Katarzyna Marchwińska

Increasing food consumption and waste generation are today’s most difficult economic and environmental challenges. In line with the sustainable production and consumption concept, wasted food, as a source of valuable resources, can be reused to produce new products of higher value than the raw materials from which they were made. This concept was used in this work to design products that are a plant-based alternative to fermented milk drinks, which arouse great interest among consumers due to their health-promoting properties. This study aimed to design potential probiotic beverages from food industry waste, including wheat-rye bread and chokeberry pomace, using lactic acid fermentation with different strains of lactic acid bacteria (LAB) and to evaluate selected quality features of the obtained beverages. In the first stage of the research, the group of LAB strains was tested for their efficiency in bakery waste fermentation, and then the potential probiotic properties of chosen LAB strains (Lactiplantibacillus plantarum A7, Lacticaseibacillus paracasei INV001, Lacticaseibacillus rhamnosus INV002, Lentilactobacillus buchneri P7, Loigolactobacillus coryniformis INV014) were characterized according to FAO/WHO requirements. For the prepared beverages, microbiological quality, antioxidant properties, and the content of polyphenolic compounds were determined. It was found that bakery and chokeberry waste may constitute a good base for obtaining fermented beverages with some beneficial properties, including a high number of potentially probiotic bacteria, reaching 10⁸ CFU/mL, and antioxidant properties, which positively verified their functional properties. The research confirms the high potential of lactic acid fermentation in managing food waste to create innovative, sustainable food products with probiotic properties.

Sustainable management of agri-food product safety presents a major challenge requiring extensive action to ensure food safety and consumer health. The pursuit of environmentally friendly solutions that will constitute an alternative to the chemical compounds commonly used in agriculture and the food industries is one of the most important problems. One solution is plant extracts containing various biologically active compounds and exhibiting antimicrobial activity. This study aims to determine the biological activity of extracts obtained from Origanum vulgare L. (leaves) by supercritical CO₂ (SC-CO₂) extraction using different reaction conditions and compositions. In vitro studies revealed antimicrobial activity against selected bacteria (including Salmonella Enteritidis, Listeria monocytogenes, and Staphylococcus aureus) and fungi (Fusarium spp.), depending mainly on the microorganism species; however, extraction conditions also influenced these properties. The microscopic observations established by optical and fluorescence microscopy showed the changes in the fungal cell’s viability and morphology. There was no observed significant release of intracellular material as stated based on ICP-MS analysis of sodium and potassium concentration. Antibiofilm properties of extract obtained by extraction at 40 °C were also demonstrated against S. aureus, P. aeruginosa, and L. monocytogenes, with stronger properties observed against Gram-positive bacteria. Phytochemical characterization of the extracts was determined using a liquid chromatography system with an orbitrap mass spectrometer (LC/MS), identifying, i.e., phenolic acids: protocatechuic, hydroxybenzoic, caffeic, and rosmarinic; flavonoids: luteolin, naringenin, and kaempferol; and terpenoids: oleanolic and ursolic acids.

Faced with challenges related to environmental degradation and the growing need for sustainable development, the food sector must look for innovative and ecological production solutions. One of the increasingly popular directions is the zero-waste approach, which limits waste generation and enables its reuse. This research aimed to evaluate selected quality indicators of the lactic acid fermentation process of beverages based on waste from the bakery industry (wheat–rye bread) to determine the optimal fermentation conditions using two strains of lactic acid bacteria: Lacticasibacillus paracasei and Lactiplantibacillus plantarum. Preliminary process optimization was carried out, taking into account the beverage composition, fermentation time, and starting culture. The process evaluation and the selection of the optimal variant were based on the microbiological quality, pH value, and antimicrobial activity of fermented beverages. The results showed that the bread waste may constitute a base for obtaining fermented beverages as evidenced by the high number of lactic acid bacteria, above 10⁸ CFU/mL, and low pH values (≤3.5) after the appropriate incubation time. Fermented beverages exhibited antibacterial properties against tested indicator microorganisms, which confirmed their functional properties. The analysis of the obtained results and the adopted assumptions enabled the selection of the most optimal variant—the beverage with ground flaxseed, fermented by L. paracasei for 24 h. The conducted research indicates great potential for lactic acid fermentation in the management of bakery waste to create innovative, sustainable food products with probiotic potential.

Plant diseases caused by pathogenic fungi generate large losses in crops and pose a threat to human and animal health. Since the European Green Deal put a strong emphasis on the need to reduce the use of chemical plant protection, interest in biological control has been growing. The present study aimed to investigate the efficacy of lactic acid bacteria (LAB) isolated from silages in the control of pathogenic fungi through in vitro, mini-plot, and field experiments. The tested LAB showed antifungal activity in vitro towards strains from the Fusarium, Alternaria, Rhizoctonia, Colletotrichum, and Sclerotinia genera; however, only five strains reached an activity ≥ 400 AU/mL towards all pathogenic fungi. The selected strains demonstrated high efficacy in reducing disease symptoms in plants in the mini-plot and field experiments. In the mini-plot experiment, stem smut of rye and wheat common bunt were reduced in the range 34.5–94.7% and 24.8–99.6%, respectively. In the field experiments, the efficacy of LAB in the control of rye and wheat disease differed and reached over 90% in some trials. The effectiveness of LAB in the control of seedling blight did not exceed 70%. A significant increase in yield (from 42.86 to 195.65%) was observed mainly in wheat cultivation. The increase in rye yield was observed only in chosen trials. No phytotoxicity was observed. The results indicate the potential possibilities of using LAB as a biocontrol agent.

Nowadays, plant-based fermented products are attracting a lot of consumer interest due to their probiotic and health-promoting properties. The aim of this study was to evaluate the microbiological quality and antioxidant activity of innovative fermented oat beverages with the addition of extracts and freeze-dried local fruit. In the first step, chokeberry and hawthorn were selected based on their antioxidant and antimicrobial properties. The final study material consisted of oat beverages fermented with the use of the Lactiplantibacillus plantarum DKK 003 strain for 20 h with the addition of 1 and 5% of extracts and freeze-dried fruits. It was found that freeze-dried chokeberry and chokeberry extracts showed a higher content of polyphenolic compounds than freeze-dried hawthorn and hawthorn extracts. After the fermentation process of the innovative beverages, the content of polyphenolic compounds remained the same or there was a slight decrease depending on the additive type. Antioxidant activity significantly decreased after 20 h of fermentation in all enriched oat beverages with no significant differences observed compared to control samples. The obtained fermented beverages were characterised by a high lactic acid bacteria count (above 8 log CFU/mL), a low pH (approximately 4.15), and no microbiological contamination. Oat fermented beverages with fruit additives can be good dietary enrichment products.

Microbial contamination of agriculture and food commodities may cause significant losses, with economic, social and environmental consequences

Glechoma hederacea var. longituba is a herbaceous plant from the Lamiaceae family, used in herbal medicine. In this work, we aimed to assess the total phenolic content, antioxidant, antimicrobial and antibiofilm activity of extracts obtained from G. hederacea via supercritical dioxide extraction with methanol as a co-solvent under different extraction conditions. The results showed that the activity of the obtained SC-CO₂ extracts is strongly dependent on the extraction temperature. Significantly higher total polyphenol content, as well as antioxidant and antimicrobial activity towards bacteria and yeasts, was observed in the extract obtained at 40 °C, compared to extracts obtained at 50 °C and 60 °C; however, antifungal activity against filamentous fungi was not dependent on the extraction conditions. Antimicrobial activity also depended on the microorganism type. Higher sensitivity was exhibited by Gram-positive bacteria than by Gram-negative bacteria, with S. aureus and P. aeruginosa being the most sensitive species among each group. The most susceptible fungi were Candida albicans and Sclerotinia sclerotiorum. The antibiofilm activity was differentiated and depended on the extraction conditions, the microorganism and the method of biofilm treatment. All tested extracts inhibited biofilm formation, with the extract obtained at 40 °C showing the highest value, whereas only extract obtained at 60 °C efficiently removed mature biofilm.

The presence of Fusarium fungi and their toxic metabolites in agricultural crops contributes to significant quantitative and qualitative losses of crops, causing a direct threat to human and animal health and life. Modern strategies for reducing the level of fungi and mycotoxins in the food chain tend to rely on natural methods, including plant substances. Essential oils (EOs), due to their complex chemical composition, show high biological activity, including fungistatic properties, which means that they exhibit high potential as a biological plant protection factor. The aim of this study was to determine the fungistatic activity of three EOs against F. graminearum, and the reduction of mycotoxin biosynthesis in corn and wheat grain. All tested EOs effectively suppressed the growth of F. graminearum in concentrations of 5% and 10%. Cinnamon and verbena EOs also effectively reduced the ergosterol (ERG) content in both grains at the concentration of 1%, while at the 0.1% EO concentration, the reduction in the ERG amount depended on the EO type as well as on the grain. The degree of zearalenone (ZEA) reduction was consistent with the inhibition of ERG biosynthesis, while the reduction in deoxynivalenol (DON) was not consistent with this parameter.

Animal microbiota is becoming an object of interest as a source of beneficial bacteria for commercial use. Moreover, the escalating problem of bacterial resistance to antibiotics is threatening animals and humans; therefore, in the last decade intensive search for alternative antimicrobials has been observed. In this study, lactic acid bacteria (LAB) were isolated from suckling and weaned pigs feces (376) and characterized to determine their functional properties and usability as pigs additives. Selection of the most promising LAB was made after each stage of research. Isolates were tested for their antimicrobial activity (376) and susceptibility to antibiotics (71). Selected LAB isolates (41) were tested for the production of organic acids, enzymatic activity, cell surface hydrophobicity and survival in gastrointestinal tract. Isolates selected for feed additive (5) were identified by MALDI-TOF mass spectrometry and partial sequence analysis of 16S rRNA gene, represented by Lentilactobacillus, Lacticaseibacillus (both previously classified as Lactobacillus) and Pediococcus genus. Feed additive prototype demonstrated high viability after lyophilization and during storage at 4 °C and − 20 °C for 30 days. Finally, feed additive was tested for survival in simulated alimentary tract of pigs, showing viability at the sufficient level to colonize the host. Studies are focused on obtaining beneficial strains of LAB with probiotic properties for pigs feed additive.