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Determination of conversion rate values to characterise the ethanol production of the Kluyveromyces marxianus CBS712 fungus branch
Published December 22, 2010

The ethanol production of the Kluyveromyces marxianus CBS712 strain was investigated among different kind of condition. We defined the conversion rate in order to know the efficiency of the ethanol production. To determine this value, it is crucial to characterize the residual glucose concentracio. We chose two method to determine the amount of... residual glucose. The first method is the thin layer chromatography (TLC) and the second method is the method of the glucose-oxidase enzyme. We found that the TLC method is reliable than the other method. The conversion rates were determined from these values and the ethanol values. The maximal ethanol production of the characterized Kluyveromyces marxianus CBS712 strain (5.6% (v/v) ethanol at 45 °C, 55.3% conversion rate) is comparable to those strains which are applied in industrial ethanol production nowadays.

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Characterisation of a thermotolerant yeast, Kluyveromyces marxianus CBS712
Published October 20, 2009

Fermentation at high temperature with application of thermotolerant microorganisms is a technological advantage in bioethanol production. Among the yeasts, K. marxianus has outstanding thermotolarance. The industrial application of the IMB3 strain occurs usually at 45C. The final aim of our project is the genetic modification of the K. marxianu...s CBS712 strain in order to achieve ethanol production at higher temperature than the currently applied. This requires the characterization of the CBS712 strain, with special attention to the determination of the temperature limit of its growth and the amount of the ethanol produced. The temperature limit of growth was 48C in YPD medium. Elevation of the temperature above 45C led to an exponential drop of the cell viability. Ethanol production was tested in shaking flasks, in MYFM medium, under oxigene limited conditions, applying variable concentrations of glucose (12–20%) and different temperatures (45–47 ºC). Preliminary results have revealed that the elevation of glucose concentration increased the amount of ethanol produced. The amount of ethanol (appr. 5%)+ produced at the highest glucose concentration was not different at the tested temperatures (45, 46 and 47 ºC). The observation indicates the potential in raising the thermotolerance of the strain. 

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Evaluation of sweet sorghum and sudangrass varieties by the viewpoint of bioethanol production
Published April 23, 2014

Bioenergy and biofuels are very important in today’s energy policy. These kinds of energy resources have several advantages against fossil fuels. Environmental protection is a cardinal point of widespreading these technologies but the economic considerations are important as well. In order to improve the rate of the renewable energy in the en...ergy consumption, the European Union settled down a program which determines a minimum ratio of renewable energy in the energy consumption for each member country of the EU. To fulfil the requirements bioenergy and biofuels should be produced. This production procedure needs adequate stocks which are commonly agricultural products.
One of the promising stocks is sorghum. This plant fits for bioethanol production due to its juice content being rich in sugar. In this study six sweet sorghum hybrids, two sudangrass hybrids and a sudangrass variety have been evaluated to determine their theorical ethanol production capacity.
On the score of the results of the year 2009 it can be set that sudangrasses have a lower theorical ethanol capacity than sweet sorghums have. In the case of sweet sorghums 1860.29–2615.47 l ha-1 ethanol yields had been calculated, while the sudangrasses had only 622.96–801.03 l ha-1. After that throughout three years (2011–2013) the sweet sorghum hybrids have been evaluated in order to determine the fluctuations of the ethanol production capacity caused by the impact of the years. As a result 2425.44–4043.6 l ha-1 theorical ethanol capacities have been calculated, which means that sweet sorghums can be an adequate stock to produce bioethanol.

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Economic issues of crop based ethanol production for energetic uses
Published September 7, 2001

The United States Congress passed the “Clean Air Act” in 1990, which targeted the creation and use of so-called “green fuel”. This Act came into full force on January 7, 1995. Its essence is that an oxygen rich component is added to fuel by which it burns more cleanly and harmful emissions of vehicles are reduced by 25%. This oxygen ric...h component is basically ethanol and its ether ETBE, made of domestically produced grains.
America’s traditional grain exporter status could be converted into a stabile income resource during production, many more valuable by-products – should this program succeed – are also produced, giving the opportunity for further utilisation either in the foods or form feeds industries, or as export products.
Ethanol or ETBE production is also important to replace fuel imports from any specific country, the additive which is necessary for producing the fuel is the imported product MTBE.
This programme therefore simultaneously assisted in environmental protection, agricultural and foreign trading issues as well as some market regulation issues. At the same time, based on grain production, it has an effect on the social strata by creating new jobs, especially in those areas which can be considered in recession due to the lack of any large-scale industrial cities.
In the future, the European Union should carry out this project and it will affect Hungary, as well.

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Development opportunities of biomass-based ethanol production in relation to starch- and cellulosebased bioethanol production
Published February 10, 2013

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The biomass is such a row material that is available in large quantities and it can be utilizied by the biotechnology in the future. Nowadays the technology which can process ligno cellulose and break down into fermentable sugars is being researched. One possible field of use of biomass is the liquid fuel production such as ethanol production. Based on the literary life cycle analysis, I compared the starch-based (first generation) to cellulose-based (second generation) bioethanol production in my study considering into account various environmental factors (land use, raw material production, energy balance). After my examination I came to the conclusion that the use of bioethanol, independent of its production technology, is favorable from environmental point of view but the application of second generation bioethanol has greater environmentally benefits.

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The effect of the preparation method on the physical and chemical characteristics of propolis tinctures
Published June 30, 2018

The effect of the preparation method was examined with regards to the physical and chemical characteristics of the propolis tincture, namely the extraction time and the ethanol content of the extraction solvent to the dry matter, polyphenol, flavonoid, phosphorus, calcium and copper concentration, respectively. The dry matter, the polyphenol an...d the flavonoid content were the lowest in the water extract of the propolis; however, significant increase was noticed depending on the extraction time. Significantly higher concentrations were found in 50 V/V% tinctures. The highest dry matter and flavonoid contents were analysed in 100 V/V% tinctures, whereas highest polyphenol content was found in 80 V/V% tinctures. However, the differences were not significant in several cases between latter tinctures. Moreover, the increase was not determined in some cases depending on the extraction time. Phosphorus and calcium concentrations were decreased depending on the increasing ethanol content, whereas copper concentration was increased up to 80 V/V%. Higher increase was found in the case of 0 and 50 V/V% extracts than in 80 and 100 V/V% tinctures. Moreover, in latter cases, no significant differences were found on several occasions, depending on the extraction time. There was no connection between the flavonoids and the calcium as well as the phosphorus content, whereas flavonoids may be made complex with copper. However, the amount of the possible complex was negligible.

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Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
Published May 23, 2019

Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication sympt...oms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.

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Detailed specification of the steps of dry milling ethanol production
Published February 10, 2013

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">Durring the 2011 year I was given the possibilty to study in Indiana, USA for 5 months with the help of the Bloomington fellowship, and had the chance to study the bioethanol production in the given state. I focused mainly on the details of corn based dry milling large scale bioethanol production. The dry milling process is a relatively common production mode in the USA. In the coure of my research I tried to compare and to highlite the advantages of the dry milling process contrasted with the wet milling bioethanol production.

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Nutrient Uptake of Miscanthus in vitro Cultures
Published May 12, 2002

The large biomass production and the low necessary input fertilizer make Miscanthus an interesting, potential non-food crop with broad applications, e.g. for fuel and energy, for thatching, fiber production, for the paper and car industries, as well as for ethanol production.
Axillary buds of Miscanthus x giganteus were placed on a shoot ind...ucing nutrient solution (modified Murashige and Skoog, 1962), basic medium supplemented with 0,3 mg l-1 6-Benzylaminopurin. After 40 days of culturing, the axillary buds produced three times more shoots than could normally be harvested. The nutrient content (N, P, K, Ca, Mg) was measured several times during culturing. The results showed that, after 35 days, nitrogen and phosphate were nearly completely taken up. From that time, shoot growth was not observed.
After shoot propagation, the plants were transfered into a nutrient solution for root formation (modified Murashige and Skoog, 1962), basic medium supplemented with 0,5 mg l-1 Indole- 3-Butyric acid, and could be potted in soil after about 14 days.

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Evaluation of various silo sorghum hybrids from the energetic aspect
Published February 10, 2013

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The sweet sorghum is a perspective plant of bioenergy, which can be the foundation of Hungarian bioethanol production in the future. By the examination six sweet sorghum hybrids have been examinated by the viewpoint of sugar aggregation and bioethanol production capacity. The founda tion of the surve y was three growing se ason (201 0, 2011, 2012 ). The ex per ime nt w as on the production sites of U niversity of Debrecen CAAES RISF Karcag Research Institute. The production site of the sweet sorghum have been sampled by samples of 1 m2 by hybrids within the period of august 15 and november 15. The sugar content of the samples have been measured by refractometer which was the base in the determination of ethanol production capacity.

As a continuation of the evaluation of energetic viewpoint the Higher Heating Value (HHV) have been measured from the bagasse of sweet sorghums. According to the results it can be stated that int he case of sugarcontent and the dinamics of the sugar aggregation can show several differences, while HHV of sorghum bagasse is within 16 200 and 16 900 J g-1.

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Evalution of energy for bioethanol production
Published February 10, 2013

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The objective of this study was the ethanol which classified as agro fuels. The aim of our research was the calculation of efficiency of bioethanol production, and evaluates the yield of maize hybrids grown for this purpose. We examined the energy demand of corn production per hectare in two vintages of 2009 and 2010. The focus of the experiment was placed in three different doze of fertilizer. Results show that the control corn plot used the least amount of non-renewable energy. Improving starch yield by adding fertilizer required additional nonrenewable energy inputs. So then the invested energy has a great impact on the efficiency.

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Energy production systems of phototroph microorganisms (classification of photobioreactors)
Published December 22, 2010

In the field of alternative energy sources there is an argue in the comparison of its effects on the benefits and disadvantages to the economics and the environment. New studies are born which are in contradiction with each other. The demand for bioenergy feedstock is growing rapidly however there are the environmental problems caused by the ex...tending energy crop plantations. There is such a significant need for land to grow traditional energy crops on (rape, soy, palm-oil, sugarcane, etc.) that the food purpose agricultural capacity could be in danger. Probably the extensively
growing energy crops play a role in the very high prices of food. In some countries like China for example laws prohibit the use of food based crops such as corn for energie production. In the case of corn based ethanol production the cost only for the feedstock itself is over 60% of the whole preparation costs which significantly effects the entire economy of the energy productions process.
The microalgaes however have a huge biotechnological potential and their production is notably cheaper then the traditionaly grown food crops growing expenses. They play a significant role as feedstocks in todays industrial production in such fields as comestible production, cosmetics, pharmaceutics and biotechnology especially in biofule production. In the field of economy the major aspects here are also the technological designs
and the construction. For the future industrial production the closed type systems seem to have more advantages compared to the open, pond-type systems. For high value material production the more innovative and more easily developed closed photobioreactors are the profitable regardless the vast techological designs used in the construction. 

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The Carpathian lingonberry, raspberry and blackberry fruit extracts feature variable antimicrobial efficiency
Published May 23, 2019

Wild berry is an excellent source of phytonutrients and/or bioactive compounds associated with significant therapeutic properties, so that they have been utilized in folk medicine and traditional nutrition throughout centuries. Multiple health-promoting effects, such as anti-inflammatory, anti-diabetic, anti-heart and coronary disease propertie...s were attributed to such wild berries. It has also been proved that berries could feature antimicrobial effects that could be of a great importance for the prevention of food-feed poisoning and fighting back antibiotic resistance.

In this study, we investigated the antimicrobial properties of lingonberry (Vaccinium vitis-idaea), raspberry (Rubus idaeus) and blackberry (Rubus fruticosus) crude and ethanolic extracts prepared from fruits obtained from the spontaneous flora of Eastern Carpathian Mountains situated in Transylvania. The antimicrobial effect of crude and alcoholic extracts were assessed on four Gram-negative, five Gram-positive bacteria and one yeast species using the agar diffusion method. The studied bacteria can cause food or feed spoilage and foodborne diseases. Our results indicate the significant inhibitory effect of lingonberry extracts in the case of Gram-negative bacteria like Proteus vulgaris and Salmonella Hartford, while among Gram-positive bacteria the strongest inhibitory effect was observed for Bacillus species like B. cereus, B. subtilis, B. mojavensis and Micrococcus luteus. The raspberry and blackberry extracts featured milder inhibitory effects in the case of the studied bacteria species. Furthermore, we have studied the crude or ethanolic extract combinations associated antimicrobial effects synergistic/additive or antagonistic properties. Interestingly, the triple and double ethanolic extract mixes had stronger antimicrobial properties, whereas the crude extract mixes showed relatively reduced effects, if any. Our results indicate that the antimicrobial activity of studied fruit extracts obtained from wild berries can vary upon the applied extraction method and their combination formulae, so that all these considerations must be taken into account when such fruit extracts are considered for foodstuff development.

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