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The purpose of this investigation was to explore the fabrication of a self-assembled complex of potato starch (PS) and pomegranate peel polyphenols (PP) by ball milling and to investigate its digestion characteristics. The impact of ball milling time, ball milling speed, and PS/PP mass ratio on the total polyphenol content and digestion characteristics of the self-assembled complex was investigated. Then, the formed product was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). The results showed that the content of total polyphenols was (19.91 ± 0.32) mg/g in the product obtained under the following conditions: milling time 10 h, rotational speed 500 r/min, and mass ratio of PS to PP 1:0.15. The SEM results showed that many cracks and gullies appeared on the surface of the product, which was accompanied by an agglomeration phenomenon. The XRD results showed that the crystalline domain of starch was destroyed by ball milling, and the intensity of the diffraction peak became weakened or even disappeared, indicating that the granules were changed into an amorphous structure. The FTIR results showed that the absorption peak at 3 600–3 400 cm-1 was enhanced, which illustrated that PP and PS were self-assembled through hydrogen bonds. Hence, ball milling can be used to fabricate PS/PP self-assembled complex. The TGA results demonstrated that the thermal stability of the self-assembled complex was improved. Furthermore, in vitro simulated digestion and in vitro simulated gastrointestinal release tests showed that the proportion of resistant starch in the complex was significantly increased, which was beneficial to maintain the stability of the guest molecules during the digestion process, and allowed the targeted release of polyphenols in the large intestine and colon, enabling the guest molecules to exert their functions better, thereby improving their bioavailability.

Background: Hair loss is a widespread health problem that affects numerous individuals and is associated with age, lack of sleep, stress, endocrine problems, and other problems. Caffeine exerts various pharmacological effects, particularly after ingestion. The caffeine‐induced inhibition of phosphodiesterases can increase intracellular cAMP concentrations, ultimately resulting in stimulatory effects on cell metabolism and proliferation. Hence, caffeine has been confirmed to inhibit hair loss caused by premature termination of the hair growth phase. Adenosine also improves hair loss by stimulating hair growth and thickening hair shafts. However, further empirical evidence is required to comprehensively assess the efficacy of hair loss treatment and prevention using a formulation of caffeine and adenosine in specific proportions in shampoos. Objectives: This study aimed to evaluate a shampoo with caffeine and adenosine as a daily scalp care product for hair loss in 77 subjects aged 18–60 years. Methods: The overall and local hair densities were assessed using professional cameras and dermoscopes at different magnifications and distances. Five hairs that came off the participant's head were randomly selected to measure hair diameter. The self‐assessment questionnaires were filled on third month of product use. Results: The combination of caffeine and adenosine in the shampoo significantly enhanced hair density compared to that of the baseline. The results revealed a significant reduction in hair loss. The hair diameters of the subjects did not change significantly. Most of the participants (71.05%) were satisfied with their hair after using the product. Conclusions: Shampoos containing caffeine and adenosine have been demonstrated to exert therapeutic benefits for reducing hair loss. [ABSTRACT FROM AUTHOR]

Background: The human skin microbiome and lipidome are essential for skin homeostasis and barrier function, and have become a focus in both dermatological and cosmetic fields. However, the influence of surfactants commonly used in cosmetic products on the skin resident microbiome and lipidome remains poorly characterized. Methods: We conducted self‐control experiments to systematically study the effects of surfactant (sodium lauroyl sarcosinate [SLS]) on facial skin. Wrinkles, pores, porphyrins, and superficial lipids were examined to evaluate the biophysical state of skin. Quantitative real‐time PCR was used to detect the numbers of bacteria and fungi. The diversity and structure of prokaryotic and eukaryotic microbiomes were assessed using 16S rDNA and ITS amplicon sequencing, respectively. Moreover, 22 lipids were identified to evaluate lipidome variations. SPSS software was used for statistical analysis. Results: SLS in facial cleanser did not extensively influence skin biophysical parameters, but caused a decrease in porphyrin. After using the SLS‐added facial cleanser for 3 weeks, the alpha diversity of the prokaryotic microbial community decreased significantly, while the eukaryotic microbial community showed a continuous downward trend but no statistically significant. A shift in the structure of prokaryotic microbiome was observed as a result of SLS exposure, mainly reflected by the increase in Acinetobacter, Escherichia‐Shigella, Streptococcus, and Ralstonia, while the SLS had little effect on the structure of the eukaryotic microbiome. Furthermore, SLS exposure had a great impact on skin lipidome, mainly manifested by the increase of phosphatidylglycerol (PG) and phosphatidylcholine (PC), and the decrease of ceramides. Spearman's correlations analysis showed that Escherichia‐Shigella, Pseudomonas, and Acinetobacter are positively correlated with PG and PC; however, the correlation is not statistically significant. Conclusion: In this study, we found the SLS in facial cleanser primarily affected lipidome and the prokaryotic microbiome of facial skin. These findings are useful for reminding us to be vigilant about the ingredients in personal care products, even the common ingredients, and designing effective formulations for repairing ecological balance of skin. [ABSTRACT FROM AUTHOR]

Background: Skin aging is a complex multifactorial progressive process. With age, intrinsic and extrinsic factors cause the loss of skin elasticity, with the formation of wrinkles, resulting in skin sagging through various pathways. A combination of multiple bioactive peptides could be used as a treatment for skin wrinkles and sagging. Objectives: This study aimed to evaluate the cosmetic efficacy of a multi‐peptide eye serum as a daily skin‐care product for improving the periocular skin of women within the ages of 20–45 years. Methods: The stratum corneum skin hydration and skin elasticity were assessed using a Corneometer CM825 and Skin Elastometer MPA580, respectively. The PRIMOS CR technique based on digital strip projection technology was used for skin image and wrinkle analysis around the "crow's feet" area. Self‐assessment questionnaires were filled on Day 14 and 28 of product use. Results: This study included 32 subjects with an average age of 28.5 years. On Day 28, there was a significant decrease in the number, depth, and volume of wrinkles. Skin hydration, elasticity, and firmness increased continuously during the study period, consistent with typical anti‐aging claims. A majority of the participants (75.00%) expressed overall satisfaction with their skin appearance after using the product. Most participants noted a visible skin improvement, with an increase in skin elasticity and smoothness, and confirmed the extensibility, applicability, and temperance of the product. No adverse reactions related to product use were observed. Conclusions: The multi‐peptide eye serum uses a multi‐targeted mechanism against skin aging to improve the skin appearance, making it an ideal choice for daily skincare. [ABSTRACT FROM AUTHOR]

Streptomyces ansochromogenes SanG is a pathway-specific regulator that mainly controls the transcription of two transcriptional units involved in nikkomycin biosynthesis. SanG consists of three major functional domains: an N-terminal Streptomyces antibiotic regulatory protein (SARP) domain, a central ATPase domain, and a C-terminal half homologous to guanylate cyclases belonging to the LuxR family. SanG was expressed in Escherichia coil as a C-terminally [His.sub.6]tagged protein. The purified SanG-[His.sub.6] was shown to be a dimer in solution by dynamic light scattering. An electrophoretic mobility-shift assay showed that the purified SanG protein could bind to the DNA fragment containing the bidirectional sanN--sanQ promoter region. The SanG-binding sites within the bidirectional sanN--sanQ promoter region were determined by footprinting analysis and identified a consensus-directed repeat sequence 5'-CGGCAAG-3'. SanG showed significant ATPase/GTPase activity in vitro, and addition of ATP/GTP enhanced the affinity of SanG for target DNA, but ATP/GTP hydrolysis was not essential for SanG binding to the target DNA. However, real-time reverse transcription PCR showed that mutation of the ATPase/GTPase domain of Sang significantly decreased the transcriptional level of sanN--I and sanO--V. These results indicated that the ATPase/GTPase activity of SanG modulated the transcriptional activation of SanG target genes during nikkomycin biosynthesis. DOI 10.1099/mic.0.033605-0

A homologous gene (iunH) of a putative nucleoside hydrolase (NH), which had been identified from the exosporia of Bacillus cereus and Bacillus anthracis spores, was cloned from Bacillus thuringiensis subsp, kurstaki. Disruption of iunH did not affect the vegetative growth and sporulation of Bacillus thuringiensis, but promoted both inosine- and adenosine-induced spore germination. The inosine- or adenosine-induced germination rate decreased when the wild-type iunH gene was overexpressed in Bacillus thuringiensis. The iunH gene product was characterized as a purine-specific NH. The kinetic parameters of lunH with inosine as substrate were [K.sub.m]=399 [+ or -] 115 [micro]M, [k.sub.cat] = 48.9 [+ or -] 8.5 [s.sup.-1] and [k.sub.cat]/[K.sub.m]=1.23x[10.sup.5] [M.sup.-1] [s.sup.-1]. The optimal pH and temperature for lunH were found to be pH 6 and 80 [degrees]C. Meanwhile, the specific activity of inosine hydrolase in intact spores of the wild-type strain with inosine as substrate was 2.89 [+ or -] 0.23 x [10.sup.-2] [micro]mol [min.sup.-1] [(mg dry wt).sup.-1]. These results indicate that lunH is important in moderating inosine- or adenosine-induced germination of Bacillus thuringiensis spores.

Abstract Background sabR is a pleiotropic regulatory gene which has been shown to positively regulate the nikkomycin biosynthesis and negatively affect the sporulation of Streptomyces ansochromogenes. In this study, we investigate the mechanism of SabR on modulating nikkomycin production in Streptomyces ansochromogenes. Results The transcription start point of sabR was determined by high-resolution S1 nuclease mapping and localized at the nucleotide T at position 37 bp upstream of the potential sabR translation start codon (GTG). Disruption of sabR enhanced its own transcription, but retarded the nikkomycin production. Over-expression of sabR enhanced nikkomycin biosynthesis in Streptomyces ansochromogenes. EMSA analysis showed that SabR bound to the upstream region of sanG, but it did not bind to the upstream region of its encoding gene (sabR), sanF and the intergenic region between sanN and sanO. DNase 1 footprinting assays showed that the SabR-binding site upstream of sanG was 5'-CTTTAAGTCACCTGGCTCATTCGCGTTCGCCCAGCT-3' which was designated as SARE. Deletion of SARE resulted in the delay of nikkomycin production that was similar to that of sabR disruption mutant. Conclusions These results indicated that SabR modulated nikkomycin biosynthesis as an enhancer via interaction with the promoter region of sanG, and expanded our understanding about regulatory cascade in nikkomycin biosynthesis.

The purpose of this study was to estimate the antibacterial properties of aqueous suspensions of dialdehyde microcrystalline cellulose (DAMC), and a model of the observed antibacterial kinetics was proposed and validated. The DAMC was prepared from microcrystalline cellulose by periodate oxidation. The bacterial inactivation kinetics of aqueous suspensions of DAMC was investigated by measuring the bactericidal effect after different contact times. The results indicated that with a DAMC aldehyde content of 6.34 mmol/g, the MICs for S . aureus , E . coli , B . subtilis and S . typhimurium were 15, 15, 15 and 30 mg/mL, respectively. This research thus establishes an antibacterial kinetics model of DAMC with 6.34 mmol/g of aldehyde content. At 37 °C and atmospheric pressure, the bacterial inactivation kinetic conformed to the equation: Log reduction of bacteria = − k [DAMC] t. [ABSTRACT FROM AUTHOR]

Natamycin, an important 26-member tetraene macrolide antifungal antibiotic, is widely used as antifungal agent in the food industry and medical fields. However, low yields of the currently used production strains limit its wider applications. To improve the productivity of natamycin-producing strains, we co-expressed the Vitreoscilla hemoglobin gene vgb in Streptomyces gilvosporeus with two genes that constitute part of the natamycin biosynthesis gene cluster: pimE (encoding a signalling protein) and pimM (encoding a positive regulator). Both genes were cloned and ligated into the shuttle vector pIMEP under the control of the strong, constitutive Perm promoter, and integrated into the chromosome of S. gilvosporeus via conjugation. Natamycin production was increased 40.3% upon overexpression of pimE and pimM. Furthermore, in order to alleviate oxygen limitation, we additionally expressed vgb in the pimE and pimM over-expressing strain, yielding S. gilvosporeus/pIMEP::pimE::pimM::vgb, which showed a further 55.7% improvement for natamycin production compared to that of the recipient strain. In conclusion, co-expression of pimE and pimM with vgb led to markedly increased natamycin production, thus pointing out a potential strategy for enhancing the microbial production of other antibiotics as well. [ABSTRACT FROM AUTHOR]

In the last decades, the separation of actinides was widely and continuously studied in China. A few kinds of salt-free reductants to adjust Pu and Np valences have been investigated. N, N-dimethylhydroxylamine is a good reductant with high reduction rate constants for the co-reduction of Pu(IV) and Np(VI), and monomethylhydrazine is a simple compound for the individual reduction of Np(VI). Advanced PUREX based on Organic Reductants (APOR) was proposed. Trialkylphosphine oxide (TRPO) with a single functional group was found to possess strong affinity to tri-, tetra- and hexa-valent actinides. TRPO process has been first explored in China for actinides partitioning from high level waste and the good partitioning performance was demonstrated by the hot test. High extraction selectivity for trivalent actinides over lanthanides by dialkyldithiophosphinic acids was originally found in China. A separation process based on purified Cyanex 301 for the separation of Am from lanthanides was presented and successfully tested in a battery of miniature centrifugal contactors. [ABSTRACT FROM AUTHOR]

In this study, a trioctylmethylammonium chloride (N263)- tributyl phosphate (TBP)- n -octanol-sulfonated kerosene (N263-T) synergistic extraction system and an N263- n -octanol-sulfonated kerosene (N263–O) system were used to treat cyanide (CN)-bearing wastewater. The extraction saturation capacity of the two systems was measured. The influences of the initial pH and phase ratio (O/A) of the two systems on extraction were compared and analyzed. Fourier transform infrared (FTIR) spectroscopy, ultraviolet–visible (UV–Vis) spectroscopy, and slope methods were used to analyze the characteristic functional groups in the loaded organic phase, the compositions of the extracted compounds in the extraction reactions and the reaction mechanism. The results indicated that the saturated extraction capacity of the N263-T system, which was much larger than that of the N263–O system, for metal CN complex ions was 4354.31 mg/L. In addition, the N263-T system operated over a wider pH range. The extraction rates of copper (Cu), zinc (Zn), and iron (Fe) ions at pH 14 were 97.4%, 99.1%, and 87.2%, respectively. There was a strong compatibilization effect of TBP on the extraction system. The extraction efficiency of the N263-T system for metal CN complex ions was higher than that of the N263–O system when O/A = 0.4. The saturated loaded N263-T and N263–O systems were stripped by 1 mol/L NaOH +2 mol/L NaSCN solution at O/A = 3. The metal ion concentration in the stripping solution could be enriched to 11996.6 and 8913.3 mg/L for the N263-T and N263–O systems, respectively. During the extraction process, the binding ratios of N263 cations to Cu(CN) 3 2−, Zn(CN) 4 2−, and Fe(CN) 6 3− were 2:1, 2:1, and 3:1, respectively. The binding ratios of TBP to Cu(CN) 3 2−, Zn(CN) 4 2−, and Fe(CN) 6 3− in wastewater were 3:1, 4:1, and 6:1, respectively. The P O group in TBP was linked to the C N group of the metal CN complex ion by hydrogen bonds using the water molecule as a bridge to form a supramolecular anion group, which entered into the organic phase and combined with the N263 cation under the action of ion association. [Display omitted] • An approach for valuable metals recovery from cyanide wastewater is developed. • The N263-T was more effective at O/A of 0.4, N263 and TBP concentration of 10 vol%. • TBP is attached to the C N group of the metal complex ion by hydrogen bonding. • The binding ratios of TBP to Cu, Zn and Fe are 3:1, 3:1 and 6:1. • N263 binds to anionic groups in ratios of 2:1(Cu), 2:1(Zn), 3:1(Fe). [ABSTRACT FROM AUTHOR]

Abstract Native potato starch (NPS) with tea polyphenols (TPs) was treated in a planetary ball mill, and the effects of co-grinding on properties and digestibility of starch were studied. The X-ray diffraction (XRD) results showed that the crystal structure of starch granules was destroyed after 7 h of ball grinding, and their crystallinity degree reduced from 38.1% to 8.3%. The scanning electron microscopy (SEM) analyses indicated that the damaged starch granules and TPs displayed agglomerates after 7 h of milling. The Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) results demonstrated the existence of an interaction between starch chains and TPs, which improved the thermal stability and gelatinization temperatures of starch. The ball-milled starches with different amount of TPs showed significant variability to in vitro digestion (the contents of slowly digestible starch and resistant starch). Therefore, the produced ball-milled mixtures may be a desired dietary product for postprandial glycemic control. Highlights • Potato starch (PS) with tea polyphenols (TPs) was ball milled. • Morphology of PS granules was seriously affected due to the TPs. • An interaction between PS and TPs was formed. • The content of TPs could influence the digestion of starch. [ABSTRACT FROM AUTHOR]

Dialdehyde cellulose (DAC) was produced by the selective oxidation of pulp fibers, and was used to bind bovine serum albumin (BSA) by forming Schiff bases. The best binding conditions were as follows: a content of DAC aldehyde groups of 5.15 ± 0.13 mmol/g, a reaction time of 4 h, a reaction temperature of 40 °C, an initial medium pH of 8.0, and a DAC/BSA ratio of 1:50 (g/mL). After the binding of BSA, the FT-IR intensity of the characteristic absorption band (C O) of DAC was weakened, which indicated the formation of imine linkages. The Schiff bases formed between DAC and BSA gave the resulting material a higher thermal stability than that of DAC, and the slender fibers were twisted out of shape. Based on this Schiff base reaction, three different crude polysaccharide solutions (CPSs) were treated with DAC to deproteinize them under best bonding conditions. The results revealed that the DAC method had a higher deproteinization efficiency and polysaccharide recovery than the classical Sevag method. Therefore, the DAC treatment may be an ideal technique for the removal of proteins from CPSs for large-scale purification of polysaccharides. [ABSTRACT FROM AUTHOR]

• A novel Schiff base was derived from dialdehyde cellulose (DAC) and l -lysine (Lys). • The formation of Schiff base between DAC and Lys was confirmed. • The DAC-Lys Schiff base exhibited higher antibacterial activity than DAC. • The DAC-Lys Schiff base may be a promising antibacterial agents. A cellulose-based Schiff base was synthetized via condensation reactions of dialdehyde cellulose (DAC) with l -lysine (Lys) and its antimicrobial activity was evaluated. The results of amino acid analysis, viscosity measurement, FTIR spectra, X-ray diffraction patterns, and solid-state cross-polarization (CP)/magic angle spinning (MAS) 13C-NMR indicated that the cellulose-based Schiff base (DAC-Lys) between DAC and Lys were formed. Thermogravimetric analysis (TGA) results showed that as compared with DAC, the DAC-Lys had diminished thermostability. When l -lysine content in DAC-Lys was 9.93 ± 0.35 g/100 g sample, the DAC-Lys exhibited high antibacterial activity against Staphylococcus aureus , Bacillus subtilis , Escherichia coli and Salmonella typhimurium , and their MIC values were 7.5, 3.75, 7.5 and 3.75 mg/mL, respectively. The cellulose-based Schiff base, with good antibacterial activity, non-toxicity, and permissible biocompatibility, might be potential additives in papermaking for the introduction of antibacterial agents. [ABSTRACT FROM AUTHOR]

Bis(2,4,4-trimethylpentyl)dithiophosphinic acid, commonly referred to as HBTMPDTP or Cyanex301, is a sulfur-donating ligand that shows considerable promise in the challenging task of separating trivalent actinides (An 3+ ) from lanthanides (Ln 3+ ). Although its effectiveness has been established, the specific molecular details about the preference of HBTMPDTP for americium over europium have remained a mystery, puzzling researchers for over two decades. This study presents a comprehensive, dual-driven separation mechanism for this complex system combining experimental and theoretical approaches. A critical finding is the increased covalency in An-S bonds compared to Ln-S bonds, which plays a significant role in HBTMPDTP's intrinsic selectivity for An 3+ over Ln 3+ . This leads to the formation of distinct An 3+ and Ln 3+ species, enhancing the ligand's actinide selectivity. Additionally, it provides crucial insights into the coordination chemistry of f-elements with sulfur-donating ligands, thereby deepening our understanding of this intricate field.

Streptomyces are the soil-dwelling bacteria with a complex lifecycle and a considerable ability to produce a variety of secondary metabolites. Osmoregulation is important for their lifecycle in nature. In the genome of Streptomyces coelicolor M145, SCO3128 (encodes a putative fatty acid desaturase), SCO3129 (encodes a putative TetR family regulator) and SCO3130 (encodes a putative l-carnitine dehydratase) constitute a transcriptional unit, and its transcript was found to be in response to osmotic stress. Disruption of SCO3130 led to a bald phenotype on MMG medium and the mycelia lysis on the edge of the colony when KCl/NaCl was added to the medium. These results indicated that SCO3130 is important for the osmotic stress resistance in S. coelicolor . Transcriptional analysis and electrophoretic mobility shift assays (EMSA) demonstrated that SCO3129 repressed the transcription of SCO3128-3130 operon through directly binding to the promoter region of SCO3128 , indicating that SCO3129 regulates the transcription of SCO3128-3130 in response to osmotic stress.

The extracted complexes of trivalent lanthanides (Ln(III)) with purified Cyanex 301 (bis(2,4,4-trimethylpentyl)dithiophosphinic acid, denoted as HA) were investigated by extended X-ray absorption fine structure spectroscopy (EXAFS), UV-Vis and fluorescence spectroscopy. In the complexes prepared under the same conditions of solvent extraction, the light Ln(III) ions are mainly coordinated by the sulfur atoms of the ligands, and the middle Ln(III) ions are coordinated by mixed donors, the sulfur atoms of the ligands and the oxygen atoms of the extracted water, while the heavy Ln(III) ions are completely hydrated in the organic phase without any sulfur atoms of the ligands in the coordination shell. As the atomic number increases, the extracted water molecules gradually replace the sulfur atoms of the ligands in the first coordination shell of Ln(III), and simultaneously the ligand anions become counterions just for balancing the positive charge of the fully hydrated heavy Ln(III) ions. The effect of the change in the complex structures on the extraction of Ln(III) ions with HA was evaluated by the co-extraction of other thirteen individual Ln(III) together with Nd(III). In contrast to most ligands bonding more strongly to heavier Ln(III), HA preferentially extracts lighter Ln(III), suggesting that the unusual extraction capability of HA for Ln(III) might originate from the difference in the complex structures with Ln(III) ions.

Efficient capture of highly toxic radionuclides with long half-lives such as Americium-241 is crucial to prevent radionuclides from diffusing into the biosphere. To reach this purpose, three different types of mesoporous silicas functionalized with phosphonic acid ligands (SBA-POH, MCM-POH, and BPMO-POH) were synthesized via a facile procedure. The structure, surface chemistry, and micromorphology of the materials were fully characterized by (31)P/(13)C/(29)Si MAS NMR, XPS, and XRD analysis. Efficient adsorption of Am(III) was realized with a fast rate to reach equilibrium (within 10 min). Influences including structural parameters and functionalization degree on the adsorption behavior were investigated. Slope analysis of the equilibrium data suggested that the coordination with Am(III) involved the exchange of three protons. Moreover, extended X-ray absorption fine structure (EXAFS) analysis, in combination with XPS survey, was employed for an in-depth probe into the binding mechanism by using Eu(III) as a simulant due to its similar coordination behavior and benign property. The results showed three phosphonic acid ligands were coordinated to Eu(III) in bidentate fashion, and Eu(P(O)O)3(H2O) species were formed with the Eu-O coordination number of 7. These phosphonic acid-functionalized mesoporous silicas should be promising for the treatment of Am-containing radioactive liquid waste.