The essential oils of three different growth stages of Trifolium pratense L. (TP1, TP2 and TP3) were investigated by gas chromatography-mass spectrometry and tested for their antioxidant and antimicrobial activities. The highest content of volatile compounds was found in the essential oil sample TP1, where terpenes such as β-myrcene (4.55%), p-cymene (3.59%), limonene (0.86%), tetrahydroionone (1.56%) were highlighted due to their biological activity. The antioxidant activity was determined by following the scavenging capacity of the essential oils for the free radicals DPPH^·, NO^· and O₂^·-, as well as effects of the investigated oils on lipid peroxidation (LP). In all three cases, the sample TP1 showed the best radical-capturing capacity for DPPH^· (27.61 ± 0.12 µg/mL), NO^· (16.03 ± 0.11 µg/mL), O₂^·− (16.62 ± 0.29 µg/mL) and also had the best lipid peroxidation effects in the Fe²⁺/ascorbate induction system (9.35 ± 0.11 µg/mL). Antimicrobial activity was evaluated against the following bacteria cultures: Escherichia coli (ATCC10526), Salmonella typhimurium (ATCC 14028), Staphylococcus aureus (ATCC 11632) and Bacillus cereus (ATCC 10876). None of the examined essential oil samples showed inhibitory effects on the tested bacterial strains.

Microbiologically induced CaCO₃ precipitation (MICP) is a well-known bio-based solution with application in environmental, geotechnical, and civil engineering. The significance of the MICP has increased explorations of process efficiency and specificity via natural bacterial isolates. In this study, comprehensive profiling of five soil ureolytic Bacillus strains was performed through a newly formed procedure that involved six steps from selection and identification, through kinetic study, to the characterization of the obtained precipitates, for the first time. To shorten the whole selection procedure of 43 bioagents with the MICP potential, Standard Score Analysis was performed and five selected bacteria were identified as Bacillus muralis, B. lentus, B. simplex, B. firmus, and B. licheniformis by the MALDI-TOF mass spectrometry. Despite following the targeted activity, kinetic studies were included important aspects of ureolysis and the MICP such as cell concentration, pH profiling, and reduction in calcium ion concentration. At the final step, characterization of the obtained precipitates was performed using FTIR, XRD, Raman, DTA/TGA, and SEM analysis. Although all tested strains showed significant potential in terms of precipitation of calcite or calcite and vaterite phase, the main differences in the MICP behavior can be observed at the bacterial strain level. B. licheniformis showed favorable behavior compared to the reference Sporosarcina pasteurii DSM 33.

Kombucha is a fermented tea beverage, which is traditionally prepared by fermenting sweetened black tea with tea fungus, which is a consortium of yeasts and acetic acid bacteria. In this paper, viability of selected wild strains of lactobacilli during Kombucha fermentation, their interaction with...

Yeasts are considered an extraordinary alternative source of natural carotenoids and pigmented terpenoids with multiple applications. Production of carotenoids by yeast fermentation technology has many benefits; it is cost-effective, easily scalable, and safe. The aim of this research is the isolation of yeasts from natural resources and selection of the most potent bioagent for carotenoid production. Additionally, an upgraded carotenoid extraction protocol we established, which implies the testing of four methods for cell lysis (hydrochloric acid treatment, ultrasound treatment, milling treatment, and osmotic pressure treatment), three extraction methods (conventional extraction, ultrasound extraction, and conventional + ultrasound extraction), and three extraction solvents (acetone, isopropanol/methanol (50:50), and ethanol). For the first time, the obtained results were further modeled by an artificial neural network (ANN). Based on the obtained maximal carotenoid yield (253.74 ± 9.74 mg/100 g d.w) for the best-performing Rhodotorula mucilaginosa, the optimized extraction procedure involving milling treatment (for cell lysis) and conventional extraction with acetone (for carotenoid extraction) convincingly stood out compared to the other 35 tested protocols. Therefore, the selected carotenoid extraction protocol was verified with respect to its universality for all other yeast isolates, demonstrating its simplicity and effectiveness.

Layered double hydroxides (LDHs) have gained increasing attention as versatile materials in environmental remediation, particularly for wastewater treatment. Their unique structural properties, such as tunable metal cation composition, interlayer anion exchange, and structural memory effects, make them suitable materials for a broad range of applications. In addition to these intrinsic properties, thermally treated LDH-derived mixed metal oxides have emerged as a key focus, exhibiting enhanced activity through tailored structural, electronic, and textural properties. This review presents an up-to-date and systematic overview of recent advancements in the design and application of LDH-based materials, with a focus on photocatalytic degradation of organic dyes, adsorption of contaminants, and light-activated antimicrobial activity. The review also explores emerging photocatalytic applications in correlation with surface engineering, heterojunction formation, and thermal activation to enhance the overall efficiency. In addition, the synergy between antimicrobial activity and photocatalysis is discussed in the context of achieving multifunctional microbial control in water treatment. Finally, current challenges and future perspectives are addressed, including recyclability, scale-up potential, and the development of LDH composites as sustainable alternatives to conventional photocatalysts. This review aims to support researchers in advancing LDH-based technologies toward more efficient and versatile environmental remediation solutions.