Search results for "rasvahapot"
showing 10 items of 56 documents
Biochemical profiling of temperate zone freshwater green microalgae grown in filtered and unfiltered recirculating aquaculture systems effluent and m…
2020
Viljelemällä mikroleviä kalojen kiertovesiviljelyn jätevedessä siitä voidaan poistaa ravinteita ja tuottaa niistä biomassaa. Menetelmää voidaan käyttää korvaamaan perinteistä jäteveden käsittelyä ja kehittämään vesiviljelyn kannattavuutta. Tässä työssä verrattiin kolmen eri viherlevälajin (Haematococcus pluvialis, Monoraphidium griffithii and Selenastrum sp.) kasvua, ravinteiden poistoa, sekä rasvahappo- ja aminohappoprofiileja, kun leviä kasvatettiin suodatetussa tai suodattamattomassa kiertovedessä tai levien elatusaineessa. Monoraphidium ja Selenastrum -lajien kasvunopeudet olivat pienemmät kiertovedessä (0.64 vrk-1 ja 0.50 vrk-1) kuin levien elatusaineessa (0.72 ja 0.59 vrk-1), mutta Ha…
The metabolic responses to electrical pulse-induced contractions in C2C12 myotubes are greater in high glucose medium
2021
Osaa liikunnan terveyshyötyjen mekanismeista on vaikeaa tutkia ihmisillä tai koe-eläimillä. Viljeltyjen C2C12 myotuubien sähköpulssistimulaatiolla (EPS, engl. electrical pulse stimulation) voidaan mallintaa lihassupistuksia ja liikuntaa in vitro –olosuhteissa. EPS:n vaikutusta C2C12 myotuubien aineenvaihduntaan ei kuitenkaan tunneta tarkasti. Lisäksi C2C12 myotuubeja viljellään yleensä korkeassa ei-fysiologisessa 25 mM glukoosipitoisuudessa, mikä voi vaikuttaa EPS-vasteisiin. Tässä tutkimuksessa C2C12 myotuubeja sähköpulssistimuloitiin 24 tunnin ajan sekä matalan 5.5 mM (MG) että korkean 25 mM (KG) glukoosipitoisuuden olosuhteissa, ja aineenvaihduntatuotteiden konsentraatiot analysoitiin se…
Effects of progressive decrease of feeding frequency and re-feeding on production parameters, stomach capacity and muscle nutritional value in rainbo…
2020
Feeds and feeding constitute the major part of costs in intensive aquaculture. Any action to reduce feeding costs without negatively affecting fish production parameters and flesh quality would improve profitability of farming. Therefore, we studied the effects of feeding frequency on production parameters, stomach capacity and nutritional value of muscle in juvenile rainbow trout (Oncorhynchus mykiss) in an experiment with two stages. First, during the nine-week “starvation period” we fed rainbow trout (initial weight c. 40 g) with four different feeding protocols in an attempt to adapt the fish to a progressive decrease in the number of feeding days. During the second stage, a four-week “…
The second life of terrestrial and plastic carbon as nutritionally valuable food for aquatic consumers
2023
Primary production is the basis for energy and biomolecule flow in food webs. Nutritional importance of terrestrial and plastic carbon via mixotrophic algae to upper trophic level is poorly studied. We explored this question by analysing the contribution of osmo- and phagomixotrophic species in boreal lakes and used 13C-labelled materials and compound-specific isotopes to determine biochemical fate of carbon backbone of leaves, lignin–hemicellulose and polystyrene at four-trophic level experiment. Microbes prepared similar amounts of amino acids from leaves and lignin, but four times more membrane lipids from lignin than leaves, and much less from polystyrene. Mixotrophic algae (Cryptomonas…
Differing Daphnia magna assimilation efficiencies for terrestrial, bacterial, and algal carbon and fatty acids
2014
There is considerable interest in the pathways by which carbon and growthlimiting elemental and biochemical nutrients are supplied to upper trophic levels. Fatty acids and sterols are among the most important molecules transferred across the plant–animal interface of food webs. In lake ecosystems, in addition to phytoplankton, bacteria and terrestrial organic matter are potential trophic resources for zooplankton, especially in those receiving high terrestrial organic matter inputs. We therefore tested carbon, nitrogen, and fatty acid assimilation by the crustacean Daphnia magna when consuming these resources. We fed Daphnia with monospecific diets of high-quality (Cryptomonas marssonii) an…
Novel concepts on the recovery of by-products from alkaline pulping
2016
Innovative biorefinery concepts were developed for the separation and utilization of organic materials, especially aliphatic carboxylic acids, lignin, and extractives, which are formed as by-products during wood-based alkaline delignification processes. The partial recovery of sodium as NaOH and aliphatic carboxylic acids from hardwood soda-AQ black liquor was studied via electrodialysis. The lignin was partly (about 59 % of the initial lignin) precipitated from black liquor by carbonation (pH to about 8.5) followed by electrodialysis or H2SO4 (pH to about 2), with subsequent precipitation of more lignin and the liberation of aliphatic acids. The Na2SO4 formed was successfully separated fro…
Temperature, phosphorus and species composition will all influence phytoplankton production and content of polyunsaturated fatty acids
2023
Temperature increases driven by climate change are expected to decrease the availability of polyunsaturated fatty acids in lakes worldwide. Nevertheless, a comprehensive understanding of the joint effects of lake trophic status, nutrient dynamics and warming on the availability of these biomolecules is lacking. Here, we conducted a laboratory experiment to study how warming (18–23°C) interacts with phosphorus (0.65–2.58 μM) to affect phytoplankton growth and their production of polyunsaturated fatty acids. We included 10 species belonging to the groups diatoms, golden algae, cyanobacteria, green algae, cryptophytes and dinoflagellates. Our results show that both temperature and phosphorus w…
Associations of dietary carbohydrate and fatty acid intakes with cognition among children
2020
Objective: To investigate the cross-sectional associations of dietary carbohydrate and fatty acid intakes with cognition in mid-childhood. Design: Dietary carbohydrate and fatty acid intakes were assessed using 4-d food records, and cognition was evaluated using the Raven’s Coloured Progressive Matrices (RCPM) score. The cross-sectional associations of dietary carbohydrate and fatty acid intakes with cognition were investigated using linear regression analyses adjusted for age, sex, body fat percentage, household income, parental education and daily energy intake. Setting: The baseline examinations of the Physical Activity and Nutrition in Children study. Participants: A population-based sa…
Simulated eutrophication and browning alters zooplankton nutritional quality and determines juvenile fish growth and survival
2018
Source at https://doi.org/10.1002/ece3.3832. The first few months of life is the most vulnerable period for fish and their optimal hatching time with zooplankton prey is favored by natural selection. Traditionally, however, prey abundance (i.e., zooplankton density) has been considered important, whereas prey nutritional composition has been largely neglected in natural settings. High‐quality zooplankton, rich in both essential amino acids (EAAs) and fatty acids (FAs), are required as starting prey to initiate development and fast juvenile growth. Prey quality is dependent on environmental conditions, and, for example, eutrophication and browning are two major factors defining primary produ…
Microwave-Assisted Esterification of Tall Oil Fatty Acids with Methanol Using Lignin-Based Solid Catalyst
2016
During alkaline pulping significant amounts of lignin, carbohydrates (mostly hemicelluloses), and extractives (tall oil soap and turpentine) are removed from wood feedstock. In this study, the catalytic esterification of fatty acids in tall oil with methanol to produce fatty acid methyl esters under microwave irradiation was performed at 100 °C for 10–60 min. A novel heterogeneous acid catalyst tested for this purpose was synthesized from the hardwood alkali lignin that was precipitated by acidification from the black liquor from soda-AQ pulping. The comparative reaction data were obtained by using other solid catalysts, Amberlyst 15, and p-toluenesulfonic acid. The results showed the highe…