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Two important flavonoids, kaempferol and quercetin possess remarkably potent biological impacts on human health. However, their structural complexity and low abundance in nature make both bulk chemical synthesis and extraction from native plants difficult. Therefore microbial production via heterologous expression of plant enzymes can be a safe and sustainable route for their production. Despite several attempts reported in microbial hosts, the production levels of kaempferol and quercetin still stay far behind compared to many other microbial-produced flavonoids. |
Extractive adsorption is an integrated separation method employing a novel resin with both particle and liquid characteristics in terms of adsorption and extraction. In this study, the novel extractive adsorption polystyrene-divinylbenzene (PS-DVB) macroporous resin was synthesized by suspension polymerization, in which n-octanol (OL-PS-DVB) or mixed alcohols of n-octanol, undecyl alcohol, and tetradecyl alcohol (MA-PS-DVB) were added as porogen and enclosed in the resin skeleton after the reaction. The characterization of the two novel resins of OL-PS-DVB and MA-PS-DVB showed that they have large specific surface areas of 48.7 and 17.4 m2/g, respectively. |
Vitamin K2 (VK2) is one of two natural forms of vitamin K, necessary for the proper functioning of organisms. Currently, it is sourced from chemical synthesis, nonetheless, it is worth reaching out to its natural sources. The aim of the study was to devise a voltammetric procedure for the determination of vitamin K2 (VK2) produced by bacteria in order to find the strain that exhibits the highest efficiency of VK2 production. Bacillus subtilis, isolated from traditional Japanese food (Nattō), was chosen as a model strain. Employment of the Controlled Growth Mercury Drop Electrode (CGMDE) was crucial, as it is the only electrode that allows performing the measurement on the surface specifically renewed directly before, thus minimizing the influence of interferents. |
In the present investigation, Na2O–CaO–SiO2–B2O3–Ag2O glasses were prepared using the traditional melt-quenching process, with Ag2O content progressively raised from 0 to 4 wt.%, at the expense of B2O3, in the chemical composition of these glasses. The created glasses’ physical, mechanical and electrical characteristics were measured. The bone bonding capacity of the as-prepared specimens was evaluated not only by in vitro studies with treatment in simulated body fluid but also by in vivo studies using the albino rat model at different time intervals up to 28 days. |
The semi-conductor SRDN-3a probe, an AlphaE detector with a silicon diode in a diffusion chamber, an AlphaGUARD monitor with an ionization chamber and CR-39 track detectors had been tested simultaneously in long-term measurements conducted in the technical corridor of Dobromierz dam. The passive detectors were exposed twice: for 56 days, and 117 days, others in parallel, with a 1-h data recording interval. The data distribution was tested with the Shapiro–Wilk test and outliers in the critical region were identified using Shewhart control charts. The correctness was evaluated by a z-score test recommended by the IAEA. The characteristics of outliers for each detectors are determined by the location of the critical region (a two-sided region and a positive skew). |
Laccases are multicopper enzymes that oxidize a wide range of aromatic and non-aromatic compounds in the presence of oxygen. The majority of industrially relevant laccases are derived from fungi and are produced in eukaryotic expression systems such as Pichia pastoris and Saccharomyces cerevisiae. Bacterial laccases for research purposes are mostly produced intracellularly in Escherichia coli, but secretory expression systems are needed for future applications. Bacterial laccases from Streptomyces spp. are of interest for potential industrial applications because of their lignin degrading activities. |
The direct binding of antiviral agents; Daclatasvir and valacyclovir and green synthesized nanoparticles to salmon sperm DNA have been assessed in a comparative study. The nanoparticles were synthesized by the hydrothermal autoclave method and have been fully characterized. The interactive behavior and competitive binding of the analytes to DNA in addition to the thermodynamic properties were deeply investigated by the UV–visible spectroscopy. The binding constants were monitored in the physiological pH conditions to be 1.65 × 106, 4.92 × 105 and 3.12 × 105 for daclatasvir,valacyclovir and quantum dots, respectively. The significant changes in the spectral features of all analytes have proven intercalative binding. The competitive study has confirmed that, daclatasvir, valacyclovir,... |
Simultaneous sensing of metabolic analytes such as pH and O2 is critical in complex and heterogeneous biological environments where analytes often are interrelated. However, measuring all target analytes at the same time and position is often challenging. A major challenge preventing further progress occurs when sensor signals cannot be directly correlated to analyte concentrations due to additional effects, overshadowing and complicating the actual correlations. In fields related to optical sensing, machine learning has already shown its potential to overcome these challenges by solving nested and multidimensional correlations. Hence, we want to apply machine learning models to fluorescence-based optical chemical sensors to facilitate simultaneous imaging of multiple analytes in 2D... |
In the present work, new Naproxen based 1,2,4-triazole-Schiff base derivatives have been synthesized and screened for in vitro antitumor activity and in silico pharmacokinetic studies. The structure of the newly synthesized compounds (5–12) was elucidated by IR, NMR and mass spectrometry. All the compounds were tested against breast MCF-7, hepatocellular Huh-7 and lung A-549 cancer cell lines using MTT assay. Compound 7 was better in killing A549 cells with IC50 3.71 µM (1.48 fold), compared with Doxorubicin (IC50 5.50 µM). Also, compound 7 was found to be non toxic on MRC-5 normal cells as it depicts IC50 more than 500 μM. Besides, compound 12 also revealed promising activity with IC50 6.94 and 3.33 µM against MCF-7 and Huh-7 respectively. |
Electroconductive scaffolds based on polyaniline (PANi)/polyacrylonitrile (PAN) were fabricated and surface-functionalized by carboxymethyl chitosan (CMC) as efficient scaffolds for nerve tissue regeneration. The results of scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and water contact angle measurement approved the successful fabrication of CMC-functionalized PANi/PAN-based scaffolds. Human adipose-derived mesenchymal stem cells (hADMSCs) were cultured on the scaffolds for 10 d in the presence or absence of β-carotene (βC, 20 µM) as a natural neural differentiation agent. The MTT and SEM results confirmed the attachment and proliferation of hADMSCs on the scaffolds. |
