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النتائج 71 - 80 من 96
The current status and future perspectives of lactobionic acid production: a review
2018
Sarenkova, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Lactobionic acid is a high value added compound industrially produced through energy intensive chemical synthesis, which uses costly metal catalysts, like gold and platinum. In the next years, biotechnological production of lactobionic acid can be supposed to take the full transition to the manufacturing stage. Productivity of lactobionic acid by microbial production can be affected by various factors – choice of microorganism and its concentration, supply of oxygen, temperature, substrate, cultivation method, pH and aeration rate. The aim was to review research findings for lactobionic acid production as well innovative and efficient technology solutions for self-costs reducing. Whey was recommended as a cheap and suitable substrate for the lactobionic acid production. Whey processing has been advised with Pseudonomas teatrolens in 28 °C and in pH 6 to 7 for yielding the highest productivity. The increasing commercial importance urges the progression of schemes for lactobionic acid biotechnological manufacturing.
اظهر المزيد [+] اقل [-]Quality of specialty coffee: balance between aroma, flavour and biologically active compound composition: review
2018
Laukaleja, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Specialty coffee, according to Specialty Coffee Association of America (SCAA) standards, is coffee which has been standardized from the coffee plantation process until its delivery to the consumer, in compliance with all quality standards, to highlight the characteristics of the beverage. With increasing coffee consumption, more attention is focused not only on the flavour and texture of the drink, but also on the impact of coffee on health. The beneficial effects of coffee on human health are mainly based on a wide range of biologically active components. The coffee composition of the biologically active compounds and flavour compounds are influenced differently by almost all technological processes. The aim of this review was to summarize recent scientific developments about composition of aroma, flavour and biologically active compounds in specialty coffee and evaluate the best possibilities to balance health promoting and flavour attributes. Specialty coffee mainly focuses on fruity, floral, sweet and acidic notes in coffee, which are opposite to phenolic compound aroma characteristics during roasting process. In conclusion, roasting temperature significantly influences all biologically active compounds and important aroma, flavour volatiles in coffee. All compound concentration, except coffee melanoidins, decreases during roasting process. Light-medium roast level could provide stability among floral, fruity aroma, flavour notes and biologically active compounds (phenolic compounds and coffee melanoidins) in coffee.
اظهر المزيد [+] اقل [-]Radiodensity of medial coronoid process in dogs
2018
Veksins, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Kozinda, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of this study was to detect radiodensity of a medial coronoid process of elbow joints with a medial coronoid disease and normal elbow joints in dogs. The study includes 91 large and giant breed dogs at the age from 6 to 30 months. Medial coronoid disease was diagnosed in 65 dogs and 26 dogs had normal elbow joints. Computed tomography was performed with Philips MX – 16 CT scanner and imaging data analysis performed using Horos v.2.2.0 software. CT technical data included 140 kVp, 250 mAs, 1 second rotation time and 0.75 slice thickness. The density of a medial coronoid process (MCP) was measured by two unrelated measurement methods. The study describes Hounsfield unit values in different areas of MCP in normal elbow joints and in medial coronoid disease affected joints. In 91.8% cases, MCP subchondral sclerosis observed with MCP fragmentation or fissure. We conclude that both bone density measurement methods are suitable for veterinary diagnostic imaging and can be used to evaluate canine elbow joints.
اظهر المزيد [+] اقل [-]Impact of inulin on production of methane, carbon dioxide and gastrointestinal canal functionality in calves
2018
Jonova, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Ilgaza, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)) | Grinfelde, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zolovs, M., Daugavpils Univ. (Latvia)
Ruminants produce a large amount of methane (CH4 ) and carbon dioxide (CO2 ) in their foregut. These gases cause greenhouse effect. There are a lot of studies about different feed additives which can reduce the production of greenhouse gases in ruminants. Prebiotics can also change the amount of bacteria in animal gastrointestinal tract and reduce the occurrence of diarrhoea. The aim of this study was to test whether the prebiotic inulin affects the production of CH4 and CO2 in calves’ rumen and whether it affects the bacteria count in the rumen fluid and bacterial overgrowth in intestines. We used the flour of Jerusalem artichoke (Helianthus tuberosus L.) containing 50% of inulin. Approximately fifty days old, Holstein Friesian crossbreed calves were used in this study. Eight were in the control group, 8 received 12 g of flour and 8 received 24 g per day. On the 28th and 56th day of the research, we measured the amount of CH4 and CO2 in calves’ rumen took rumen fluid samples for bacterial analysis and urine to measure the level of phenol and indican. We concluded that adding the flour of Jerusalem artichoke at doses 12 g and 24 g did not significantly impact the production of CH4 and CO2 in calves’ rumen, the prebiotic inulin may suppress the growth of anaerobic microorganisms in the rumen at concentration 12 g of inulin reaching 56th day of experiment. The amount of phenol and indican in calves’ morning urine did not correlate with the faecal consistency of calves.
اظهر المزيد [+] اقل [-]Assessment of the immunogenicity and protective effectiveness of Refluvac® in mice challenged with a pandemic A/H1N1 influenza
2018
Nurpeisova, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Kassenov, M., Research Inst. for Biological Safety Problems, Gvardeyskiy settlement, Zhambyl Oblast(Kazakhstan) | Makbuz, A., Kazakh National Agrarian Univ., Almaty (Kazakhstan) | Sansyzbay, A., Research Inst. for Biological Safety Problems, Gvardeyskiy settlement, Zhambyl Oblast(Kazakhstan) | Valdovska, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Khairullin, B., Research Inst. for Biological Safety Problems, Gvardeyskiy settlement, Zhambyl Oblast(Kazakhstan)
This article describes the results of a pre-clinical study of immunogenicity and effectiveness of an inactivated pandemic vaccine (Refluvac®) on model mice. Mice received two 0.5 ml intraperitoneal inoculations with an interval of 14 days in three doses: containing 10.0, 5.0 and 2.5 μg HA (hemagglutinin) per animal. As a comparator preparation, the study used a semi-finished product (SP) vaccine diluted with phosphate buffered saline (PBS) to obtain HA concentrations of 5 μg and 10 μg. For a control group, the study used PBS as the negative control. We determined the vaccine’s protective effectiveness level by analysing its response in animals challenged with a pandemic А/California/7/09 (Н1N1) pdm09 virus. We assessed the immunogenicity of the vaccine by examining the mean geometric titre (GMT) of antibodies against the influenza virus as measured by hemagglutination-inhibition test (HAI). In the course of testing the GMT, we noted a dependence of the concentration of antibodies in serum on the vaccine’s antigen load. The highest GMT was observed in the group of mice vaccinated with a HA load of 10.0 μg – it amounted to 278.6 (95% CI, 135.6 to 572.4). We established a high tolerability of the vaccine tested. Our study shows that Refluvac® yields a high degree of protectivity against influenza A/H1N1 and prevents clinical signs, death or accumulation of influenza virus in the organs of vaccinated animals. There were deaths and clinical signs including general depression, hypodynamia and anorexia in the negative control group. The results of our study were used for the clinical study of the first Kazakhstan produced Refluvac® vaccine against pandemic A/H1N1 influenza virus.
اظهر المزيد [+] اقل [-]Barbarea arcuata as a potentially expansive species in agricultural landscapes in Latvia
2018
Rurane, I., University of Latvia, Riga (Latvia). Botanical Garden;University of Latvia, Riga (Latvia);Daugavpils Univ. (Latvia) | Roze, I., University of Latvia, Riga (Latvia)
The distribution and abundance of Barbarea arcuata (Opiz ex J. et C. Presl) Rchb. were investigated throughout the territory of Latvia. The field survey was carried out to estimate the abundance patterns, and the herbarium materials were used to compile a distribution map. In total 411 localities were recorded in the period from 2015 to 2017. The species has been commonly found on roadsides, which accounts for 66% of the localities. Seventeen percent of the localities occurred in grasslands, 10% – in croplands, 4% – in fallows, 2% – on road embankment slopes, and 1% – on railway embankments. The highest density of B. arcuata were found in new fallows where it forms large populations. Whole field localities account for 5% of the total localities. Medium-sized stands are found in about 20% of localities and are mostly found in grasslands, roadsides, as well as croplands which include cereal fields and oilseed rape fields. Individual specimens are mostly found on roadside habitats and grasslands and account for 75% of the total number of localities. As dominant weed species it is found on fields of oilseed rape, cereal fields and fallows. Herbarium data and the Institute of Biology, University of Latvia lists of species show that B. arcuata distribution was frequent during the period from 1970 to 2014.
اظهر المزيد [+] اقل [-]Productivity of crop rotation measured as energy produced by included plants: a review
2018
Darguza, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Gaile, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The most important reason for growing field crops is food consumption. Only some of the total amounts of field crop species are mostly used for cultivation in the largest part of arable land. These crops ensure high economic income. This is the reason why biological diversity has decreased. Crop rotation is considered to be an instrument of sustainable cropping system and this is confirmed again nowadays. Higher cereal yields have been gained by including oil crops or pulses in the rotation. Each field crop has its own calorific value (MJ kgE-1). Grains/seeds and above-ground biomass may have different calorific values because of their chemical composition. Research results from literature confirm that the average net calorific value of winter wheat (Triticum aestivum) and triticale (Triticosecale) grain and straw are ~17 MJ kgE-1, but the net calorific values for oilseed rape (Brassica napus ssp. oleifera) seeds and straw are – 25.70 MJ kgE-1 and 16.37 MJ kgE-1, respectively. Oilseed rape is also known as energy rich crop. It is reported that diversified crop rotations also have greater energetic productivity from above-ground biomass (grain/seed yield and by-products) if compared with crops grown in repeated sowings or in monoculture. Crop rotation in combination with different tillage methods (conventional tillage, reduced or minimum tillage and no-tillage) is the way to improve soil quality, but it is not clear whether the soil treatment method has a significant impact on the overall crop rotational energy productivity.
اظهر المزيد [+] اقل [-]The influence of production technology on yield and selected quality parameters of spring wheat cultivars
2018
Sulek, A., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Cacak-Pietrzak, G., Warsaw Univ. of Life Sciences (Poland)
The field experiments were conducted at the Institute of Soil Science and Plant Cultivation – State Research Institute Experimental Station in Osiny in the years of 2015 – 2016. The aim of the study was to compare spring wheat (Triticum aestivum L.) yield depending on an integrated and intensive technology. The used production technologies differed as regards the nitrogen fertilization level, chemical protection against weeds, diseases, pests and the way of straw utilization. The following cultivars were selected for the research: ‘Arabella’ and ‘KWS Torridon’. The weather conditions differentiated the yield of spring wheat in individual years. A higher effectiveness of intensive technology, expressed with a higher grain yield compared to the integrated one, was recorded in 2015 – on average by 18.0%. The yield increase between intensive and integrated technologies resulted from a higher 1000 grain weight. Spring wheat cultivars showed a varied response to the production technologies used. Under the intensive technology, a significant yield increase was recorded for the cv. ‘KWS Torridon’, while the production technologies did not differentiate the yield of cv. ‘Arabella’. The quantity and quality of protein substances and the activity of amylolitic enzymes in grains were more dependent on the cultivar than on the production technique used. In the case of spring wheat cultivars ‘Arabella’ and ‘KWS Torridon’, the integrated production technology ensures obtaining grains of the quality suitable for processing.
اظهر المزيد [+] اقل [-]Response of barley on seaweed biostimulant application
2018
Szczepanek, M., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Jaskiewicz, B., Institute of Soil Science and Plant Cultivation – State Research Inst., Pulawy (Poland) | Kotwica, K., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
In some regions of the world, there is a risk of limiting crop production due to the growing pressure of biotic and abiotic factors. It is mostly connected with the forecasted climatic changes. Hence, alternative methods for supporting plant growth are sought for, and among them, biostimulants can play a significant role. The three-year (2009 – 2011) field experiment with spring barley (Hordeum vulgare L.) was conducted in Poland to assess the response of grain yield, yield components, as well as the content and uptake of N, P and K in grain to differentiated times and to a dose of seaweed (Ecklonia maxima Osbeck) biostimulant Kelpak application. Preparation was applied in a dose of 2 L haE-1 at BBCH 22 (early treatment) or in a dose of 2 L haE-1 at BBCH 31 (late treatment), as well as two times, 1.5 L haE-1 each, in both phases. The study indicated that the biostimulant had a favourable effect on the root weight, grain number per spike, thousand grain weight and seed yield in early treatment as compared with the control. Early application also had a positive effect on N and P uptake in the grain yield. Favourable response of barley to the application of biostimulant shows the usefulness of the seaweed extract in the cultivation technology of this crop.
اظهر المزيد [+] اقل [-]Forecasting production effects of irrigated faba bean (Vicia faba var. minor) depending on drought levels
2018
Dudek, S., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Kusmierek-Tomaszewska, R., UTP Univ. of Science and Technology, Bydgoszcz (Poland) | Zarski, J., UTP Univ. of Science and Technology, Bydgoszcz (Poland)
The aim of the article was to develop formulas, which can be used to model forecasts of production and economic effects of irrigated faba bean (Vicia faba var. minor), depending on drought severity level in a growing season. For the analysis we used data of ten-year (2005 – 2014) production effects of irrigated faba bean and indices calculated on the basis of meteorological data from the measuring point set in the vicinity of the experimental site in region of Bydgoszcz city, central Poland. Based on them, the most relevant relationships between irrigation productivity and chosen drought indices, calculated for a period of high water needs of the plant, were searched. Presented results have demonstrated that the non-irrigated faba bean yields depended significantly on drought severity level and showed very high variability in time. Irrigation contributed to a significant 49% increase in yields and their stability in the years. Due to this treatment, the coefficient of variation of the yield decreased from 55.1 to 19.6%. The production effects of irrigation depended significantly on moisture conditions over the period of high water needs of faba bean. In wet seasons, the increases in yields due to irrigation were insignificant and about three-fold lower, while in the dry periods – more than a half higher (57%) than the average increases. The results presented in the work are of great importance because they can be used to model forecasts of production, as well as to plan the development of irrigation systems in the given area.
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