2017, Vol. 81 No. 2

Stały URI dla kolekcjihttp://hdl.handle.net/11652/5432

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Antimicrobial effect of lining leather fatliquored with the addition of essential oils
(Wydawnictwo Politechniki Łódzkiej, 2017) Bielak, Elżbieta; Syguła-Cholewińska, Justyna
Footwear, especially those often and intensively used, provides an ideal environment for microbial growth. An appropriate high temperature and moisture content inside it enhance bacterial and fungal colonization by microbes. These microorganisms can be potentially pathogenic to human health and responsible for destruction of shoes materials from which the parts inside the shoe are made. In previous studies it has been shown that the addition of essential oils of antiseptic activity at leather finishing operations allows a leather to get antimicrobial properties. The aim of this paper is to assess the durability of antimicrobial effect of leather fatliquored with the addition of cinnamon, thyme and oregano essential oils at concentration of 5% per leather weight. Antimicrobial activity was evaluated according to guidelines of PN-EN ISO 20645:2006 “Textile fabrics – determination of antibacterial activity – Agar diffusion plate test” after 36-month storage. The obtained results have indicated that leathers under investigations show antimicrobial activity against E. coli, S. aureus and C. albicans strains even 3 years after fatliquoring. The use of natural bioactive substances such as cinnamon, thyme and oregano oils at concentration of 5% per leather weight in the leather finishing process may be an alternative to biocides used in the tanning industry as well it can improve hygienic properties of shoes, internal parts of which are made of such finished leathers.
A comparison of two enzymatic methods of clinical dextran production
(Wydawnictwo Politechniki Łódzkiej, 2017) Sikora, Barbara; Kubik, Celina; Bielecki, Stanisław
The aim of this study was to evaluate and compare of the two enzymatic methods of clinical dextran production were compared. The reactions were performed at 30°C and pH 5.4 in solutions containing different amounts of sucrose, using dextransucrase (DS, in the presence of dextranase (D) (method 1) or acceptor dextrans (method 2). The activity of Leuconostoc mesenteroides L dextransucrase (DS), which converts sucrose to dextran, was 0.4 U ml-1 in both the methods. As much as 53-56% of clinical dextran fractions were obtained for 28 h from 10% sucrose solutions, which contained 1.5% or 2.5% acceptor dextrans with molecular mass of 10 and 15 kDa, respectively. Approximately 50% of these fractions was obtained (also in 28 h) from 10% sucrose solutions by using 0.004 U ml-1 of DN, added to reaction mixtures 5 h later than Our experiments indicate that the clinical dextran can be efficiently produced by using both the compared methods, which employ either acceptor dextrans with definite molecular mass, or the dextranase. Because consumption of the latter enzyme is rather small, and it is easily available, thus this method should be attractive for clinical dextran manufacturers.
Effect of thermal processing on antioxidant power and thiosulfinate content in Brussels sprouts juices
(Wydawnictwo Politechniki Łódzkiej, 2017) Kot, Mirosława; Olech, Zofia
The aim of this study was to elucidate the influence of thermal processing at 22-95oC on the antioxidant ability of Brussels sprouts juice and its thiosulfinate content. The antioxidant power was determined by FRAP, Folin-Ciocalteu and DPPH radical scavenging methods. Thiosulfinate concentration was assayed by Han's procedure. It was shown that the increase of processing temperature decreased of the antioxidant ability determined by Folin-Ciocalteu method. However, FRAP and DPPH scavenging showed increase by 20% of the antioxidant power in the final heating step (95oC). The increasing processing temperature resulted in decreasing thiosulfinate concentration until the total loss. This proved that the thiosulfinate present in Brussels sprouts juice is thermolabile compound (not resistant for high temperature). The total loss of the thiosulfinate in high temperature did not reflect the change in antioxidant power. This fact indicated that there was no impact of the thiosulfinate on antioxidant abilities of Brussels sprouts juice or the impact was insignificant among the abundance of other antioxidants. The results showed a good correlation between FRAP and DPPH assays of antioxidant power determination in contrast to correlation with the data of Folin-Ciocalteu procedure.
Elimination of ochratoxin A by lactic acid bacteria strains isolated from chickens and their probiotic characteristics
(Wydawnictwo Politechniki Łódzkiej, 2017) Kupryś-Caruk, Marta; Stefańska, Ilona; Chabłowska, Beata
The aim of the study was to evaluate the ability of lactic acid bacteria strains, isolated from the gastrointestinal tract of chickens, to eliminate ochratoxin A (OTA) in vitro and to investigate whether the mechanism of OTA reduction is adsorption or hydrolysis. The probiotic characteristics of the strains, such as their growth performance and synthesis of lactic acid at 42°C, inhibition of Salmonella spp. and Escherichia spp. growth and susceptibility to antibiotics, was also evaluated. Ochratoxin A reductions in MRS broth depended on the tested strain and ranged from 1% to 29%. The level of OTA reduction was higher at 30°C than at 37 and 42°C and there were no significance differences between OTA reduction obtained with live and heat-treated bacteria cells. The evaluation of probiotic characteristics showed that Pediococcus acidilactici KKP 879 was the strain with more potential to develop a probiotic culture for chickens.
In vitro anti-adherence effect of probiotic Lactobacillus strains on human enteropathogens
(Lodz University of Technology Press, 2017) Nowak, Adriana; Motyl, Ilona
Probiotic bacteria possess great potential for producing antimicrobial substances that inhibit and control pathogenic bacteria in the human gastrointestinal tract. The aim of this study was to determine the anti-adherence properties of the probiotic Lactobacillus strains Lb. rhamnosus ŁOCK 0900, Lb. rhamnosus ŁOCK 0908, and Lb. casei ŁOCK 0919 (individually and in a 1:1:2 mixture) against the reference pathogens Clostridium difficile (ATCC 9689), Enterococcus faecalis (ATCC 29212), Listeria monocytogenes (ATCC 19115), and Staphylococcus aureus (ATCC 6538) using the Caco-2 human colon adenocarcinoma cell line. The mixture of probiotic strains inhibited the adherence of all pathogens, from 10.2% for E. faecalis ATCC 29212 to 97.2% for L. monocytogenes ATCC 19115. Of all the tested probiotic strains, Lb. casei ŁOCK 0919 reduced the adherence of S. aureus ATCC 6538 to the greatest extent (by 45.9%). These results suggest that adherence inhibition may involve competition for eukaryotic cell receptors and probiotic bacteria could protect the host cells from pathogen colonization and disease.
List of Reviewers
(Wydawnictwo Politechniki Łódzkiej, 2017)
Production of co-immobilized dextransucrase and dextranase preparations and their application in isomalto-oligosaccharides synthesis
(Wydawnictwo Politechniki Łódzkiej, 2017) Sikora, Barbara; Kubik, Celina; Bielecki, Stanisław
Dextransucrase (DS) from Leuconostoc mesenteroides and dextranase (DN) from Penicillium funiculosum were co-immobilized by entrapment in calcium alginate and used to produce isomaltooligosaccharides (IMOs) from sucrose. DS convert sucrose into dextran, which is the substrate for DN, so that IMOs are products of dextran hydrolysis. Before the co-immobilization DS was cross-linked with glutardialdehyde (GA), while DN was adsorbed on hydroxyapatite (HAp). Cross-linking was essential for the stability of DS and pre-immobilization of DN to prevent enzyme from leaking out of the alginate beads. Operational stability of co-immobilized preparations of DS and DN was estimated based on amounts of isomaltose and isomaltotriose formed during successive 24h processes of IMOs synthesis, carried out at 30oC, pH 5.4 and 200 rpm in 10% (w/v) sucrose solutions. Preparation characterized by the initial DS/DN activities ratio of 1/14 was found to maintain these activities at least 100 h of IMOs synthesis (5 repeated batch reaction).
Safety of workers exposed to harmful airborne bioaerosols – legal status and innovations
(Wydawnictwo Politechniki Łódzkiej, 2017) Majchrzycka, Katarzyna; Okrasa, Małgorzata; Szulc, Justyna; Gutarowska, Beata
Filtering respiratory protective equipment is commonly used for protection against bioaerosols in industrial workplaces. However, the EU legislation does not specify the requirements for its antimicrobial properties. The result is that in the market there is no equipment available that would ensure complete safety of workers exposed to inhalation of harmful bioaerosols. This is particularly important in the case of equipment intended for multiple and long-term use. The aim of this study was to develop an innovative filtering half mask for the protection of respiratory tract that would have confirmed antimicrobial properties. The half mask was tested for compliance with EN 149:2001+A1:2009, and the survival rate of microorganisms in nonwovens was determined (E. coli bacteria and A. niger moulds). The reduction in the number of E. coli bacteria was 98.69% and the reduction in the number of A. niger moulds was 67.68% after 32 h of storage under conditions simulating the conditions of use of the equipment. It was found that the biocidal activity of the half mask is sufficient to ensure a significant reduction in the number of microorganisms during its long-term use in the workplace. This in turn means that continuous disinfection of respiratory protective equipment would be maintained even without employees’ intervention, which is not possible in case of standard respiratory protective equipment.
Zinc and nano-ZnO – influence on living organisms
(Lodz University of Technology Press, 2017) Mielcarz-Skalska, Lidia; Smolińska, Beata
The use of zinc is very common in many industries. The multitude of advantages, and capabilities make use of different forms of penetration of zinc into the environment. Due to its ability to migrate, zinc is also accumulated in living organisms. Zn is an essential trace element but both the deficiency or excess are extremely dangerous for living organisms. Nowadays nanozinc has been increasingly used. Nanozinc is a component of daily used products, like plastics, ceramics, glass, cement, rubber, foods and many others. This leads to spreading nanozinc the environment with the possibility of its penetration into living organisms. This article is a review of the impact of zinc and zinc nanoparticles on a variety of organisms: ranging from microorganisms through plants and animals, to people.