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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]

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]