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The aim of the study was to evaluate the effect of mineral-organic mixture on changes in the abundance of selected soil microorganisms. The experiment contained: soil with NPK (nitrogen, potassium, phosphorus) + 3 % or 6 % lignite (MF+CW3 %, MF+CW6 %) and 3 % zeolite-carbon composite (NaX-C); soil with NPK + 3 % or 6 % leonardite (MF+CL3 %, MF+CL6 %) and 3 % NaX-C; soil without fertilisation (C); soil fertilised with mineral NPK fertilisers (MF). Plants participating in the experiment were spring wheat and spring oilseed rape. The presence of the selected microorganisms was determined: Azotobacter spp., actinomycetes, ammonifiers, bacteria and mold fungi. Using Koch’s serial dilution method, the abundance of selected soil microorganisms was performed. The conducted research allows to conclude that the abundance of detected microorganisms depended on both the applied fertilisation and the plant grown. For the spring oilseed rape, the highest abundance of microorganisms was determined in treatments where fertilisation with lignite mixtures was applied, while for spring wheat, with leonardite mixtures. Increasing (from 3 % to 6 %) the share of lignite and leonardite in fertiliser mixtures did not translate into a proportional growth in the abundance of microorganisms, so such a treatment has no economic justification. Given their alkaline pH, the mixtures used can be a substitute for calcium fertilisers to improve soil properties and, consequently, protect soil organic matter from degradation.

Changes of the addition of poultry litter (PL) and poultry litter biochar (PLB) on quantitative and qualitative humus parameters in loamy sand were estimated during the 5-year study period. The following properties were determined in soil: pH, total carbon (Ctotal), total nitrogen (Ntotal), humic and fulvic acids, extracted carbon, and non-hydrolysing carbon. Additionally, light absorbance in the solutions of humic acids was computed at the wavelength of 280, 465, and 665 nm. It was demonstrated that organic matter mineralisation was most intense in soil with the addition of PL, causing significant quantitative and qualitative changes in humus compounds in soil. A slower rate of organic matter mineralisation was observed in soil amended with PLB, especially in a dose of 5.0 t ha−1, which indicated the long-term effect of this material on improving soil properties. Spectrophotometric indexes for the solution of humic acids also showed that PLB had a more favourable effect on the structure durability and lower mobility of humic acid carbon compared with PL. The application of PL and PLB significantly increased the non-hydrolysing carbon content in soil, indicating greater stabilisation of humus compounds and, at the same time, lower CO2 emissions. It was found that the addition of organic materials to soil significantly increased the soil organic carbon contents. Our study has shown that the identification of changes that may occur in the quantitative and qualitative composition of soil humus after the application of PLB may be helpful in determining the appropriate biochar dose.

New ways of managing hop sediments from brewing and fermentation of beer are constantly being sought and the existing ones improved as part of the circular economy. These wastes are not generated in large amounts, but the absence of their proper characteristics may lead to further processing errors. The study analyses the composting of hop waste under laboratory conditions and the effects of the biological activity of composts introduced into the soil. The study was carried out on two-hop sediments from two different technological stages of beer production: hot trub (HT) and spent hops (SH). Chemical, microbiological and biochemical analyses, as well as the assessment of phytotoxicity to Lepidium sativum L., were performed in the materials. The results proved that, due to their formation technology, the tested feedstocks are safe from an epidemiological point of view and are not a source of microbial contamination. Inhibitory properties for plant development were found for HT and it most likely results from the organic compound content. The mineral composition of hot trub does not exclude composting if its share in biomass is low. Spent hops (SH) were characterised by a significant total nitrogen content, which affected the composting process. Composting this sediment required the selection of substrates with a wide C:N ratio. The number of microorganisms inhabiting the analysed material was very diverse and varied depending on the type of sediments. The sample that contained the composted SH from dry hopping had a much larger number of microorganisms than the sample with HT from wet hopping.

Waste fly ash, with both low (with the addition of vermiculite) and high contents of unburned coal, were subjected to hydrothermal syntheses aiming to obtain zeolite composite materials—zeolite + vermiculite (NaX–Ver) and zeolite + unburned carbon (NaX–C). The composites were compared with parent zeolite obtained from waste fly ash with a low content of unburned carbon (NaX–FA). In this study, the physicochemical characteristics of the obtained materials were evaluated. The potential application of the investigated zeolites for the adsorption of ammonium ions from aqueous solutions was determined. Composite NaX–Ver and parent zeolite NaX–FA were characterized by comparable adsorption capacities toward ammonium ions of 38.46 and 40.00 mg (NH4+) g−1, respectively. The nearly 2-fold lower adsorption capacity of composite NaX–C (21.05 mg (NH4+) g−1) was probably a result of the lower availability of ion exchange sites within the material. Adsorbents were also regenerated using 1 M NaCl solution at a pH of 10 and subjected to 3 cycles of adsorption–desorption experiments, which proved only a small reduction in adsorption properties. This study follows the current trend of waste utilization (fly ash) and the removal of pollutants from aqueous solutions with respect to their reuse, which remains in line with the goals of the circular economy.

The availability and affordability of fertilizers are the main risks currently faced by the fertilizer market. Therefore, there is a need to look for other sources of nutrient supply for plants, while taking care of soil properties. The application of fertilizers with the addition of functionalized materials could help in the efficient use of nutrients. The aim of the study was to assess the impact of the application of mixtures with the addition of zeolite–vermiculite composites (NaX–Ver) on the culturable microorganisms and selected soil properties. A two-year pot experiment was conducted on soil with elevated contents of cadmium, zinc, and lead. The test treatments included soil mixed with NPK and additives in two doses of NaX–Ver combined with leonardite (Leo) or lignite (L). The test plant used in the experiment was maize. The soil material was analyzed for the number of bacteria, mold fungi, actinomycetes, and ammonifiers. Furthermore, soil pH, EC, N total, and SOC contents, as well as soil respiration activity, were tested. The applied fertilizer mixtures had a great effect on changes in the N total and SOC contents. The N total increase was 45.5% in NaX–Ver3%L3% and 51% in NaX–Ver9%Leo6%, and the largest SOC increase (24.3%) was recorded in the NaX–Ver3%Leo3% treatment. The highest respiration activity was determined in NaX–Ver3%Leo3% and NaX–Ver9%Leo6%: 2.12 µg C-CO2 g−1 DM h−1 and 2.14 µg C-CO2 g−1 DM h−1, respectively. A significant correlation between pH values and the number of culturable microorganisms was found. The number of soil microorganisms depended on the type of fertilization used. The best stimulation of the number of culturable soil microorganisms was found in treatments with the addition of 3% of L or Leo in combination with NaX–Ver. The percentage increases in the number of the analyzed culturable microorganisms after the application of leonardite-based fertilization in combination with the zeolite–vermiculite composite were, on average: bacteria, 1096%; mold fungi, 1529%; actinomycetes, 1477%; ammonifiers, 910%.

Environmental protection, including rational waste management, is one of the main goals of sustainable development. Scientists are continuously searching for new approaches and solutions to counteract an increasing environmental pollution. Zeolites, due to their unique properties are a subject of an ongoing scientific research for applications as adsorbents and ion exchangers in numerous areas of agriculture and environmental protection. In agriculture, studies mainly concentrate around the application of natural zeolite which can be a useful soil conditioner and an additive to fertilizer. However, the main focus of attention in the environmental remediation is currently on synthesized zeolites. Because the main product of coal combustion, namely fly ash, exhibits similar chemical composition to a zeolite, it is a promising low-cost material for their synthesis. Although numerous papers have been published regarding zeolites’ application in agriculture and environmental protection, their great potential has not been fully explored yet. This review presents state-of-art achievements in synthesis and modifications of zeolites and also an overview of their application in agricultural production and protection of water, air, and soil. Issues relating to cost of regeneration of zeolite adsorbents, estimated costs of their mining and production from fly ash are also discussed.

Gastroesophageal reflux disease (GERD) is a common problem that occurs in both adult and pediatric populations and can significantly degrade patients' quality of life and lead to life-threatening complications. A prudent course of management in a patient with classic GERD symptoms would be to empirically prescribe lifestyle modifications and a proton pump inhibitor (PPI) for six to eight weeks. Osteopathic manipulative treatment may also be a useful adjunct. If the patient is unable to afford a PPI, a histamine type-2 receptor antagonist may be substituted (although they are much less effective). If resolution of symptoms occurs, the therapeutic response can confirm the diagnosis of uncomplicated GERD. If the patient has recurrent or intractable symptoms, the next step would be to order pH monitoring, manometry, or endoscopic evaluation of the esophagus and stomach (esophagogastroduodenoscopy [EGD]). If there are any atypical symptoms such as persistent cough, asthma, melena, sore throat, or hoarse voice, EGD should be ordered immediately. Patients with chronic esophagitis or extra-esophageal symptoms who have failed (or refused) medical management should consider fundoplication.

A recently reported dual LPA1/LPA3 receptor antagonist (1) has been modified so as to modulate the basicity, sterics, and dipole moment of the 2-pyridyl moiety. Additionally, the implications of installing nonhydrolyzable phosphate head group isosteres with regard to antagonist potency and selectivity at LPA receptors is described. This study has resulted in the development of the first nonhydrolyzable and presumably phosphatase-resistant LPA3-selective antagonist reported to date.

A recently reported dual LPA1/LPA3 receptor antagonist (VPC12249, 1) has been modified herein so as to optimize potency and selectivity at LPA receptors. Compounds containing variation in the acyl lipid chain and linker region have been synthesized and screened for activity at individual LPA receptors. LPA1-selective (14b) and LPA3-selective (10g,m) compounds of modest potency have been discovered. Additionally, 2-pyridyl derivative 10t exhibits a Ki value of 18 nM at the LPA1 receptor and is significantly more potent than 1 at the LPA3 receptor. This paper describes the synthetic methods, biological evaluation, and structure-activity relationships (SARs) of LPA receptor antagonists.

Mild trypsin proteolysis (enzyme concentration 0.05% at 15°C, pH 7.4; mixing 30 min at 20 rpm) of bream mince improved mince susceptibility to freeze texturization. Formation of porous-fibrous texture of heat-set, freeze-texturized minces was associated with strong fragmentation of myosin heavy chain (MHC), decrease in extractability of myofibrillar protein and increased insoluble protein and thermal drip. Some deamidation of protein was also observed. We concluded that limited trypsin proteolysis accelerated transglutaminase mediated cross-linking of protein by acyl transfer reactions. Protein polymerization through plastein reactions and intermolecular hydrophobic interaction probably also occurred.

Lysophosphatidic acid (LPA) is a bioactive lysophospholipid mediator that acts through G protein-coupled receptors. Most cell lines in culture express one or more LPA receptors, making it difficult to assign a response to specific LPA receptors. Dissection of the signaling properties of LPA has been hampered by lack of LPA receptor subtype-specific agonists and antagonists. The present study characterizes an ester-linked thiophosphate derivative (1-oleoyl-2-O-methyl-rac-glycerophosphothionate, OMPT) of LPA. OMPT is a functional LPA analogue with potent mitogenic activity in fibroblasts. In contrast to LPA, OMPT does not couple to the pheromone response through the LPA(1) receptor in yeast cells. OMPT induces intracellular calcium increases efficiently in LPA(3) receptor-expressing Sf9 cells but poorly in LPA(2) receptor-expressing cells. Guanosine 5'-O-(3-[(35)S]thio)triphosphate binding assays in mammalian cells showed that LPA exhibits agonistic activity on all three LPA receptor subtypes, whereas OMPT has a potent agonistic effect only on the LPA(3) receptor. In transiently transfected HEK293 cells, OMPT stimulates mitogen-activated protein kinases through the LPA(3) but not the LPA(1) or LPA(2) receptors. Furthermore, OMPT-induced intracellular calcium mobilization in mammalian cells is efficiently inhibited by the LPA(1)/LPA(3) receptor-selective antagonist VPC12249. These results establish that OMPT is an LPA(3)-selective agonist. OMPT binding to the LPA(3) receptor in mammalian cells is sufficient to elicit multiple responses, including activation of G proteins, calcium mobilization, and activation of mitogen-activated protein kinases. Thus OMPT offers a powerful probe for the dissection of LPA signaling events in complex mammalian systems.