Growth Medium Research Articles

3D- printed modular spr platform integrated with ellipsometer for in-situ label-free optical sensing applications

The present work focuses on advancing optical sensing abilities through the instrumentation of Surface Plasmon Resonance Spectroscopy (SPR) with a commercial ellipsometer. This approach involves the incorporation of an in-house-built 3D-printed SPR module to circumvent the complexity of optical alignments with the ellipsometer. Currently, no commercially available SPR-enhanced Ellipsometry (SPRE) system exists, and previous systems are mostly custom-designed. Our work addresses this gap by introducing an in-house-built SPR module compatible with Ellipsometry and constructed using 3D printing technology. The 3D-printed SPR module is user-friendly, durable, lightweight, and cost-effective, incorporating a flow cell crucial for liquid media operation. This integrated tool provides a highly surface-sensitive, non-invasive, and label-free optical sensing platform. The developed SPR-Ellipsometry platform demonstrates excellent performance in detecting biochemical analytes and multilayer adsorption of poly-electrolytes. The bulk refractive index sensitivity measurement was performed to calibrate the Au sensor chip. The Wavelength (SPR mode), amplitude (Ψ), and phase interrogation (∆) exhibit bulk refractive index sensitivities of 3098 ± 177 nm/RIU, 835 ± 22 °/RIU and 5839 ± 229 °/RIU, respectively. We obtained the refractive index resolution around 1.712 × 10−7 RIU. Protein-protein (BSA/Anti-BSA) interactions were also conducted, achieving a detection limit of 3 pM for Anti-BSA. This work will significantly expand the functionality of SPRE sensors by offering enhanced sensitivity, rich information, and high precision, as well as opening avenues for more efficient and accessible optical sensing technologies. Moreover, the study establishes a foundational framework for researchers, shedding light on the potential of 3D printers in laboratories and expediting the development of cost-effective integrated sensing platforms.

MicroRNA-513b-5p inhibits epithelial mesenchymal transition of colon cancer stem cells through IL-6/STAT3 signaling pathway

ObjectiveTo reveal the mechanisms by which miR-513b-5p inhibits metastasis of colon cancer stem cells (CCSCs) through IL-6/STAT3 in HCT116 cells.MethodsSphere formation media and magnetic cell sorting were used to enrich and screen CCSCs. We used a colony formation assay, cell proliferation and viability assays, and a nude mouse transplantation tumor assay to identify CCSCs. ELISA was performed to identify IL-6 in the cell culture medium, and the growth, viability, wound healing, and transwell migration of distinct cell groups were compared to differentiate them. Dual-luciferase reporter assay, RT-PCR, and/or Western Blot analysis were conducted to determine the correlation between them.ResultsCD133+CD44+ HCT116 cells were shown to have higher cloning efficiency, greater proliferation ability and viability, and stronger tumorigenicity. A dual-luciferase reporter assay revealed that miR-513b-5p negatively affected STAT3 expression. RT-PCR and/or Western Blot analysis suggested that miR-513b-5p negatively affected STAT3 and Vimentin, while positively affecting E-cadherin expression. The STAT3 overexpression vector + miR-513b-5p inhibitor cell group had the highest efficiency, greatest proliferation ability and viability, and the highest IL-6 level in the experiments.ConclusionsMir-513b-5p inhibited the epithelial-mesenchymal transition (EMT) of CCSCs through IL-6/STAT3. This potential mechanism may provide a new therapeutic target for colon cancer.

Piggybacking functionalized DNA nanostructures into live-cell nuclei.

DNA origami nanostructures (DOs) are promising tools for applications including drug delivery, biosensing, detecting biomolecules, and probing chromatin substructures. Targeting these nanodevices to mammalian cell nuclei could provide impactful approaches for probing, visualizing, and controlling biomolecular processes within live cells. We present an approach to deliver DOs into live-cell nuclei. We show that these DOs do not undergo detectable structural degradation in cell culture media or cell extracts for 24 hours. To deliver DOs into the nuclei of human U2OS cells, we conjugated 30-nanometer DO nanorods with an antibody raised against a nuclear factor, specifically the largest subunit of RNA polymerase II (Pol II). We find that DOs remain structurally intact in cells for 24 hours, including inside the nucleus. We demonstrate that electroporated anti-Pol II antibody-conjugated DOs are piggybacked into nuclei and exhibit subdiffusive motion inside the nucleus. Our results establish interfacing DOs with a nuclear factor as an effective method to deliver nanodevices into live-cell nuclei.

Generation of nano-to-microplastics from polypropylene surfaces via femtosecond laser ablation in liquids with different viscosities

Preparation of polypropylene (PP) nano and microparticles, crucial for investigating the effects of plastics on both human health and the environment, presents a significant and immediate challenge. Utilizing an fs laser system in different liquid mediums such as water, dodecane, and hexadecane, we have successfully generated PP particles with sizes ranging from 1.8 to 4911 nm. This outcome is partly attributed to the constraint on plasma expansion caused by the viscosity of the liquid media. We investigated the areas of material removal and observed a transition from ordered to disordered removal patterns during this process. The formation of filaments and pillars within the material removal cavity, along with the deposition layer at the cavity edge, primarily occurred due to insufficient plasma formation at low laser energy levels. Furthermore, we observed neck-shaped filaments and nano cracks on the deposition surface, which were attributed to the heat effect during laser interaction with the PP substrate. Moreover, we collected distinct nano-Fourier transform infrared spectroscopy (FTIR) signals from both the nanoparticle area and the deposition layer, revealing a 2 cm−1 wavenumber difference between the two regions. This discrepancy proved to be a valuable method for distinguishing between the nanoparticle area and the deposition layer.

In vitro cultivation of adherent cells on microscope slides for downstream applications

In vitro studies with cultured cells are often conducted as an important part of basic research. Adherent cells are typically cultivated in flasks or trays, for which cell staining and subsequent visualization become impractical. We here present a simple step-by-step method for growing adherent cells directly on glass microscope slides, using low-cost equipment readily available in most laboratories. Most parameters such as type of microscope slide (e.g. surface coating), cell seeding concentrations and incubation times can be adjusted according to cell line characteristics and experimental aims, reflecting the methods’ flexibility. Through our experiments, microscope slides proved to provide an acceptable surface for cell adhesion and growth of the tested cell lines, as well as being robust and functional with respect to downstream procedures. The method can potentially be combined with different techniques for visualization of experimental effects, such as histological staining methods, fluorescent staining, and immunochemistry. In our method development we have successfully cultivated three different cell lines directly on microscope slides – Atlantic salmon kidney cells (ASK), rainbow trout gill cells (RTgill-W1), and human cancerous lung cells (A549) – and subjected them to various experimental treatments. Finally, as proof-of-concept we provide examples of successful histological staining of the fixed cells.Experimental design in short:•Cultivate cells and calculate cell concentration•Seed a small volume of growth medium with an appropriate number of cells on microscope slide in an area confined by hydrophobic marker•Let cells adhere over night before adding more growth medium or directly conducting experiments and fixing cells for downstream applications

Enhanced biodegradation of benzo[a]pyrene with Trametes versicolor stimulated by citric acid.

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants with carcinogenic, mutagenic and teratogenic effects. The white-rot fungi in the fungal group have significant degradation ability for high molecular weight organic pollutants. However, exogenous fungi are easily antagonized by indigenous microorganisms. Low molecular weight organic acids, a small molecular organic matter secreted by plants, can provide carbon sources for soil microorganisms. Combining organic acids with white rot fungi may improve the nutritional environment of fungi. In this study, immobilized Trametes versicolor was used to degrade benzo[a]pyrene in soil, and its effect on removing benzo[a]pyrene in soil mediated by different low molecular weight organic acids was investigated. The results showed that when the degradation was 35days, the removal effect of the experimental group with citric acid was the best, reaching 43.7%. The degradation effect of Trametes versicolor on benzo[a]pyrene was further investigated in the liquid medium when citric acid was added, and the effects of citric acid on the biomass, extracellular protein concentration and laccase activity of Trametes versicolor were investigated by controlling different concentrations of citric acid. In general, citric acid can act as a carbon source for Trametes versicolor and promote its extracellular protein secretion and laccase activity, thereby accelerating the mineralization of benzo[a]pyrene by Trametes versicolor. Therefore, citric acid can be used as a biostimulant in the remediation of PAHs contaminated soil with Trametes versicolor.

Extractive Mass Transfer of Zr(IV) into a Hydrophobic Ionic Liquid Medium Containing Diglycolamide Extractant: Solvent Extraction and Spectroscopic Analysis.

Solvent extraction of Zr(IV) in ionic liquid (IL) medium is less known and Zr(IV) - IL chemistry indeed needs exploration to realize the coordination approach of Zr(IV) in IL phase. In view of this, in the present work, a strongly hydrophobic imidazolium based IL: 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide ([C8mim][NTf2]) as the medium containing a diglycolamide (DGA) extractant: N,N,N',N'-tetra-n-octyldiglycolamide (TODGA) was opted to understand the extraction behavior of Zr(IV) from nitric acid medium. Different experimental parameters such as the concentration of initial nitric acid, initial feed metal concentration, equilibration time and ligand concentration were tuned to unravel the extraction efficiency of the proposed IL phase towards Zr(IV). The extraction scenario was completely dependent on the hydrophobicity of IL diluent and increasing extraction trend with an increase in feed acidity along with the coordination of two TODGA molecules ensured Zr(IV) - complex formation in a neutral solvation mechanistic pathway. The extraction trend of Zr(IV) was compared with molecular diluent (n-dodecane (n-DD)) containing TODGA and a phase modifier: N,N-dihexyloctanamide (DHOA). The coordination aspect of Zr(IV) with ligand in IL phase was ascertained spectroscopically to validate Zr(IV) loading in IL phase. Thermodynamics of Zr(IV) extraction revealed the nature of the extraction process and the complex formation.

Feasibility of composted green waste amended by vermiculite and earthworm casts as the growth media for three common ornamental plants.

This study demonstrated the effects of adding specific proportions of vermiculite (VMT: 0%, 10%, and 20%) and earthworm casts (EWCs: 0%, 10%, and 20%) on the physico-chemical properties of composted green waste (CGW), and the impacts of amended CGW as growth media on the growth of three common ornamental plants (Dahlia pinnata Cav. [dahlia], Centaurea cyanus L. [cornflower], and Consolida ajacis[L.] Schur [delphinium]). Compared with Treatment T1 (CK), the addition of 10% VMT and 20% EWCs greatly (p < 0.05) increased the total porosity, aeration porosity, water-holding porosity, total nitrogen, available phosphorus, available potassium, and organic matter of CGW by 9%, 35%, 4%, 18%, 27%, 13%, and 33%, respectively. In addition, this pattern increased (p < 0.05) the total fresh biomass, total chlorophyll content, and root length of dahlias by 9%, 19%, and 27%, respectively; those of cornflowers by 17%, 30%, and 29%, respectively (p < 0.05); and those of delphiniums by 23%, 14%, and 63%, respectively. Therefore, the amended CGW supplemented with 10% VMT and 20% EWCs was an ideal growth medium for the three plants.

Effects of producing high levels of hyperthermophile-specific C25,C25-archaeal membrane lipids in Escherichia coli

A hyperthermophilic archaeon, Aeropyrum pernix, synthesizes C25,C25-archaeal membrane lipids, or extended archaeal membrane lipids, which contain two C25 isoprenoid chains that are linked to glycerol-1-phosphate via ether bonds and are longer than the usual C20,C20-archaeal membrane lipids. The C25,C25-archaeal membrane lipids are believed to allow the archaeon to survive under harsh conditions, because they are able to form lipid membranes that are impermeable at temperatures approaching the boiling point. The effect that C25,C25-archaeal membrane lipids exert on living cells, however, remains unproven along with an explanation for why the hyperthermophilic archaeon synthesizes these specific lipids instead of the more common C20,C20-archaeal lipids or double-headed tetraether lipids. To shed light on the effects that these hyperthermophile-specific membrane lipids exert on living cells, we have constructed an E. coli strain that produces C25,C25-archaeal membrane lipids. However, a resultant low level of productivity would not allow us to assess the effects of their production in E. coli cells. Herein, we report an enhancement of the productivity of C25,C25-archaeal membrane lipids in engineered E. coli strains via the introduction of metabolic pathways such as an artificial isoprenol utilization pathway where the precursors of isoprenoids are synthesized via a two-step phosphorylation of prenol and isoprenol supplemented to a growth medium. In the strain with the highest titer, a major component of C25,C25-archaeal membrane lipids reached ∼11 % of total lipids of E. coli. It is noteworthy that the high production of the extended archaeal lipids did not significantly affect the growth of the bacterial cells. The permeability of the cell membrane of the strain became slightly lower in the presence of the exogenous membrane lipids with longer hydrocarbon chains, which demonstrated the possibility to enhance bacterial cell membranes by the hyperthermophile-specific lipids, along with the surprising robustness of the E. coli cell membrane.

P-190 Impact of low lactate culture media in embryo development and IVF outcomes

Abstract Study question Can low lactate culture media improve embryo utilization rate in artificial reproductive technology (ART) cycles? Summary answer Embryos cultured in low lactate media showed a significant improved blastocyst utilization rate compared to embryos cultured in standard culture media. What is known already Culture media plays a key role in the embryonic development in the IVF lab. Currently, different culture medias are commercially available, yet no consensus on the most suitable media composition has been reached. Recently, minimizing metabolic stress for the embryo to enhance implantation and pregnancy rates has been suggested. Research on the metabolism of mammalian preimplantation embryos revealed that excess lactate in the culture medium, in addition to pyruvate and glucose, can burden metabolic efficiency, as embryos naturally produce lactate during energy production. Study design, size, duration The prospective, monocentric study was designed and conducted at the Kinderwunsch Institut Schenk GmbH (Dobl, Austria). A total of 60 women with an average age of 32.5 undergoing ICSI (intracytoplasmic sperm injection) treatment were included. All of them had at least 6 mature (MII) oocytes at time of insemination. Sibling oocytes were cultured in two different culture medias and outcomes were compared. Patients undergoing preimplantation genetic testing were excluded. Participants/materials, setting, methods Mature (MII) oocytes of each patient (total 621 MII oocytes) were inseminated by ICSI and then equally split into two culture medias: standard (313 oocytes) and low lactate (308 oocytes) covered with mineral-oil overlay and incubated in time-lapse under the same conditions. A total of 428 embryos were obtained. Embryos were evaluated using morphokinetic criteria. The fertilization rate, embryo utilization rate, pregnancy rate and time to Blastocyst were analyzed. Main results and the role of chance No differences were observed in the number of fertilized oocytes (n = 211 and 217 in the standard and low lactate media, respectively). The overall embryo utilization rate was significantly different (p &amp;lt; 0.008) resulting in 52% in standard media and 64.3% using low lactate media. Interestingly, age stratification (18-30; 31-35; 36-41) revealed overall higher embryo utilization rates when using low lactate media in all age groups. Blastocyst utilization rate was significantly different (p &amp;lt; 0.007) 43,1% and 58,05% in the standard and low lactate media, respectively. Regarding the time to blastocyst, it was observed that in the standard culture media 80% of the blastocysts reached blastocyst stage on D + 5 whereas in the low lactate media 92,07% reached blastocyst stage on D + 5, which was also significantly different (p &amp;lt; 0.001). No differences in pregnancy and live birth rates were observed. Limitations, reasons for caution The number of patients may be seen as a study limitation. Results should be confirmed with a bigger sample size. Wider implications of the findings Low lactate media could help improve IVF outcomes due to higher embryo utilization rate leading to better cumulative pregnancy rates. Excessive lactate concentration in culture media could negatively influence embryo metabolism. Trial registration number not applicable

Development and Validation of Liquid Chromatographic Method for Fast Determination of Lincomycin, Polymyxin and Vancomycin in Preservation Solution for Transplants.

In this study, a liquid chromatographic method was developed for the fast determination of lincomycin, polymyxin and vancomycin in a preservation solution for transplants. A Kinetex EVO C18 (150 × 4.6 mm, 2.6 µm) column was utilized at 45 °C. Gradient elution was applied using a mixture of mobile phases A and B, both including 30 mM phosphate buffer at pH 2.0 and acetonitrile, at a ratio of 95:5 (v/v) for A and 50:50 (v/v) for B. A flow rate of 1.0 mL/min, an injection volume of 20 µL and UV detection at 210 nm were used. A degradation study treating the three antibiotics with 0.5 M hydrochloric acid, 0.5 M sodium hydroxide and 3% H2O2 indicated that the developed method was selective toward lincomycin, polymyxin, vancomycin and their degradation products. Other ingredients of the preservation solution, like those from the cell culture medium, did not interfere. The method was validated with good sensitivity, linearity, precision and accuracy. Furthermore, lincomycin, polymyxin and vancomycin were found to be stable in this preservation solution for 4 weeks when stored at -20 °C.

Response of wheat (Triticum aestivum L. cv.) to the coexistence of micro-/nanoplastics and phthalate esters alters its growth environment

Micro- and nano-plastics (MPs/NPs) have emerged as a global pollutant, yet their impact on the root environment of plants remains scarcely explored. Given the widespread pollution of phthalate esters (PAEs) in the environment due to the application of plastic products, the co-occurrence of MPs/NPs and PAEs could potentially threaten the growth medium of plants. This study examined the combined effects of polystyrene (PS) MPs/NPs and PAEs, specifically dibutyl phthalate and di-(2-ethylhexyl) phthalate, on the chemical properties and microbial communities in a wheat growth medium. It was observed that the co-pollution with MPs/NPs and PAEs significantly increased the levels of oxalic acid, formic acid, and total organic carbon (TOC), enhanced microbial activity, and promoted the indigenous input and humification of dissolved organic matter, while slightly reducing the pH of the medium solution. Although changes in chemical indices were primarily attributed to the addition of PAEs, no interaction between PS MPs/NPs and PAEs was detected. High-throughput sequencing revealed no significant change in microbial diversity within the media containing both PS MPs/NPs and PAEs compared to the media with PS MPs/NPs alone. However, alterations in energy and carbohydrate metabolism were noted. Proteobacteria dominated the bacterial communities in the medium solution across all treatment groups, followed by Bacteroidetes and Verrucomicrobia. The composition and structure of these microbial communities varied with the particle size of the PS in both single and combined treatments. Moreover, variations in TOC, oxalic acid, and formic acid significantly influenced the bacterial community composition in the medium, suggesting they could modulate the abundance of dominant bacteria to counteract the stress from exogenous pollutants. This research provides new insights into the combined effects of different sizes of PS particles and another abiotic stressor in the wheat root environment, providing a critical foundation for understanding plant adaptation in complex environmental conditions.

Исследование нативной микробиоты рапсового жмыха – потенциального источника промышленных продуцентов

Rapeseed oil production is very active in Russia. Its main by-product is cake: its chemical composition and availability make it an excellent source of nutrients in microbial cultivation to be used as biologically active compounds or as part of functional products. The research objective was to study the native microbiota of rapeseed cake under conditions of high humidity, as well as to describe the morphology of isolated microorganisms and determine their genera by NGS sequencing. The study featured rapeseed cake and microbial colonies isolated after 2, 5, 7, and 9 days of fermentation. The microbial isolates were obtained by the method of surface and deep cultivation on solid and liquid nutrient media, respectively. The metagenomic analysis of the microbial taxonomy involved sequencing on the Illumina platform. The experiment revealed 16 types of colonies with different morphology. Colonies with morphology 1, 3, 8, 12, and 13 were predominant for all fermentation periods, which means that they grew as isolates during the liquid-phase fermentation. The metagenomic analysis revealed at least 28 genera of bacteria in the rapeseed cake suspensions. The highest percentage belonged to Weisella (≤ 45.8% on day 2), Acinetobacter (≤ 40.6% on day 7), Lactobacillus (≤ 15.7% on day 5), Leuconostoc (≤ 15.1% on day 7), Enterococcus (≤ 14.6% on day 5), and Paenibacillus (≤ 16.3% on day 9). The obtained isolates could be of interest as industrial producers of useful metabolites, e.g., enzymes, pigments, organic acids, etc. Further research will identify the microbial species, their useful properties, and optimal cultivation conditions.

Electromigrated Gold Nanogap Tunnel Junction Arrays: Fabrication and Electrical Behavior in Liquid and Gaseous Media.

Tunnel junctions have been suggested as high-throughput electronic single molecule sensors in liquids with several seminal experiments conducted using break junctions with reconfigurable gaps. For practical single molecule sensing applications, arrays of on-chip integrated fixed-gap tunnel junctions that can be built into compact systems are preferable. Fabricating nanogaps by electromigration is one of the most promising approaches to realize on-chip integrated tunnel junction sensors. However, the electrical behavior of fixed-gap tunnel junctions immersed in liquid media has not been systematically studied to date, and the formation of electromigrated nanogap tunnel junctions in liquid media has not yet been demonstrated. In this work, we perform a comparative study of the formation and electrical behavior of arrays of gold nanogap tunnel junctions made by feedback-controlled electromigration immersed in various liquid and gaseous media (deionized water, mesitylene, ethanol, nitrogen, and air). We demonstrate that tunnel junctions can be obtained from microfabricated gold nanoconstrictions inside liquid media. Electromigration of junctions in air produces the highest yield (61-67%), electromigration in deionized water and mesitylene results in a lower yield than in air (44-48%), whereas electromigration in ethanol fails to produce viable tunnel junctions due to interfering electrochemical processes. We map out the stability of the conductance characteristics of the resulting tunnel junctions and identify medium-specific operational conditions that have an impact on the yield of forming stable junctions. Furthermore, we highlight the unique challenges associated with working with arrays of large numbers of tunnel junctions in batches. Our findings will inform future efforts to build single molecule sensors using on-chip integrated tunnel junctions.

Pyrobacteriopheophorbide-a derivatives possessing various hydrophilic esterifying groups at the C17-propionate residues for photodynamic therapy.

Aiming at the application to photodynamic therapy, natural bacteriochlorophyll-a was converted to chemically stable free-base derivatives possessing different kinds of hydrophilic C17-propionate residues. These semi-synthetic bacteriochlorins were found to have self-assembling ability in an aqueous environment and formed stable J-type aggregates in a cell culture medium containing 0.2% DMSO. The electronic absorption spectra of all the sensitizers showed Qy absorption maxima at 754 nm in DMSO as their monomeric states, while a drastic shift of the red-most bands to ca. 880 nm was observed in the aqueous medium. The circular dichroism spectra in the medium showed much intense signals compared to those measured in DMSO, supporting the formation of well-ordered supramolecular structures. By introducing hydrophilic side chains, the bacteriochlorin sensitizers could be dispersed in the aqueous medium as their J-aggregates without the use of any surfactants. Cellular uptake efficiencies as well as photodynamic activities were evaluated using human cervical adenocarcinoma HeLa cells. Among the 11 photosensitizers investigated, the best result was obtained for a charged derivative possessing trimethylammonium terminal (17-CH2CH2COOCH2CH2N+(CH3)3I-) and photocytotoxicity of EC50 = 0.09 μM was achieved by far-red light illumination of 35 J/cm2 from an LED panel (730 nm).

Isolation, identification, biological characteristics, and pathogenicity of an entomogenous fungus against the Egyptian mealybug, Icerya aegyptiaca (J.) (Hemiptera: Monophlebidae)

BackgroundIn this study, an entomogenous, fungus was isolated from the Egyptian mealybug, Icerya aegyptiaca (J.) (Hemiptera: Monophlebidae) on the parasol leaf tree, Macaranga tanarius, in China where evaluated as a biocontrol fungus to reduce the population of the target insect. The strain was identified as Aspergillus parasiticus by morphological and phylogenetic analysisand named ZHKUAP1. The biological characteristics, pathogenicity, and field control effect of the strain were determined.ResultsThe most suitable medium for the mycelial growth of strain ZHKUAP1 was PPDA medium, with an optimum temperature of 30 °C and pH 7, in addition to glucose and peptone as carbon and nitrogen sources. The optimum sporulation conditions were the PPDA medium at 30 °C and pH 6, using the soluble starch and beef extract as carbon and nitrogen sources. The mycelial growth and spore production of strain ZHKUAP1 were stopped at 70 °C and above, indicating that it was not resistant to high temperatures. High concentrations of spore suspension, against young insect age, resulted high corrected mortality, as well as decreased the median lethal time. When the spore concentration was 1 × 108 cfu/ml, the corrected mortality of the second nymph was 88.33%, and the LT50 was 0.66 day. After 10 days of inoculation, the LC50 of the second instar nymph was the smallest, reaching 4.07 × 104 cfu/ml. On the 10th day of the field experiment, the corrected mortality was 76.45%, indicating that the A. parasiticus strain ZHKUAP1 had strong pathogenicity on I. aegyptiaca population.ConclusionsThe indoor toxicity of the strain to I. aegyptiaca was determined, and the field control effect of the pathogen was explored on this basis. The results have important application prospects in the biological control of I. aegyptiaca.

Multi‐omics reveal the molecular basis of LrAN2 overexpression in black goji callus promoting the excessive accumulation of petanin, a promising food blue colorant

AbstractLycium ruthenicum fruit (LRF) is a potential source of natural colorant in a wide pH range due to richness in monoacylated anthocyanin petanin. However, the yield of LRF largely lags behind the market demand in food industry. In this study, overexpressing LrAN2 (LrAN2OE), an anthocyanin activator in LRF, produced excessive acylated anthocyanins including petanin in L. ruthenicum callus (LRC). Physiological analysis indicates that LrAN2OE extensively orchestrate the redox homeostasis, including antioxidant enzymes system and antioxidants with low molecular weight. KEGG enrichment analysis indicates that LrAN2 hierarchically orchestrate the acylated anthocyanin biosynthesis in LRC at multi‐omics level, such as small RNAome, transcriptome, and metabolome. The anthocyanin yield of LrAN2OE callus cultured by 5% sucrose or glucose is significantly enhanced. Furthermore, the anthocyanin yield approach to 96.23 mg/g dry weight, approximately 3.5 folds of that in LRF, when LrAN2OE suspension cells are cultured in liquid MS medium supplement with 5% sucrose and 100 mM NaCl. Notably, anthocyanins extracted from LrAN2OE callus are stable in pH 1.0–2.0, pH 7.0, and pH 9.0, showing red or blue color within 30 days at 4°C. Our findings suggest that LrAN2 is perfect gene resource for metabolic engineering of acylated anthocyanins in LRC, a promising chassis producing acylated anthocyanins. Taken together, LRC metabolically engineered by LrAN2 is a potential source of natural food color, which facilitates to make up the shortfall of LRF as source of natural colorant in future food industry.

Behavior of magnetic systems of different dimensions in a magnetic field

Purpose. To investigate the influence of the magnetic field on the formation of structures in magnetic media of various dispersities. Methods. Experiments to study the dynamics of magnetic inclusions were carried out on a self-made installation in flat transparent cells by microscopy. The magnetic field was created by an electromagnet FL-1 connected to a power source. Magnetite particles of various sizes, as well as metal balls with a diameter of 0.5 mm, were studied as a magnetic medium. Video recording was performed using a MICMED WiFi 2000X 5.0 microscope. Results. The dynamics of magnetic inclusions in a viscous liquid medium under the influence of a magnetic field, as well as under conditions of mechanical shear effects, have been studied. The influence of the magnetic field strength on the growth rate of chain structures, as well as on the angle of deflection under shear action, has been studied. A theoretical interpretation of the observed phenomena is proposed. Conclusion. During the experiment, it was found that under the influence of a magnetic field, magnetic inclusions form chain structures. Their size, growth rate and dynamics depend on the physical parameters of the system and the external magnetic field. An intensive increase in the formation of chains of magnetic inclusions was detected at low and medium values of the magnetic field strength. An experimental dependence of the angle of deviation of chain structures from the equilibrium position on the magnetic field strength is obtained, which correlates with known theoretical data, on the basis of which a computational model is proposed. The results of the study can be used to visualize numerical calculations of the dynamics of dispersed systems under external influences.

Optimization, gene cloning, expression, and molecular docking insights for enhanced cellulase enzyme production by Bacillus amyloliquefaciens strain elh1

BackgroundIn this study, we isolated a cellulase-producing bacterium, Bacillus amyloliquefaciens strain elh, from rice peel. We employed two optimization methods to enhance the yield of cellulase. Firstly, we utilized a one-variable-at-a-time (OVAT) approach to evaluate the impact of individual physical and chemical parameters. Subsequently, we employed response surface methodology (RSM) to investigate the interactions among these factors. We heterologously expressed the cellulase encoding gene using a cloning vectorin E. coli DH5α. Moreover, we conducted in silico molecular docking analysis to analyze the interaction between cellulase and carboxymethyl cellulose as a substrate.ResultsThe bacterial isolate eh1 exhibited an initial cellulase activity of 0.141 ± 0.077 U/ml when cultured in a specific medium, namely Basic Liquid Media (BLM), with rice peel as a substrate. This strain was identified as Bacillus amyloliquefaciens strain elh1 through 16S rRNA sequencing, assigned the accession number OR920278 in GenBank. The optimal incubation time was found to be 72 h of fermentation. Urea was identified as the most suitable nitrogen source, and dextrose as the optimal sugar, resulting in a production increase to 5.04 ± 0.120 U/ml. The peak activity of cellulase reached 14.04 ± 0.42 U/ml utilizing statistical optimization using Response Surface Methodology (RSM). This process comprised an initial screening utilizing the Plackett–Burman design and further refinement employing the BOX -Behnken Design. The gene responsible for cellulase production, egl, was effectively cloned and expressed in E. coli DH5α. The transformed cells exhibited a cellulase activity of 22.3 ± 0.24 U/ml. The egl gene sequence was deposited in GenBank with the accession number PP194445. In silico molecular docking revealed that the two hydroxyl groups of carboxymethyl cellulose bind to the residues of Glu169 inside the binding pocket of the CMCase. This interaction forms two hydrogen bonds, with an affinity score of −5.71.ConclusionsOptimization of cultural conditions significantly enhances the yield of cellulase enzyme when compared to unoptimized culturing conditions. Additionally, heterologous expression of egl gene showed that the recombinant form of the cellulase is active and that a valid expression system can contribute to a better yield of the enzyme.

Structural-Mechanical Modification of Amorphous Polyethylene Terephthalate and Hybrid Nanocomposite Materials Based on It

Hybrid nanocomposite materials based on polyethylene terephthalate and inorganic flame-retardant diammonium phosphate were prepared according to the fundamental strategy of environmental crazing of polymers. Structural-mechanical modification of the initial amorphous polyethylene terephthalate and the resultant nanocomposite polyethylene terephthalate-based was carried out by rolling at room temperature. The effect of preliminary rolling on the deformation behavior of polyethylene terephthalate during subsequent stretching in air and in physically active liquid media was established.