Int. No, water-based polyurethane is not toxic. implied warranty of any kind. Rapid Commun. (2017). The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Sci. Consequently, they have become ubiquitous in the global economy (Barnes et al., 2009; Andrady, 2011; Hidalgo-Ruz et al., 2012). 27, 205222. Biochem. The identities of enzymes involved in the degradation petro-polymers like PE and PP, and the mechanisms of these enzyme-substrate interactions, are largely unknown. 36, 10151049. The use of the blends facilitates adhesion of the microorganisms to the surface of the polymer and acts as a co-metabolite (Cacciari et al., 1993; Zuchowska et al., 1998; Ramis et al., 2004; Kaczmarek et al., 2005; Morancho et al., 2006). Res. Neufeld, L., Stassen, F., Sheppard, R., and Gilman, T. (2016). Degrad. PE usually has a semi-crystalline structure and is extremely resistant to biodegradation. Microbiol. are intended for guidance in a polymer selection process and should not be considered (Rajandas et al., 2012), and fungi, such as Aspergillus and Fusarium (Hasan et al., 2007; Sahebnazar et al., 2010), were shown to depolymerize PE after some forms of pretreatment such as Ultraviolet (UV) and/or thermal treatments, which render the carbon chains of polymer sensitive to biodegradation (Ammala et al., 2011). Selected properties of major synthetic thermoplastic polymers (Ojeda, 2013). doi: 10.1021/acs.est.5b02663, Yin, C.-F., Xu, Y., and Zhou, N.-Y. Acta 1647, 98102. Microbiol. BEnzym. Yang et al. (2018a). (2019). Stabilization of polyurethane elastomers against ozonolytic degradation using stabilizers. Environ. Enzymatic degradation of polystyrene by hydroquinone peroxidase of Azotobacter beijerinckii HM121. 
doi: 10.1016/j.polymdegradstab.2010.03.009, Franden, M. A., Jayakody, L. N., Li, W.-J., Wagner, N. J., Cleveland, N. S., Michener, W. E., et al. Polymer chains are broken by enzymes secreted by the microbes, and the hydrolysis products are taken up and metabolized. Stab. 11, 9398. (2013). 42, 76967701. Pollut. Yoon et al. J. Mol. (2004). In recent years, biodegradation of other petro-plastics, like PE and PS, insect larvae such as Yellow Mealworms (Tenebrio molitor) (Billen et al., 2020), Dark Mealworms (Tenebrio obscurus) (Brandon et al., 2018; Peng et al., 2019), Superworms (Zophobas atratus) (Peng et al., 2020b), Lesser Waxworms (Achroia Grisella) (Kundungal et al., 2019), and by snails (Achatina fulita) (Song et al., 2020), have been reported. Turbidimetric analysis of the enzymatic hydrolysis of polyethylene terephthalate nanoparticles. Metall. 129, 3942. 64, 493501. Part A Polym. doi: 10.1007/s10924-007-0066-3, Tokiwa, Y., Calabia, B. P., Ugwu, C. U., and Aiba, S. (2009). doi: 10.1128/AEM.24.6.911-919.1972, Gorghiu, L. M., Jipa, S., Zaharescu, T., Setnescu, R., and Mihalcea, I. Polym. Some of these are: * Hydrolysis * Thermolysis * Oxidation * Photolysis * Pyrolysis * Microbial * The polyester polyurethanase gene (pueA) from Pseudomonas chlororaphis encodes a lipase. doi: 10.1016/j.polymdegradstab.2005.04.029, Motta, O., Proto, A., De Carlo, F., De Caro, F., Santoro, E., Brunetti, L., et al. The promiscuous activity of alpha-amylase in biodegradation of low density polyethylene in a polymer-starch blend. 
Biodegrad. Appl. J. Biotechnol. Chem. However, to date, no specific enzymes with the ability to biodegrade PE, PS, PP, or PVC have been well characterized, and the mechanisms of degradation the covalent bonds in carbon backbone petro-polymers are currently unknown. Biodeterior. Degradability of linear polyolefins under natural weathering. 98, 78157823. (1991). The growing amount of plastic waste has become a global concern. . 65, 111. Microb. Eng. Polym. In case of P. putida U and P. aeruginosa, the Pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenases involved are the PedE and PedH, and the ExaA (formerly QedH) enzymes (Arias et al., 2008). Stab. Technol. 24, 911919. 10:489. doi: 10.3389/fmicb.2019.00489, Yang, J., Yang, Y., Wu, W. M., Zhao, J., and Jiang, L. (2014). Polyethylene terephthalate (PET) and polyurethane (PU) plastics have heteroatoms in the main chain. These periplasmic enzymes have been found essential for growth utilizing ethanol as a carbon source, since it catalyzes the oxidation of the substrate into acetaldehyde (Gorisch, 2003). This branching system makes LDPE chains more accessible and the tertiary carbon atoms at the branch sites more susceptible to attack. 25, 243250. (2018) used Markov Model-based search strategy to show that a surprisingly large variety of potential polyesterases still needs to be discovered particularly in bacteria, which are currently not considered as a prime source for cutinases (Danso et al., 2018). 59, 36953700. Nat. (2020a). R. Soc. Environ. doi: 10.1016/j.ymben.2018.06.003, Gajendiran, A., Krishnamoorthy, S., and Abraham, J. The quantum efficiency of spectral UV on photodegration of an acrylic-urethane coating has been investigated. 42, 578586. Int. Firstly, a surface-binding domain promotes hydrophobic adsorption of PudA to the PU surface and, hydrolysis of ester bonds forms the second step (Akutsu et al., 1998). Biological degradation of plastics: a comprehensive review. PpEst is a novel PBAT degrading polyesterase identified by proteomic screening of Pseudomonas pseudoalcaligenes. Enzymatic surface hydrolysis of PET: effect of structural diversity on kinetic properties of cutinases from Thermobifida. Benzophenones are good general-purpose UV absorbers for clear polyolefin systems, and can also be used in pigmented compounds. Int. (2014). 110, 25812590. 292, 51285143. (2017). Biotechnological conversion of PET through pyrolysis and conversion to polyhydroxyalkanoate has been demonstrated using different Pseudomonads (Ward et al., 2006; Kenny et al., 2008; Guzik et al., 2014). The ability of the white rot fungi to degrade the organopollutants to carbon dioxide, has been shown to be dependent on a nonspecific, non-stereo-selective lignin degrading system. Microorganisms participating in the biodegradation of modified polyethylene films in different soils under laboratory conditions. They suggested that the intestinal microbiomes of these insect larvae play key role in the initial short-term biodegradation process, which occurs rapidly within the larval insect gut. The SAC removal in real water matrices by UV/PS treatment was still relatively efficient. (2020b). Degrad. Chem. doi: 10.1021/acs.est.9b07044, Marques-Calvo, M. S., Cerda-Cuellar, M., Kint, D. P. R., Bou, J. J., and Munoz-Guerra, S. (2006). 48, 197207. A review. Pseudomonas putida strain AJ was reported to use vinyl chloride monomers as carbon source for growth (Verce et al., 2000). Int. Lett. 25, 243250. The processes of photooxidative degradation is less expressed in polyesterurethane then in polyurethane based on polyether, under the same conditions Biodegradation of polyethylene and plastic mixtures in mealworms (Larvae of Tenebrio molitor) and effects on the gut microbiome. WebThe SAC degradation by UV/PS was mainly initiated through the hydroxylation of the benzene ring, cleavage of C-N bonds, decarboxylation and denitrogenation. doi: 10.3390/ijms10093722, Torikai, A., and Hasegawa, H. (1999). doi: 10.1016/j.nbt.2019.04.005, Gilan, I., Hadar, Y., and Sivan, A. The PHAs are synthesized and accumulated by many prokaryotic microorganisms as storage compounds for carbon and energy when a major non-carboneous nutrient (e.g., nitrogen or phosphorus) is limiting. 33, 103113. Biodegrad. Biochim. Once in the cells, these degradation products are channelled through the classical catabolic pathways to yield energy and reducing power for cell growth. (2014). G. Pritchard (Dordrecht: Springer). It is presumed that large, high molecular weight polymers are first degraded by extracellular enzymes, secreted by microorganisms, into smaller subunits (oligomers and/or dimers) that can be incorporated into the microbial cells. 324, 634644. Polymers and the environment, in Polymer Science, ed. 5:171792. doi: 10.1098/rsos.171792, Hasan, F., Shah, A. Biotechnol. Environ. J. Appl. A polyesterase capable of hydrolyzing aromatic polyesters (primarily PET) was first reported from Thermobifida fusca by a German research group (Mller et al., 2005). J. Environ. Bombelli et al. J. Bioremed. Biosci. Environ. Biodegradation of plastics: current scenario and future prospects for environmental safety. Microbiol. Based on these knowledge, genetic engineering approaches to create recombinant microbial strains and/or enzymes could be adopted as the preferred strategy to enhance biodegradation of the synthetic petroleum based plastic waste. The ester bonds in petro-plastic polymers are the same as ester bonds in other polyester polymers, and enzymes that cleave ester bonds are known as esterases. Macromol. A dense biofilm and a decrease in mean molecular weight (Mn) has been reported as proof of polymer chain biodegradation (Das et al., 2012; Wilkes and Aristilde, 2017; Syranidou et al., 2017; Ahmed et al., 2018). (2007). New evidences of accelerating degradation of polyethylene by starch. Isolation and characterization of a bacterium which utilizes polyester polyurethane as a sole carbon and nitrogen source. 28, 681685. Effect of short wavelength UV-irradiation on ageing of polypropylene/cellulose compositions. Proc. Sci. A quantum mechanism study of the C-C bond cleavage to predict the bio-catalytic polyethylene degradation. Bacteria in the gut of the greater wax worm, Galleria melonella have been found capable of hydrolyzing polyethylene (PE) (Yang et al., 2014; Bombelli et al., 2017; Cassone et al., 2020). Crit. 185, 163168. Nikolic, V., Sava, V., Dusan, A., and Aleksander, P. (2013). A review of plastic waste biodegradation. PS materials used in these studies range from pure PS or modified PS to PS blended with other polymers. Yang et al. doi: 10.1016/S0141-3910(98)00212-2, Zuchowska, D., Steller, R., and Meissner, W. (1998). 38, 863869. Photo-degradation is a process whereby the polymer chains in the product break down due to exposure to UV radiation. H. E.-D. Saleh, London: InTech. An overview of degradable and biodegradable polyolefins. Degrad. Sameh, A. S., Alariqi, Pradeep Kumar, A., Rao, B. S. M., and Singh, R. P. (2006). doi: 10.1007/s00253-011-3402-4, Barnes, D. K. A., Galgani, F., Thompson, R. C., and Barlaz, M. (2009). Stab. Synergistic effect of photo and chemical treatment on the rate of biodegradation of low density polyethylene by Fusarium sp. As a result of their massive accumulation in municipal waste systems, micro- and nano-sized plastic particles are now ubiquitous in both terrestrial and aquatic ecosystems (lvarez-Hernndez et al., 2019; Bergmann et al., 2019). doi: 10.1016/0964-8305(93)90002-J, Ali, M. I., Ahmed, S., Javed, I., Ali, N., Atiq, N., Hameed, A., et al. Currently, several organic UV stabilizers with different maximum absorption bonds are produced commercially. Biodegrad. strain NyZ450 and Bacillus sp. Technol. Int. The lignin degrading system includes a group of peroxidases known as Ligninases, which catalyze the initial oxidative depolymerization of lignin polymers (Bumpus and Aust, 1987; Bumpus et al., 1988; Shah et al., 1992). Polyhydroxyalkanoates (PHAs) have emerged as a sustainable choice due to their putative high biodegradability in different environments, biocompatibility, chemical diversity, their manufacture from renewable carbon resources, and release of non-polluting and non-toxic products after degradation (Bhatia et al., 2019a, b). doi: 10.1128/mBio.00570-17, Wei, R., Oeser, T., Barth, M., Weigl, N., Lbs, A., Schulz-Siegmund, M., et al. the Polymer Selector including but not limited to material suitability, material Cutinases have also been reported to hydrolyse aliphatic polyesters e.g., PCL (Kleeberg et al., 2005; Baker et al., 2012) as well as aliphatic aromatic co-polyesters such as PET (Herrero Acero et al., 2011; Ribitsch et al., 2012a; Roth et al., 2014; Wei et al., 2014b; Gamerith et al., 2017) and polytrimethylene terephthalate (PTT) (Eberl et al., 2009). 26, 246265. Poll. FEBS J. (1998). The leather treated with the FPU waterproong agent was placed under a 365 nm UV lamp with a power of 30 W, which was located 0.14 m from the light source. Microbiol. 3:e1700782. Microbial degradation of untreated PE has been reported in few others such as Pseudomonas putida IRN22, Acinetobacter pittii IRN19, Micrococcus luteus IRN20 (Montazer et al., 2019) and different species of Pseudomonas, Pseudomonas aeruginosa PAO1, P. aeruginosa ATCC, P. putida, and Pseudomonas syringae (Kyaw et al., 2012), Pseudomonas sp. Biodegrad. Degradation of polypropylene-poly L lactide blend by bacteria isolated from compost. doi: 10.1007/s00253-013-5489-2, Haernvall, K., Zitzenbacher, S., Wallig, K., Yamamoto, M., Schick, M. B., Ribitsch, D., et al. (2012a). Data and information contained in the Polymer Selector Rather, both the insect digestive system and the larval gut microbiome are required to achieve accelerated biodegradation of the PE polymers. Bull. Technol. J. Bacterial degradation of polyester polyurethane. Trans. J. Polym. doi: 10.1111/j.1462-2920.2009.01948.x, Ronqvist, M., Xie, W., Lu, W., and Gross, R. A. Figure 5. Owen, J. 6:52. doi: 10.1007/s13205-016-0394-x, Gamerith, C., Herrero Acero, E., Pellis, A., Ortner, A., Vielnascher, R., Luschnig, D., et al. Prog. 37, 44944499. Protein engineering studies on cutinases (Silva et al., 2011; Herrero Acero et al., 2013) and fusion to binding domains (Zhang et al., 2010; Ribitsch et al., 2013, 2015) have demonstrated enhanced polymer degradation. Early microbial biodegradation experiments attempted to demonstrate that microbial activity could result in changes in the physical characteristics of plastics, such as tensile strength, crystallinity, and water uptake (Pirt, 1980; Albertsson and Karlsson, 1990). Rep. 9:2612. doi: 10.1038/s41598-019-39366-0, Kataoka, M., Sasaki, M., Hidalgo, A. R., Nakano, M., and Shimizu, S. (2001). Ethylene glycol metabolism by Pseudomonas putida. Microbiol. Polym. Microbiol. doi: 10.1128/AEM.02773-17, Das, G., Bordoloi, N. K., Rai, S. K., Mukherjee, A. K., and Karak, N. (2012). There are many different types of esterase, which differ in their protein structure, substrate specificity, and biological functions. Biodegradation of Polycaprolactone (PCL) blended PP has also been demonstrated using lipase since lipase is well known to degrade the ester linkages of PCL (Weiland et al., 1995). Microbiol. doi: 10.17706/ijbbb.2017.7.4.245-251. J. Biosci. Degrad. Glyoxylate can be further metabolized by the Glyoxylate carboligase B (GclB) enzyme or AceA enzyme involved in the glyoxylate shunt (Blank et al., 2008) yielding two molecules of CO2 and two reducing equivalents. 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doi: 10.1016/j.polymdegradstab.2010.03.009, Franden, M. A., Jayakody, L. N., Li, W.-J., Wagner, N. J., Cleveland, N. S., Michener, W. E., et al. Polymer chains are broken by enzymes secreted by the microbes, and the hydrolysis products are taken up and metabolized. Stab. 11, 9398. (2013). 42, 76967701. Pollut. Yoon et al. J. Mol. (2004). In recent years, biodegradation of other petro-plastics, like PE and PS, insect larvae such as Yellow Mealworms (Tenebrio molitor) (Billen et al., 2020), Dark Mealworms (Tenebrio obscurus) (Brandon et al., 2018; Peng et al., 2019), Superworms (Zophobas atratus) (Peng et al., 2020b), Lesser Waxworms (Achroia Grisella) (Kundungal et al., 2019), and by snails (Achatina fulita) (Song et al., 2020), have been reported. Turbidimetric analysis of the enzymatic hydrolysis of polyethylene terephthalate nanoparticles. Metall. 129, 3942. 64, 493501. Part A Polym. doi: 10.1007/s10924-007-0066-3, Tokiwa, Y., Calabia, B. P., Ugwu, C. U., and Aiba, S. (2009). doi: 10.1128/AEM.24.6.911-919.1972, Gorghiu, L. M., Jipa, S., Zaharescu, T., Setnescu, R., and Mihalcea, I. Polym. Some of these are: * Hydrolysis * Thermolysis * Oxidation * Photolysis * Pyrolysis * Microbial * The polyester polyurethanase gene (pueA) from Pseudomonas chlororaphis encodes a lipase. doi: 10.1016/j.polymdegradstab.2005.04.029, Motta, O., Proto, A., De Carlo, F., De Caro, F., Santoro, E., Brunetti, L., et al. The promiscuous activity of alpha-amylase in biodegradation of low density polyethylene in a polymer-starch blend. Biodegrad. Appl. J. Biotechnol. Chem. However, to date, no specific enzymes with the ability to biodegrade PE, PS, PP, or PVC have been well characterized, and the mechanisms of degradation the covalent bonds in carbon backbone petro-polymers are currently unknown. Biodeterior. Degradability of linear polyolefins under natural weathering. 98, 78157823. (1991). The growing amount of plastic waste has become a global concern. . 65, 111. Microb. Eng. Polym. In case of P. putida U and P. aeruginosa, the Pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenases involved are the PedE and PedH, and the ExaA (formerly QedH) enzymes (Arias et al., 2008). Stab. Technol. 24, 911919. 10:489. doi: 10.3389/fmicb.2019.00489, Yang, J., Yang, Y., Wu, W. M., Zhao, J., and Jiang, L. (2014). Polyethylene terephthalate (PET) and polyurethane (PU) plastics have heteroatoms in the main chain. These periplasmic enzymes have been found essential for growth utilizing ethanol as a carbon source, since it catalyzes the oxidation of the substrate into acetaldehyde (Gorisch, 2003). This branching system makes LDPE chains more accessible and the tertiary carbon atoms at the branch sites more susceptible to attack. 25, 243250. (2018) used Markov Model-based search strategy to show that a surprisingly large variety of potential polyesterases still needs to be discovered particularly in bacteria, which are currently not considered as a prime source for cutinases (Danso et al., 2018). 59, 36953700. Nat. (2020a). R. Soc. Environ. doi: 10.1016/j.ymben.2018.06.003, Gajendiran, A., Krishnamoorthy, S., and Abraham, J. The quantum efficiency of spectral UV on photodegration of an acrylic-urethane coating has been investigated. 42, 578586. Int. Firstly, a surface-binding domain promotes hydrophobic adsorption of PudA to the PU surface and, hydrolysis of ester bonds forms the second step (Akutsu et al., 1998). Biological degradation of plastics: a comprehensive review. PpEst is a novel PBAT degrading polyesterase identified by proteomic screening of Pseudomonas pseudoalcaligenes. Enzymatic surface hydrolysis of PET: effect of structural diversity on kinetic properties of cutinases from Thermobifida. Benzophenones are good general-purpose UV absorbers for clear polyolefin systems, and can also be used in pigmented compounds. Int. (2014). 110, 25812590. 292, 51285143. (2017). Biotechnological conversion of PET through pyrolysis and conversion to polyhydroxyalkanoate has been demonstrated using different Pseudomonads (Ward et al., 2006; Kenny et al., 2008; Guzik et al., 2014). The ability of the white rot fungi to degrade the organopollutants to carbon dioxide, has been shown to be dependent on a nonspecific, non-stereo-selective lignin degrading system. Microorganisms participating in the biodegradation of modified polyethylene films in different soils under laboratory conditions. They suggested that the intestinal microbiomes of these insect larvae play key role in the initial short-term biodegradation process, which occurs rapidly within the larval insect gut. The SAC removal in real water matrices by UV/PS treatment was still relatively efficient. (2020b). Degrad. Chem. doi: 10.1021/acs.est.9b07044, Marques-Calvo, M. S., Cerda-Cuellar, M., Kint, D. P. R., Bou, J. J., and Munoz-Guerra, S. (2006). 48, 197207. A review. Pseudomonas putida strain AJ was reported to use vinyl chloride monomers as carbon source for growth (Verce et al., 2000). Int. Lett. 25, 243250. The processes of photooxidative degradation is less expressed in polyesterurethane then in polyurethane based on polyether, under the same conditions Biodegradation of polyethylene and plastic mixtures in mealworms (Larvae of Tenebrio molitor) and effects on the gut microbiome. WebThe SAC degradation by UV/PS was mainly initiated through the hydroxylation of the benzene ring, cleavage of C-N bonds, decarboxylation and denitrogenation. doi: 10.3390/ijms10093722, Torikai, A., and Hasegawa, H. (1999). doi: 10.1016/j.nbt.2019.04.005, Gilan, I., Hadar, Y., and Sivan, A. The PHAs are synthesized and accumulated by many prokaryotic microorganisms as storage compounds for carbon and energy when a major non-carboneous nutrient (e.g., nitrogen or phosphorus) is limiting. 33, 103113. Biodegrad. Biochim. Once in the cells, these degradation products are channelled through the classical catabolic pathways to yield energy and reducing power for cell growth. (2014). G. Pritchard (Dordrecht: Springer). It is presumed that large, high molecular weight polymers are first degraded by extracellular enzymes, secreted by microorganisms, into smaller subunits (oligomers and/or dimers) that can be incorporated into the microbial cells. 324, 634644. Polymers and the environment, in Polymer Science, ed. 5:171792. doi: 10.1098/rsos.171792, Hasan, F., Shah, A. Biotechnol. Environ. J. Appl. A polyesterase capable of hydrolyzing aromatic polyesters (primarily PET) was first reported from Thermobifida fusca by a German research group (Mller et al., 2005). J. Environ. Bombelli et al. J. Bioremed. Biosci. Environ. Biodegradation of plastics: current scenario and future prospects for environmental safety. Microbiol. Based on these knowledge, genetic engineering approaches to create recombinant microbial strains and/or enzymes could be adopted as the preferred strategy to enhance biodegradation of the synthetic petroleum based plastic waste. The ester bonds in petro-plastic polymers are the same as ester bonds in other polyester polymers, and enzymes that cleave ester bonds are known as esterases. Macromol. A dense biofilm and a decrease in mean molecular weight (Mn) has been reported as proof of polymer chain biodegradation (Das et al., 2012; Wilkes and Aristilde, 2017; Syranidou et al., 2017; Ahmed et al., 2018). (2007). New evidences of accelerating degradation of polyethylene by starch. Isolation and characterization of a bacterium which utilizes polyester polyurethane as a sole carbon and nitrogen source. 28, 681685. Effect of short wavelength UV-irradiation on ageing of polypropylene/cellulose compositions. Proc. Sci. A quantum mechanism study of the C-C bond cleavage to predict the bio-catalytic polyethylene degradation. Bacteria in the gut of the greater wax worm, Galleria melonella have been found capable of hydrolyzing polyethylene (PE) (Yang et al., 2014; Bombelli et al., 2017; Cassone et al., 2020). Crit. 185, 163168. Nikolic, V., Sava, V., Dusan, A., and Aleksander, P. (2013). A review of plastic waste biodegradation. PS materials used in these studies range from pure PS or modified PS to PS blended with other polymers. Yang et al. doi: 10.1016/S0141-3910(98)00212-2, Zuchowska, D., Steller, R., and Meissner, W. (1998). 38, 863869. Photo-degradation is a process whereby the polymer chains in the product break down due to exposure to UV radiation. H. E.-D. Saleh, London: InTech. An overview of degradable and biodegradable polyolefins. Degrad. Sameh, A. S., Alariqi, Pradeep Kumar, A., Rao, B. S. M., and Singh, R. P. (2006). doi: 10.1007/s00253-011-3402-4, Barnes, D. K. A., Galgani, F., Thompson, R. C., and Barlaz, M. (2009). Stab. Synergistic effect of photo and chemical treatment on the rate of biodegradation of low density polyethylene by Fusarium sp. As a result of their massive accumulation in municipal waste systems, micro- and nano-sized plastic particles are now ubiquitous in both terrestrial and aquatic ecosystems (lvarez-Hernndez et al., 2019; Bergmann et al., 2019). doi: 10.1016/0964-8305(93)90002-J, Ali, M. I., Ahmed, S., Javed, I., Ali, N., Atiq, N., Hameed, A., et al. Currently, several organic UV stabilizers with different maximum absorption bonds are produced commercially. Biodegrad. strain NyZ450 and Bacillus sp. Technol. Int. The lignin degrading system includes a group of peroxidases known as Ligninases, which catalyze the initial oxidative depolymerization of lignin polymers (Bumpus and Aust, 1987; Bumpus et al., 1988; Shah et al., 1992). Polyhydroxyalkanoates (PHAs) have emerged as a sustainable choice due to their putative high biodegradability in different environments, biocompatibility, chemical diversity, their manufacture from renewable carbon resources, and release of non-polluting and non-toxic products after degradation (Bhatia et al., 2019a, b). doi: 10.1128/mBio.00570-17, Wei, R., Oeser, T., Barth, M., Weigl, N., Lbs, A., Schulz-Siegmund, M., et al. the Polymer Selector including but not limited to material suitability, material Cutinases have also been reported to hydrolyse aliphatic polyesters e.g., PCL (Kleeberg et al., 2005; Baker et al., 2012) as well as aliphatic aromatic co-polyesters such as PET (Herrero Acero et al., 2011; Ribitsch et al., 2012a; Roth et al., 2014; Wei et al., 2014b; Gamerith et al., 2017) and polytrimethylene terephthalate (PTT) (Eberl et al., 2009). 26, 246265. Poll. FEBS J. (1998). The leather treated with the FPU waterproong agent was placed under a 365 nm UV lamp with a power of 30 W, which was located 0.14 m from the light source. Microbiol. 3:e1700782. Microbial degradation of untreated PE has been reported in few others such as Pseudomonas putida IRN22, Acinetobacter pittii IRN19, Micrococcus luteus IRN20 (Montazer et al., 2019) and different species of Pseudomonas, Pseudomonas aeruginosa PAO1, P. aeruginosa ATCC, P. putida, and Pseudomonas syringae (Kyaw et al., 2012), Pseudomonas sp. Biodegrad. Degradation of polypropylene-poly L lactide blend by bacteria isolated from compost. doi: 10.1007/s00253-013-5489-2, Haernvall, K., Zitzenbacher, S., Wallig, K., Yamamoto, M., Schick, M. B., Ribitsch, D., et al. (2012a). Data and information contained in the Polymer Selector Rather, both the insect digestive system and the larval gut microbiome are required to achieve accelerated biodegradation of the PE polymers. Bull. Technol. J. Bacterial degradation of polyester polyurethane. Trans. J. Polym. doi: 10.1111/j.1462-2920.2009.01948.x, Ronqvist, M., Xie, W., Lu, W., and Gross, R. A. Figure 5. Owen, J. 6:52. doi: 10.1007/s13205-016-0394-x, Gamerith, C., Herrero Acero, E., Pellis, A., Ortner, A., Vielnascher, R., Luschnig, D., et al. Prog. 37, 44944499. Protein engineering studies on cutinases (Silva et al., 2011; Herrero Acero et al., 2013) and fusion to binding domains (Zhang et al., 2010; Ribitsch et al., 2013, 2015) have demonstrated enhanced polymer degradation. Early microbial biodegradation experiments attempted to demonstrate that microbial activity could result in changes in the physical characteristics of plastics, such as tensile strength, crystallinity, and water uptake (Pirt, 1980; Albertsson and Karlsson, 1990). Rep. 9:2612. doi: 10.1038/s41598-019-39366-0, Kataoka, M., Sasaki, M., Hidalgo, A. R., Nakano, M., and Shimizu, S. (2001). Ethylene glycol metabolism by Pseudomonas putida. Microbiol. Polym. Microbiol. doi: 10.1128/AEM.02773-17, Das, G., Bordoloi, N. K., Rai, S. K., Mukherjee, A. K., and Karak, N. (2012). There are many different types of esterase, which differ in their protein structure, substrate specificity, and biological functions. Biodegradation of Polycaprolactone (PCL) blended PP has also been demonstrated using lipase since lipase is well known to degrade the ester linkages of PCL (Weiland et al., 1995). Microbiol. doi: 10.17706/ijbbb.2017.7.4.245-251. J. Biosci. Degrad. Glyoxylate can be further metabolized by the Glyoxylate carboligase B (GclB) enzyme or AceA enzyme involved in the glyoxylate shunt (Blank et al., 2008) yielding two molecules of CO2 and two reducing equivalents. 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