Nitin W. Fadnavis

Bio: Nitin W. Fadnavis is an academic researcher from Indian Institute of Chemical Technology. The author has contributed to research in topics: Immobilized enzyme & Lipase. The author has an hindex of 17, co-authored 68 publications receiving 995 citations.

Efficient Immobilization of Lecitase in Gelatin Hydrogel and Degumming of Rice Bran Oil Using a Spinning Basket Reactor

Abstract: Immobilization of Lecitase (Phospholipase A1) in gelatin hydrogel and its stability is studied with a view to utilizing the immobilized enzyme for degumming rice bran oil. Excellent retention of enzyme activity ((80%) is observed in hydrogel containing 43.5% gelatin crosslinked with glutaraldehyde. Compared to the free enzyme which has a broad pH-activity profile (6.5-8.0), the activity of the immobilized enzyme is strongly dependent on pH and has a pH-optimum of pH 7.5. The optimum temperature of enzyme activity increases from 37 to 50 C. Compared to the free enzyme which loses all its activity in 72 h at 50 C, the immobilized enzyme retains its activity in full. The immobilized enzyme has been used efficiently in a spinning basket bioreactor for the degumming of rice bran oil with 6 recycles without loss of enzyme activity. The phosphorus content of the oil decreases from 400 ppm to 50-70 ppm in each cycle. After charcoal treatment and dewaxing, a second enzymatic treatment brings down the phosphorus content to \5 ppm.

Lipase activity of Lecitase® Ultra: characterization and applications in enantioselective reactions

Abstract: The general properties of Lecitase® Ultra, a phospholipase manufactured and marketed by Novozymes, Denmark, have been studied after purification by ultrafiltration. The enzyme has a molecular mass of 35 KD, pH-optimum of 8.5, and appears to possess a single active site which exhibits both the lipase and phospholipase activities that increase in the presence of Ca 2+ and Mg 2+ ions. The enzyme is inhibited by heavy metal ions and surfactants, and does not accept p -nitrophenyl acetate and glycerol triacetate. Substrates, such as glycerol tributyrate and p -nitrophenyl palmitate, esters of N -acetyl-α-amino acids and α-hydroxy acids are readily accepted. Amino acids with aliphatic residues, such as alanine, isoleucine, and methionine, are hydrolyzed with high enantioselectivity for the l -enantiomer ( E >100), but amino acids with aromatic residues such as phenylalanine and phenylglycine, and esters of α-hydroxy acids are hydrolyzed with low enantioselectivity ( E = 1–5). Immobilization of the enzyme in a gelatin matrix (gelozyme) leads to a marginal improvement in the enantioselectivity for these substrates. However, a dramatic improvement in enantioselectivity is observed for ethyl 2-hydroxy-4-oxo-4-phenylbutyrate ( E value increases from 4.5 to 19.5 with S -selectivity). Similarly, glycidate esters, such as ethyl trans -(±)-3-phenyl glycidate and methyl trans -(±)-3-(4-methoxyphenyl) glycidate, are selectively hydrolyzed with a remarkable selectivity towards the (2 S ,3 R )-enantiomer providing unreacted (2 R ,3 S )-glycidate esters (ee >99%, conversion 52–55%) by the immobilized enzyme.

Gelatin blends with alginate: gels for lipase immobilization and purification.

Abstract: Blends of natural polysaccharide sodium alginate (5%) with gelatin (3%) cross-linked with glutaraldehyde provide beads with excellent compressive strength (8 x 10(4) Pa) and regular structure on treatment with calcium chloride. Lipases from porcine pancreas, Pseudomonas cepacia, and Candida rugosa were immobilized in such a blend with excellent efficiency. The immobilized enzymes were stable and were reused several times without significant loss of enzyme activity both in aqueous and reverse micellar media. The beads were functionalized with succinic anhydride to obtain beads with extra carboxylic acid groups. These functionalized beads were then successfully used for 7.4-fold purification of crude porcine pancreatic lipase in a simple operation of protein binding at pH 5 and release at pH 8.5.

Resolution of racemic 2-amino-1-butanol with immobilised penicillin G acylase†

Abstract: Racemic 2-amino-1-butanol has been resolved to obtain ( S )-2-amino-1-butanol with >99% e.e. via enantioselective hydrolysis of its N -phenylacetyl derivative with penicillin G acylase immobilised on Eupergit C.

Potential of Different Enzyme Immobilization Strategies to Improve Enzyme Performance

Abstract: Enzyme biocatalysis plays a very relevant role in the development of many chemical industries, e.g., energy, food or fine chemistry. To achieve this goal, enzyme immobilization is a usual pre-requisite as a solution to get reusable biocatalysts and thus decrease the price of this relatively expensive compound. However, a proper immobilization technique may permit far more than to get a reusable enzyme; it may be used to improve enzyme performance by improving some enzyme limitations: enzyme purity, stability (including the possibility of enzyme reactivation), activity, specificity, selectivity, or inhibitions. Among the diverse immobilization techniques, the use of pre-existing supports to immobilize enzymes (via covalent or physical coupling) and the immobilization without supports [enzyme crosslinked aggregates (CLEAs) or crystals (CLECs)] are the most used or promising ones. This paper intends to give the advantages and disadvantages of the different existing immobilization strategies to solve the different aforementioned enzyme limitations. Moreover, the use of nanoparticles as immobilization supports is achieving an increasing importance, as the nanoparticles versatility increases and becomes more accessible to the researchers. We will also discuss here some of the advantages and drawbacks of these non porous supports compared to conventional porous supports. Although there are no universal optimal solutions for all cases, we will try to give some advice to select the optimal strategy for each particular enzyme and process, considering the enzyme properties, nature of the process and of the substrate. In some occasions the selection will be compulsory, for example due to the nature of the substrate. In other cases the optimal biocatalyst may depend on the company requirements (e.g., volumetric activity, enzyme stability, etc).

Ordered Mesoporous Materials for Bioadsorption and Biocatalysis

Abstract: The encapsulation of enzymes and other proteins into inorganic host materials has attracted considerable attention over the past few years This research has demonstrated that biomolecules immobilized in inorganic matrixes retain their functional characteristics to a large extent These new materials are of interest for applications as (optically based) biosensors and biocatalysts We review the growing field of amino acids, vitamins, enzymes, and whole cells adsorbed (immobilized) onto ordered mesoporous silica and carbon molecular sieves Strategies for the preparation of mesoporous supports and the essential properties of the resulting materials with respect to the envisaged applications are presented Basic effects of the nature of the adsorption and various aspects of the application of these materials as biosensors, bicatalysts, and for drug release are discussed Outlook of potential applications and further challenges are also provided

Role of Biocatalysis in Sustainable Chemistry

Abstract: Based on the principles and metrics of green chemistry and sustainable development, biocatalysis is both a green and sustainable technology. This is largely a result of the spectacular advances in molecular biology and biotechnology achieved in the past two decades. Protein engineering has enabled the optimization of existing enzymes and the invention of entirely new biocatalytic reactions that were previously unknown in Nature. It is now eminently feasible to develop enzymatic transformations to fit predefined parameters, resulting in processes that are truly sustainable by design. This approach has successfully been applied, for example, in the industrial synthesis of active pharmaceutical ingredients. In addition to the use of protein engineering, other aspects of biocatalysis engineering, such as substrate, medium, and reactor engineering, can be utilized to improve the efficiency and cost-effectiveness and, hence, the sustainability of biocatalytic reactions. Furthermore, immobilization of an enzyme ...

Potential applications of oxidative enzymes and phenoloxidase-like compounds in wastewater and soil treatment: a review

Abstract: A number of oxidative enzymes from bacteria, fungi and plants have been reported to play an important role in numerous waste treatment applications. Peroxidases and/or phenoloxidases can act on specific recalcitrant pollutants by precipitation or transforming to other products and permitting a better final treatment of the waste. Improvement in the useful life and thereby a reduction in treatment cost has been accomplished through enzyme immobilization. Horseradish peroxidase, lignin peroxidase and manganese peroxidase mineralize a variety of recalcitrant aromatic compounds. Immobilization of these enzymes on porous ceramic supports or resins did not adversely affect their stability and showed a good potential for degradation of environment persistent aromatics. Tyrosinase, which catalyzes the hydroxylation of phenols and dehydrogenation of o-diphenols, in an immobilized form exerted an excellent phenol removal. Laccase is capable of eliminating the phenols through polymerization process, however, the presence of mediator such as ABTS and HBT degraded phenol by oxidative process. Many applications with oxidative enzymes and plant materials in effluent as in soil remediation will be discussed.