Orption of enzyme molecules. Immobilization through covalent bonds has the benefit of minimal enzyme leakage, and help like electrospun PAR2 Antagonist site polyacrylonitrile was reported [12]. Cross-linked enzyme aggregates can be formed by suggests of bifunctional or multifunctional reagents for instance glutaraldehyde [13]. Lipases is often also entrapped in polymeric matrix like phyllosilicate sol-gel [14] and silica gels [15] or encapsulated in silica aerogel [16]. Magnetic nanoparticles (MNP) has been widely applied in many fields of life science, for example, magnetic resonance imaging contrast enhancement, tissue repair, immunoassay, hyperthermia, and drug delivery [17], owing to possessing unique properties of nontoxicity, biocompatibility, injectability, and high degree of accumulation within the target tissue and organ [18]. It has been utilised as carriers for immobilizing drugs, proteins, enzymes, antibodies, and nucleotides [17]. Use of MNP as help for enzyme immobilization makes it possible for for huge surface region for possible high enzyme loading, selective separation in the reaction mixture under magnetic field, and low mass transfer resistance on account of small particle size [19]. We have previously immobilized lipase from Pseudomonas cepacia onto MNP for the synthesis of fatty acid methyl esters (FAME) with soybean oil as a feedstock [20,21].Int. J. Mol. Sci. 2013,Response surface methodology (RSM), a collection of mathematical and statistical tactics valuable for modeling and evaluation of issues in which a response of interest is influenced by several variables [22], has been widely applied to the synthesis of biodiesel. For instance, temperature, substrate molar ratio, and n-hexane content material have been optimized for the production of biodiesel applying lipase entrapped in biomimetic silica [23], or temperature, flow rate, and substrate molar ratio were optimized for continuous production of biodiesel within a MEK Activator custom synthesis lipase-catalyzed packed-bed reactor [9,24]. The production of biodiesel using immobilized lipase has been studied extensively; however, most of connected studies utilized pure vegetable oils as feedstocks [7]. In this perform, we evaluated the potential of WCO as a feedstock for the synthesis of FAME utilizing lipase immobilized on MNP as a catalyst. The crucial reaction variables (temperature, substrate molar ratio, and water content) were optimized with RSM. In addition, reusability and storage stability of immobilized enzyme were also evaluated. two. Results and Discussion 2.1. Effects of Volume of Added Lipase on Immobilization Efficiency and Activity Recovery Effects of level of added lipase on immobilization efficiency (ratio of amount of immobilized to added lipase) and activity recovery (ratio of distinct activities for immobilized to no cost lipase) are shown in Figure 1. Maximal activity recovery of 60 with the corresponding immobilization efficiency of 92.three was observed when 5 mg of lipase was added. The activity recovery decreased because the volume of lipase elevated; nevertheless, the immobilization efficiency showed little change. The reduce in activity recovery might be attributed to higher steric hindrance generated and less accessible active internet sites as additional enzyme molecules have been attached for the help. We also evaluated the external mass transfer resistance with Mears’ criterion [25]: 0.(1)will be the bulk density of catalyst; R could be the radius of catalyst particle; n exactly where – is definitely the rate of reaction; is definitely the reaction order; kc would be the mass transfer coefficient; CAb is definitely the bulk.
