobilization was demonstrated by field-emission scanning electron microscopy and activity study. The lipase loading was 738.74 U (~0.01 g lipase powder)/g-lipase-immobilized matrix. The Km (Michaelis-Menten constant) of the free and the immobilized lipase was 451.26 μM and 257.26 μM, respectively. Low Km value of the immobilized lipase is attributed to the hydrophobic nature of the matrix that facilitated the substrate diffusion to the enzyme surface. The biodiesel yield of 81.62% was obtained at 48 hours reaction time, 6 : 1 methanol : oil ratio (v/v), and 30°C. The immobilized lipase showed high operational stability at 30°C. The substrate conversion was only marginally decreased till third cycle (each of 48 hours duration) of the reaction since less than even 5% of the original activity was decreased in each of the second and third cycle. The findings demonstrated the potential of the silk-cocoon as lipase immobilization matrix for industrial production of biodiesel.

An overview of technologies for immobilization of enzymes and surface analysis techniques for immobilized enzymes

“…SEM samples are commonly used to observe the morphology to confirm success of enzyme immobilization,[ 102 , 103 ] while FESEM is used to visualize very small topographic or morphology details on the surface or entire or fractioned objects. [ 104–106 ]…”

Silk Fibroin: An Emerging Biocompatible Material for Application of Enzymes and Whole Cells in Bioelectronics and Bioanalytical Sciences

“…The reason was again attributed to the hydrophobic nature of the SF matrix that facilitated the diffusion of the hydrophobic substrate toward the enzyme. This SF-ligase matrix may have great potential in the biodiesel industries . SF (papain treated) was also used to immobilize naringinase via glutaraldehyde cross-linking.…”

“…This SF-ligase matrix may have great potential in the biodiesel industries. 61 SF (papain treated) was also used to immobilize naringinase via glutaraldehyde crosslinking. The SF support provided the stability against pH and temperature as compared to keratins from bovine horn and papain treated sheep wool and collagen.…”

Achromobacter sp. and Virgibacillus pantothenticus as models of thermo-tolerant lipase-producing marine bacteria from North Delta sediments (Egypt)

“…Microbial lipases are currently receiving much attention because of their biotechnological potential applications (Aly et al, 2012;Wang et al, 2014). They are the major industrial enzymes extensively used in pharmaceuticals, textiles, food, medical, detergent manufacturing and other chemical industries (Mohan et al, 2008;Sangeetha et al, 2011;Aly et al, 2012;Nerurkar et al, 2013;Chatterjee et al, 2014).…”