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Experiments were made in order to examin the influence of various factors on the induction of androgenesis in heterozygous breeding material of tomato. The factors like: length of buds the manner of sterilization, type and the composition of induction media, genotype and thermal shock were included in conducted experiments. Most of all sterile cultures with the highest number of anther-derived callus were obtain by applying 2,5% calcium hypochlorite for 5 minutes. Anther-derived calli was obtained in 9 breeding lines from 18 used genotypes. The induction medium with the composition based on B5 medium with the addition of 750 mg L-1 calcium chloride and 100 g L-1 sucrose proved to be the best for inducing androgenesis. The addition of thidiazuron and NAA to this medium in the following season and silver nitrate in the other experiminet improved the efficiency of this process, which was depended on the genotype. Despite the lack of statistically significant differences, the highest number of anther-derived calli was obtained when anthers were cooled for 2 days in +4oC in the refrigerating chamber.

The following review article brings a presentation of the published in 2018 encyclopaedia of Czech literary samizdat. The analysed publication consists of two parts – a comprehensive introduction discussing the question of independent literary culture in Czechoslovakia under communist regime pressure and an entry section with more than 300 entries about Czech independent self-publishing activities. The presentation of the following book provokes the need to re-examine the phenomenon of Czech samizdat, reflecting on its chronological framework, definition, meaning and role in creating and keeping alive an independent culture in the era of domination of the communist regime (1948–1989).

Plants can react to environmental stresses through the abscission of infected, damaged, or senescent organs. A possible mode of action of methyl jasmonate (JA-Me) to induce the formation of the secondary abscission zone (SAZ) in the stems of

Bioactive polypropylene (PP) films with active agents) presence for food packaging application have been prepared and characterized. The novel modified PP films were obtained via PP/additives systems regranulation and cast extrusion. The influence of two types of plasticizers (natural agents as well as commercial synthetic product) and bioactive additives on final features, e.g., mechanical properties, was evaluated. Moreover, the biocidal activity of the films was determined. Due to their functional properties, they are developed as additives to packaging plastic materials such as polyolefins. The study results presented in our work may indirectly contribute to environmental protection by reducing food waste. The aim of the work was to obtain innovative, functional packaging materials with an ability to prolong the shelf life of food products. The best antimicrobial properties were observed for the sample based on 5 wt.% oregano oil (OO) and 5 wt.% cedar oil (OC) in PP matrix. A microbial test revealed that the system causes total reduction in the following microorganisms: B. subtilis, E. coli, S. aureus, P. putida, C. albicans, A. alternata, F. oxysporum.

Carrot is a vegetable of increasing economic importance. New hybrid cultivars are constantly required to meet the changing market needs. The application of anther culture significantly shortens the difficult and long-lasting breeding of carrot. We examined all the stages of the process of generating androgenic plants: induction of embryos in anther cultures, regeneration and acclimatization of produced plants, their evaluation, ploidy and homozygosity, and many other factors affecting their effectiveness. Every factor has been optimized by experimentally selecting the optimal level. As a result, a full protocol of producing homozygous plants using anther cultures was developed, which is presented in this chapter.

The bacterial cellulose (BC) is a versatile biopolymer of microbial origin characterized by high purity and unusual water and material properties. However, the native BC contains a low number of functional groups, which significantly limits its further application. The main goal of its effective modification is to use methods that allow the unusual properties of BC to be retained and the desired functional group to be efficiently introduced. In the present study, the new magnetic carrier based on functionalized citric acid (CA) bacterial cellulose was developed and tested to support critical industrial enzymes such as lipase B from Candida antarctica and phospholipase A from Aspergillus oryzae. The applied method allowed BC to be effectively modified by citric acid and a sufficient number of carboxylic groups to be introduced, up to 3.6 mmol of COOH per gram of dry mass of the prepared carrier. The DSC and TGA analyses revealed carrier stability at operational temperatures in the range of 20 °C to 100 °C and substantially influenced the amount of the introduced carboxyl groups on carrier properties. Both enzymes’ immobilization significantly improves their thermal stability at 60 °C without a significant thermal and pH optima effect. The analyzed enzymes showed good operational stability with a significant residual activity after ten cycles of repeated uses. The new magnetic carrier based on highly carboxylated bacterial cellulose has a high application capability as matrix for immobilization the various enzymes of industrial interest.

The application of methyl jasmonate (JA-Me, 0.5%, w/w) as a lanolin paste to the middle of intact petiole (leaf stalk) of growing culinary rhubarb (Rheum rhabarbarum L.) induced gum formation in the entire petiole below and above the treatment. Histological analysis of petioles stained with safranin-fast green observed in light and fluorescence microscopes revealed different stages of gum duct formation. The first reaction to the JA-Me treatment was observed on the 2nd day after the JA-Me application, it being manifested by the dissolving of middle lamella in parenchymal cells. The accumulation of liquid gum in intercellular spaces of parenchymal tissue followed by the dissolution of cell walls and protoplasts leading to gum duct formation was also observed on the 5th day. Specialized secretory cells were not recognized. Some of parenchyma cells contained dense gum deposits. Gum formation in rhubarb petioles found in parenchymal tissue on the perimeter of the petioles adjacent to bark while their middle part remained intact. The general structure of the bark in rhubarb plants treated with or without JA-Me was almost similar. The more intensive safranin-staining of the cell walls in the vascular bundles was observed on the 5th and the 7th days after the JA-Me treatment. On the 7th day after the JA-Me application, gum accumulation caused rupturing of the petiole periderm followed by gum extrusion. Processes of gum exudation are discussed based on histological analyses.

Objectives: Anemia in pregnant women is a common condition, diagnosed when the concentration of hemoglobin falls below 11 g/dL. Taking into consideration the accounts of nephrologists about good results of treatment of secondary anemia using erythropoietin in patients with renal failure, we tried to use EPO to cure anemia in pregnant women. The aim of the study was to evaluate the results of EPO treatment on pregnant women diagnosed with iron deficiency anemia, as well as possible side effects. Material and methods: The study consisted of 25 patients: Group I — treated with iron supplement administered parenterally — Ferrum Lek every two days intramuscularly. Group II — treated with recombinant human erythropoietin — 1000 j intravenously every three days, with oral iron sup- plements. Results: After a week of treatment the positive response was higher in the second group (92.3% in II, vs 33.3% in I, p < 0.005). The average increase of hemoglobin and RBC was significantly higher in II group. An increase in hemoglobin did not correlate with the age of women (r = 0.07) or with the duration of pregnancy (r = 0.08). However, a negative correlation was found between basic hemoglobin level and its increase after treatment (r = 0.602). Conclusions: EPO administered with the oral dose of iron in pregnant women with anemia caused by iron deficiency shows higher effectiveness than the use of iron preparations parenterally. The usage of EPO during pregnancy is not related to any dangerous side effects for the mother or fetus.

The mode of action of 1-naphthylphthalamic acid (NPA) to induce conspicuous local stem swelling in the area of its application to the growing internode in intact Bryophyllum calycinum was studied based on the aspects of histological observation and comprehensive analyses of plant hormones. Histological analyses revealed that NPA induced an increase in cell size and numerous cell divisions in the cortex and pith, respectively, compared to untreated stem. In the area of NPA application, vascular tissues had significantly wider cambial zones consisting of 5–6 cell layers, whereas phloem and xylem seemed not to be affected. This indicates that stem swelling in the area of NPA application is caused by stimulation of cell division and cell enlargement mainly in the cambial zone, cortex, and pith. Comprehensive analyses of plant hormones revealed that NPA substantially increased endogenous levels of indole-3-acetic acid (IAA) in the swelling area. NPA also increased endogenous levels of cytokinins, jasmonic acid, and its precursor, 12-oxo-phytodienoic acid, but did not increase abscisic acid and gibberellin levels. It was shown, using radiolabeled 14C‑IAA, that NPA applied to the middle of internode segments had little effect on polar auxin transport, while 2,3,5-triiodobenzoic acid substantially inhibited it. These results strongly suggest that NPA induces changes in endogenous levels of plant hormones, such as IAA, cytokinins, and jasmonic acid, and their hormonal crosstalk results in a conspicuous local stem swelling. The possible different mode of action of NPA from other polar auxin transport inhibitors in succulent plants is extensively discussed.

The cabbage whitefly (CW), Aleyrodes proletella (L.) (Hemiptera: Aleyrodidae), is an important pest in Brassica oleracea L. crops. Little is known about the mechanisms of resistance to CW of savoy cabbage and kale cultivars. Light microscopy (LM) and scanning electron microscopy (SEM) analysis were used to determine the relationship between the morphological and anatomical features of savoy cabbage (Brassica oleracea L. convar. capitata (L.) Alef. var. sabauda L.) and kale (Brassica oleracea L. convar. acephala (DC.) Alef. var. sabellica L.) leaves and host suitability to colonization by CW. Two kale cultivars, “Redbor” and “Starbor”, and two savoy cabbage cultivars, “Gloriosa” and “Alcosa”, that differed in the degree of infestation by A. proletella were taken for histological analysis. The lowest infestation by all forms of A. proletella was observed on savoy cabbage cultivar “Alcosa” and kale cultivar “Starbor”. The reduced colonization by cabbage whitefly may be related to the structure of the epidermis and the anatomical features of the leaf. The leaves of “Starbor” and “Alcosa” had more folds in the epidermis, less numerous but larger stomata, and a more compact mesophyll structure compared to “Redbor” and “Gloriosa”. In both analysed species, there was no clear relationship between the thickness of the abaxial epidermal layer, thickness of the lamina, number of vascular bundles, and degree of infestation by the cabbage whitefly. This study identified promising sources of resistance to A. proletella among cultivars of savoy cabbage and kale. Varying infestation by CW was associated with morphological and anatomical characteristics of leaves. Further study is needed to confirm the relationship between insect resistance and leaf surface and morphological characteristics of leaves in a broader range of Brassica spp.

Hybrid varieties dominate the red beet market. The breeding process necessary to produce these cultivars is very difficult and time consuming. The application of in vitro gynogenesis can reduce the time needed to produce the corresponding homozygous pure lines to a few months. Our research team has developed a method to obtain red beet doubled haploid plants by gynogenesis. The best medium for gynogenesis induction is the B5 medium with the addition of 0.5 mg/L IAA, 0.2 mg/L BA, and 322 mg/L putrescine, whereas the best medium for shoot induction from embryos proved to be the MS medium supplemented with 0.1 mg/L NAA, 0.1 mg/L BA, and 0.5 mg/L putrescine. The shoots obtained were rooted on MS medium containing half the concentration of microelements and 3 mg/L NAA, 160 mg/L putrescine, and 20 g/L sucrose. Ploidy evaluation of gynogenetic plants was performed by flow cytometry and homozygosity or heterozygosity was determined by two isoenzymatic systems: PGI and AAT.

In this work, we present novel ex situ modification of bacterial cellulose (BC) polymer, that significantly improves its ability to absorb water after drying. The method involves a single inexpensive and easy-to-perform process of BC crosslinking, using citric acid along with catalysts, such as disodium phosphate, sodium bicarbonate, ammonium bicarbonate or their mixtures. In particular, the mixture of disodium phosphate and sodium bicarbonate was the most promising, yielding significantly greater water capacity (over 5 times higher as compared to the unmodified BC) and slower water release (over 6 times as compared to the unmodified BC). Further, our optimized crosslinked BC had over 1.5x higher water capacity than modern commercial dressings dedicated to highly exuding wounds, while exhibiting no cytotoxic effects against fibroblast cell line L929 in vitro. Therefore, our novel BC biomaterial may find application in super-absorbent dressings, designed for chronic wounds with imbalanced moisture level.

The interaction of methyl jasmonate (JA-Me) and indole-3-acetic acid (IAA) to induce the formation of the secondary abscission zone in the middle of internode segments of Bryophyllum calycinum was investigated in relation to auxin status and histology. When IAA at 0.1% (w/w, in lanolin) was applied to the segments, the formation of the secondary abscission zone at a few mm above the treatment in the apical direction was observed. On the contrary, IAA at 0.5% (w/w, in lanolin) did not induce the formation of the secondary abscission zone. JA-Me at 0.5% (w/w, in lanolin) applied to the middle of internode segments kept in the normal (natural) or inverted positions also induced the formation of the secondary abscission zone below and above parts of the treatment. IAA at 0.5% applied to the cut surface of the upper part of the segments completely prevented the formation of the secondary abscission zone induced by JA-Me. Simultaneous application of IAA 0.5% with JA-Me 0.5% in the middle part of the internode segments induced the formation of the secondary abscission zone at 10 mm to 12 mm above the treatment. Histological analyses indicated that the formation of the secondary abscission zone was characterized by the presence of newly synthesized cell plates that resulted from periclinal cell division within one layer of mother cells in stems. The effects of IAA (0.1%) and JA-Me (0.5%) on the formation of the secondary abscission zone were histologically similar. Comprehensive analyses of plant hormones revealed that the balance of the endogenous levels of IAA in both sides adjacent to the abscission zone was significantly disturbed when the secondary abscission formation was induced by the application of IAA. These results strongly suggest that an auxin gradient is important in the formation of the secondary abscission zone in the internode segments of B. calycinum, and IAA gradient results from polar IAA transport from the application site. IAA is important in the regulation of formation of the secondary abscission zone induced by JA-Me. Further possible mechanisms of the formation of the secondary abscission zone in the internode segments of B. calycinum are also discussed in the interaction of JA-Me and IAA.

Bacterial cellulose (BC) is recognized as a wound dressing material well-suited for chronic wounds; however, it has no intrinsic antimicrobial activity. Further, the formation of biofilms can limit the effectiveness of the pre-saturation of BC with antimicrobial agents. Here, to hinder biofilm formation by P. aeruginosa, we immobilized the hydrolytic domain of PelA (a glycohydrolase involved in the synthesis of biofilm polysaccharide Pel) on the surface of BC. The immobilization of 32.35 ± 1.05 mg PelA

Objectives. The aim of the study was to determine the quantitative and qualitative surface structure of contemporary RBCs in posterior teeth reconstructions: regular viscosity bulk fill and conventional composites, obtained after two-stage polishing procedure. Materials and Methods. Four conventional nanohybrid composites (Tetric EvoCeram, GrandioSO, Filtek Z550, and Ceram·X Mono) and four regular viscosity bulk fill composites (Tetric EvoCeram Bulk Fill, X-tra fil, Filtek Bulk Fill Posterior, and QuixFil) were tested. Samples of each RBC were prepared using PMMA cylindrical mold. After two-step polishing procedure, a surface geometry was evaluated under profilometry (Turbowave v. 7.36, Hommel-Etamic) and SEM (VEGA 3, Tescan Analytics). To evaluate differences between values, the following nonparametric tests were used: Friedman’s ANOVA, Wilcoxon’s matched-pair test, ANOVA Kruskal-Wallis, and Mann-Whitney U. Results. All conventional RBCs showed Ra values in the range of 0.20-0.26 μm. Bulk fill showed higher values in range of 0.49-1.36 μm except for Filtek Bulk Fill Posterior, which achieved 0.23 μm Ra value. SEM images of conventional RBCs were described as smooth surfaces with slight damage except for TEC, which presented smooth surface with no damage. Bulk fill composites showed rough surface, except for TBF, which presented smooth surface with slight damage. Conclusions. Regular viscosity bulk fill composites do not constitute a homogeneous group regarding surface roughness after polishing. They obtain, for the most part, poorer smoothness values after polishing than conventional RBCs.

Recenzja prezentuje monografię Travel, Modernism and Modernity, autorstwa brytyjskiego badacza Roberta Burdena, wydaną w 2015 roku. Głównym celem omawianej pracy jest ponowne odkrycie i dogłębne przeanalizowanie modernistycznego pisarstwa podróży. Podstawą rozważań Burdena są literackie i nieliterackie teksty brytyjskich i amerykańskich pisarzy: Josepha Conrada (1957–1924), Edwarda Morgana Forstera (1879–1970), Davida Herberta Lawrence’a (1885–1930), Henry’ego Jamesa (1843–1916) i Edith Wharton (1862–1937). Ich dzieła stawały się już wielokrotnie przedmiotem analizy historyków i teoretyków literatury – to, co odróżnia pracę Burdena od rozważań innych badaczy, to przede wszystkim szerokie, kontekstowe ujęcie ich twórczości. Burden prezentuje sylwetki pisarzy, podkreśla rolę inspiracji autobiograficznych w ich pisarstwie, analizuje je w kontekście historycznym, społecznym i psychologicznym. Motyw podróży nie jest jedynym elementem łączącym poszczególne teksty omawiane przez Burdena – cała jego książka poświęcona jest wyszukiwaniu paraleli i korespondencji, a także elementów oryginalnych, wyróżniających twórczość każdego z pięciorga anglojęzycznych autorów. Omawiane studium należy potraktować jako doskonałe podsumowanie wcześniejszych ujęć, jednocześnie oferujące interesujące rozważania m.in. na temat archetypicznego motywu podróży, wędrówki i poszukiwania – zarówno miejsca, jak i tożsamości (indywidualnej oraz narodowej). Pomimo że teksty omawiane przez Burdena powstawały na początku XX wieku, trudno oprzeć się wrażeniu, iż rozważania autora omawianej monografii są niezwykle aktualne również współcześnie.

IntroductionSocio-demographic forecasts indicate a stable increase in the population of elderly people, which gives rise to the need to examine the relationship between the acceptance of chronic illness and socio-demographic variables not only in terms of subjective negative emotions but also because of possible social consequences. The acceptance of a chronic disease is determined by factors related to its character including its severity and the discomfort it brings about but also by factors connected with the patient that is socio-demographic determinants. Objective: The objective of the study was to examine the relationship between socio-demographic variables and the acceptance of a chronic disease of locomotive organs.Material and methodsThe study was conducted in the group of 150 patients diagnosed with a systemic connective tissue disease during its stable phase. A socio-demographic questionnaire as well as a standardised Acceptance of Illness Scale (AIS) adapted by Juszczyński were applied in the study. The study was conducted in accordance with the recommendations of the Declaration of Helsinki.ResultsIn the group of 150 patients suffering from a systemic connective tissue disease the percentage of women was higher than the percentage of men (60.7% vs. 39.3%). The indicator of the acceptance of illness in the group examined reached 24.5 ±7.5. The strongest correlation was found between the acceptance level and married probants (eta = 0.26; p = 0.01), high education (eta = 0.24; p = 0.04) and working activity (eta = 0.20; p = 0.01).ConclusionsSocio-demographic factors which determine the level of illness acceptance include age, marital status, education and the source of income. The acceptance of illness in the examined group of patients with systemic connective tissue diseases reached 24.5.

Discussion about the borders restricting (unavoidable today) aestheticization of memory about the Holocaust experience is still valid – in the article are recalled some different strategies of remembering the Holocaust in the art using photography. Two of the artistic projects (Powidoki by Zbigniew Libera and Pocztówki z Auschwitz by Paweł Szypulski) are using authentic photographs to initialize the discussion about trivialization of image, removing it from its original context and, at the same time, “blunting” the sensitivity of the recipient. The other two works (Auschwitz, co ja tu robię by Mikołaj Grynberg and Miejsca nieparzyste by Elżbieta Janicka) are suspended between conversation and silence (two classic poles of memory about the Holocaust). All of these works are disputing with “fixed” models and imaginary experiences, deconstructing pathos, they are talking about the blurring memories and manipulating with memory, about competition of different historic narrations and attempts at overtaking the past, passing the traumatic experiences of the war and the Holocaust to the next generations.

Objectives: A proper implantation of trophoblastic cells and an appropriate metalloproteinases activity is required to cause disintegration of basal membranes of cells. The activity of tissue matrix metaloproteinases can be inhibited by their matrix inhibitors — TIMP-s. Survivin is a member of inhibitor of apoptosis proteins family (IAP), that suppresses caspase activation, influences VEGF expression and promotes proliferative action of endothelial cells. Material and methods: The aim of the study was to assess concentrations of two independent anti-apoptotic factors. TIMP-1 and survivin in serum of women in their third trimester of pregnancy and in umbilical cord blood of neonates – drawn separately from veins and arteries. The study group consisted of 29 pregnant women in physiological pregnancy and with correct fetal development, in gestational age between 37 to 40 weeks of gestation. Blood used in the study was collected from maternal cubital fossa veins and from neonatal umbilical cords (from veins and from arteries separately). The research was conducted using TIMP-1 and Survivin ELISA kits from R & D Systems according to manufacturers’ recommendations and protocols. Results: The concentrations of TIMP-1 were similar and independent of the source of blood samples. Arterial values of TIMP-1 in umbilical cord compared to maternal and fetal veins were slightly lower, but no statistical difference was found. The mean concentrations of Survivin were comparable but we found that in some cases the results in cord blood serum in both vessels-vein and arteries were almost negative. Arterial values of Survivin in umbilical cord compared to maternal blood were higher, but no statistical difference was found. Conclusions: In III-rd trimester of pregnancy parameters of Timp-1 and Survivin — anti-apoptotic substances concentration were similar in maternal and cord blood in both artery and vein. We found no increased activity of selected antiapoptotic factors.

So far there is no information about receiving red beet androgenic embryos by androgenesis. Several factors were tested which affected this process: starch accumulation in microspores, correlation between bud length and microsporogenesis course, induction and regeneration medium composition. Ploidy level of obtained regenerants were evaluated. Treating anthers with α-amylase or watering donor plants with gibberellin increased number of obtained androgenic embryos. The highest percentage (80%) of microspores at uninuclear stage appeared in buds with 1.3-1.5 mm. The B5 medium with 100 g·L-1 sucrose and 0.1 mg·L-1 2,4-D (2, 4-dichlorophenoxyacetic acid) proved to be better for inducing androgenesis than MS medium supplemented with 0.2 mg·L-1 BAP (6-benzylaminopurine) and 0.5 mg·L-1 IAA (indole-3-acetic acid). First androgenic embryos were placed on B5 medium without plant growth regulators and then on MS medium containing 0.2 mg·L-1 BAP and 1 mg·L-1 NAA (α-naphthaleneacetic acid). Androgenic embryos died on B5 regeneration medium without plant growth regulators. On MS medium first shoots and callus with and without roots were obtained. Rosettes withered during following passages whereas callus tissue developed further. The quantity of DNA in this tissue equivalent to 4X chromosomes.

Artykuł prezentuje refleksje związane z uniwersytecką dydaktyką literatury oraz koniecznością (uzasadnioną bądź nie) dostosowania metod kształcenia do możliwości współczesnego odbiorcy. Poruszone zostały w nim także kwestie dotyczącego definiowania nowego pokolenia studentów przez pryzmat cyfrowych technologii. Fundamentalne dla rozważań jest jednak zagadnienie akademickiej edukacji literackiej, która nierzadko nie wzbudza entuzjazmu wśród studentów, traktujących przedmiot jako mało praktyczny. W tekście odwołuję się do własnych doświadczeń dydaktycznych, wyrażając przekonanie, że odarta ze sztywnych reguł współczesnego kształcenia oraz uwolniona z konieczności urozmaicania dyskusji nowatorskimi metodami aktywizującymi studenta, literatura broni się sama, podlegając jednak w głównej mierze interpretacji przez pryzmat współczesności. Artykuł, zwracając uwagę na przemiany czytelnictwa, edukacji i historycznej pamięci, prezentuje stanowisko wyrażające potrzebę powrotu do klasycznych ścieżek edukacyjnych – dialogu i dyskusji o doświadczeniu czytelniczym.

Application of electromagnetic field in biotechnological processes is considered a promising tool to enhance their effectiveness and to control microbe-derived synthesis of desired compounds. The current work analyzes impact of non-continuous rotating magnetic field (RMF) on ability of two Komagataeibacter xylinus strains to produce bacterial cellulose (BC) and to consume fructose and ethanol. Exposure of K. xylinus ATCC 53524 to the RMF of 50 Hz frequency resulted in a statistically significant 10 % increase in BC yield and significant drop of fructose consumption comparing to untreated control setting. In turn, K. xylinus ATCC 53582 cultures, under the exposure to the RMF, showed no significant improvement in BC production but higher level of fructose and ethanol utilization, comparing to RMF-untreated strain. Exposure to the RMF, regardless the Komagataeibacter strain scrutinized, increased the cell proliferation rate, which was reflected in greater cell density and viability as compared to the non-exposed cultures. The results of our study show potential of RMF to improve efficiency of BC production, but at the same time they indicate that aforementioned potential is strictly related to specific K. xylinus strain applied.

The goal of this research was to evaluate a polymeric system, including biopolymers, as a multi-component material coating on paperboard for bread. The main aim of the research was to create a humidity-controlling packaging material. This means that the packaging material should contain filler which will absorb water or water vapour from the bread. The ideal packaging should have high barrier qualities against water vapour, enabling the possible release of water from the product (to maintain proper humidity inside the packaging). The preliminary storage tests made of the bread confirmed that the freshness of a product kept in a climatic chamber in RH = 70% was the highest. To summarise, the obtained packaging should maintain the required humidity (in the case of bread, the optimal humidity is 70%) within the packaging to keep the bread fresh after more than 72 h of storage. A &ldquo, sandwich&rdquo, form of (multilayer) packaging was indicated as a solution to this problem. The main objective of this packaging was to obtain two paper layers and one starch layer to increase water absorption from the bread. It was also important to obtain a thin, external hydrophobic layer to decrease the water vapour transmission rate of the packaging (WVTR). A number of &lsquo, &rsquo, packaging types were prepared, consisting of two sheets of paper with an external aquaseal coating and an internal starch coating (with a NaCl filler). The covered &lsquo, papers were then used to create packaging that could be used for the bread storage tests. The study results confirmed that the bread stored for 72 h in the &ldquo, packaging was found to be fresher than the same product stored in commercial paper packaging.

Bacterial cellulose (BC) is recognized as a wound dressing material well-suited for chronic wounds; however, it has no intrinsic antimicrobial activity. Further, the formation of biofilms can limit the effectiveness of the pre-saturation of BC with antimicrobial agents. Here, to hinder biofilm formation by P. aeruginosa, we immobilized the hydrolytic domain of PelA (a glycohydrolase involved in the synthesis of biofilm polysaccharide Pel) on the surface of BC. The immobilization of 32.35 ± 1.05 mg PelAh per g BC membrane resulted in an eight-fold higher P. aeruginosa cell detachment from BC membrane, indicating reduced biofilm matrix stability. Further, 1D and 2D infrared spectroscopy analysis indicated systematic reduction of polysaccharide biofilm elements, confirming the specificity of immobilized PelAh. Importantly, BC-PelAh was not cytotoxic towards L929 fibroblast cells. Thus, we conclude that PelAh can be used in BC wound dressings for safe and specific protection against biofilm formation by P. aeruginosa.

The aim of this study was to examine the influence of accelerated UV-aging on the activity against chosen microorganisms and the mechanical properties of poly-lactic acid (PLA) films enhanced with ZnO nanoparticles. The pure PLA films and tri-layered PLAZnO1%/PLA/PLAZnO1% films of 150 µm thickness were extruded. The samples were treated with UV-A and Q-SUN irradiation. After irradiation the antimicrobial activity and mechanical properties of the films were analyzed. The results of the study demonstrated that PLA films did not inhibit the growth of Staphylococcus aureus, Bacillus cereus, Escherichia coli, Bacillus atrophaeus, and Candida albicans cells. PLA films with incorporated zinc oxide nanoparticles decreased the number of analyzed microorganisms. Accelerated UV aging had no negative effect on the activity of the film containing nano-ZnO against Gram-positive bacteria, but it influenced the activity against Gram-negative cells and C. albicans. Q-SUN irradiation decreased the antimicrobial effect of films with incorporated nanoparticles against B. cereus. UV-A and Q-UV irradiation did not influence the mechanical properties of PLA films containing incorporated ZnO nanoparticles.

Portions of fresh Baltic cod fillets were packed into cellulose boxes (control samples), which were covered with Methyl Hydroxypropyl Celluloses (MHPC) coating with 2% polylysine. The cellulose boxes had square PE films and were enclosed in MHPC coating containing ZnO nanoparticles. The cod fillets were stored at 5 °C and examined after 72 h and 144 h storage times. Results obtained in this study showed that the textural parameters of the cod fillets increased, with both Springiness and Cohesiveness found greater after 144 h of storage for all analysed packaging materials. The Gumminess of fillets increased after storage, but the lowest increase was noted in cod samples that were stored in boxes containing PE films with ZnO nanoparticles. It was found that water loss from the cod fillets in these boxes was also lowest. The Adhesiveness of the fish samples stored in boxes devoid of active coatings also increased. In contrast to the packaging material devoid of active coatings, the storage of fillets in active coating boxes resulted in a decrease of adhesiveness. Microbial analysis showed that packaging material containing nano-ZnO was found to be more active against mesophilic and psychotropic bacterial cells than the coatings with polylysine after 72 h and 144 h of storage.

The purpose of this research was to examine the antimicrobial properties against Gram-positive bacteria, as well as the water vapour characteristic of polylactic acid (PLA) films covered with a methyl–hydroxypropyl–cellulose (MHPC)/cocoa butter carrier containing Eucomis comosa extract as an active substance. The second purpose of the study was to evaluate the influence of accelerated UV-A and Q-SUN irradiation (UV-aging) on the antimicrobial properties and the barrier characteristic of the coatings. The results of the study revealed that MHPC/cocoa butter coatings had no influence on the growth of Staphylococcus aureus, Bacillus cereus, and Bacillus atrophaeus. MHPC/cocoa butter coatings containing E. comosa extract reduced the number of bacterial strains. MHPC/cocoa butter coatings also decreased the water vapour permeability of PLA. It was shown that accelerated UV-A and Q-SUN irradiations altered the chemical composition of the coatings containing cocoa butter. Despite the alteration of the chemical composition of the layers, the accelerated Q-SUN and UV-A irradiation had no influence on the antimicrobial properties of E. comosa extract coatings against S. aureus and B. cereus. It was found that only Q-SUN irradiation decreased the coating activity with an extract against B. atrophaeus, though this was to a small degree.