Artículos de revistas: "Lipase"

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Sun, Jingjing, Yiling Chen, Jun Sheng y Mi Sun. "Immobilization ofYarrowia lipolyticaLipase on Macroporous Resin Using Different Methods: Characterization of the Biocatalysts in Hydrolysis Reaction". BioMed Research International 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/139179.

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To improve the reusability and organic solvent tolerance of microbial lipase and expand the application of lipase (hydrolysis, esterification, and transesterification), we immobilized marine microbial lipase using different methods and determined the properties of immobilized lipases. Considering the activity and cost of immobilized lipase, the concentration of lipase was fixed at 2 mg/mL. The optimal temperature of immobilized lipases was 40°C and 5°C higher than free lipase. The activities of immobilized lipases were much higher than free lipase at alkaline pH (more than 50% at pH 12). The free lipase lost most activity (35.3%) and immobilized lipases retained more than 46.4% of their initial activity after 3 h heat treatment at 70°C. At alkaline pH, immobilized lipases were more stable than free lipase (more than 60% residue activity at pH 11 for 3 h). Immobilized lipases retained 80% of their activity after 5 cycles and increased enzyme activity (more than 108.7%) after 3 h treatment in tert-butanol. Immobilization of lipase which improved reusability of lipase and provided a chance to expand the application of marine microbial lipase in organic system expanded the application range of lipase to catalyze hydrolysis and esterification in harsh condition.

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Bracco, Paula, Nelleke van Midden, Epifanía Arango, Guzman Torrelo, Valerio Ferrario, Lucia Gardossi y Ulf Hanefeld. "Bacillus subtilis Lipase A—Lipase or Esterase?" Catalysts 10, n.º 3 (7 de marzo de 2020): 308. http://dx.doi.org/10.3390/catal10030308.

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The question of how to distinguish between lipases and esterases is about as old as the definition of the subclassification is. Many different criteria have been proposed to this end, all indicative but not decisive. Here, the activity of lipases in dry organic solvents as a criterion is probed on a minimal α/β hydrolase fold enzyme, the Bacillus subtilis lipase A (BSLA), and compared to Candida antarctica lipase B (CALB), a proven lipase. Both hydrolases show activity in dry solvents and this proves BSLA to be a lipase. Overall, this demonstrates the value of this additional parameter to distinguish between lipases and esterases. Lipases tend to be active in dry organic solvents, while esterases are not active under these circumstances.

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Wang, Shang, Yan Xu y Xiao-Wei Yu. "Micro-Aqueous Organic System: A Neglected Model in Computational Lipase Design?" Biomolecules 11, n.º 6 (7 de junio de 2021): 848. http://dx.doi.org/10.3390/biom11060848.

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Water content is an important factor in lipase-catalyzed reactions in organic media but is frequently ignored in the study of lipases by molecular dynamics (MD) simulation. In this study, Candida antarctica lipase B, Candida rugosa lipase and Rhizopus chinensis lipase were used as research models to explore the mechanisms of lipase in micro-aqueous organic solvent (MAOS) media. MD simulations indicated that lipases in MAOS systems showed unique conformations distinguished from those seen in non-aqueous organic solvent systems. The position of water molecules aggregated on the protein surface in MAOS media is the major determinant of the unique conformations of lipases and particularly impacts the distribution of hydrophilic and hydrophobic amino acids on the lipase surface. Additionally, two maxima were observed in the water-lipase radial distribution function in MAOS systems, implying the formation of two water shells around lipase in these systems. The energy landscapes of lipases along solvent accessible areas of catalytic residues and the minimum energy path indicated the dynamic open states of lipases in MAOS systems differ from those in other solvent environments. This study confirmed the necessity of considering the influence of the microenvironment on MD simulations of lipase-catalyzed reactions in organic media.

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Guo, Chenchen, Rikuan Zheng, Ruining Cai, Chaomin Sun y Shimei Wu. "Characterization of Two Unique Cold-Active Lipases Derived from a Novel Deep-Sea Cold Seep Bacterium". Microorganisms 9, n.º 4 (10 de abril de 2021): 802. http://dx.doi.org/10.3390/microorganisms9040802.

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The deep ocean microbiota has unexplored potential to provide enzymes with unique characteristics. In order to obtain cold-active lipases, bacterial strains isolated from the sediment of the deep-sea cold seep were screened, and a novel strain gcc21 exhibited a high lipase catalytic activity, even at the low temperature of 4 °C. The strain gcc21 was identified and proposed to represent a new species of Pseudomonas according to its physiological, biochemical, and genomic characteristics; it was named Pseudomonas marinensis. Two novel encoding genes for cold-active lipases (Lipase 1 and Lipase 2) were identified in the genome of strain gcc21. Genes encoding Lipase 1 and Lipase 2 were respectively cloned and overexpressed in E. coli cells, and corresponding lipases were further purified and characterized. Both Lipase 1 and Lipase 2 showed an optimal catalytic temperature at 4 °C, which is much lower than those of most reported cold-active lipases, but the activity and stability of Lipase 2 were much higher than those of Lipase 1 under different tested pHs and temperatures. In addition, Lipase 2 was more stable than Lipase 1 when treated with different metal ions, detergents, potential inhibitors, and organic solvents. In a combination of mutation and activity assays, catalytic triads of Ser, Asp, and His in Lipase 1 and Lipase 2 were demonstrated to be essential for maintaining enzyme activity. Phylogenetic analysis showed that both Lipase 1 and Lipase 2 belonged to lipase family III. Overall, our results indicate that deep-sea cold seep is a rich source for novel bacterial species that produce potentially unique cold-active enzymes.

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Sholeha, Rofiqotus y Rudiana Agustini. "LIPASE BIJI-BIJIAN DAN KARAKTERISTIKNYA". Unesa Journal of Chemistry 10, n.º 2 (30 de mayo de 2021): 168–83. http://dx.doi.org/10.26740/ujc.v10n2.p168-183.

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Abstrak. Kebutuhan enzim sebagai biokatalis dalam bidang industri saat ini sangat tinggi. Jenis enzim yang bermacam-macam dan dari berbagai sumber telah banyak diteliti dan dikembangkan. Salah satu jenis enzim yang terus diteliti dan dikembangkan adalah lipase. Lipase adalah enzim golongan hidrolase yang mengkatalisis proses hidrolisis trigliserida menjadi gliserol dan asam lemak bebas.Lipase dapat ditemukan dalam berbagai sumber seperti pada mikroorganisme, hewan dan tumbuhan. Lipase banyak digunakan pada industri makanan, detergen, minyak, biodiesel dan farmasi. Artikel ini memaparkan beberapa aspek utama pada lipase yang berasal dari biji seperti reaksi-reaksi yang dikatalisis, karakteristik (suhu, pH, aktivator dan inhibitor), mekanisme katalisis oleh lipase serta contoh lipase biji yang telah diteliti karakteristiknya. Lipase ditemukan pada biji yang berkecambah yang berfungsi sebagai katalisator dalam proses mobilisasi lipid. Lipase memiliki kemampuan mengatalisis reaksi hidrolisis, esterifikasi, transesterifikasi, asidolisis, alkoholisis dan aminolisis dengan efisien dan stabil. Lipase dapat diklasifikasikan menjadi 3 golongan didasarkan pada kemampuannya dalam mensintesis ikatan ester yaitu lipase non spesifik, lipase spesifik 1,3 dan lipase spesifik asam lemak. Mekanisme katalisis oleh lipase melibatkan serangan nukleofilik pertama dari serin pada karbon karbonil ikatan ester menghasilkan enzim asil kovalen sebagai perantara dan melepaskan alkohol. Karakteristik biji-bijian yang telah diteliti karakteristik jenis lipase yang dihasilkan contohnya adalah African bean seed (Pentaclethra macrophylla Benth), Durian seed germination (Durio zibethinus L.), dan Biji karet (Hevea brasiliensis). Kata kunci : Lipase biji, karakteristik, mekanisme reaksi Abstract. The need for enzymes as biocatalysts in industry is currently very high. Various types of enzymes and from various sources have been widely researched and developed. One type of enzyme that is being researched and developed is lipase. Lipase is a hydrolase group enzyme that catalyzes the hydrolysis of triglycerides into glycerol and free fatty acids. Lipases can be found in various sources such as in microorganisms, animals and plants. Lipase is widely used in the food, detergent, oil, biodiesel and pharmaceutical industries. This article describes some of the main aspects of lipase derived from seeds such as catalyzed reactions, characteristics (temperature, pH, activator and inhibitor), the mechanism of catalysis by lipases and examples of seed lipases that have been investigated for their characteristics. Lipase is found in germinated seeds which functions as a catalyst in the lipid mobilization process. Lipase has the ability to catalyze hydrolysis, esterification, transesterification, acidolysis, alcoholysis and aminolysis reactions efficiently and stably. Lipases can be classified into 3 groups based on their ability to synthesize ester bonds, namely non-specific lipases, 1,3-specific lipases and fatty acid-specific lipases. The mechanism of catalysis by lipase involves the first nucleophilic attack of serine on the ester-bond carbonyl carbon producing covalent acyl enzymes as intermediates and releasing the alcohol. The characteristics of the grains that have been studied are the characteristics of the type of lipase produced, for example, African bean seeds (Pentaclethra macrophylla Benth), Durian seed germination (Durio zibethinus L.), and rubber seeds (Hevea brasiliensis). Keywords : Seed lipase, characteristics, reaction mechanism

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Prasasty, Vivitri Dewi, Vinella Winata y Muhammad Hanafi. "Identification and Characterization of Bacterial Lipase from Plateu Soil in West Java". Jurnal Kimia Terapan Indonesia 18, n.º 02 (3 de enero de 2017): 103–8. http://dx.doi.org/10.14203/jkti.v18i02.85.

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Lipases are known as glycerol ester hydrolases that catalyze the hydrolysis of triglycerides into free fatty acids and glycerol. Lipases are found in human, animal, plant, and microorganisms. The aim of this research is to identify lipase producers and characterize bacterial lipase from West Java plateau soil. Plateau soil bacteria samples were isolated on lipase screening medium containing Rhodamine B. Olive oil was used as a substrate in screening and production medium bacterial lipases. From 16 bacterial isolate of lipase producers, 14 were identified as Bacillus sp. and the others were identified as Pseudomonas alcaligenes. All isolates were taken into production step to determine their lipase activities. Moreover, top 3 lipase activities out of 16 lipase activities were chosen to find the optimum pH and temperature. Both characterizations showed pH optimum and temperature optimum from each lipase. These optimum condition were used in heat stability characterization for each lipase samples. The result showed that lipase from isolate COK 2 in optimum pH 4 and temperature 50oC was the most stable lipase due to this sample has good and stable activity for 1 to 5 hours incubation time. Lipase sample from isolate COK 2 has good efficiency for lipase productivity in acid condition and high temperature. Results of this investigation could encourage utilization of these activity enhancers for various industrial applications.

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Lestari, Puji, Santi Nur Handayani y Oedjijono Oedjijono. "SIFAT-SIFAT BIOKIMIAWI EKSTRAK KASAR LIPASE EKSTRASELULER DARI BAKTERI Azospirillum sp. JG3". Molekul 4, n.º 2 (1 de noviembre de 2009): 73. http://dx.doi.org/10.20884/1.jm.2009.4.2.65.

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Lipases are valuable biocatalysts because they act under extremely mild conditions, are stable in organic solvents, show broad substrate specificity and exhibit high stereoselectivity. Lipases play important role in various industries such as detergent, cosmetics, flavor, pharmacy and synthesis of organic compounds. The increasing of lipases requirements in industries is goading research to get new lipases resources commited. One of potential lipase resource is Azospirillum sp.JG3 bacteria from Microbiology Laboratory of Biology Faculty University of Jenderal Soedirman. The specific targets of this research are to get crude extract of lipase and investigate its biochemical characteristics. The method used were rejuvenation of Azospirillum sp.JG3 bacteria, inoculum production, determination of optimum production time and bacterium growth phase, extraction and production of lipase to get crude extract, and characterization the biochemical properties of lipase crude extract. The research resulted that crude extract of lipase from Azospirillum sp.JG3 had optimum temperature at 40 °C and optimum pH at pH 7. The lipase was a metalloenzyme with Ca2+ as its cofactor. The lipase was stable in three organic solvents tested, (chloroform, n-hexane and ether).

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Köffel, René, Rashi Tiwari, Laurent Falquet y Roger Schneiter. "The Saccharomyces cerevisiae YLL012/YEH1, YLR020/YEH2, and TGL1 Genes Encode a Novel Family of Membrane-Anchored Lipases That Are Required for Steryl Ester Hydrolysis". Molecular and Cellular Biology 25, n.º 5 (1 de marzo de 2005): 1655–68. http://dx.doi.org/10.1128/mcb.25.5.1655-1668.2005.

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ABSTRACT Sterol homeostasis in eukaryotic cells relies on the reciprocal interconversion of free sterols and steryl esters. The formation of steryl esters is well characterized, but the mechanisms that control steryl ester mobilization upon cellular demand are less well understood. We have identified a family of three lipases of Saccharomyces cerevisiae that are required for efficient steryl ester mobilization. These lipases, encoded by YLL012/YEH1, YLR020/YEH2, and TGL1, are paralogues of the mammalian acid lipase family, which is composed of the lysosomal acid lipase, the gastric lipase, and four novel as yet uncharacterized human open reading frames. Lipase triple-mutant yeast cells are completely blocked in steryl ester hydrolysis but do not affect the mobilization of triacylglycerols, indicating that the three lipases are required for steryl ester mobilization in vivo. Lipase single mutants mobilize steryl esters to various degrees, indicating partial functional redundancy of the three gene products. Lipase double-mutant cells in which the third lipase is expressed from the inducible GAL1 promoter have greatly reduced steady-state levels of steryl esters, indicating that overexpression of any of the three lipases is sufficient for steryl ester mobilization in vivo. The three yeast enzymes constitute a novel class of membrane-anchored lipases that differ in topology and subcellular localization.

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Araiza-Villanueva, M. G., D. R. Olicón-Hernández, J. P. Pardo, H. Vázquez-Meza y G. Guerra-Sánchez. "Monitoring of the enzymatic activity of intracellular lipases of Ustilago maydis expressed during the growth under nitrogen limitation and its correlation in lipolytic reactions". Grasas y Aceites 70, n.º 4 (19 de julio de 2019): 327. http://dx.doi.org/10.3989/gya.1049182.

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Under nitrogen starvation, Ustilago maydis forms lipid droplets (LDs). Although the dynamics of these organelles are known in the literature, the identity of the lipases implicated in their degradation is unknown. We determined lipase activity and identified the intracellular lipases expressed during growth under nitrogen starvation and YPD media by zymograms. The results showed that cytosolic extracts exhibited higher lipase activity when cells were grown in YPD. Under nitrogen starvation, lipase activity was not detected after 24 h of culture, resulting in lipid accumulation in LDs. This suggests that these lipases could be implicated in LD degradation. In the zymogram, two bands, one of 25 and the other of 37 kDa, presented lipase activity. The YPD extracts showed lipase activity in olive and almond oils, which contain triacylglycerols with mono and polyunsaturated fatty acids. This is the first report about U. maydis cytosolic lipases involved in LD degradation.

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Palomo, Jose M., Claudia Ortiz, Manuel Fuentes, Gloria Fernandez-Lorente, Jose M. Guisan y Roberto Fernandez-Lafuente. "Use of immobilized lipases for lipase purification via specific lipase–lipase interactions". Journal of Chromatography A 1038, n.º 1-2 (junio de 2004): 267–73. http://dx.doi.org/10.1016/j.chroma.2004.03.058.

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Veloso, Elizabeth Cristina Tavares, Thamires Maciel de Lima Oliveira Da Silva, João Paulo da Silva Queiroz Menezes, Alexandre Barros Gaspar, Marcia Monteiro Machado Gonçalves, Gizele Cardoso Fontes-Sant’Ana y Marta Antunes Pereira Langone. "Activated carbon from sugarcane bagasse as support for lipase immobilization by physical adsorption technique". Cuadernos de Educación y Desarrollo 16, n.º 1 (10 de enero de 2024): 588–612. http://dx.doi.org/10.55905/cuadv16n1-032.

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Lipases are recognized as the most important group of catalysts in biotechnology. However, utilization of free enzymes is often hampered by the need for more operational stability, high cost, and non-reusability. Most of these obstacles can be solved by lipase immobilization. This work's objective was to evaluate the performance of the activated carbon obtained from sugarcane straw (SAC) as a support for lipase immobilization. Two lipases were immobilized by physical adsorption on SAC: Aspergillus niger 11T53A14 lipase and CalB (lipase B from Candida antarctica, Novozymes). Results revealed that the lipase had been anchored on the activated carbon with the lipase binding efficiency of 89 % (A. niger lipase) and 100 % (CalB) at the optimum experimental conditions (initial protein concentration 0.1 mg mL-1, 0.15 g of SAC, 25 °C, and 120 min). Langmuir isotherm fitted the adsorption equilibrium data of the lipases on SAC. SAC presents a high surface area and protein adsorption capacity. These results show that activated carbon synthesized from the sugarcane straw is a promising support for enzyme immobilization.

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Liu, Shao Quan, Huey Yie Lee, Bin Yu, Philip Curran y Jingcan Sun. "Bioproduction of Natural Isoamyl Esters from Coconut Cream as Catalysed by Lipases". Journal of Food Research 2, n.º 2 (29 de marzo de 2013): 157. http://dx.doi.org/10.5539/jfr.v2n2p157.

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This study investigated the bioproduction of isoamyl esters in coconut cream by lipases. Five lipases (palatase 20000 L, lipase AYS “Amano”, lipase A “Amano” 12, piccantase A and piccantase AN) were used to biosynthesize isoamyl esters in coconut cream supplemented with isoamyl alcohol. The lipases have different abilities to synthesize isoamyl esters with lipase AYS “Amano”, palatase 20000 L and piccantase A showing the highest potential. Bioproduction of isoamyl octanoate by palatase 20000 L was further examined under different conditions of temperature, pH, isoamyl alcohol concentration and lipase amount. Biosynthesis of isoamyl octanoate by palatase was not significantly affected at 30-50°C or pH of 4 to 7 and its maximum bioproduction was obtained at isoamyl alcohol concentration of 4% (v/v) and lipase amount of 6 mg 100 mL-1 reaction mixture. The lipase-treated coconut cream may serve as a bioflavouring ingredient for food applications or for extraction of pure aroma chemicals.

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Wei, Xianqin, Jiaxing Li, Tao Wang, Jinhua Xiao y Dawei Huang. "Genome-Wide Identification and Analysis of Lipases in Fig Wasps (Chalcidoidea, Hymenoptera)". Insects 13, n.º 5 (24 de abril de 2022): 407. http://dx.doi.org/10.3390/insects13050407.

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Lipases are the main enzymes involved in lipid metabolism. However, the characteristics of lipases in insects were scarcely investigated. Here, we screened the recently sequenced genomes of 12 fig wasp species consisting of seven pollinator fig wasps (PFWs) and five non-pollinating fig wasps (NPFWs) for the six major lipase gene families. In total, 481 lipase genes were identified, and the two most numerous families were the neutral and acid lipases. Tandem duplication accounted for the expansion of the gene family. NPFWs had significantly more lipases than PFWs. A significant gene family contraction occurred in the clade of PFWs. The difference of lipases between NPFWs and PFWs might contribute to their distinction in life histories and feeding regimes. Phylogenetic analysis showed that the lipase genes of each fig wasp species was almost equally distributed in each clade, indicating that the lipase genes were conserved. The gene structures were similar within each clade, while they were different among clades. Most of the neutral and acid lipases were signal peptides and located extracellularly. The pathways of lipases involved were predicted. This genome-wide study provides a systematic analysis of lipase gene families in 12 hymenopteran insects and further insights towards understanding the potential functions of lipases.

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Bodhak, Dorothy y Priya Sundarrajan. "Characterization of lipase from lipase-producing bacteria and its application in the reduction of triglyceride content in milk sample". Research Journal of Biotechnology 17, n.º 11 (25 de octubre de 2022): 118–26. http://dx.doi.org/10.25303/1711rjbt1180126.

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Lipases hydrolyse esters of long-chain fatty acids. They have several biotechnological applications such as in the field of food technology, leather, cosmetics, detergents, textiles, oleochemicals, pharmaceuticals and industrial waste. Lipases occur widely in nature in animals, plants and microorganisms; however, in terms of commercial significance, microbial lipases are the most beneficial owing to the ease of production. This study aimed to characterise lipase isolated from lipase-producing bacteria, which were screened on Tributyrin agar to confirm lipase production. Growth parameters of the isolates including their temperature and pH tolerance were determined so that they can be applied for potential industrial uses. The enzymatic activity, pH optimum and temperature optimum of the lipase were determined by the p-nitro phenyl palmitate assay. Finally, the lipase was used to reduce triglyceride content in full-fat buffalo milk.

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Stathopoulou, Panagiota M., Alexander L. Savvides, Amalia D. Karagouni y Dimitris G. Hatzinikolaou. "Unraveling the Lipolytic Activity of Thermophilic Bacteria Isolated from a Volcanic Environment". BioMed Research International 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/703130.

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In a bioprospecting effort towards novel thermostable lipases, we assessed the lipolytic profile of 101 bacterial strains isolated from the volcanic area of Santorini, Aegean Sea, Greece. Screening of lipase activity was performed both in agar plates and liquid cultures using olive oil as carbon source. Significant differences were observed between the two screening methods with no clear correlation between them. While the percentage of lipase producing strains identified in agar plates was only 17%, lipolytic activity in liquid culture supernatants was detected for 74% of them. Nine strains exhibiting elevated extracellular lipase activities were selected for lipase production and biochemical characterization. The majority of lipase producers revealed high phylogenetic similarity withGeobacillusspecies and related genera, whilst one of them was identified asAneurinibacillussp. Lipase biosynthesis strongly depended on the carbon source that supplemented the culture medium. Olive oil induced lipase production in all strains, but maximum enzyme yields for some of the strains were also obtained with Tween-80, mineral oil, and glycerol. Partially purified lipases revealed optimal activity at 70–80°C and pH 8-9. Extensive thermal stability studies revealed marked thermostability for the majority of the lipases as well as a two-step thermal deactivation pattern.

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Knezevic, Zorica, Slavica Siler-Marinkovic y Ljiljana Mojovic. "Immobilized lipases as practical catalysts". Acta Periodica Technologica, n.º 35 (2004): 151–64. http://dx.doi.org/10.2298/apt0435151k.

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Attractive features of lipase systems include versatility, substrate selectivity, regioselectivity, enantioselectivity and catalysis at ambient temperatures and pressures. To fully exploit the technical and economical advantages of lipases, it is recommended to use them in an immobilized form to reduce the cost and the poor stability of the free lipase. This paper summarizes various methods of lipases immobilization including covalent attachment to or adsorption on solid supports, encapsulation and entrapment within the membrane and in polymeric matrices. The effects of immobilization conditions on lipase properties and stability of biocatalysts are considered. Applications of immobilized lipases in the feasible reaction system as well as probable future trends in lipase catalyzed process are discussed.

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Mala, John Geraldine Sandana y Satoru Takeuchi. "Understanding Structural Features of Microbial Lipases–-An Overview". Analytical Chemistry Insights 3 (enero de 2008): ACI.S551. http://dx.doi.org/10.4137/aci.s551.

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The structural elucidations of microbial lipases have been of prime interest since the 1980s. Knowledge of structural features plays an important role in designing and engineering lipases for specific purposes. Significant structural data have been presented for few microbial lipases, while, there is still a structure-deficit, that is, most lipase structures are yet to be resolved. A search for ‘lipase structure’ in the RCSB Protein Data Bank ( http://www.rcsb.org/pdb/ ) returns only 93 hits (as of September 2007) and, the NCBI database ( http://www.ncbi.nlm.nih.gov ) reports 89 lipase structures as compared to 14719 core nucleotide records. It is therefore worthwhile to consider investigations on the structural analysis of microbial lipases. This review is intended to provide a collection of resources on the instrumental, chemical and bioinformatics approaches for structure analyses. X-ray crystallography is a versatile tool for the structural biochemists and is been exploited till today. The chemical methods of recent interests include molecular modeling and combinatorial designs. Bioinformatics has surged striking interests in protein structural analysis with the advent of innumerable tools. Furthermore, a literature platform of the structural elucidations so far investigated has been presented with detailed descriptions as applicable to microbial lipases. A case study of Candida rugosa lipase (CRL) has also been discussed which highlights important structural features also common to most lipases. A general profile of lipase has been vividly described with an overview of lipase research reviewed in the past.

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Faradis, Taritsu Hazal, Meilynda Pomeistia, Nurul Hasan Basri, Jannatin 'Ardhuha, Erin Ryantin Gunawan y Lalu Rudyat Telly Savalas. "Biochemical Characterization of Ketapang Lipase: Its Preference to Short-Chain Fatty Acids despite the Long-Chain Fatty Acids Dominant Content". Molekul 18, n.º 2 (10 de julio de 2023): 321. http://dx.doi.org/10.20884/1.jm.2023.18.2.8302.

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Lipases are versatile enzymes with high specificity toward lipid substrate. They have many industrial applications, such as in food, pharmacy, and green fuel. So far, most explored lipases are from microbial and animal sources, whereas those from plants are less studied. The present study aims to characterize ketapang (Terminalia catappa Linn) lipase. The lipase was isolated from germinating ketapang seeds. The activity was determined by hydrolysis of virgin coconut oil (VCO). Biochemical characterization of ketapang lipase includes the optimum temperature, pH, kinetics, metal ions addition, and analysis of substrate specificity. It was shown that ketapang lipase has an optimum temperature of 45 oC, pH 7.5. Ca2+ increases the lipase activity, whereas Na+, K+, Mg2+, Zn2+, Fe2+, and Cu2+ inhibit ketapang lipase to various extents. A comparison of SDS-PAGE and native-PAGE analysis showed that ketapang lipase consists of several protein subunits. A further test by in-gel assay revealed that the 54 kDa, 35 kDa, two bands at ~16 kDa, and 12 kDa proteins showed lipolytic activity against a-naphthyl palmitate substrate. When tested on various chromogenic fatty acid substrates, ketapang lipase showed the highest specificity against short-chain fatty acids (C4 and C8), despite the fact that ketapang oil seed composes mainly of long fatty acid (C18). Since lipases that have high lipolytic activity toward short fatty acids are considered esterases, the esterase activity of ketapang lipase is yet to be determined.

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Jacobsen, Tomas y Otto M. Poulsen. "Separation and characterization of 61- and 57-kDa lipases from Geotrichum candidum ATCC 66592". Canadian Journal of Microbiology 38, n.º 1 (1 de enero de 1992): 75–80. http://dx.doi.org/10.1139/m92-012.

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Two lipolytic proteins (61 and 57 kDa) present in a Sephadex G-100 fraction of extracellular lipase from Geotrichum candidum ATCC 66592 were separated using high-performance liquid chromatography. Crossed electrofocusing immunoelectrophoresis was used to demonstrate that the 61-kDa lipase fraction contained two forms of lipase with pI 4.5 and 4.7. However, when deglycosylated with endoglycosidase H, the two forms gained an identical pI, 4.6. The 57-kDa lipase fraction contained one form of lipase with pI close to 4.5. Although the 61- and 57-kDa lipases were immunologically identical, the substrate specificity differed. Thus, the 61-kDa lipase hydrolysed palmitic acid methyl ester at an initial velocity of hydrolysis that was 60% of the initial velocity of hydrolysis of oleic acid methyl ester, whereas the 57-kDa lipase hydrolysed palmitic acid methyl ester at an initial velocity of hydrolysis that was only7% of the initial velocity of hydrolysis of oleic acid methyl ester. Key words: Geotrichum candidum, lipases, multiple forms, deglycosylation, substrate specificity.

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Abdul Rahman, Mohd Basyaruddin, Mahiran Basri, Mohd Zobir Hussein, Raja Nor Zaliha Raja Abdul Rahman, Yau Kim Yan y Abu Bakar Salleh. "Activated Carbon as Support for Lipase Immobilization". Eurasian Chemico-Technological Journal 5, n.º 2 (5 de abril de 2007): 115. http://dx.doi.org/10.18321/ectj298.

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Lipase from Candida rugosa was immobilized onto four different types of activated carbon; KI/2030, KI/3040, KI/5060 and KI/6070. The immobilized lipase was used in the esterification of oleic acid and 1-butanol in hexane. The effects of difference pore sizes, surface area, reaction temperature, thermostability of the immobilized lipases, storage stability in organic solvent and leaching studies were investigated. Among the four samples, KI/6070 gave the highest activities and stability in all the parameters investigated. Immobilized lipases generally exhibit activities higher than the native lipase for the parameters studied, with optimum temperature of 40°C. Immobilized lipases are more stable than native lipase in hexane at room temperature up to 12 days. Leaching study proved that the immobilization of lipase using physical adsorption is cheap and easy. This method was found to be suitable for the attachment of enzyme on the support.

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Valek, Tomas, Adam Kostelnik, Pavla Valkova y Miroslav Pohanka. "Indoxyl Acetate as a Substrate for Analysis of Lipase Activity". International Journal of Analytical Chemistry 2019 (1 de diciembre de 2019): 1–7. http://dx.doi.org/10.1155/2019/8538340.

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Lipases play a crucial role in metabolism of microbes, fungi, plants, and animals, and in analytical chemistry, they are often used in detection of fats and triglycerides. Determination of lipase activity is also important in toxicology, when lipase activity can be both increased and decreased by organophosphates and other pesticides and in medicine for diagnosis of heart diseases. The standard method for lipase activity determination is based on cleaving ester bonds in lipase buffer containing Tween. Our aim was to find a method with faster and more sensitive response. It is known that acetylcholinesterase belongs to the same group of hydrolases enzymes as lipases and it cleaves indoxyl acetate, so we assume indoxyl acetate could report a similar reaction with lipase. Our method is based on indoxyl acetate as a substrate for lipase, where indoxyl acetate is cleaved by lipase to indoxyl and acetate moiety and blue indigo is created. The method was optimized for different times and amount of enzyme and compared with the standard Tween assay. The calibration curve measured in reaction time 20 minutes with 10 μl of lipase exhibited the best analytical parameters, and it showed Michaelis–Menten response with the Michaelis–Menten constant equal to 8.72 mmol/l. The indoxyl acetate-based method showed faster and more sensitive response than the standard method for lipase activity determination, so it has great potential in biosensor construction and it could be used in industry, medicine, toxicology, and common practice where the activity of lipases is need to be measured.

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22

Høegh, Inge, Shamkant Patkar, Torben Halkier y Mogens T. Hansen. "Two lipases from Candida antarctica: cloning and expression in Aspergillus oryzae". Canadian Journal of Botany 73, S1 (31 de diciembre de 1995): 869–75. http://dx.doi.org/10.1139/b95-333.

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The basidiomycetous yeast Candida antarctica expresses two lipases that possess widely different properties. The genes LIPA and LIPB encoding both lipases were cloned and sequenced. Both lipases were secreted efficiently from Aspergillus oryzae transformed with lipase expression plasmids. N-Glycosylation was slightly more extensive in the heterologously expressed enzymes than in those purified from C. antarctica, but the enzymatic characteristics were retained. Both enzymes are encoded as preproenzymes. Proteolytic processing of the primary translation product was efficient in A. oryzae and resulted in the same N-terminals as in C. antarctica. Modifications or deletions of the propeptide of lipase component B did not prevent efficient secretion of active lipase from A. oryzae. Alternative proteolytic processing of the modified propeptides was detected. Key words: Lipase, Candida, cloning, Aspergillus, expression, propeptide.

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23

Stamenkovic, Olivera, Miodrag Lazic, Vlada Veljkovic y Dejan Skala. "Biodiesel production by enzyme-catalyzed transesterification". Chemical Industry 59, n.º 3-4 (2005): 49–59. http://dx.doi.org/10.2298/hemind0504049s.

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The principles and kinetics of biodiesel production from vegetable oils using lipase-catalyzed transesterification are reviewed. The most important operating factors affecting the reaction and the yield of alkyl esters, such as: the type and form of lipase, the type of alcohol, the presence of organic solvents, the content of water in the oil, temperature and the presence of glycerol are discussed. In order to estimate the prospects of lipase-catalyzed transesterification for industrial application, the factors which influence the kinetics of chemically-catalysed transesterification are also considered. The advantages of lipase-catalyzed transesterification compared to the chemically-catalysed reaction, are pointed out. The cost of down-processing and ecological problems are significantly reduced by applying lipases. It was also emphasized that lipase-catalysed transesterification should be greatly improved in order to make it commercially applicable. The further optimization of lipase-catalyzed transesterification should include studies on the development of new reactor systems with immobilized biocatalysts and the addition of alcohol in several portions, and the use of extra cellular lipases tolerant to organic solvents, intracellular lipases (i.e. whole microbial cells) and genetically-modified microorganisms ("intelligent" yeasts).

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24

Cygler, Miroslaw, Pawel Grochulski y Joseph D. Schrag. "Structural determinants defining common stereoselectivity of lipases toward secondary alcohols". Canadian Journal of Microbiology 41, n.º 13 (15 de diciembre de 1995): 289–96. http://dx.doi.org/10.1139/m95-199.

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In this review we summarize some aspects of the enantiopreference of the lipase from Candida rugosa following structural analysis of complexes of this lipase with two enantiomers of an analog of a tetrahedral intermediate in the hydrolysis of simple esters. The analysis of the molecular basis of the enantiomeric differentiation suggests that these results can be generalized to a large class of lipases and esterases. We also summarize our experiments on identification of the key regions in the lipases from Geotrichum candidum lipase responsible for differentiation between fatty acyl chains.Key words: lipases, stereoselectivity, three-dimensional structure, conformational rearrangement.

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25

Albayati, Samah Hashim, Malihe Masomian, Siti Nor Hasmah Ishak, Mohd Shukuri bin Mohamad Ali, Adam Leow Thean, Fairolniza binti Mohd Shariff, Noor Dina binti Muhd Noor y Raja Noor Zaliha Raja Abd Rahman. "Main Structural Targets for Engineering Lipase Substrate Specificity". Catalysts 10, n.º 7 (6 de julio de 2020): 747. http://dx.doi.org/10.3390/catal10070747.

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Microbial lipases represent one of the most important groups of biotechnological biocatalysts. However, the high-level production of lipases requires an understanding of the molecular mechanisms of gene expression, folding, and secretion processes. Stable, selective, and productive lipase is essential for modern chemical industries, as most lipases cannot work in different process conditions. However, the screening and isolation of a new lipase with desired and specific properties would be time consuming, and costly, so researchers typically modify an available lipase with a certain potential for minimizing cost. Improving enzyme properties is associated with altering the enzymatic structure by changing one or several amino acids in the protein sequence. This review detailed the main sources, classification, structural properties, and mutagenic approaches, such as rational design (site direct mutagenesis, iterative saturation mutagenesis) and direct evolution (error prone PCR, DNA shuffling), for achieving modification goals. Here, both techniques were reviewed, with different results for lipase engineering, with a particular focus on improving or changing lipase specificity. Changing the amino acid sequences of the binding pocket or lid region of the lipase led to remarkable enzyme substrate specificity and enantioselectivity improvement. Site-directed mutagenesis is one of the appropriate methods to alter the enzyme sequence, as compared to random mutagenesis, such as error-prone PCR. This contribution has summarized and evaluated several experimental studies on modifying the substrate specificity of lipases.

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26

Fernandez-Lopez, Laura, Sergi Roda, Ana Robles-Martín, Rubén Muñoz-Tafalla, David Almendral, Manuel Ferrer y Víctor Guallar. "Enhancing the Hydrolytic Activity of a Lipase towards Larger Triglycerides through Lid Domain Engineering". International Journal of Molecular Sciences 24, n.º 18 (6 de septiembre de 2023): 13768. http://dx.doi.org/10.3390/ijms241813768.

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Lipases have valuable potential for industrial use, particularly those mostly active against water-insoluble substrates, such as triglycerides composed of long-carbon chain fatty acids. However, in most cases, engineered variants often need to be constructed to achieve optimal performance for such substrates. Protein engineering techniques have been reported as strategies for improving lipase characteristics by introducing specific mutations in the cap domain of esterases or in the lid domain of lipases or through lid domain swapping. Here, we improved the lipase activity of a lipase (WP_075743487.1, or LipMRD) retrieved from the Marine Metagenomics MarRef Database and assigned to the Actinoalloteichus genus. The improvement was achieved through site-directed mutagenesis and by substituting its lid domain (FRGTEITQIKDWLTDA) with that of Rhizopus delemar lipase (previously R. oryzae; UniProt accession number, I1BGQ3) (FRGTNSFRSAITDIVF). The results demonstrated that the redesigned mutants gain activity against bulkier triglycerides, such as glyceryl tridecanoate and tridodecanoate, olive oil, coconut oil, and palm oil. Residue W89 (LipMRD numbering) appears to be key to the increase in lipase activity, an increase that was also achieved with lid swapping. This study reinforces the importance of the lid domains and their amino acid compositions in determining the substrate specificity of lipases, but the generalization of the lid domain swapping between lipases or the introduction of specific mutations in the lid domain to improve lipase activity may require further investigation.

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27

Bassegoda, Arnau, F. I. Javier Pastor y Pilar Diaz. "Rhodococcus sp. Strain CR-53 LipR, the First Member of a New Bacterial Lipase Family (Family X) Displaying an Unusual Y-Type Oxyanion Hole, Similar to the Candida antarctica Lipase Clan". Applied and Environmental Microbiology 78, n.º 6 (6 de enero de 2012): 1724–32. http://dx.doi.org/10.1128/aem.06332-11.

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ABSTRACTBacterial lipases constitute the most important group of biocatalysts for synthetic organic chemistry. Accordingly, there is substantial interest in developing new valuable lipases. Considering the lack of information concerning the lipases of the genusRhodococcusand taking into account the interest raised by the enzymes produced by actinomycetes, a search for putative lipase-encoding genes fromRhodococcussp. strain CR-53 was performed. We isolated, cloned, purified, and characterized LipR, the first lipase described from the genusRhodococcus. LipR is a mesophilic enzyme showing preference for medium-chain-length acyl groups without showing interfacial activation. It displays good long-term stability and high tolerance for the presence of ions and chemical agents in the reaction mixture. Amino acid sequence analysis of LipR revealed that it displays four unique amino acid sequence motifs that clearly separate it from any other previously described family of bacterial lipases. Using bioinformatics tools, LipR could be related only to several uncharacterized putative lipases from different bacterial origins, all of which display the four blocks of consensus amino acid sequence motifs that contribute to define a new family of bacterial lipases, namely, family X. Therefore, LipR is the first characterized member of the new bacterial lipase family X. Further confirmation of this new family of lipases was performed after cloningBurkholderia cenocepaciaputative lipase, bearing the same conserved motifs and clustering in family X. Interestingly, all lipases grouping in the new bacterial lipase family X display a Y-type oxyanion hole, a motif conserved in theCandida antarcticalipase clan but never found among bacterial lipases. This observation contributes to confirm that LipR and its homologs belong to a new family of bacterial lipases.

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Cheng, Wenjun y Binbin Nian. "Computer-Aided Lipase Engineering for Improving Their Stability and Activity in the Food Industry: State of the Art". Molecules 28, n.º 15 (3 de agosto de 2023): 5848. http://dx.doi.org/10.3390/molecules28155848.

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As some of the most widely used biocatalysts, lipases have exhibited extreme advantages in many processes, such as esterification, amidation, and transesterification reactions, which causes them to be widely used in food industrial production. However, natural lipases have drawbacks in terms of organic solvent resistance, thermostability, selectivity, etc., which limits some of their applications in the field of foods. In this systematic review, the application of lipases in various food processes was summarized. Moreover, the general structure of lipases is discussed in-depth, and the engineering strategies that can be used in lipase engineering are also summarized. The protocols of some classical methods are compared and discussed, which can provide some information about how to choose methods of lipase engineering. Thermostability engineering and solvent tolerance engineering are highlighted in this review, and the basic principles for improving thermostability and solvent tolerance are summarized. In the future, comput er-aided technology should be more emphasized in the investigation of the mechanisms of reactions catalyzed by lipases and guide the engineering of lipases. The engineering of lipase tunnels to improve the diffusion of substrates is also a promising prospect for further enhanced lipase activity and selectivity.

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29

Ahmad, Sana, Aliya Riaz, Hina Abbasi, Reeja Eijaz y Muhammad Noman Syed. "Modification of Process Parameters for Enhanced Lipase Induction from Bacillus SR1". RADS Journal of Biological Research & Applied Sciences 10, n.º 1 (16 de julio de 2019): 14–17. http://dx.doi.org/10.37962/jbas.v10i1.137.

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The enzymes catalyze the cleavage of triacylglycerols into fatty acids and glycerols are referred to as lipases (EC 3.1.1.3). Lipases are widely distributed in flora and fauna. Microbial lipases are of great importance than lipases from plants and animals due to their catalytic activity, ease of production and optimization. Lipases have tremendous industrial applications such as in the processing of fats and oils, detergents and degreasing formulations, food processing, the synthesis of fine chemicals, paper manufacture, and production of cosmetics, and pharmaceuticals. Therefore, a potential lipase producing bacterial strain was isolated and identified as gram +ve Bacillus SR1. Among different oils tested, olive oil was found to be the favorable substrate for lipase induction. Additionally, lipase induction was observed highest in 24 hours of fermentation at 37⁰C and pH 7.5.

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30

RN, Patel, A. Banerjee, Ko RY, Howell JM, Li WS, Comezoglu FT, Partyka RA y Szarka FT. "Enzymic preparation of (3R‐cis)‐3‐(acetyloxy)‐4‐phenyl‐2‐azetidinone: a taxol side‐chain synthon". Biotechnology and Applied Biochemistry 20, n.º 1 (agosto de 1994): 23–33. http://dx.doi.org/10.1111/j.1470-8744.1994.tb00304.x.

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A key chiral intermediate [(3R‐cis)‐3‐(acetyloxy)‐4‐phenyl‐2‐azetidinone (2)] for the semi‐synthesis of paclitaxel (taxol; 5), an anti‐cancer compound, was prepared by an enzymic process. The stereoselective enzymic hydrolysis of cis‐3‐(acetyloxy)‐4‐phenyl‐2‐azetidinone (1) to the corresponding (S)‐(‐)‐alcohol (3) was carried out using various lipases. Lipase PS‐30 (Pseudomonas cepacia) and BMS (Bristol‐Myers Squibb) lipase (Pseudomonas sp. SC13856) catalysed hydrolysis of the undesired enantiomer of racemic compound 1, producing the (S)‐(‐)‐alcohol (3) and the desired (R)‐(+)‐acetate (2). Reaction yields of > 96% and optical purities of > 99.5% were obtained. For a very efficient enzyme source (BMS lipase), a lipase fermentation using Pseudomonas sp. SC13856 was developed. In a fed‐batch process using soybean oil, the fermentation resulted in 1500 units of extracellular lipase activity/ml. Crude BMS lipase (1.7 kg, containing 140,000 units/g) was recovered from the filtrate by ethanol precipitation. BMS lipase and commercially available lipase PS‐30 were independently immobilized on Accurel polypropylene. These immobilized lipases were re‐used (ten cycles) without loss of enzyme activity, productivity or optical purity of the product. The enzymic reaction process was scaled up to 75 and 150 litres using immobilized BMS lipase and lipase PS‐30 respectively. From the reaction mixture, compound 2 was isolated in 88‐90 mol% yield and 99.5% optical purity. A purity of 99.9 (area %) was demonstrated by g.c. for isolated compound 2.

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Berdiev, Nodir Sh, Jamolitdin F. Ziyavitdinov, Akmal M. Asrorov, Shukhratjon S. Olimjonov y Shavkat I. Salikhov. "Characterization of a novel lipase from Pseudomonas aeruginosa". Nova Biotechnologica et Chimica 18, n.º 1 (1 de junio de 2019): 44–51. http://dx.doi.org/10.2478/nbec-2019-0006.

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Abstract Lipases cleaving oils into fatty acids and glycerol are of great interest for the use in increasing the efficiency of fuels. In this work, a novel lipase from Pseudomonas aeruginosa, P. aeruginosa A12, was isolated by ion-exchange and hydrophobic chromatography. The purity of lipase was shown by electrophoresis and its molecular weight was estimated to be ~ 31.6 kDa. The whole amino acid sequence was analyzed by an LC-MS/MS method. Temperature- and pH-dependent optimum of the enzyme compiled 30 °C and 7.5, respectively. The obtained enzyme exhibited 79 % similarity of amino acid sequence to a lipase isolated from the same strain of P. aeruginosa. Thus, the novel lipase was determined to belong to I.1 subfamily of bacterial true lipases. Three dimensional structure of the isolated lipase isoform was modeled based on obtained sequences. Amino acids forming the catalytic domain were shown in the model. Lid domain is suggested to be in the open conformation. These results provide a potential alternative for enzymatic digestion of fuel oils and serve for the development of fundamental knowledge of lipase activity.

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32

Bravo-Ruiz, Gustavo, Carmen Ruiz-Roldán y M. Isabel G. Roncero. "Lipolytic System of the Tomato Pathogen Fusarium oxysporum f. sp. lycopersici". Molecular Plant-Microbe Interactions® 26, n.º 9 (septiembre de 2013): 1054–67. http://dx.doi.org/10.1094/mpmi-03-13-0082-r.

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The lipolytic profile of Fusarium oxysporum f. sp lycopersici was studied by in silico search and biochemical enzyme activity analyses. Twenty-five structural secreted lipases were predicted based on the conserved pentapeptide Gly-X-Ser-X-Gly-, characteristic of fungal lipases, and secretion signal sequences. Moreover, a predicted lipase regulatory gene was identified in addition to the previously characterized ctf1. The transcription profile of thirteen lipase genes during tomato plant colonization revealed that lip1, lip3, and lip22 were highly induced between 21 and 96 h after inoculation. Deletion mutants in five lipase genes (lip1, lip2, lip3, lip5, and lip22) and in the regulatory genes ctf1 and ctf2 as well as a Δctf1Δctf2 double mutant were generated. Quantitative reverse transcription-polymerase chain reaction expression analyses of structural lipase genes in the Δctf1, Δctf2, and Δctf1Δctf2 mutants indicated the existence of a complex lipase regulation network in F. oxysporum. The reduction of total lipase activity, as well as the severely reduced virulence of the Δctf1, Δctf2, and Δctf1Δctf2 mutants, provides evidence for an important role of the lipolytic system of this fungus in pathogenicity.

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33

Nguyen, Van Thi Ai, Hoa Ngoc Phan, Lam Bich Tran y Ai Tran Diem Chau. "Enzymatic hydrolysis of coconut oil using free and immobilized porcine pancreas lipases". Science and Technology Development Journal 19, n.º 2 (30 de junio de 2016): 70–77. http://dx.doi.org/10.32508/stdj.v19i2.654.

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The aim of this study is to evaluate the effect of some factors on the hydrolysis of coconut oil (CO) in the present of two kind of enzymes, the free lipases and immobilized lipases porcine pancreas. The activities of these two lipases under the optimal hydrolysis conditions was determined. The effects of factors on hydrolysis degree of coconut oil was investigated: the ratio of enzyme to substrate, the pH condition, and the temperature. The best conditions for the high hydrolysis degree in case of using lipase from porcine pancreas ascatalyst included: the ratio of the enzyme to substrate of 90(U/mL), and the pH condition of 8.5 at the temperature of 40oC. The best reaction condition the case of using immobilized porcine pancreas lipase as the catalyst was determined, including: the ratio enzyme to substrate of 393U/g, the pH condition of 7.5 and the temperature of 35oC. The hydrolysis degree of CO by immobilized porcine pancreas lipase was increased slower than free lipase at the first time. The highest hydrolysis degree achieved with immobilized porcine pancreas and free porcine pancreas lipase was 72.26% and 68.61%, respectively.

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34

Sargison, Fiona, Mariya I. Goncheva, Joana Alves, Amy Pickering y J. Ross Fitzgerald. "Staphylococcus aureus secreted lipases do not inhibit innate immune killing mechanisms". Wellcome Open Research 5 (25 de junio de 2021): 286. http://dx.doi.org/10.12688/wellcomeopenres.16194.2.

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Background: Staphylococcus aureus causes an array of diseases in both humans and livestock. Pathogenesis is mediated by a plethora of proteins secreted by S. aureus, many of which remain incompletely characterised. For example, S. aureus abundantly secretes two isoforms of the enzyme lipase into the extracellular milieu, where they scavenge upon polymeric triglycerides. It has previously been suggested that lipases may interfere with the function of innate immune cells, such as macrophages and neutrophils, but the impact of lipases on phagocytic killing mechanisms remains unknown. Methods: We employed the epidemic S. aureus clone USA300 strain LAC and its lipase deficient isogenic mutant, along with recombinant lipase proteins, in in vitro experimental infection assays. To determine if lipases can inhibit innate immune killing mechanisms, the bactericidal activity of whole blood, human neutrophils, and macrophages was analysed. In addition, gentamycin protection assays were carried out to examine the influence of lipases on S. aureus innate immune cell escape. Results: There were no differences in the survival of S. aureus USA300 LAC wild type and its lipase-deficient isogenic mutant after incubation with human whole blood or neutrophils. Furthermore, there was no detectable lipase-dependent effect on phagocytosis, intracellular survival, or escape from both human primary and immortalised cell line macrophages, even upon supplementation with exogenous recombinant lipases. Conclusions: S. aureus lipases do not inhibit bacterial killing mechanisms of human macrophages, neutrophils, or whole blood. These findings broaden our understanding of the interaction of S. aureus with the innate immune system.

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35

Sargison, Fiona, Joana Alves, Amy Pickering y J. Ross Fitzgerald. "Staphylococcus aureus secreted lipases do not inhibit innate immune killing mechanisms". Wellcome Open Research 5 (9 de diciembre de 2020): 286. http://dx.doi.org/10.12688/wellcomeopenres.16194.1.

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Background: Staphylococcus aureus causes an array of diseases in both humans and livestock. Pathogenesis is mediated by a plethora of proteins secreted by S. aureus, many of which remain incompletely characterised. For example, S. aureus abundantly secretes two isoforms of the enzyme lipase into the extracellular milieu, where they scavenge upon polymeric triglycerides. It has previously been suggested that lipases may interfere with the function of innate immune cells, such as macrophages and neutrophils, but the impact of lipases on phagocytic killing mechanisms remains unknown. Methods: We employed the epidemic S. aureus clone USA300 strain LAC and its lipase deficient isogenic mutant, along with recombinant lipase proteins, in in vitro experimental infection assays. To determine if lipases can inhibit innate immune killing mechanisms, the bactericidal activity of whole blood, human neutrophils, and macrophages was analysed. In addition, gentamycin protection assays were carried out to examine the influence of lipases on S. aureus innate immune cell escape. Results: There were no differences in the survival of S. aureus USA300 LAC wild type and its lipase-deficient isogenic mutant after incubation with human whole blood or neutrophils. Furthermore, there was no detectable lipase-dependent effect on phagocytosis, intracellular survival, or escape from both human primary and immortalised cell line macrophages, even upon supplementation with exogenous recombinant lipases. Conclusions: S. aureus lipases do not inhibit bacterial killing mechanisms of human macrophages, neutrophils, or whole blood. These findings broaden our understanding of the interaction of S. aureus with the innate immune system.

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36

Kumar, R. Ranjith, S. Kiran, S. Girisham y SM Reddy. "Lipase production by three thermophilic fungi". Indian Journal of Applied Microbiology 25, n.º 02 (13 de septiembre de 2023): 37–46. http://dx.doi.org/10.46798/ijam.2023.v25i02.3.

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Production of lipases by three thermophilic fungi, Thermomyces lanuginosus, Talaromyces luteus and Rhizomucor pusillus was investigated, influence of substratum, pH, temperature, carbon and nitrogen sources on lipase production was also studied. All the three fungi under study produced good amount of lipase constitutively. Lipase production was maximum at 45oC and it was thermostable.

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37

Gutiérrez-Domínguez, Denise Esther, Bartolomé Chí-Manzanero, María Mercedes Rodríguez-Argüello, Jewel Nicole Anna Todd, Ignacio Islas-Flores, Miguel Ángel Canseco-Pérez y Blondy Canto-Canché. "Identification of a Novel Lipase with AHSMG Pentapeptide in Hypocreales and Glomerellales Filamentous Fungi". International Journal of Molecular Sciences 23, n.º 16 (19 de agosto de 2022): 9367. http://dx.doi.org/10.3390/ijms23169367.

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Lipases are enzymes that hydrolyze triglycerides to fatty acids and glycerol. A typical element in lipases is a conserved motif of five amino acids (the pentapeptide), most commonly G-X-S-X-G. Lipases with the pentapeptide A-X-S-X-G are present in species of Bacillus, Paucimonas lemoignei, and the yeast Trichosporon asahii; they are usually thermotolerant and solvent resistant. Recently, while searching for true lipases in the Trichoderma harzianum genome, one lipase containing the pentapeptide AHSMG was identified. In this study, we cloned from T. harzianum strain B13-1 the lipase ID135964, renamed here as ThaL, which is 97.65% identical with the reference. We found that ThaL is a lid-containing true lipase of cluster III that belongs to a large family comprising highly conserved proteins in filamentous fungi in the orders Hypocreales and Glomerellales, in which predominantly pathogenic fungi are found. ThaL was expressed in conidia, as well as in T. harzianum mycelium, where it was cultured in liquid minimal medium. These results—together with the amino acid composition, absence of a signal peptide, mitochondrial sorting prediction, disordered regions in the protein, and lineage-specific phylogenetic distribution of its homologs—suggest that ThaL is a non-canonical effector. In summary, AHSMG-lipase is a novel lipase family in filamentous fungi, and is probably involved in pathogenicity.

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Nallapan Maniyam, Maegala, Anupriya Sundarajoo, Hazeeq Hazwan Azman, Nor Suhaila Yaacob y Hasdianty Abdullah. "Effect of inoculum size, inducer and metal ion on lipase production by Rhodococcus strain UCC 0009". E3S Web of Conferences 211 (2020): 02012. http://dx.doi.org/10.1051/e3sconf/202021102012.

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Lipases are critical enzymes for industrial applications such as in the food and pharmaceutical fields. Therefore, the discovery of new lipases with enhanced characteristics are always encouraged. Thus, the present study explored the ability of a novel bacterial strain isolated from a tropical climate for lipase production. The optimization method using the one-variable-at-a-time approach was adopted to obtain increased production of lipase. The strain identified as Rhodococcus strain UCC 0009 was able to generate specific lipase activity of 11.67a ± 0.00 mU/mg at optimized conditions of 8 % (v/v) inoculum concentration, 1 % (v/v) olive oil as the inducer, and the addition of Ca2+ions. The specific lipase activity increased by 162 % when the optimization using a one-variable-ata-time approach was adopted compared to that of the non-optimized counterpart, signifying this experimental phase’s importance. The present study’s findings revealed the potential of utilizing Rhodococcus strain UCC 0009 as a green lipase producer for application in bioremediation and biotransformation at an industrial scale. Further study concentrating on enzyme characterization and improving culture conditions for conducive production of lipase via statistical optimization using response surface methodology (RSM) will be attempted to elucidate further the superiority of lipase obtained from local resources.

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Kumar, Naren Gajenthra, Daniel Contaifer, Dayanjan S. Wijesinghe y Kimberly K. Jefferson. "Staphylococcus aureus Lipase 3 (SAL3) is a surface-associated lipase that hydrolyzes short chain fatty acids". PLOS ONE 16, n.º 10 (7 de octubre de 2021): e0258106. http://dx.doi.org/10.1371/journal.pone.0258106.

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Bacterial lipases play important roles during infection. The Staphylococcus aureus genome contains several genes that encode well-characterized lipases and several genes predicted to encode lipases or esterases for which the function has not yet been established. In this study, we sought to define the function of an uncharacterized S. aureus protein, and we propose the annotation S. aureus lipase 3 (SAL3) (SAUSA300_0641). We confirmed that SAL3 is a lipase and that it is surface associated and secreted through an unknown mechanism. We determined that SAL3 specifically hydrolyzes short chain (4-carbon and fewer) fatty acids and specifically binds negatively charged lipids including phosphatidic acid, phosphatidylinositol phosphate, and phosphatidylglycerol, which is the most abundant lipid in the staphylococcal cell membrane. Mutating the catalytic triad S66-A, D167-A, S168-A, and H301-A in the recombinant protein abolished lipase activity without altering binding to host lipid substrates. Taken together we report the discovery of a novel lipase from S. aureus specific to short chain fatty acids with yet to be determined roles in host pathogen interactions.

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40

Smith, G. M., K. Rothwell, S. L. Wood, S. J. Yeaman y M. Bownes. "Specificity and localization of lipolytic activity in adult Drosophila melanogaster". Biochemical Journal 304, n.º 3 (15 de diciembre de 1994): 775–79. http://dx.doi.org/10.1042/bj3040775.

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The triacylglycerol lipases present in adult Drosophila melanogaster have been investigated. Different lipase activities are present in various tissues in the fly. In particular, an abundant lipase activity is present in the male accessory gland. An esterase null mutant was used to confirm that the enzyme activity was due to a distinct lipase and not non-specific activity from esterase 6 which is also abundant in accessory glands. The properties of the accessory-gland lipase were investigated, and pH optima and substrate utilization suggest that it has some similarities to vertebrate bile-salt-stimulated lipase. Lipase activity is significantly reduced in males and increased in females shortly after mating. This finding suggests that lipase activity is transferred to the female and may be important in mating and reproduction in Drosophila.

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41

Ehlert, Janna, Jenny Kronemann, Nadine Zumbrägel y Matthias Preller. "Lipase-Catalyzed Chemoselective Ester Hydrolysis of Biomimetically Coupled Aryls for the Synthesis of Unsymmetric Biphenyl Esters". Molecules 24, n.º 23 (23 de noviembre de 2019): 4272. http://dx.doi.org/10.3390/molecules24234272.

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Lipases are among the most frequently used biocatalysts in organic synthesis, allowing numerous environmentally friendly and inexpensive chemical transformations. Here, we present a biomimetic strategy based on iron(III)-catalyzed oxidative coupling and selective ester monohydrolysis using lipases for the synthesis of unsymmetric biphenyl-based esters under mild conditions. The diverse class of biphenyl esters is of pharmaceutical and technical relevance. We explored the potency of a series of nine different lipases of bacterial, fungal, and mammalian origin on their catalytic activities to cleave biphenyl esters, and optimized the reaction conditions, in terms of reaction time, temperature, pH, organic solvent, and water–organic solvent ratios, to improve the chemoselectivity, and hence control the ratio of unsymmetric versus symmetric products. Elevated temperature and increased DMSO content led to an almost exclusive monohydrolysis by the four lipases Candida rugosa lipase (CRL), Mucor miehei lipase (MML), Rhizopus niveus lipase (RNL), and Pseudomonas fluorescens lipase (PFL). The study was complemented by in silico binding predictions to rationalize the observed differences in efficacies of the lipases to convert biphenyl esters. The optimized reaction conditions were transferred to the preparative scale with high yields, underlining the potential of the presented biomimetic approach as an alternative strategy to the commonly used transition metal-based strategies for the synthesis of diverse biphenyl esters.

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42

Ramos, Margarita Díaz, Letícia Passos Miranda, Roberto Fernandez-Lafuente, William Kopp y Paulo Waldir Tardioli. "Improving the Yields and Reaction Rate in the Ethanolysis of Soybean Oil by Using Mixtures of Lipase CLEAs". Molecules 24, n.º 23 (1 de diciembre de 2019): 4392. http://dx.doi.org/10.3390/molecules24234392.

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Due to the heterogeneity of oils, the use of mixtures of lipases with different activity for a large number of glycerol-linked carboxylic acids that compose the substrate has been proposed as a better alternative than the use of one specific lipase preparation in the enzymatic synthesis of biodiesel. In this work, mixtures of lipases from different sources were evaluated in their soluble form in the ethanolysis of soybean oil. A mixture of lipases (50% of each lipase, in activity basis) from porcine pancreas (PPL) and Thermomyces lanuginosus lipase (TLL) gave the highest fatty acid ethyl ester (FAEE) yield (around 20 wt.%), while the individual lipases gave FAEE yields 100 and 5 times lower, respectively. These lipases were immobilized individually by the cross-linked enzyme aggregates (CLEAs) technique, yielding biocatalysts with 89 and 119% of expressed activity, respectively. A mixture of these CLEAs (also 50% of each lipase, in activity basis) gave 90.4 wt.% FAEE yield, while using separately CLEAs of PPL and TLL, the FAEE yields were 84.7 and 75.6 wt.%, respectively, under the same reaction conditions. The mixture of CLEAs could be reused (five cycles of 6 h) in the ethanolysis of soybean oil in a vortex flow-type reactor yielding an FAEE yield higher than 80% of that of the first batch.

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Kahveci, Derya, Mia Falkeborg, Sandra Gregersen y Xuebing Xu. "Upgrading of Farmed Salmon Oil Through Lipase-Catalyzed Hydrolysis". Open Biotechnology Journal 4, n.º 1 (29 de diciembre de 2010): 47–55. http://dx.doi.org/10.2174/1874070701004010047.

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Upgrading of farmed salmon oil obtained from by-products was carried out by lipase-catalyzed hydrolysis to increase omega 3 polyunsaturated fatty acids (PUFA) content. The lipases tested were from Penicillium camembertii (PC), Rhizomucor javanicus (RJ), Rhizopus niveus (RN), Rhizopus delemar (RD), Burkholderia cepacia (BC), Rhizopus oryzae (RO), Candida rugosa (CR) and Rhizomucor miehei (RM). The lipases from PC, RJ and RN had lower hydrolysis degrees (HDs) compared to the rest of the lipases. The lipase from CR had the highest HD after 24 h (91.89%). Moreover, CR lipase was the most effective one in concentrating omega 3 PUFA. The final value was increased from 13.77% to 27.81% (wt%). The changes in omega 3 PUFA content were significantly different among the lipases although the HD values were similar at the end of the reactions, which was believed to be caused by the substrate specificities of the lipases. The investigation of the relationship between HD and hydrolysis resistant value (HRV) for eicosapentaenoic acid (EPA, 20:5), docosahexaenoic acid (DHA, 22:6) and oleic acid (OA, 18:1) revealed that the fatty acid (FA) selectivity of the lipases were significantly different. CR lipase had the highest preference for hydrolyzing OA selectively over EPA and DHA. The reaction conditions, i.e. presence of surfactants, sonication, buffer-to-oil ratio, enzyme load, did not affect the selectivity. Investigation of the reaction conditions revealed that it was possible to obtain ~2.15-fold of the original omega 3 PUFA content by hydrolysis of salmon oil in the presence of CR lipase (4%, based on oil weight) with a bufferto- oil ratio of 2:1 (v/v) at 37oC for 4 h.

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Al- Khafaji, K. A. A., S. G. Omran, Manal Al-Latef Hasan, A. S. Salman y S. A. Rheem Mahmood. "Detection of biological active substances and lipase inhibitors from aqueous extracts of some legumes in comparison with Orlistat drug". Journal of Biotechnology Research Center 8, n.º 4 (1 de diciembre de 2014): 35–40. http://dx.doi.org/10.24126/jobrc.2014.8.4.378.

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This research was aimed to determine biological active substances qualitatively in vicia faba, lentil, green peas, soybean, beans, redbean. Lipase inhibitors were screened and compared with orlistat drug. All cold and hot extracts contained both saponin and tannin while polyphenol did not exist in vicia faba and soybean; rating found in all extracts except greenbeas. Tween 80 was used in lipase and lipase inhibitors screening; lipases activity were detected at cold aqoueus extracts of vicia faba, lentil, redbean and beans while heat stable lipase detected at vicia faba hot extract only. Extracts of Green peas, soy beans and chick pea lacking lipase activity. Qualitative and quantitative determination of lipase inhibitors activity showed that soybean and chick pea gave the highest lipase inhibition. Each extract caused 100% inhibition with 472.5 unit/ml compared with 85% inhibition for 12 mg/ ml of orlistat.

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Wang, Jiale, Jiqiang Song, Qi Fang, Hongwei Yao, Fang Wang, Qisheng Song y Gongyin Ye. "Insight into the Functional Diversification of Lipases in the Endoparasitoid Pteromalus puparum (Hymenoptera: Pteromalidae) by Genome-scale Annotation and Expression Analysis". Insects 11, n.º 4 (5 de abril de 2020): 227. http://dx.doi.org/10.3390/insects11040227.

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Lipases play essential roles in digestion, transport, and processing of dietary lipids in insects. For parasitoid wasps with a unique life cycle, lipase functions could be multitudinous in particular. Pteromalus puparum is a pupal endoparasitoid of butterflies. The female adult deposits eggs into its host, along with multifunctional venom, and the developing larvae consume host as its main nutrition source. Parasitoid lipases are known to participate in the food digestion process, but the mechanism remains unclear. P. puparum genome and transcriptome data were interrogated. Multiple alignments and phylogenetic trees were constructed. We annotated a total of 64 predicted lipase genes belonging to five lipase families and suggested that eight venom and four salivary lipases could determine host nutrition environment post-parasitization. Many putative venom lipases were found with incomplete catalytic triads, relatively long β9 loops, and short lids. Data analysis reveals the loss of catalytic activities and weak triacylglycerol (TAG) hydrolytic activities of lipases in venom. Phylogenetic trees indicate various predicted functions of lipases in P. puparum. Our information enriches the database of parasitoid lipases and the knowledge of their functional diversification, providing novel insight into how parasitoid wasps manipulate host lipid storage by using venom lipases.

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Joshi, Ritika y Arindam Kuila. "Lipase and their different industrial applications: A review". Brazilian Journal of Biological Sciences 5, n.º 10 (2018): 237–47. http://dx.doi.org/10.21472/bjbs.051004.

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Enzymes are also known natural catalysts. Lipases are flexible enzymes that are mostly used. These enzymes are found extensively all over the animal and plant kingdoms, likewise in molds and bacteria. Among all identified enzymes, lipases have concerned the mainly biotechnological attention. This review paper discusses the characteristic, microbial origin and application of lipases. The present review discussed about different characteristics and sources (fungal, bacteria’s) of lipase. The present article also discussed about different bioreactors used for lipase production and different biotechnological applications (food, detergent, paper and pulp, biofuels etc) of lipases. An observation to considerate lipases and their applications as bulk enzymes and high-value of production, these enzymes are having huge impact in different bioprocesses.

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47

Barron, Luis JR, Igor Hernández, Ainhoa Bilbao, Cristian E. Flanagan, Ana I. Nájera, Mailo Virto, Francisco J. Pérez-Elortondo, Marta Albisu y Mertxe de Renobales. "Changes in lipid fractions and sensory properties of Idiazabal cheese induced by lipase addition". Journal of Dairy Research 71, n.º 3 (23 de julio de 2004): 372–79. http://dx.doi.org/10.1017/s0022029904000135.

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This work studied the addition of an adequate lipase to enhance lipolysis reactions and the development of piquant flavour and sharp odour in Idiazabal cheese, as an alternative to the use of lamb rennet paste. Cheeses were manufactured from bulk raw ewes' milk in 50 l vats with commercial bovine rennet and 80 lipase units of pregastric or 180 lipase units of fungal lipase and ripened for 180 days. A higher lipolytic activity was induced by lipase addition promoting strong changes in odour and flavour attributes. Both fungal and pregastric lipases increased the content of total free fatty acids (FFA), but the fungal lipase released mainly medium- and long-chain FFA. In contrast, the pregastric lipase preferably released short-chain FFA. Diglyceride (DG) content was considerably higher in cheeses made with added pregastric lipase compared with those made with fungal lipase or with no lipase. Monoglycerides (MG) were detected only in cheeses made with either lipase added, reaching comparable concentrations after ripening for 180 days. The cheeses made with pregastric lipase had the highest scores for odour and flavour intensity, and sharp and rennet odours, desirable attributes for the Idiazabal cheese made with lamb rennet paste. None of the texture attributes were significantly influenced by the concentrations of MG and DG in the cheeses made with either lipase. Thus, the pregastric lipase was more appropriate than the fungal lipase to develop a more traditionally-flavoured Idiazabal cheese.

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Salleh, A. B., R. Musani, M. Basri, K. Ampon, W. M. Z. Yunus y C. N. A. Razak. "Extra- and intra-cellular lipases from a thermophilic Rhizopus oryzae and factors affecting their production". Canadian Journal of Microbiology 39, n.º 10 (1 de octubre de 1993): 978–81. http://dx.doi.org/10.1139/m93-147.

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A thermophilic Rhizopus oryzae was isolated, and parameters affecting its production of extra- and intra-cellular lipases were investigated. All carbon sources tested with the exception of sucrose generally inhibited the production of extracellular lipase, but enhanced the production of intracellular lipase. Peptone was the best substrate for extracellular enzyme production, but for intracellular lipase production other substrates such as tryptone, tryptic soy digest, polypeptone, and corn steep liquor gave comparable results. Among lipid substrates, glycerol was the only stimulator of extracellular enzyme production, whereas olive oil, triolein, and oleic acid had very positive effects on intracellular enzyme production. Shaking enhanced the production of both types of enzymes; the temperature optima were 45 and 37 °C for extra- and intra-cellular lipases, respectively. A pH of 5.0 was optimal for production of both enzymes.Key words: lipases, Rhizopus oryzae, production.

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Nhat, Dang Minh y Phan Thi Viet Ha. "The isolation and characterization of lipase from Carica papaya latex using zwitterion sodium lauroyl sarcosinate as agent". Potravinarstvo Slovak Journal of Food Sciences 13, n.º 1 (28 de octubre de 2019): 773–78. http://dx.doi.org/10.5219/1164.

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Most of industrial lipases are derived from microbial sources, following by a wide variety of plants. Among plant lipases, lipase from Carica papaya latex has been the focus of intense and growing research due to low cost, easy acceptance by consumers and its unique characteristics. This enzyme has been successfully applied for lipid modification and synthesis of some organic compounds. However, research for its molecular structure has been limited due to the difficulty to isolate the enzyme from the latex matrix. In this study, we suggested a modified approach using sodium lauroyl sarcosinate to solubilize the latex, then the protein was precipitated by ammonium sulphate. We also carried out the characterization of the lipase obtained from Carica papaya latex. The results showed that freeze-drying the fresh latex could improve significantly lipase activity of latex powder in comparison with sun-drying or oven-drying. The zwitterion sodium lauroyl sarcosinate could solubilize nearly 50% of the latex and the achieved supernatant exhibited great lipase activity. There was no need to use an organic solvent to delipidate the latex prior to solubilization with sodium lauroyl sarcosinate due to possible denaturation of enzymes. The proteins which were fractionally precipitated with 50 – 60%, 60 – 70% and 70 – 80% ammonium sulphate saturation showed lipolytic activity. The fraction from 50 – 60% saturation with the greatest mass was subjected to ion exchange chromatography, SDS electrophoresis and kinetic parameter determination. The results showed the presence of two proteins with molecular mass ranging from 35 kDa to 55 kDa and both presented lipase activity. The Km and Vmax of the lipase fraction from 50 – 60% saturation was 1.12 mM and 1.2 x 10-6 mM.min-1.mL-1 respectively. So, the freeze-drying of papaya latex could help to preserve its lipase activity and the usage of sodium lauroyl sarcosinate could improve the isolation of the lipase from the papaya latex and pave the way for research on the molecular structure of Carica papaya latex lipases.

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Alabdalall, Amira Hassan, Norah Ayad ALanazi, Sumayh A. Aldakeel, Sayed AbdulAzeez y J. Francis Borgio. "Molecular, physiological, and biochemical characterization of extracellular lipase production by Aspergillus niger using submerged fermentation". PeerJ 8 (7 de julio de 2020): e9425. http://dx.doi.org/10.7717/peerj.9425.

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Background Extracellular production of fungal lipases especially the lipases obtained from the Aspergilli has gained immense interest in recent years due to its diverse biotechnological applications. In this study, we focused on determining the fermentation parameters required for the optimal lipase production. Methods A total of 256 fungal isolates were obtained from oil seeds. From each genus, one isolate was selected to evaluate lipase production using phenol red and tributyrin plate assays. Lipase activity was estimated using the spectrophotometric pNPP hydrolysis assay. The highest lipase producer isolates were identified using 18S ribosomal RNA gene sequencing. The genetic variability was determined by random amplified polymorphic DNA (RAPD) analysis and the dendrogram was constructed using the unweighted pair group method with arithmetic averages method. The isolates were examined in a submerged fermentation culture (Smf) to measure the effect of temperature, pH, incubation time, carbon source, nitrogen source, inoculum volume, and lipid source on lipase production. Results Eleven isolates belonging to the genus Aspergillus were analyzed for lipase production where they were found to be the highest lipase producers among various fungal genera. All the tested isolates were identified as A. niger using 18s rRNA sequencing. Genetic diversity was evaluated among all of the studied A. niger isolates using RAPD primers. The RAPD primers were used to amplify 285 loci, of which five were polymorphic (1.75%) and seven were monomorphic (2.45%). Thus, a high level of genetic diversity was observed among all isolates. The tributyrin test and the lipase activity assay identified five strains of A. niger as high lipase producers, and their optimal enzyme activities were 709.74, 532.54, 735.64, 794.62, and 787.69 U/ml. The optimal conditions for lipase production were as follows: 40 °C, pH 7.5, 1% fructose as the carbon source, 1% yeast extract as the nitrogen source, 2% palm oil, 2.5 × 107 spores/ml suspension, and 3 days of incubation. Conclusions The current study provides a comprehensive characterization of the optimal conditions, which are essential to enhance lipase production in five A. niger isolates.

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