Maria Jolanta Chmiel

Novel double-layer films based on furcellaran (FUR) and gelatin (GEL) with the addition of Phytolacca americana L. (PA) extract were used as active packaging for African catfish fillets. Films with PA extract have been shown to minimize the catfish spoilage effects, expressed as odor reduction compared to control samples; however, neither the films nor the PA extract exhibited antimicrobial activity against tested groups of microorganisms (fungi, lactic acid bacteria, Enterobacterales and psychrotrops) or specified microorganisms (E. coli, S. aureus, S. cerevisiae). The tested films demonstrated antioxidant activity determined by the DPPH, ABTS, FRAP, CUPRAC and Folin–Ciocâlteu methods. Cytotoxicity analysis showed that the PA extract affected tested cell lines (PNT2—prostate epithelial cells, HepG2—human liver cells, HaCaT—normal human keratinocytes and Nty-hori 3-1) only to a small extent—the calculated IC₅₀ values exceeded the maximal tested concentration of 500 µg/mL.

Modern biotechnology is the processing of biomass into innovative bio-based products and using the unique properties of living organisms to obtain valuable biomaterials or modify standard organisms/materials. This chapter focuses on the importance and applications of biotechnology worldwide throughout history. It begins with a discussion of the history and evolution of biotechnology before going on to define all the separate branches of modern biotechnology. Then, referring to the biotechnology colour code, it discusses examples of applications of green and white biotechnology in the bioeconomy, considering the use of genetically modified organisms and bioproducts in agriculture (green) and applications of biotechnology in industry for the production of biopolymers and renewable energy (white). The conclusion is that the bioeconomy would not have been created and could not have developed without the contributions that biotechnology has made to sustainable development.

The paper presents an assessment of the mycological air quality in classrooms of school buildings located in Lesser Poland. In 10 schools, 5 sampling points were designated: 4 indoors and 1 as an "outdoor background". A 6-stage Andersen impactor was used to collect fungal aerosol samples. During sampling, dust measurements were made (using the DustTrak II dust meter) as well as temperature and relative humidity. The predominant genera of fungi were determined by the MALDI-TOF MS method. The results indicated no statistically significant differences in indoor air fungal concentrations among the tested locations (p>0.05). The highest concentrations were observed in large classrooms (max. 2,678 CFU∙m-3), however, these differences were not statistically significant across different types of school rooms (Kruskal-Wallis test: p>0.05). All rooms exhibited similar levels of fungal aerosol contamination. Relative air humidity had a significant influence on the number of microorganisms. The most frequently isolated fungi belonged to Cladosporium, Penicillium, and Aspergillus genera. Fungal aerosol concentrations in the tested classrooms did not exceed proposed limit values for this type of indoor environment. The results suggest that natural ventilation in classrooms is insufficient to ensure adequate microbiological quality of indoor air.

Essential oils exhibit strong antimicrobial effects that can serve as a substitute for synthetic pesticides. However, many reports mention the use of essential oils in protecting above-ground plant organs and storing raw materials and seeds, but only a few address the effects of treatments on soil microbiota. Regarding this, it is necessary to find a solution that will prevent the rapid degradation of oils in soil and extend the period of their action on the soil microbiota. The solution to this problem can be microencapsulation, where the choice of carrier plays a key role. In our experiment, maltodextrin was studied, often used in the microencapsulation of essential oils. It was examined independently in two doses (M1 and M2, with 50 and 200 g kg⁻¹, respectively) and a combination with two essential oils known for their antimicrobial activity. We hypothesized that the selected microbial communities would react differently to the stress caused by maltodextrin-encapsulated essential oils. The serial dilution method assessed the number of colony-forming units (CFU) of bacteria, fungi, and actinomycetes. As the goal of microencapsulation was to prolong the effect of essential oils, their reaction was observed over a longer period. The soil microbial populations were examined in sandy and loamy soil at 1, 7, 14, and 78 days after encapsulated essential oils were mixed with the soil samples. In both types of soil, a significant increase in bacteria and actinomycetes was observed with maltodextrin in both doses. Encapsulated peppermint and caraway oils had different effects on microbes, both inhibitory and stimulatory. It is also important to note that peppermint with a smaller dose of maltodextrin significantly inhibited the growth of fungi in sandy soil in all measurements, as well as that caraway oil with a higher dose of maltodextrin significantly stimulated the growth of bacteria and actinomycetes in sandy soil. The higher dose of maltodextrin could explain this stimulation. Further research is recommended to test different doses of essential oils and maltodextrin, which would lead to the optimal dose of both wall and core materials.

Streszczenie: Mleko surowe, które nie zostało poddane obróbce termicznej, może być ważnym źródłem drobnoustrojów chorobotwórczych przenoszonych drogą pokarmową, głównie takich jak: patogenne szczepy Escherichia coli , bakterie z rodzaju Salmonella , niektóre paciorkowce kałowe czy Listeria monocytogenes . Najgroźniejszym z patogenów związanych z surowym mlekiem jest E. coli VTEC, która wytwarza werocytotoksyny – zwłaszcza szczep O157:H7. Enterococcus spp. jest jednym z czynników zapalenia wymienia u krów i dlatego często występuje w surowym mleku, co może stanowić zagrożenie dla konsumentów. Spożywanie mleka surowego jest dobrym wyborem, pod warunkiem, że mamy gwarancję wysokiego poziomu higienicznego jego pozyskiwania.

Streszczenie: Mleko surowe, które nie zostało poddane obróbce termicznej, może być ważnym źródłem drobnoustrojów chorobotwórczych przenoszonych drogą pokarmową, głównie takich jak: patogenne szczepy Escherichia coli , bakterie z rodzaju Salmonella , niektóre paciorkowce kałowe czy Listeria monocytogenes . Najgroźniejszym z patogenów związanych z surowym mlekiem jest E. coli VTEC, która wytwarza werocytotoksyny – zwłaszcza szczep O157:H7. Enterococcus spp. jest jednym z czynników zapalenia wymienia u krów i dlatego często występuje w surowym mleku, co może stanowić zagrożenie dla konsumentów. Spożywanie mleka surowego jest dobrym wyborem, pod warunkiem, że mamy gwarancję wysokiego poziomu higienicznego jego pozyskiwania.

Historical facilities such as churches, crypts, libraries and museums are crucial for preserving cultural heritage but at the same time, they are frequently visited tourist objects and working environment. The aim of this study was to assess whether there are differences in the concentration and size distribution of bacterial and fungal aerosol in the mentioned groups of historical objects in Kraków, as well as to determine if there is tendency for seasonal fluctuations of bioaerosol concentrations, and what environmental parameters affect them most significantly. The concentrations of bacterial and fungal aerosol were measured in ten historical objects—churches, crypts, libraries and museums—using a six-stage Andersen impactor. Microbiological analyses were accompanied by measurements of particulate matter (PM₁₀, PM₄, PM_2.5 and PM₁) and microclimatic parameters. The results showed that the studied objects differ in terms of bioaerosol levels, but the differences were not drastic and in terms of bacterial aerosol concentrations the objects can be arranged as follows: churches > libraries > museums > crypts, while for fungal aerosol the order would be: churches > museums > crypts > libraries. The concentrations of bioaerosol did not exceed the safety levels for human exposure, but the levels suggesting possible threat of biodeterioration and the presence of internal source of contamination were exceeded in nearly all sites. The share of respirable fraction of bioaerosol was high (42.1–90.5% for bacteria and 80.7–94.7% for fungi). Bioaerosol concentration was most significantly associated with indoor temperature, and the impact of particulate matter was only moderate.

Drobnoustroje odgrywają ważną rolę w procesie pozyskiwania składników odżywczych przez rośliny. Większość interakcji pomiędzy mikroorganizmami a roślinami zachodzi w ryzosferze, żyznej strefie aktywnej mikroflory glebowej. Prawidłowe funkcjonowanie tych procesów zależy od występującej w glebie puli drobnoustrojów jak i od właściwości gleby. Najważniejszymi organizmami glebowymi promującymi wzrost i rozwój roślin są Gram-ujemne bakterie brodawkowe asymilujące azot atmosferyczny oraz bakterie nitryfikacyjne utleniające amoniak do przyswajalnych przez rośliny form azotu. Endofityczne bakterie promujące wzrost roślin odpowiadają za wytwarzanie substancji hormonalnych stymulujących rozwój roślin i redukujących stres środowiskowy. W ryzosferze występują także grzyby mykoryzowe powiększające powierzchnię chłonną korzeni i ułatwiające dostęp najważniejszych przyswajalnych biogenów, dodatkowo chroniąc roślinę przed patogenami. Ponadto mikroorganizmy glebowe odpowiedzialne są za procesy rozkładu, bilansując zasobność gleby w składniki odżywcze, hormony czy witaminy.