Basic Chemical Composition, Antioxidant Activity and Selected Polyphenolic Compounds Profile in Garlic Leaves and Bulbs Collected at Various Stages of Development.

Garlic is commonly used as vegetable or spice and as a herb in folklore as well as traditional medicine in many countries. The current study aimed to compare the chemical composition, antioxidant activity, and the content of selected polyphenolic compounds in cloves as well as leaves of winter garlic plants of the Harnas and Ornak cultivars, which are of Polish origin. Garlic was grown from cloves for three years (2018-2020) in the experimental field of the University of Agriculture in Krakow, Poland. The research material was harvested on three dates: May; June, unripe garlic plants; and in July, the plant at full maturity. The content of vitamin C in the fresh material was determined. The proximate analysis was determined in the freeze-dried plants of garlic, and the total carbohydrate content was calculated. The antioxidant activity and the content of selected polyphenolic compounds were also determined. Garlic cloves showed a higher content of dry matter, and total carbohydrates than the leaves of garlic plants. On the other hand, in the leaves, a significantly higher content of protein, total fat and ash were observed. Additionally, garlic leaves were characterised by a higher content of vitamin C, total polyphenols, and a higher antioxidant activity than garlic cloves. The leaves of young garlic plants from the May harvest were distinguished by a higher content of these compounds. The dominant phenolic compounds were catechin and epicatechin. The leaves of young plants can be a valuable source of bioactive substances, especially in early spring.

Waste Polyurethane Foams as Biomass Carriers in the Treatment Process of Domestic Sewage with Increased Ammonium Nitrogen Content.

In order to understand the mechanisms of microbial growth on waste polyurethane sponge materials, their effectiveness as biomass carriers in domestic sewage with increased ammonium nitrogen content treatment was assessed. Comparative experiments were carried out in microreactors under steady conditions of batch culture, which allowed for an assessment of different carriers, in the form of flexible foams, rigid foams, and flexible foams placed in full casings. In the studies conducted in continuous cultures, biomass carriers selected in batch culture were used as fillings in the column model. The structure of the microbial community inhabiting the spongy material was determined and the pollutant-removing process from real domestic sewage was assessed. Analyzes using the Illumina sequencing technique allowed for demonstrating that Nitrosomonas and Nitrospira were the predominant nitrifiers in the biomass carrier in the form of waste polyurethane foams (PUF). It was found that anammox bacteria, the presence of which-as unidentified Planctomycetes-was confirmed in the polyurethane sponge material, were also responsible for the high removal of N-NH4+. Burkholderia and Sphingopyxis phyla were identified as the dominant denitrifying bacteria involved in the treatment of domestic sewage with increased content of ammonium nitrogen. The biomass carrier in the form of waste PUF placed additionally in full casings proved to be more beneficial for the proliferation of bacteria involved in nitrification and denitrification processes. On the other hand, waste foams without casings proved to be more suitable for the growth of microorganisms known to perform partial denitrification and may accumulate nitrites (Staphylococcus, Dokdonella). Additionally, the presence of Devosia and Pseudonocardia, which participated in the phosphorus removal process, was found in the waste PUR foams.

Polyurethane Foams for Domestic Sewage Treatment.

The aim of the study was to assess the possibility of using polyurethane foams (PUF) as a filling of a foam-sand filter to directly treat domestic sewage with increased content of ammonium nitrogen and low organic carbon to nitrogen ratio (C/N). The study compared performance of two types of flexible foams: new, cylinder-shaped material (Novel Foams, NF) and waste, scrap foams (Waste Foams, WF). The foams serving as a filling of two segments of a foam-sand filter were assessed for their hydrophobic and physical properties and were tested for their cell structure, i.e., cell diameter, cell size distribution, porosity, and specific surface area. The study accounted also for selected application-related properties, such as hydrophobicity, water absorption, apparent density, dimensional stability, amount of adsorbed biomass, and the possibility of regeneration. Cell morphology was compared in reference foams, foams after 14 months of the filter operation, and regenerated foams. The experimental outcomes indicated WF as an innovative type of biomass carrier for treating domestic sewage with low C/N ratio. SEM images showed that immobilization of microorganisms in NF and WF matrices involved the formation of multi-cellular structures attached to the inner surface of the polyurethane and attachment of single bacterial cells to the foam surface. The amount of adsorbed biomass confirmed that the foam-sand filter made up of two upper layers of waste foams (with diameters and pore content of 0.50-1.53 mm and 53.0-63.5% respectively) provided highly favorable conditions for the development of active microorganisms.

Soft Sensor Application in Identification of the Activated Sludge Bulking Considering the Technological and Economical Aspects of Smart Systems Functioning.

The paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including: artificial neural networks, support vector machines, random forests, boosted trees, and logistic regression. The analysis conducted sought the combinations of independent variables for which the devised soft sensor is characterized with high accuracy and at a relatively low cost of determination. With the measurement results pertaining to the quantity and quality of wastewater as well as the temperature in the activated sludge chambers, a good fit can be achieved with the boosted trees method. In order to simplify the selection of an optimal method for the identification of activated sludge bulking depending on the model requirements and the data collected within the WWTP, an original system of weight estimation was proposed, enabling a reduction in the number of independent variables in a model-quantity and quality of wastewater, operational parameters, and the cost of conducting measurements.