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Stolarzewicz I.A.,Katedra Chemii | Ciekot J.,Miedzywydzialowe Studium Biotechnologii | Fabiszewska A.U.,Katedra Chemii | Bialecka-Florjanczyk E.,Katedra Chemii
Postepy Higieny i Medycyny Doswiadczalnej | Year: 2013

In recent years there has been growing interest in substances with antioxidative properties, which reduce or prevent harmful effects of free radicals on living tissues, and inhibit aging processes and the development of certain diseases. The objective of this paper is to review new methods of obtaining antioxidants of plant origin and new trends in research aiming to improve their quality and profitability on an industrial scale. Among the issues discussed, there are the methods that use techniques of plant and microbial genetic engineering. A brief description of antioxidants and natural sources of their occurrence is also presented in this paper. In view of the fact that the biosynthesis of flavonoids and isoflavonoids is probably the best-known metabolic pathway of natural plant products, the review of achievements of recent years in the field of metabolic engineering was shown with the example of flavonoids. The modifications of flavonoid biosynthetic pathways were related to changes in the expression level of structural or regulatory genes, silencing of competitive genes or modifying catalytic properties of enzymes using techniques of protein engineering. The paper also presents the achievements of microorganism engineering in the field of application of fermentation processes as a source of specific flavonoid compounds, which was possible by designing the phenylpropanoid biosynthetic pathway in cells of microorganisms such as the bacterium E. coli or S. cerevisiae, baker's yeast. Both approaches can be used in the production of flavonoids attractive in terms of application.


PubMed | Miedzywydzialowe Studium Biotechnologii and Katedra Chemii
Type: | Journal: Postepy higieny i medycyny doswiadczalnej (Online) | Year: 2013

In recent years there has been growing interest in substances with antioxidative properties, which reduce or prevent harmful effects of free radicals on living tissues, and inhibit aging processes and the development of certain diseases. The objective of this paper is to review new methods of obtaining antioxidants of plant origin and new trends in research aiming to improve their quality and profitability on an industrial scale. Among the issues discussed, there are the methods that use techniques of plant and microbial genetic engineering. A brief description of antioxidants and natural sources of their occurrence is also presented in this paper. In view of the fact that the biosynthesis of flavonoids and isoflavonoids is probably the best-known metabolic pathway of natural plant products, the review of achievements of recent years in the field of metabolic engineering was shown with the example of flavonoids. The modifications of flavonoid biosynthetic pathways were related to changes in the expression level of structural or regulatory genes, silencing of competitive genes or modifying catalytic properties of enzymes using techniques of protein engineering. The paper also presents the achievements of microorganism engineering in the field of application of fermentation processes as a source of specific flavonoid compounds, which was possible by designing the phenylpropanoid biosynthetic pathway in cells of microorganisms such as the bacterium E. coli or S. cerevisiae, bakers yeast. Both approaches can be used in the production of flavonoids attractive in terms of application.


Stolarzewicz I.,Katedra Chemii | Kapturowska A.,Katedra Chemii | Bialecka-Florjanczyk E.,Katedra Chemii
Postepy Mikrobiologii | Year: 2012

Recent years have brought intensive discussions concerning harmful influence of synthetic colorants used in food industry. It has focused the interest of both the food producers and the consumers on natural dyes. The aim of this review is to present novel methods of biosynthesis of natural colorants. The scope of the paper is not limited to those substances which are currently in use, but includes also some other compounds potentially useful in such applications are described. New sources of food colorants has been discovered among such organisms as algae (Dunaliella producing β-carotene), fungi (poliketides pigments), yeast (Ashbya gossypii producing riboflavin), bacteria. The highest expectations are connected with carotenoids, which are currently being intensively investigated. Their structural diversity opens up a wide range of potential new colorants. The most important method of their modification is cloning of crt genes and their expression in E. coli cells.


Introduction: Fungi may be present within human organism with no clinical symptoms of mycosis. Local bacterial flora and local environmental conditions in gastrointestinal tract prevent from colonization and spreading the Candida fungus. Antibiotics, namely those with a wide spectrum, cause quantitative decrease of local flora population, which disturbs proper defense mechanisms of an organism. Under such conditions, Candida fungi may reach improperly high concentrations in gastrointestinal tract gaining the ability to adherence, colonization, and dissemination. Goals and methods: Analysis of available literature references related to the influence of antibiotic therapy on gastrointestinal tract mycosis development. The poll performed among students of Lublin universities aimed at evaluating the frequency of antibiotic ingestion, conscious of respondents upon the influence of antibiotic therapy on gastrointestinal tract status, and prophylaxis application in a form of ingesting the protective drugs or diet supplements. Results: Taking antibiotics during last two years was declared by 76.1% of respondents (175 persons) and - which is particularly alarming - 32.6% (75 persons) of polled have not consulted it with any physician. Eighteen persons (7.8% of respondents) took antibiotics 4 and more times a year, while 27% (62 persons) at least once a year. Only 66% of polled (152 persons, including 72 students from University of Life Sciences - 53.7% and 80 persons from Medical University - 83.5%) applied supportive treatment during antibiotic therapy. Conclusions: Applying antibiotic therapy is a common practice at present, namely taking drugs many times within a short period and with no consultations with any physician, is particularly alarming. The clinical data related to the fact that antibiotic use may invoke problems within gastrointestinal tract, were confirmed. Supportive use of diet supplements and protective drugs that recover a proper bacterial flora within digestive tract, may be helpful. © 2011 Cornetis.


Sujka K.,Katedra Chemii | Koczon P.,Katedra Chemii | Gorska A.,Katedra Chemii | Wirkowska M.,Katedra Chemii | Reder M.,Katedra Chemii
Zywnosc. Nauka. Technologia. Jakosc/Food. Science Technology. Quality | Year: 2013

The objective of this study was the sensory and spectral assessment of spirits beverages, such as vodka, gin, whisky, and brandy that underwent a process of lyophilisation. Freezed samples of spirit beverages (-80 °C) were lyophilized in an ALPHA1-4 LDC-1m (Christ company) lyophilizator. The process parameters were constant, i.e.: pressure: 63 Pa; safety pressure: 103 Pa; time: 1.5 h. The sensory analysis was conducted using a profiling method with uni-polar category scale. Infrared spectra of freeze-dried liquid materials were registered by a transmittance method with the use of KRS crystal plates in the classic spectral range of 4000 - 370 cm-1. The spectral data were analyzed by a discriminant analysis module of the Omnic 8 software. With the process parameters applied, ethanol was the first to evaporate and, therefore, the obtained mixtures were alcohol-free. Thus, the lyophilisation process can be a gentle way to remove ethanol and water from a mixture and, at the same time, to save other important ingredients, such as dyes, flavours, or aromas.


Kozlowska M.,Katedra Chemii | Zbikowska A.,Katedra Technologii Zywnosci
Zywnosc. Nauka. Technologia. Jakosc/Food. Science Technology. Quality | Year: 2013

In a laboratory, crackers were baked with herb extracts added, their amount between 0.02 % and 0.2 % of the weight of the fat added. Also, the crackers were baked without herbs added (control sample). A sensory evaluation of the ready-baked products was performed and their colour was measured. Furthermore, oxidative changes were determined, every 7 days, in the lipid fractions extracted directly after the baking and during a 28-day period of the thermo-stating of crackers (at a temperature of 60 °C). The progress of those changes was monitored, peroxide and anisidine values were determined, and a Totox index was calculated. The addition of herbs differently impacted the sensory quality and the colour of crackers; the latter was measured using a reflectance method. The products with a 0.2 % addition of oregano extract were considered as the best. It was found that the thyme extracts provided for the most effective protection of the lipid fraction in the crackers against autooxidation processes both during the formation of the primary and the secondary oxidation products.


A review, with 17 refs., of hydrometallurgical methods for recovering Pt, Pd, Rh, Ni, Mn and V from spent catalysts.


Ionic liquids are new solvents showing unique physical-chemical properties. They are characterized by a wide range of temperatures, in which they are in a liquid form and where they exhibit high thermal stability. They are able to dissolve organic and inorganic substances as well as some polymers. They are a ‘green’ alternative to conventional solvents as their vapour pressure is very low even at a raised temperature and under a decreased pressure, and because it is possible to use them multiple times through recycling. Ionic liquids are mainly used in extraction processes from both the aqueous phase and the more complex mixtures such as food products. In many cases, the extraction from an aqueous phase consists solely in replacing an organic solvent by a ionic liquid, whereas the extraction from food samples requires that those samples are pre-treated, e.g. through etching. Ionic liquids are successfully applied to extracting metal ions, carboxylic acids, colourants, pesticides, and biologically active substances from medicinal plants. © by Polskie Towarzystwo Technologów Żywności, Kraków 2015.


Krzyczkowska J.,Katedra Chemii | Bialecka-Florjanczyk E.,Katedra Chemii
Zywnosc. Nauka. Technologia. Jakosc/Food. Science Technology. Quality | Year: 2012

Surfactants, i.e. surface active agents, are an important group of chemical compounds that are studied and applied to industry and in chemical laboratories. Presently, a tendency is observed to produce surfactants from renewable and biodegradable sources. Bio-surfactants constitute such a group; they, compared to synthetic surfactants, show a lower toxicity and a higher environmental compatibility. Bio-surfactants can be produced either using a biotransformation method or a fermentation process with the use of bacteria, yeast, or fungi. In this paper, the bio-surfactants are briefly described, the bio-technological methods of their synthesis are depicted, and, also, there are shown some selected trends in practical applications of surface active compounds.


Breastfeeding is the optimal way of feeding infants and young children. For the human infant, very important ingredients of milk are fatty acids (FA), including long-chain polyunsaturated fatty acids LC-PUFA, which are necessary for the development of human nervous system. The aim of this study was to determine the content and composition of FA in the fat of human milk in the course of lactation, taking into account the composition of FA in mothers' diet. Milk samples were obtained from 80 puerperal women hospitalized in the Obstetrics Department in Gdansk, on the 2nd, 14th, 30th and 90th day of lactation. The mothers were questionnaired about the health state and diet. Based on food frequency questionnaires the content of individual groups of FA in the daily food portions were estimated. The composition and content of FA were determined by HR-GC technique. In the studied human milk fat about 60 different FA were found. Main FA detected were: oleic, palmitic, linoleic, stearic, myristic and lauric acids. PUFA accounted on average for 13.2% of total FAs. The mean levels of trans FA in the human milk fat was 2.45% of total FAs. Percentage of each group of FA in the diet of the studied population of women averaged to 43.67, 41.74 and 14.59%, for saturated, monounsaturated and polyunsaturated FA, respectively. 1. Studies have shown that the biggest differences in fatty acid content in the human milk were observed between 2 and 14 day of lactation. 2. A positive correlation and statistically significant eff ect was observed between the composition of particular groups of FAs in human milk and the breastfeeding women's diet.

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