Study on the Properties of Immobilized Biocatalysts with Lipase Activity Produced by Yarrowia lipolytica in Batch Culture

Three kinds of matrices (calcium alginate, gelatin, and PVA) were employed as supports to immobilize lipases from Y. lipolytica KKP 379 via physical adsorption. The stability of biocatalysts (free and immobilized) was evaluated by measuring the enzyme activity before and after treatment with the method based on the hydrolysis of p-nitrophenyl laurate. Two fractions of enzymes were immobilized: cell-bound (yeast biomass) and extracellular (supernatant). The yield of immobilization and catalytic properties of immobilized lipases were investigated. Satisfactory results for lipolytic activity and biocatalyst stability were obtained for cell-bound enzymes immobilized in alginate (0.38 U g–1 d.m.) and crosslinked gelatin (0.18 U g–1 d.m.). Immobilization of the supernatant was successful only on the alginate (0.026 U g–1 d.m.). After lyophilization, no significant difference was noticed between treated and untreated biocatalysts. Lyophilized catalysts were successfully immobilized in all three matrices, but the process reduced their lipolytic activity probably due to an insufficient amount of water in the reaction solution. This work is licensed under a Creative Commons Attribution 4.0 International License

Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus -- the "D-shuttle" project --

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter "D-shuttle" for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the background radiation level of other regions/countries

The attempt to apply Yarrowia Lipolytica KKP379 yeast in fishery industry wastes management

Celem pracy przedstawionej w artykule była ocena możliwości zastosowania kilku produktów odpadowych pochodzących z przetwórni ryb (solanki, dwóch rodzajów odpadów po procesie wędzenia ryb oraz szlamu) jako źródła węgla do wzrostu dzikiego szczepu drożdży Y. lipolytica KKP 379. Najwyższy średni plon biomasy drożdży uzyskano w podłożu zawierającym szlam jako źródło węgla, natomiast najwyższą średnią aktywność lipolityczną oznaczono w płynie pohodowlanym z podłoża zawierającego olej odpadowy po procesie wędzenia. Wprawdzie średnia zewnątrzkomórkowa aktywność lipolityczna drożdży była niższa w porównaniu z uzyskaną w podłożu z oliwą z oliwek (znanym aktywatorem syntezy lipaz), ale zaletą przedstawionego rozwiązania mogą być względy ekonomiczne i ekologiczne.The aim of the study presented in the paper was to evaluate the possibility of application some fishery wastes (oily wastes from fish smoking process, fish leach and sludge) as a carbon sources in the culture medium for wild strain of yeast Y. lipolytica KKP 379. The highest average yeast biomass yield was achieved in the presence of sludge, but the highest lipase activity was observed in the presence of oily wastes from fish smoking process. The extracellular lipase activity in the culture medium was lower than that obtained in the presence of oil olive (the common activator of lipase synthesis), however this approach may be recommended due to the economic and environmental reasons

Utilization of waste from food and fuel industries by lipolytic yeast of Yarrowia lipolytica

Przemysł spożywczy i paliwowy wytwarzają znaczne ilości trudnych w utylizacji hydrofobowych odpadów, stąd istnieje potrzeba poszukiwania nowych metod ich zagospodarowania. Celem badań była ocena możliwości zastosowania wybranych hydrofobowych odpadów przemysłu spożywczego i paliwowego jako głównego źródła węgla oraz induktora syntezy enzymów lipolitycznych w hodowli szczepu drożdży Yarrowia lipolytica W29. Hodowle wstrząsane prowadzono przez 65 h w 28°C w zmodyfikowanym podłożu YPG, w którym glukoza została zastąpiona olejem po procesie wędzenia ryb, tłuszczem po procesie wędzenia wędlin wieprzowych, tłuszczem po pieczeniu kaczej tuszki, zjełczałym masłem klarowanym lub zużytym olejem silnikowym. Stwierdzono, że odpady te mogą być wykorzystywane jako źródło węgla w hodowli drożdży Y. lipolytica. Produkcję enzymów lipolitycznych zaobserwowano w podłożach zawierających tłuszczowe substraty, a aktywność enzymów korelowano ze składem kwasów tłuszczowych. Wykazano, że istnieje możliwość utylizacji zastosowanych substratów odpadowych w procesach mikrobiologicznych do syntezy enzymów o aktywności lipolitycznej.Waste disposal and by-product management in many branches of industry pose problems in the areas of environmental protection and sustainability. Hydrophobic waste substrates of food and fuel origin stands for one of the continuously gaining ground for waste management fields. The aim of the study was to evaluate the possibility to use food origin wastes and fuel industry waste as a carbon sources in the culture medium for Y. lipolytica W29 with their simultaneous valorization. Culture media contained 2% of waste substrates. In the study there were evaluated yeast biomass yield, number of yeast cells in 1 cm³ of medium and extracellular lipase activity after 65 h of yeast growth on a rotary shaker at 28°C. Five wastes were estimated: oily waste from duck roasting process, oily waste from sausages smoking process, rancid ghee, oily waste from fish smoking process and waste engine oil. Additionally fatty acid composition of lipid waste was analyzed using gas chromatography. It was shown the possibility of using these wastes in cultivation of yeast with their simultaneous valorization by obtaining valuable products, e.g. enzymes such as extracellular lipases as well as biomass intended for feed. Yeast biomass yielded from 19.77 g DM·dm⁻³ for oily waste from duck roasting process to 12.28 g DM·dm⁻³ for oily waste from fish smoking process. It has been found that waste substrates stimulate the synthesis of extracellular lipases with different efficiency. The highest activity was obtained in medium containing smoked fish oil (0.313 U·cm⁻³). Furthermore, in waste engine oil medium no lipase activity of Y. lipolytica yeast was observed, but cells did grow and formed a biofilm. The analysis of fatty acid compositions showed the highest oleic acid content in oily waste from duck roasting process (41.9%), slightly lower waste from sausages smoking process (37.8%) and two-fold lower in fish oil (17.3%). This is very important information, because some authors believe that lipolytic enzymes synthesized by the yeast Y. lipolytica show substrate specificity as compared to that oil. Furthermore, the waste oil from fish smoking process was characterized by the presence of polyunsaturated fatty acids containing more than 20 carbons in chain length (EPA and DHA). There was no correlation between lipolytic activity and oleic acid content in waste fat used as the carbon source in medium, but it can be concluded that Y. lipolytica yeast prefered unsaturated rather than saturated fatty acids in extracellular lipase production