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Plant roots significantly influence soil microbial diversity, and soil microorganisms play significant roles in both natural and agricultural ecosystems. Although the genetically modified (GM) crops with enhanced insect and herbicide resistance are thought to have unmatched yield and stress resistance advantages, thorough and in‐depth case studies still need to be carried out in a real‐world setting due to the potential effects of GM plants on soil microbial communities. In this study, three treatments were used: a recipient soybean variety Jack, a triple transgenic soybean line JD321, and the glyphosate‐treated JD321 (JD321G). Three sampling stages (flowering, seed filling and maturing), as well as three host niches of soybean rhizosphere [intact roots (RT), rhizospheric soil (RS) and surrounding soil (SS)] were established. In comparison to Jack, the rhizospheric soil of JD321G had higher urease activity and lower nitrite reductase at the flowering stage. Different treatments and different sampling stages existed no significant effects on the compositions of microbial communities at different taxonomic levels. However, at the genus level, the relative abundance of three plant growth‐promoting fungal genera (i.e. Mortierella, Chaetomium and Pseudombrophila) increased while endophytic bacteria Chryseobacterium and pathogenic bacteria Streptomyces decreased from the inside to the outside of the roots (i.e. RT → RS → SS). Moreover, two bacterial genera, Bradyrhizobium and Ensifer were more abundant in RT than in RS and SS, as well as three species, Agrobacterium radiobacter, Ensifer fredii and Ensifer meliloti, which are closely related to nitrogen‐fixation. Furthermore, five clusters of orthologous groups (COGs) associated to nitrogen‐fixation genes were higher in RT than in RS, whereas only one COG annotated as dinitrogenase iron‐molybdenum cofactor biosynthesis protein was lower. Overall, the results imply that the rhizosphere host niches throughout the soil–plant continuum largely control the composition and function of the root‐associated microbiome of triple transgenic soybean. [ABSTRACT FROM AUTHOR]

Aims: This study was conducted to evaluate 35 natural flavonoids for their in vitro susceptibility against E. coli (ATCC 25922), Ps. aeruginosa (ATCC 27853), B. subtilis (ATCC 530) and Staph. aureus (ATCC 6538) in search of a potential broad‐spectrum antibiotic. Methods and Results: Glabridin, a natural isoflavonoid isolated from Glycyrrhiza glabra L., was identified to be highly active with a MIC of 8–16 μg ml−1 against Staph. aureus, B. subtilis and E. coli. By the results of the docking simulation, we located the potential targets of glabridin as DNA gyrase and dihydrofolate reductase (DHFR). The subsequent DNA gyrase inhibition assays (glabridin: IC50 = 0.8516 μmol L−1, ciprofloxacin: IC50 = 0.04697 μmol L−1), DHFR inhibition assays (glabridin: inhibition ratio = 29%, methotrexate: inhibition ratio = 45% under 100 μmol L−1 treatment) and TUNEL confirmed that glabridin acted as DNA gyrase inhibitor and DHFR mild inhibitor, exerting bactericidal activity by blocking bacterial nucleic acid synthesis. CCK‐8 and in silico calculations were also conducted to verify the low cytotoxicity and acceptable druggability of glabridin. Conclusion: These findings suggest that glabridin represents the prototypical member of an exciting structural class of natural antimicrobial agents. Significance and Impact of the Study: This study reports a novel mechanism of bactericidal activity of glabridin against Staph. aureus. [ABSTRACT FROM AUTHOR]

Nitrogen-doped TiO2 and reduced graphene oxide (RGO) nanocomposites (NTG) were prepared by sol-gel method followed by annealing treatment process under N2 atmosphere. The as-prepared NTG nanocomposite were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet-visible diffuse reflectance spectroscopy (DRS). The results indicate that the incorporation of nitrogen onto both RGO and TiO2 was accomplished simultaneously in the facile process. Nitrogen doping makes the light excitation range red shift and can enhance the electron-hole separation effectively. The photocatalytic activity of the as-prepared samples was evaluated through the degradation of methyl orange (MO) under visible light irradiation. The introduction of nitrogen increased the photodegradation activity, which can be indicated by the fitted apparent first-order kinetics rate constant k, increasing about four times from 0-NTG-450 to 15-NTG-450. The annealing treatment further increased the photodegradation activity about 1.5 times of 15NTG-450 for 15NTG-800. [ABSTRACT FROM AUTHOR]

Enzyme-catalysis self-assembled oligopeptide hydrogel holds great interest in drug delivery, which has merits of biocompatibility, biodegradability and mild gelation conditions. However, its application for protein delivery is greatly limited by inevitable degradation of enzyme on the encapsulated proteins leading to loss of protein activity. Moreover, for the intracellularly acted proteins, cell membrane as a primary barrier hinders the transmembrane delivery of proteins. The internalized proteins also suffer from acidic and enzymatic degradation in endosomes and lysosomes. We herein develop a protease-manipulated hybrid nanogel/nanofiber hydrogel for localized delivery of intracellularly acted proteins. The embedded polymeric nanogels (CytoC/aNGs) preserve activity of cytochrome c (CytoC) that is an intracellular activator for cell apoptosis as a model protein against proteolysis, and do not affect the gelation properties of the protease-catalysis assembled hydrogels. The injectable hydrogel (CytoC/aNGs/Gel) serves as a reservoir to enhance intratumoral retention and realize sustainable release of CytoC/aNGs. The released CytoC/aNGs increase cellular uptake of CytoC and enhance its intracellular delivery to its target site, cytoplasm, resulting in favorable apoptosis-inducing and cytotoxic effects. We show that a single local administration of CytoC/aNGs/Gel efficiently inhibit the tumor growth in the breast tumor mouse model. A protease-manipulated hybrid nanogel/nanofiber hydrogel (CytoC/aNGs/Gel) was developed for localized delivery of an intracellularly-acted protein, cytochrome c (CytoC). A single local administration of CytoC/aNGs/Gel efficiently inhibited the tumor growth in breast tumor mouse model. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study was aimed at formulating and evaluating a novel solid self‐emulsifying delivery system (S‐SEDS) for the application in functional foods of dihydromyricetin (DMY). First, solubility study and pseudo‐ternary phase diagram analysis were adopted to optimize the formulation of liquid self‐emulsifying delivery system (L‐SEDS). And the thermodynamic stable L‐SEDS with 5% content of DMY was fabricated and further developed into a solid form via vacuum rotary evaporation with Aerosil 300 as the solid adsorbent. Solid state characterization of the S‐SEDS was performed by scanning electron microscopy, Fourier‐transform infrared spectroscopy, and X‐ray powder diffraction. Furthermore, studies proved that the antioxidant activity and bioaccessibility of DMY were improved after incorporated into S‐SEDS formulation compared to pure DMY. The S‐SEDS showed good resistance against various storage conditions investigated for 10 weeks. Practical Application: Solid self‐emulsifying delivery system (S‐SEDS) combined the advantages of liquid self‐emulsifying delivery system with those of a solid dosage form to overcome the disadvantages associated with liquid formulations is more convenient for storage and transportation in practical application. Furthermore, the technology of producing S‐SEDS is simple and can be realized in industrial production. Hence, S‐SEDS could be a promising strategy to overcome the poor water solubility and short biological half‐life of dihydromyricetin for further application in functional foods and beverage industry. [ABSTRACT FROM AUTHOR]

In the present study, a solid self‐emulsification delivery system (S‐SEDS) is developed to improve the bioavailability of astaxanthin (ASX). The pseudo ternary phase diagram method is used to screen the optimum composition of liquid self‐emulsification delivery system (SEDS). This liquid system is converted into solid state using the solid absorbent carrier by simple physical mixing. Through the analysis of powder flowability and adsorption capacity, silicon dioxide and anhydrous calcium hydrogen phosphate are selected as solid carriers of the liquid self‐emulsification system. Results of Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) indicate that astaxanthin is encapsulated in these solid carriers. In the in vitro dissolution study, sustained release of astaxanthin from two different ASX‐SEDS (prepared with silicon dioxide and anhydrous calcium hydrogen phosphate) is obtained and the cumulative release is correspondingly 51.06 ± 0.98 and 49.97 ± 0.87% within 2 h. A delayed pattern of absorbed ASX‐SEDS is observed in the study with anhydrous calcium hydrogen phosphate compared to the counterpart with silicon dioxide, which is consistent with the result from the in vitro digestion study. Antioxidant study shows that astaxanthin can be encapsulated in S‐SEDS without the loss of antioxidant activity. Consequently, S‐SEDS can be a promising vehicle in food industry. Practical Applications: Traditionally, liquid‐based delivery systems are prepared using liquid components, which have some disadvantages, such as, complex production process, low active ingredient loading, narrow application range, and lacking of effective evaluation methods. The present study adopts physical adsorption, a gentle and simple process, to prepare the solid self‐emulsifying system. This system combines the advantages of liquid‐based systems and solid dosage forms, which can improve the solubility of poorly solubility active ingredient in intestinal environments, and the high solubility of active ingredient is favor to its absorption. In the present work, the active ingredients solubilization capability of solid formulations is evaluated by in vitro dissolution and digestion studies. It can be seen that over 40% of astaxanthin are released from solid self‐emulsifying systems in 120 min. After the process of digestion, the bioaccessibility reaches 10%. The results of in vitro dissolution and digestion show that after solid adsorption, astaxanthin exhibits delayed release patterns. All the studies demonstrate that solid self‐emulsifying system is an appropriate strategy to improve the bioavailability of astaxanthin. The pseudo ternary phase diagram method is used to screen the optimum composition of liquid self‐emulsification delivery system. Then, this liquid system is converted into solid state using the solid absorbent carrier by simple physical mixing. [ABSTRACT FROM AUTHOR]

Ginsenoside Rh2 (3 β - O -Glc-protopanaxadiol), a trace but an important pharmacological component of ginseng, has exhibited excellent medicinal potential. Many studies have found that the synthesis of Rh2 by UDP-glucosyltransferase (UGT) is an alternative production strategy. In this study, Yjic from B. subtilis 168 was found to synthesize ginsenoside F12 (3 β ,12 β -Di- O -Glc-protopanaxadiol) and Rh2 at a ratio of 7:3. Yjic regioselectivity toward Rh2 synthesis was successfully improved using a semi-rational design including structure-guided alanine scanning and saturation mutations. As a result, mutant M315F was found to efficiently synthesize Rh2 (~99%) and block the further glycosylation of C12-OH. The circulation of UDPG was achieved by combining M315F with AtSuSy through a cascade reaction. Furthermore, an extraordinarily high yield of Rh2 (3.7 g/L) was attained in an aqueous solvent system with 17% DMSO (v/v) through the fed-batch feeding of PPD. This study presents the high potential for the oriented preparation of ginsenoside Rh2. [ABSTRACT FROM AUTHOR]

We propose a composite acousto-optical modulation (AOM) scheme for wide-band, efficient modulation of CW and pulsed lasers. We show that by adjusting the amplitudes and phases of weakly-driven daughter AOMs, diffraction beyond the Bragg condition can be achieved with exceptional efficiencies. Furthermore, by imaging pairs of AOMs with opposite directions of sound-wave propagation, high contrast switching of output orders can be achieved at the driving radio frequency (rf) limit, thereby enabling efficient bidirectional routing of a synchronized mode-locked laser. Here we demonstrate a simplest example of such scheme with a double-AOM setup for efficient diffraction across an octave of rf bandwidth, and for routing a mode-locked pulse train with up to f rep  = 400 MHz repetition rate. We discuss extension of the composite scheme toward multi-path routing and time-domain multiplexing, so as to individually shape each pulses of ultrafast lasers for novel quantum control applications.

Dipole spin-wave states of atomic ensembles with wave vector k(ω) mismatched from the dispersion relation of light are difficult to access by far-field excitation but may support rich phenomena beyond the traditional phase-matched scenario in quantum optics. We propose and demonstrate an optical technique to efficiently access these states. In particular, subnanosecond laser pulses shaped by a home-developed wideband modulation method are applied to shift the spin wave in k space with state-dependent geometric phase patterning, in an error-resilient fashion and on timescales much faster than spontaneous emission. We verify this control through the redirection, switch off, and recall of collectively enhanced emission from a ^{87}Rb gas with ∼75% single-step efficiency. Our work represents a first step toward efficient control of electric dipole spin waves for studying many-body dissipative dynamics of excited gases, as well as for numerous quantum optical applications.

Advances of quantum control technology have led to nearly perfect single-qubit control of nuclear spins and atomic hyperfine ground states. In contrast, quantum control of strong optical transitions, even for free atoms, are far from being perfect. Developments of such quantum control appears to be limited by available laser technology for generating isolated, sub-nanosecond optical waveforms with 10's of GHz programming bandwidth. Here we propose a simple and robust method for the desired pulse shaping, based on precisely stacking multiple delayed picosecond pulses. Our proof-of-principal demonstration leads to arbitrarily shapeable optical waveforms with 30 GHz bandwidth and 100 ps duration. We confirm the stability of the waveforms by interfacing the pulses with laser-cooled atoms, resulting in "super-resolved" spectroscopic signals. This pulse shaping method may open exciting perspectives in quantum optics, and for fast laser cooling and atom interferometry with mode-locked lasers.

Curcumin is an active ingredient with multiple functions, but its application is often restricted due to its poor water solubility, weak stability, and consequently low bioaccessibility. Based on this, the aim of this work is to develop a new vehicle to overcome these restrictions. Here we developed a curcumin-loaded nanoemulsion and then curcumin-loaded silica-lipid hybrid microparticles through emulsification and vacuum drying, respectively. The loading of curcumin in the nanoemulsion and microparticles was (0.30±0.02) and (0.67±0.02) %, respectively. FTIR and XRD analyses of microparticles revealed that curcumin was encapsulated in porous, amorphous silica. In vitro antioxidant activities showed that the encapsulation would not affect the antioxidant activity of curcumin. In vitro simulated digestion indicated that nanoemulsion and microparticles had higher curcumin bioaccessibility than the control group. The storage stability of microparticles remained the same during 6 weeks in the dark at 4, 25 and 40 °C. Moreover, the microparticles had a better chemical stability than nanoemulsion under the light. The cell viability was over 80% when the concentration of nanocarriers was less than 45 μg/mL. Hence, the microparticles could be a promising means to load curcumin and improve its solubility, light stability and bioaccessibility., Competing Interests: CONFLICT OF INTEREST: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Topical administration of anticancer drugs provides a potential chemotherapeutic modality with high patient compliance for cutaneous melanoma. However, the drug delivery efficiency is highly limited by physiological barriers from the skin to the tumor, which cannot acquire desired therapeutic efficacy. Herein, we propose a paintable oligopeptide hydrogel containing paclitaxel (PTX)-encapsulated cell-penetrating-peptide (CPP)-modified transfersomes (PTX-CTs) to enhance transdermal PTX delivery for topical melanoma treatment. After being plastered on the skin above the melanoma tumor, the PTX-CTs-embedded hydrogel (PTX-CTs/Gel) as a patch provided prolonged retention capacity of the PTX-CTs on the skin. The PTX-CTs with superior deformability could efficiently squeeze through the channels in the stratum coreum, and the surfactant components improved the fluidity of the lipid molecules in the stratum corneum to further enhance the skin permeation. Moreover, the CPP modification rendered the PTX-CT-enhanced penetration in the skin and tumor stroma as well as efficient transportation in the tumor cells. The PTX-CTs were shown to effectively slow the tumor growth in combination with the systemic chemotherapy using Taxol, the commercial PTX formulation on the xenograft B10F16 melanoma mouse model.