Date Published: February 8, 2016
Publisher: Springer Berlin Heidelberg
Author(s): G. Garg, A. Singh, A. Kaur, R. Singh, J. Kaur, R. Mahajan.
Pectinases are the growing enzymes of biotechnological sector, showing gradual increase in their market. They hold a leading position among the commercially produced industrial enzymes. These enzymes are ecofriendly tool of nature that are being used extensively in various industries like wine industry; food industry; paper industry for bleaching of pulp and waste paper recycling; in the processing of fruit–vegetables, tea–coffee, animal feed; extraction of vegetable oil and scouring of plant fibres. Moreover, enzymatic catalysis is preferred over other chemical methods, since it is more specific, less aggressive and saves energy. This is the review which covers the information available on the applicability potential of this group of enzymes in various sectors.
The primary source of industrial enzymes is microorganisms, out of which, 50 % originate from fungi and yeast, 35 % from bacteria, while the remaining 15 % are either of plant or animal origin (Anisa and Girish 2014). The pectinases are being produced by various kinds of microorganisms (Servili et al. 1992; Kapoor et al. 2001; Angayarkanni et al. 2002; Hoondal et al. 2002; Sharma and Satyanarayana 2012; Sharma et al. 2013b; Mohamadi et al. 2014). They are also reported to be produced in combination with other industrially important enzymes by the same microbial isolate (Kaur et al. 2011; Singh et al. 2015). The pectinase enzyme is broadly classified into three types on the basis of their mode of action: pectin esterase, hydrolases and lyases. Pectin esterase catalyses the de-esterification of the methoxyl group of pectin, forming pectic acid. Hydrolases (Polygalacturonases and Polymethylgalacturonases)—Catalyses the hydrolytic cleavage of α-1,4-glycosidic linkage in pectic acid and pectin, respectively, while Lyases (Polygalacturonate Lyase and Polymethylgalacturonate Lyase)—Catalyses the cleavage of α-1,4-glycosidic linkage in pectic acid and pectin, respectively by trans-elimination reaction and forming unsaturated galacturonates and methyl galacturonates, respectively. The Classification of Pectinases, their mode of action and products formed are shown in Table 1 and Fig. 1, respectively. Pectinases can be produced by both submerged and solid state fermentation (SSF). Optimised conditions for pectinase production by various microorganisms have been shown in Table 2.Table 1Classification of pectinases (data modified from Jayani et al. 2005)E.C. suggested nameCommon nameE.C. No.SubstrateMode of action and cleavageProductDe-esterifying enzymesPolymethylgalacturonate esterase (PMGE)Pectin esterase184.108.40.206PectinRandom cleavage of methyl ester group of galacturonate unitPectic acid + methanolDe-polymerising enzymes(a) Hydrolases (i) Polygalacturonases (PG)—Catalyzes the hydrolytic cleavage of α-1,4-glycosidic linkage in pectic acidEndopolygalacturonase (endo—PG)Polygalacturonase220.127.116.11PectateRandom cleavage of pectic acidOligo-galacturonatesExopolygalacturonase 1 (exo—PG1)Polygalacturonase18.104.22.168PectateTerminal cleavage from the non reducing end of the polygalacturonic acidMono-galacturonatesExopolygalacturonase 2 (exo—PG2)Polygalacturonase22.214.171.124PectatePenultimate CleavageDi-galacturonates (ii) Polymethylgalacturonases (PMG)—Catalyses the hydrolytic cleavage of α-1,4-glycosidic linkage in pectinEndo—PMGPectin hydrolasePectinRandom cleavageOligo methyl-galacturonatesExo—PMGPectin hydrolasePectinTerminal cleavage from the non-reducing end of pectinMethyl mono-galacturonate(b) Lyases (i) Polygalacturonate Lyase (PGL)—Catalyses the cleavage of α-1,4-glycosidic linkage in pectic acid by trans-elimination forming unsaturated galacturonatesEndo—PGLPectate lyase126.96.36.199PectateRandom cleavageUnsaturated oligo-galacturonatesExo—PGLPectate lyase188.8.131.52PectateCleavage of penultimate bonds from non-reducing endUnsaturated di-galacturonatesOligogalacturonate lyasePectate lyase184.108.40.206Oligo-galacturonateTerminal cleavageUnsaturated mono-galacturonates (ii) Polymethylgalacturonate Lyase (PMGL)—Catalyses cleavage of α-1,4-glycosidic linkage in pectin by trans-elimination forming unsaturated methyl galacturonates at the non-reducing endEndo –PMGLPectin lyase220.127.116.11PectinRandom cleavageUnsaturated methyl oligo-galacturonatesExo—PMGLPectin lyasePectinTerminal cleavageUnsaturated methyl mono-galacturonatesFig. 1Mode of action and products of pectinases (Lang and Dornenburg 2000). Mode of action of pectinases: a R=H for PG (Polygalacturonases) and CH3 for PMG (Polymethylgalacturonases), b PE (Pectin esterase), c R=H for PGL (Polygalacturonate lyase) and CH3 for PL (Pectin lyase). The arrow indicates the mode of action of different forms of pectinases. Products of pectinases: a Saturated galacturonic acid formed by PG and Saturated methoxylated galacturonide by PMG, b Pectic acid formed by PE, c Unsaturated galacturonic acid formed by PGL and unsaturated methoxylated galacturonide by PLTable 2Fermentation conditions for pectinase production by various microorganismsMicroorganismSubstrateFermentationReferencesTypeTemperature (°C)pHAspergillus niger A 138SucroseSmF324.5Friedrich et al. (1990)Aspergillus niger 3T5B8Wheat branSSF32–Couri et al. (2000)Bacillus sp. DT7PectinSmF377.2Kashyap et al. (2000)Penicillium veridicatum RFC3Orange bagasse, Wheat branSSF30–Silva et al., 2002Bacillus sp. DT7Wheat branSSF37–Kashyap et al. (2003)Aspergillus fumigatesWheat branSSF50–Phutela et al. (2005)Aspergillus nigerSunflower headSSF305.0Patil and Dayanand (2006)Aspergillus fumigatus MTCC 870Wheat flourSmF305.0Palaniyappan et al. (2009)Penicillium chrysogenumSucroseSmF356.5Banu et al. (2010)Aspergillus heteromorphusOrange peelSmF304.5Mandhania et al. (2010)Thermomucor indicae-seudaticaeWheat bran, Orange bagasseSSF45–Martin et al. (2010)Penicillium sp.PectinSSF356.0Patil and Chaudhari (2010)Fomes sclerodermeusSoy and Wheat branSSF28–Salariato et al. (2010)Bacillus subtilisPectinSmF507.0Swain and Ray (2010)Bacillus sp. AD 1PectinSmF377.0Dey et al. (2011)Aspergillus nigerPectinSmF375.5Gomes et al. (2011)Aspergillus sojae M3Orange peelSSF22–Demir et al. (2012)Aspergillus flavusOrange peelSSF405.5Johnson et al. (2012)Penicillium atrovenetumOrange peel SSF 405.0Johnson et al. (2012) Aspergillus oryzaeOrange peel SSF 355.5Johnson et al. (2012) Bacillus subtilisDate syrupSmF458.0Qureshi et al. (2012)Pseudozyma sp. SPJCitrus peelSSF327.0Sharma et al. (2012)Mixed culture of Aspergillus fumigatus,Aspergillus sydowiiPineapple residueSSF355.0Singh and Mandal (2012)Aspergillus nigerSour oranges peelSSF305.0Vasanthi and Meenakshisundaram (2012)Streptomyces sp.PectinSmF308.5Das et al. (2013)Penicillium citrinumSugar beet pulpSSF305.5EI-Batal et al. (2013)Erwinia carotovoraPectinSmF355.2Kothari and Baig (2013)Bacillus firmusPectinSmF507.0Roosdiana et al. (2013)Aspergillus nigerDate pomaceSmF–6.18Seifollah and Khodaverdi (2013)Rhizomucor pusillusPectinSSF455.0Siddiqui et al. (2013)Rhodotorula glutinis MP-10Citrus pectinSmF305.5Taskin (2013)Aspergillus sojaeWheat branSSF376.0Demir and Tari (2014)Aspergillus niger HFD5A-1citrus pectinSmF304.5Ibrahim et al. (2014)Trichoderma viridiOrange peelSSF305.5Irshad et al. (2014)
The first commercial application of pectinases was reported in 1930 by Kertesz for the clarification of apple juice. List of companies producing commercial pectinases is given in Table 3. The application aspect of pectinases has been discussed under the following heads (Fig. 2).Table 3List of companies producing commercial pectinases (Data modified from Kashyap et al. 2001a)Product trade nameManufacturerPectinaseBiocon Pvt Ltd, IndiaPectolaseGrinsteelvaeket, DenmarkPectinase MashNovozyme, DenmarkUltrazymeCiba-Geigy A.G., SwitzerlandKlerzymeClarizyme Wallerstein, Co., USAMaxLiqDanisco, DenmarkSclaseKikkoman Shoyu, Co., JapanPectinexSchweizerische Ferment, A.G., SwitzerlandPectinex Ultra SP-L and Pectinex CLEARNovo Nordisk Ferment Ltd., SwitzerlandPectinolRohm, GmbH, West GermanyLy Peclyve PRLyven, FrancePanzymC.H. Boehringer Sohn, West GermanyRohapect MA PlusAB Enzymes, FinlandRapidaseSociete Rapidase, S.A., FranceSolpect L 60Varuna Biocell Pvt. Ltd., IndiaFood Grade Pectinase Unikbio Biotech Ltd., ChinaFig. 2Applications of pectinases in various industries
Microbial pectinases are the leading enzyme of the industrial sector. They are being used extensively for various industrial applications and new applications are still coming up. But the main consideration is of enzyme titre and/or stability of the enzyme to make the process cost effective. Production of pectinases has been reported by many workers and cost-effective substrates have also been used but still the production cost is high either due to low activity or instability of enzyme at high temperature for longer duration. So, storage of enzyme at low temperature further increases its cost for industrial application.