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Abstract Cariprazine—the only single antipsychotic drug in the market which can handle all symptoms of bipolar I disorder—involves trans-4-substituted cyclohexane-1-amine as a key structural element. In this work, production of trans-4-substituted cyclohexane-1-amines was investigated applying transaminases either in diastereotope selective amination starting from the corresponding ketone or in diastereomer selective deamination of their diasteromeric mixtures. Transaminases were identified enabling the conversion of the cis-diastereomer of four selected cis/trans-amines with different 4-substituents to the corresponding ketones. In the continuous-flow experiments aiming the cis diastereomer conversion to ketone, highly diastereopure trans-amine could be produced (de > 99%). The yield of pure trans-isomers exceeding their original amount in the starting mixture could be explained by dynamic isomerization through ketone intermediates. The single transaminase-catalyzed process—exploiting the cis-diastereomer selectivity of the deamination and thermodynamic control favoring the trans-amines due to reversibility of the steps—allows enhancement of the productivity of industrial cariprazine synthesis.

Hermann’s tortoises (Testudo hermanni) are popular pets. Blood biochemistry is an essential tool for the early diagnosis of the diseases. The objective of the study was to investigate the biological variations in selected blood biochemical values in healthy tortoises through repeated samplings in the same animals. We also aimed to evaluate the values in time-related manner of sampling. Blood samples were taken five times (in two-month intervals) from the dorsal coccygeal vein. Twelve clinically healthy 2,5 year- old male tortoises were housed indoors. For each dataset, the mean, the standard deviation and the 95\% confidence interval of the mean were calculated. Mixed effect linear model was fitted with blood parameters as response variables, samples as fix factors and individuals as random factors. The mean levels and standard deviations are as follows: Ca, 2.3 ± 0.3 mmol/l; ionized Ca, 1.3 ± 0.4 mmol/l; P, 1.1 ± 0.3 mmol/l; uric acid, 121.1 ± 56.3 µmol/l; AST, 76.8 ± 42.8 IU/l; sodium, 127.7 ± 4.0 mmol/l; potassium, 4.5 ± 0.6 mmol/l. Except AST, sampling time had significant effect on the parameters. Despite the statistically significant difference between the collected samples, standard deviations were small in all samplings except for the uric acid. Accordingly, the clinical relevance of the sampling seems to be important especially for uric acid. In order to eliminate the possible effects of the time of sampling, repeated measurements are recommended if biochemical parameters are not in the reference intervals.

Several factors such as pathogen bacteria, or oral chemotherapy disturb the intestinal integrity, leading to several undesirable effects. Inactivated probiotics may be beneficial in safely redress the physiological functions of the intestinal epithelium. Our aim is to determine the effect of tyndallized Lactobacillus on LPS- and 5-fluorouracil-treated porcine jejunal cells. IPEC-J2 cells derived from porcine jejunal epithelium were used as the in vitro model. The enterocyte cell cultures were treated with 10 9 Lactobacillus reuteri cells/ml or 10 μg/ml lipopolysaccharides (LPS) or 100 μM 5-fluorouracil separately and simultaneously. We determined the alterations in mRNA levels of inflammatory mediators IL6, CXCL8/IL8, TNF. Furthermore, the protein level of IL-6 and IL-8 were measured. The fluorouracil treatment upregulated the IL6 gene expression, the endotoxin treatment upregulated the IL8 and TNF level. The heat-inactivated Lactobacillus increased the IL-8 level both at the gene expression and protein level. The co-administration of the non-viable probiotic with the 5-fluorouracil and the LPS resulted in decrease of IL6, IL8, and TNF level. The immune-modulator effect of tyndallized probiotic product is demonstrated in porcine jejunal cells. The inactivated Lactobacillus was able to prevent the accumulation of the selected inflammatory mediators in LPS- or 5-fluorouracil-exposed enterocytes., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Mycotoxins, present in a wide range of food and feed commodities, are toxic secondary metabolites produced by a number of different fungi. Certain mycotoxins do not readily degrade at high temperatures, therefore are resistant to food processing, and consequently are present in the human and animal food supply. Optical waveguide lightmode spectroscopy (OWLS) was applied for the detection of aflatoxin B1, in a competitive immunoassay format, to compare the analytical sensitivity achieved with an immunosensor design allowing signal enhancement by increasing the sensor surface through immobilization of gold nanoparticles (AuNPs) of different size and origin (obtained by chemical or biotechnological synthesis). The effects of AuNPs median size, the methods of sensitization and the biochemical parameters on immunosensor performace were examined. After optimization of the sensitized sensor surface, an immunosensing method was developed for the analysis of aflatoxin in paprika matrix and the results were compared with HPLC reference measurements., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

An improved sol-gel process involving the use of hollow silica microspheres as a supporting additive was applied for the co-immobilization of whole cells of Escherichia coli with Chromobacterium violaceum ω-transaminase activity and Lodderomyces elongisporus with ketoreductase activity. The co-immobilized cells with two different biocatalytic activities could perform a cascade of reactions to convert racemic 4-phenylbutan-2-amine or heptan-2-amine into a nearly equimolar mixture of the corresponding enantiomerically pure R amine and S alcohol even in continuous-flow mode. The novel co-immobilized whole-cell system proved to be an easy-to-store and durable biocatalyst., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A number of class I lyase-like enzymes, including aromatic ammonia-lyases and aromatic 2,3-aminomutases, contain the electrophilic 3,5-dihydro-5-methylidene-4H-imidazol-4-one (MIO) catalytic moiety. This study reveals that Pseudomonas fluorescens R124 strain isolated from a nutrient-limited cave encodes a histidine ammonia-lyase, a tyrosine/phenylalanine/histidine ammonia-lyase (XAL), and a phenylalanine 2,3-aminomutase (PAM), and demonstrates that an organism under nitrogen-limited conditions can develop novel nitrogen fixation and transformation pathways to enrich the possibility of nitrogen metabolism by gaining a PAM through horizontal gene transfer. The novel MIO enzymes are potential biocatalysts in the synthesis of enantiopure unnatural amino acids. The broad substrate acceptance and high thermal stability of PfXAL indicate that this enzyme is highly suitable for biocatalysis., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two ternary sol-gel matrices, an octyltriethoxysilane-based aliphatic matrix and a phenyltriethoxysilane (PTEOS)-based aromatic matrix, were used to immobilize a methanol-stable variant of lipase from Geobacillus stearothermophilus T6 for the synthesis of biodiesel from waste oil. Superior thermal stability of the mutant versus the wildtype in methanol was confirmed by intrinsic protein fluorescence measurements. The influence of skim milk and soluble E. coli lysate proteins as bulking and stabilizing agents in conjunction with sol-gel entrapment were investigated. E. coli lysate proteins were better stabilizing agents of the purified lipase mutant than skim milk, as evidenced by reverse engineering of the aromatic-based system. This was also shown for commercial Candida antarctica lipase B (CaLB) and Thermomyces lanuginosus lipase (TLL). Uniform, dense, and nonaggregated particles imaged by scanning electron microscopy and a small particle size of 13 μm pertaining to the system comprising PTEOS and E. coli lysate proteins correlated well with high esterification activity. Combining protein and immobilization engineering resulted in a durable biocatalyst with efficient recycling ability and high biodiesel conversion rates., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The MDR1 transporter mediated efflux of different xenobiotics out of the cells serves as the most important mechanisms of the multidrug resistance in cancer cells, thus inhibition of the MDR1 transporter may increase the efficiency of anticancer drugs in the therapy. Here we describe some new phenothiazine derivatives, which possess strong in vitro MDR1 inhibitory activity. The effectiveness of the compounds on the MDR1 mediated calcein-AM efflux, ATPase activity, and colchicine resistance was proven by microplate assays and flow cytometry using recombinant and control cell lines. Some of these derivatives were more active than verapamil and one of them was at least as active as cyclosporin A. According to our results the new structural elements built in these phenothiazine type compounds increased their MDR1 inhibitory activity, which may serve as a basis of the development of an effective MDR1 inhibitor drug.