47 research outputs found
Screening and Identification of Trichoderma Strains Isolated from Natural Habitats with Potential to Cellulose and Xylan Degrading Enzymes Production
A total of 123 Trichoderma strains were isolated from different habitats and tested for their ability to degrade cellulose and xylan by simple plate screening method. Among strains, more than 34 and 45% respectively, exhibited higher cellulolytic and xylanolytic activity, compared to the reference strain T. reesei QM 9414. For strains efficiently degrading cellulose, a highest enzyme activity was confirmed using filter paper test, and it resulted in a range from 1.01 to 7.15 FPU/ml. Based on morphological and molecular analysis, the isolates were identified as Trichoderma. The most frequently identified strains belonged to Trichoderma harzianum species. Among all strains, the most effective in degradation of cellulose and xylose was T. harzianum and T. virens, especially those isolated from forest wood, forest soil or garden and mushroom compost. The results of this work confirmed that numerous strains from the Trichoderma species have high cellulose and xylan degradation potential and could be useful for lignocellulose biomass conversion e.g. for biofuel production
Biological Denitrification of High Nitrate Processing Wastewaters from Explosives Production Plant
Wastewater samples originating from an explosives production plant (3,000 mg N l−1 nitrate, 4.8 mg l−1 nitroglycerin, 1.9 mg l−1 nitroglycol and 1,200 mg l−1 chemical oxygen demand) were subjected to biological purification. An attempt to completely remove nitrate and to decrease the chemical oxygen demand was carried out under anaerobic conditions. A soil isolated microbial consortium capable of biodegrading various organic compounds and reduce nitrate to atmospheric nitrogen under anaerobic conditions was used. Complete removal of nitrates with simultaneous elimination of nitroglycerin and ethylene glycol dinitrate (nitroglycol) was achieved as a result of the conducted research. Specific nitrate reduction rate was estimated at 12.3 mg N g−1 VSS h−1. Toxicity of wastewater samples during the denitrification process was studied by measuring the activity of dehydrogenases in the activated sludge. Mutagenicity was determined by employing the Ames test. The maximum mutagenic activity did not exceed 0.5. The obtained results suggest that the studied wastewater samples did not exhibit mutagenic properties
Metagenomic Analysis of Soil Bacterial Community and Level of Genes Responsible for Biodegradation of Aromatic Hydrocarbons
Persistence of selected ammonium- and phosphonium-based ionic liquids in urban park soil microcosms
Biological denitrification of brine: the effect of compatible solutes on enzyme activities and fatty acid degradation
Persistence of selected ammonium- and phosphonium-based ionic liquids in urban park soil microcosms
Biodegradation of wastes from oil industry by composting process
Celem pracy było zbadanie możliwości biodegradacji odpadu z przemysłu tłuszczowego charakteryzującego się bardzo dużą zawartością substancji tłuszczowych (57%) oraz wynikającą stąd mazistą konsystencją. Proces kompostowania prowadzono w warunkach tlenowych metodą pryzmową w trzech niezależnie, jednocześnie przygotowanych stosach kompostowych. Warunkiem skuteczności prowadzonego procesu było polepszenie właściwości fizycznych wyżej wspomnianego odpadu poprzez dobranie odpowiedniego materiału strukturotwórczego stwarzającego warunki tlenowe dla prawidłowego funkcjonowania mikroorganizmów odpowiedzialnych za rozkład substancji tłuszczowych. Istotne znaczenie w przeprowadzonych badaniach odegrało ustalenie odpowiedniej wilgotności pryzm kompostowych na początku procesu (w zakresie 60–75%) w celu zapewnienia odpowiedniej aktywności wodnej dla rozwoju mikroorganizmów i zainicjowania wytwarzania metabolitów przez bakterie mezofilne, które ulegając utlenieniu zainicjowały wytworzenie dużej ilości ciepła, a tym samym gwałtowny wzrost temperatury w pryzmach już w trzeciej dobie do 40°C, a następnie osiągnięcie temperatury maksymalnej (60°C) w dwunastej dobie i utrzymywanie się zakresu temperaturowego 50–57°C przez kolejne 15 dni. Ustalone optymalne wilgotności i proporcje materiałów do skomponowania stosów kompostowych przyczyniły się do ustalenia również właściwego pH wewnątrz stosów kompostowych w zakresie pH 6,5 do 7,5, co przy niekorzystnej wartości pH = 3 odpadu podlegającego biodegradacji czyli zaolejonej ziemi bielącej, stanowiło niebagatelny problem na początku procesu. Konsekwencją intensywnie przebiegającego procesu mineralizacji wyrażonego wzrostem temperatury były ilościowe zmiany węgla i azotu ogólnego prowadzące z kolei do systematycznego zmniejszania się wartości stosunku C:N z 29:1 do 15:1 po 6 miesiącach kompostowania. W gotowym kompoście zawartość substancji tłuszczowych wynosiła 9,1 g•kg-1s.s., która to wartość nie obniża wartości nawozowej uzyskanego kompostu.The aim of the study was to investigate biodegradability of fat industry
waste, characterized by very high contents of fatty substances (57%) and the resulting
greasy consistency. The composting process was run under aerobic conditions
using the compost heap method in three independent, simultaneously prepared
compost heaps. A necessary pre-condition to ensure the effectiveness of the
conducted process was to improve physical properties of the above mentioned
waste by selecting an appropriate structure-forming material, providing aerobic
conditions for the adequate functioning of microorganisms responsible for decomposition
of fatty substances. In the conducted investigations it was essential to determine
adequate moisture content of compost heaps at the beginning of the process
(ranging from 60 to 75%) in order to provide appropriate water activity for the
development of microorganisms and initiation of metabolite production by
mesophilous bacteria, which when oxidized initiated generation of large amounts
of heat, and thus a rapid increase in temperature in heaps already at the third day
to 40°C, and next reaching the maximum temperature (60°C) at day 12, and the
maintenance of the temperature range of 50–57°C for the next 15 days. Determined
optimal moisture contents and proportions of component materials for compost
heaps contributed additionally to the determination of appropriate pH inside
compost heaps to be within the range of 6.5 to 7.5, which at the adverse value
pH = 3 of the biodegradable waste, i.e. oiled fuller's earth, constituted a serious
problem at the beginning of the process. The intensive mineralization process,
manifested in an increase in temperature, resulted in quantitative changes in carbon
and total nitrogen, leading in turn to a regular decrease in the values of the
C:N ratio ration from 29:1 to 15:1 was reduced. The content of fat substances was
9,1 g·kg-1d.m in mature compost. That concentration of fat not reduce organic
value of prepared compost