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1

Fungus lipases and their activity in the hydrolisis reaction and in the synthesis of fatty acid esters

100%
Antczak T., Krystynowicz A., Galas E.
Biotechnologia
|
1995
|
issue 2
82-91
EN
Preparations of soluble and immobilized fungus lipases showing high catalityc acivity in hydrolysis of acyloglycerols in water, synthesis of esters of higher fatty acids in hydrolysis of acyloglycerols in water and synthsis of esters of higher fatty acids inorganic solvents milieu were obtained.The course of reaction andthe activity dependedon: the lipase source, the form of enzyme and the reaction milieu.The studied extacellular lipases, in a water - soluble form (especially R.nigricans lipase), exibited high activity in olive oil hydrolisis.The lipases were not active in esters synthesis in diphase system: water-organic solvent.Being drained by liophilization they demonstrated the activity in esters synthesis inorgnic solvents milieu.The endocellular lipases immobilized in situshowed the hihgest activity in the synthesis of esters in organic milieu.These enzymes can also be used for hydrolysis of acyloglycerols.The obtained liquid and immobilized mycelial preparations demonstrate activity which qualifies them for industrial scale application.
2

Enzymatic hydrolysis of waste fats

100%
Antczak T., Krystynowicz A., Galas E.
Biotechnologia
|
2000
|
issue 2
120-130
EN
The intracellular lipases of Mucor circinelloides and Mucor racemosus immobilised in situ as well as the extracellular lipase of Rhizopus nigricans in soluble form were applied to enzymatic hydrolysis of waste fats from oil and meat industry, waste sludge of fats from municipal and industrial sewage-treatment plants and waste water containing microemulsion of fats. The reaction of hydrolysis of plant and animal waste fats was carried out by two methods. The first one was a partial hydrolysis of acylglycerols to obtain mono- and diacylglycerols. The second variant was complete hydrolysis of fats to obtain glycerol and free fatty acids. It has been demonstrated that lipase of Rhizopus nigricans partly hydrolysed waste fats. The products of hydrolysis contained 35-45% mono- and diacylglycerols. These products may be used as emulsifier in the hydrolysis of fats. The yield of hydrolysis of waste fats by immobilised Mucor lipases was from 85 up to over 95%. Waste sludge of fats from municipal and industrial sewage contain 12-62% of free fatty acids. This kind of material was hydrolysed without an emulsifier but with the addition of calcium chloride. The yield of hydrolysis of acylglycerols was from 45 to 76%. The yield of hydrolysis of microemulsion of fats in waste water by immobilised Mucor lipases was from 80 up to over 95%. As the hydrolysis products contained free fatty acids, mono- and diacylglycerols, it was easy to make emulsions which could be utilised in anaerobic-aerobic processes.
3

Biosynthesis of bacterial cellulose and its application

100%
Krystynowicz A., Turkiewicz M., Drynska E., Galas E.
Biotechnologia
|
1995
|
issue 3
120-132
EN
Biosynthesis of bacterial cellulose and its potential applicationa are presented.The mechanism of cellulose biosynthesis in Acetobacter xylinum, the regulatory pathways and the polymer structure are described.Some biotechnological aspects of polysaccharide production and industrially valuable features of bacterial callulose are also discussed.
4

Mathematical modelling of sugar esters synthesis catalyzed by Mucor circinelloides lipase in non water environment

88%
Antczak T., Krystynowicz A., Hiler D., Bielecki S., Galas E.
Biotechnologia
|
1999
|
issue 1
153-163
EN
A mathematical model describing sucrose esters synthesis in biphasic di-n-phentyl ether - water system by lipase from Mucor circinelloides has been elaborated. This model considers correlation between physicochemical factors, dependent on the solvent, substrates, products and temperature, catalytic factors corresponding to the relationship between lipase and the physicochemical factors of the model (Ko=F(A)), as well quantitative factors whose values may be regulated during the reaction (substrate concentration, phase volume coefficient (A) and water concentration). This model was confirmed by syntheses of caprylic and oleic sucrose esters. The maximum reaction yield for the synthesis of caprylic sucrose ester calculated on the basis of the elaborated model was 67,5% and experimental value was 67,8% for A = 44. For oleic sucrose ester, the theoretical and experimental yields of synthesis, were 71,9% and 70,5% respectively. Using this model it is possible to estimate the maximum achievable (in particular conditions) yield of the ester synthesis. It can also be applied for simulations enabling evaluation of the effect of the particular factors on the yield of ester synthesis and resulting optimisation of selected factors in the reaction system. The simulations were performed for two factors of the model in three dimensional space. It was found that the ester synthesis was mostly affected by the following invariable factors: partition coefficients of products (PE, PW) and phase volume coefficient (A). The concentration of water in the water phase and the partition coefficients of sugar (PAL) influenced the yield to a smaller extent.
5

Characterization of selected bacterial strains degrading hydrocarbons of petroleum oil

76%
Galas E., Kwapisz E., Tarabasz-Szymanska A., Krystynowicz A., Antczak T., Orynska
Biotechnologia
|
1997
|
issue 1
145-157
EN
The results of special tests which had been carried out with the following bacterail strains Bacillus sp. S2, Bacillus sp. BP, Pseudomonas sp. 141 and Micrococcus sp. R5.4 show that these strains are acive degraders of petroleum oil hydrocarbons, tolerate high concentrations of the subsrtate and have a high capability for degradation of hydrocarbons.The activity of dehydrogenases was related to the concentration of the substrate.The gas chromatography analysis of residual hydrocarbons in the medium after 9 days of cultivation proved that the main identified petroleum oil components had been metabolized with the yield 69 to 100%. Apart from the compounds originally present in crude oil no new by-products were detected in final medium.The accumulation of shorter chain length hydrocarbons and various new by-products occured in the case of another tested bacterial strain, designated 'B'.
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