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Cyclodextrins, commonly used as excipients in antifungal formulations to improve the physicochemical properties and availability of the host molecules, have not been systematically studied for their effects and bioactivity without a complex active substance. This paper evaluates the effects of various cyclodextrins on the physiology of the test organism Candida boidinii. The research examines their impact on yeast growth, viability, biofilm formation and morphological changes. Native ACD, BCD, randomly methylated α- and β-CD and quaternary ammonium α-CD and β-CD were investigated in the 0.5–12.5 mM concentration range in both static and dynamic systems. The study revealed that certain cyclodextrins exhibited notable antifungal effects (up to ~69%) in dynamic systems; however, the biofilm formation was enhanced in static systems. The magnitude of these effects was influenced by several variables, including the size of the internal cavity, the concentration and structure of the cyclodextrins, and the contact time. Furthermore, the study found that CDs exhibited distinct effects in both static and dynamic systems, potentially related to their tendency to form aggregates. The findings suggest that cyclodextrins may have the potential to act as antifungal agents or growth promoters, depending on their structure and surrounding environments. [ABSTRACT FROM AUTHOR]

The performance of combined reduction of nitrate (NO3−) to dinitrogen gas (N2) and oxidation of arsenite (As[III]) to arsenate (As[V]) by a bioelectrochemical system was assessed, supported by ecotoxicity characterization. For the comprehensive toxicity characterization of the untreated model groundwater and the treated reactor effluents, a problem‐specific ecotoxicity test battery was established. The performance of the applied technology in terms of toxicity and target pollutant elimination was compared and analyzed. The highest toxicity attenuation was achieved under continuous flow mode with hydraulic retention time (HRT) = 7.5 h, with 95%, nitrate removal rate and complete oxidation of arsenite to arsenate. Daphnia magna proved to be the most sensitive test organism. The results of the D. magna lethality test supported the choice of the ideal operational conditions based on chemical data analysis. The outcomes of the study demonstrated that the applied technology was able to improve the groundwater quality in terms of both chemical and ecotoxicological characteristics. The importance of ecotoxicity evaluation was also highlighted, given that significant target contaminant elimination did not necessarily lower the environmental impact of the initial, untreated medium, in addition, anomalies might occur during the technology operational process which in some instances, could result in elevated toxicity levels. [ABSTRACT FROM AUTHOR]

The soil degradation processes may cause long-term serious problems in various areas of life on Earth, thus mitigation of these processes by environmental-friendly, innovative soil protection methods is necessary. Biochar produced from organic wastes or by-products by pyrolysis may have several positive properties as additive in soil improvement technologies. In our complex research applying a tiered approach we assessed the main properties of a beech-wood biochar produced from a high volume by-product of a food industry technology. Then we studied in 4-months microcosm experiments the applicability of this biochar as amendment mixed into an acidic, degraded sandy soil. In addition, to forecast the long-term effects of the biochar, artificial physical and biological aging experiments were conducted. Based on the results, the beech-wood biochar was able to shift the acidic pH of the soil to the alkaline range and the electric conductivity of the soil increased with incremental biochar doses. Biochar addition significantly increased the microbial activity, as well. The results had clearly shown that during the mid-term experiment not even the highest biochar dose (15%) had inhibitive effect, but it rather improved several soil parameters. Furthermore, the biochar had positive effect on the soil water holding capacity, and the available soil nutrient and organic matter content. The results of the aging experiments generally showed also favourable effects and demonstrated that the aging-mediated changes differed according to the soil types. Therefore, we have concluded that biochar application requires a char by char and soil by soil testing prior to field application. [ABSTRACT FROM AUTHOR]

Drying is broadly used to enhance the stability of thermosensitive biologics (for example proteins, probiotics) despite the risk of inadequate product quality after the drying process. Continuous fluidized bed drying is an attractive technology for these active pharmaceutical ingredients owing to the short mean residence time at elevated temperatures, compared to batch-type drying technologies and the possibility to closely monitor and precisely control the process. In this work, an integrated continuous granulation – drying – milling line was used to manufacture granules ready for tableting from a suspension of probiotic bacteria. A mechanistic drying model suitable to predict the product temperature in the dryer and the moisture content of the granules was built. This allowed finding the optimal operating conditions for maximal bacteria load and low residual moisture content in the product, which has the potential to enable direct integration with the tableting unit. A continuous experiment was carried out with the in silico - optimized process parameters. The produced granules had high probiotic content and were suitable for tableting, which demonstrates the usefulness of the model-based process optimization in complex integrated pharmaceutical manufacturing processes. [ABSTRACT FROM AUTHOR]