Industrial applications of microbial lipases
Fariha Hasan ∗ , Aamer Ali Shah, Abdul Hameed
Microbiology Research Laboratory, Department of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan Received 29 April 2005; accepted 24 October 2005
Abstract Lipases are a class of enzymes which catalyse the hydrolysis of long chaintriglycerides. Microbial lipases are currently receiving much attention with the rapid development of enzyme technology. Lipases constitute the most important group of biocatalysts for biotechnological applications. This review describes various industrial applications of microbial lipases in the detergent, food, ﬂavour industry, biocatalytic resolution of pharmaceuticals, esters and amino acidderivatives, making of ﬁne chemicals, agrochemicals, use as biosensor, bioremediation and cosmetics and perfumery. © 2005 Elsevier Inc. All rights reserved.
Keywords: Lipases; Biocatalysts; Industrial application
1. Introduction Enzymes are considered as nature’s catalysts. Most enzymes today (and probably nearly all in the future) are produced by the fermentation of biobased materials . Lipidsconstitute a large part of the earth’s biomass, and lipolytic enzymes play an important role in the turnover of these water-insoluble compounds. Lipolytic enzymes are involved in the breakdown and thus in the mobilization of lipids within the cells of individual organisms as well as in the transfer of lipids from one organism to another . Microorganisms have earlier been found to produceemulsifying agents or biosurfactants to help solubilize lipids . Several thousand enzymes possessing different substrate speciﬁcities are known, however only comparatively few enzymes have been isolated in a pure form and crystallized, and little has been known about their structure and function. The advent of protein engineering techniques makes their application to important industrial enzymes,such as proteases and lipases used in detergents, amylases and glucose isomerase used in starch processing and in the bioprocessing of raw materials or in the synthesis of organic chemicals are very efﬁcient . The particular beneﬁts offered by enzymes are speciﬁcity, mild conditions and reduced waste. It may be possible, by choosing the right enzyme, to control which products are produced, andunwanted side reactions are minimized due to speciﬁcity of
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enzymes that appear in the waste stream. The plant using enzymatic reactions can be built and operated at much lower capital and energy cost. Enzyme-based processes tend to have lower waste treatment costs. Enzymeshowever are biodegradable, and since they usually are dosed at 0.1–1.0% of the substrate, the contribution of the enzyme to the BOD in the waste stream is negligible . Microbial enzymes are often more useful than enzymes derived from plants or animals because of the great variety of catalytic activities available, the high yields possible, ease of genetic manipulation, regular supply due toabsence of seasonal ﬂuctuations and rapid growth of microorganisms on inexpensive media. Microbial enzymes are also more stable than their corresponding plant and animal enzymes and their production is more convenient and safer . Only about 2% of the world’s microorganisms have been tested as enzyme sources. Bacterial strains are generally more used as they offer higher activities compared toyeasts  and tend to have neutral or alkaline pH optima and are often thermostable. Genetic and environmental manipulation to increase the yield of cells , to increase the enzyme activity of the cells by making the enzyme of interest constitutive, or by inducing it, or to produce altered enzymes , may be employed easily using microbial cells because of their short generation times, their...