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1

Production and optimization of exocellular lipases produced by Proteus mirabilis

Nabrdalik M.

Proceedings of ECOpole

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2016

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Vol. 10, No. 2

447--454

EN

Lipases are produced by plants, animals and microorganisms, but only those produced by the microorganisms are important to industry due to their various enzymatic properties and substrate specificity. Despite the fact, that such enzymes are synthesized by many species of microorganisms, new environmental strains able to synthesize exocellular lipases are searched for. The aim of conducted research was to assess the lipolytic activity of Proteus mirabilis depending on pH and temperature. The activity was analysed in the pH range between 4-9 and temperatures 5-60ºC. The lipolytic activity was assessed by means of titration and the results were presented as the amount of released μmoles of fatty acids. The analysis of pH influence showed that the highest amount of μmoles of fatty acids was released by the strain under study at pH 4 (264.75 μmol/cm3). Synthesized lipases were most active at 35-45ºC and the amount of released μmoles of fatty acids ranged between 264.75 and 116.25 μmol/cm3. Lipases produced by P. mirabilis due to their biological activity showed in the wide range of pH and temperature may be an alternative to lipolytic products currently applied in the industry.

PL

Lipazy są wytwarzane przez rośliny, zwierzęta i mikroorganizmy, ale tylko te pochodzenia mikrobiologicznego są ważne dla przemysłu ze względu na zróżnicowane właściwości enzymatyczne i specyficzność substratową. Mimo że enzymy te są syntetyzowane przez wiele gatunków mikroorganizmów, to nadal poszukuje się nowych, środowiskowych szczepów zdolnych do syntezy zewnątrzkomórkowych lipaz. Celem przeprowadzonych badań była ocena aktywności lipolitycznej Proteus mirabilis w zależności od pH oraz temperatury. Aktywność lipolityczną analizowano w zakresie pH 4-9 oraz w temperaturach 5-60ºC. Do oznaczenia aktywności lipolitycznej posłużono się metodą miareczkową, a wyniki podano jako ilość uwolnionych μmoli kwasów tłuszczowych. Analizując wpływ pH, stwierdzono, iż najwięcej μmoli kwasów tłuszczowych badany szczep uwolnił przy pH 4 (264,75 μmol/cm3). Lipazy syntetyzowane przez badany szczep wykazywały największą aktywność, gdy reakcję prowadzono w zakresie temperatur 35-45ºC. Ilość uwolnionych wówczas μmoli kwasów tłuszczowych mieściła się w przedziale od 264,75 do 116,25 μmol/cm3. Lipazy P. mirabilis ze względu na aktywność biologiczną w szerokim zakresie pH oraz temperatury mogą stać się alternatywą dla obecnych na rynku preparatów lipolitycznych stosowanych w przemyśle.

2

Enzymatic activity of a novel halotolerant lipase from Haloarcula hispanica 2TK2

Ozgen M., Attar A., Elalmis Y., Birbir M., Yucel M.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 2

20--25

EN

A strain of Haloarcula hispanica isolated from Tuzkoy salt mine, Turkey exhibited extracellular lipolytic activity. Important parameters such as carbon sources and salt concentration for lipase production were investigated. Optimal conditions for the enzyme production from Haloarcula hispanica 2TK2 were determined. It was observed that the lipolytic activity of Haloarcula hispanica was stimulated by some of the carbon sources. The high lipase acitivity values were obtained in the presence of 2% (v/v) walnut oil (6.16 U/ml), 1% (v/v) fish oil (5.07 U/ml), 1% (v/v) olive oil (4.52 U/ml) and 1% (w/v) stearic acid (4.88 U/ml) at 4M NaCl concentration. Lipase was partially purified by ammonium sulfate precipitation and ultrafiltration. Optimal temperature and pH values were determined as 45oC and 8.0, respectively. Lipase activity decreased with the increasing salt concentration, but 85% activity of the enzyme was maintained at 5M NaCl concentration. The enzyme preserved 41% of its relative activity at 90oC. The partially purified lipase maintained its activity in the presence of surfactants such as Triton X-100 and SDS. Therefore, the lipase which is an extremozyme may have potential applications especially in detergent industry.

3

Physicochemical and biological characterization of soils from the vicinity of the Arctowski Polish Antarctic Station

Białkowska A. M, Grzelczyk A, Długołęcka A, Cieśliński H, Kalinowska H, Kur J, Turkiewicz M

Biotechnology and Food Science

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2012

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Vol. 76, nr 1

13--26

EN

Soil samples collected in 2006 from 4 different sites (Puchalski Hill and a moraine below this hill, an elephant seal colony and a penguin rookery) in the vicinity of Arctowski Polish Antarctic Station at King George Island were characterized in terms of physicochemical properties (pH, humidity, concentration of selected inorganic and organic substances), microbial colonization and the overall activity of selected enzymes (differentglycosidases and esterases). Activity of the latter enzymes was assayed by p-nitrophenyl and 4-methylumbelliferone derivatives of fatty acids (by spectrophotometric and fluorimetric method, respectively). The highest lipolytic activity was found in soils from the elephant seal colony and penguin rookery.

4

Evaluation of the enzymatic activity of selected bacterial strains

Wierzba S., Latała A.

Polish Journal of Chemical Technology

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2007

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Vol. 9, nr 2

68-72

EN

In these studies we attempted to evaluate the lipolytic, proteolytic and cellulolytic activity of bacterial strains isolated from water and the bottom sediments of Turawa Lake. The following bacterial genera prevailed among the isolated strains: Bacillus, Pseudomonas, Enterobacter, Cellulomonas and Cytophaga. The lipolytic activity was determined using a titrimetric method, the proteolytic activity - using a modified Anson method, and the cellulolytic activity - on the basis of mass decrement of a cellulose disk after 14 days of bacterial culture. The cultures were maintained at 28°C, pH 7.0 with the following substrates: olive oil, albumin and cellulose disk. Among the analysed microorganisms, Bacillus and Pseudomonas strains showed the highest lipolytic and proteolytic activity. In the cellulolytic assay Cytophaga bacteria showed about twofold higher activity than that of Celulomonas.