Plant Growth-Promoting Rhizobacteria Are Key to Promoting the Growth and Furanocoumarin Synthesis of Angelica dahurica var. formosana under Low-Nitrogen Conditions.

Microbiomes are the most important members involved in the regulation of soil nitrogen metabolism. Beneficial interactions between plants and microbiomes contribute to improving the nitrogen utilization efficiency. In this study, we investigated the Apiaceae medicinal plant Angelica dahurica var. formosana. We found that under a low-nitrogen treatment, the abundance of carbon metabolites in the rhizosphere secretions of A. dahurica var. formosana significantly increased, thereby promoting the ratio of C to N in rhizosphere and nonrhizosphere soils, increasing carbon sequestration, and shaping the microbial community composition, thus promoting a higher yield and furanocoumarin synthesis. Confirmation through the construction of a synthetic microbial community and feedback experiments indicated that beneficial plant growth-promoting rhizobacteria play a crucial role in improving nitrogen utilization efficiency and selectively regulating the synthesis of target furanocoumarins under low nitrogen conditions. These findings may contribute additional theoretical evidence for understanding the mechanisms of interaction between medicinal plants and rhizosphere microorganisms.

AgNPs/nGOx/Apra nanocomposites for synergistic antimicrobial therapy and scarless skin recovery.

The misuse of antimicrobials has caused a remarkable increase of antibiotic-resistant bacteria. Developing novel antimicrobial agents with high activity and low rates of resistance development is in great demand yet challenging. In this context, we developed a novel cascaded AgNPs/nGOx/Apra nanocomposite for combinational antimicrobial therapy. Glucose oxidase nanocapsules (nGOx) in the nanocomposites can convert tissue glucose into H2O2, which in turn accelerates the erosion of AgNPs into Ag+, giving rise to a synergistic antibiotic/starving-like/metal ion therapeutic effect. An in vitro antimicrobial study of the nanocomposites demonstrated rapid bacterial killing, significant bacterial growth inhibition and broad antimicrobial spectra at a low antibiotic dose. More importantly, topical and microneedle-assisted deliveries of the nanocomposites resulted in rapid scarless skin recovery in both rabbit and mouse models. This nanocomposite platform opens up a new avenue for research and clinical applications to battle against microbial infections and reduce antibiotic-resistant rates.

Ultrasonication-assisted synthesis of alcohol-based deep eutectic solvents for extraction of active compounds from ginger.

An ultrasonication-assisted synthesis of alcohol-based deep eutectic solvents (DESs) is described. Several DESs were synthesized simultaneously under the same conditions. The prepared DESs were used for the extraction of gingerols from ginger powder via ultrasonication-assisted extraction. Notably, some of the prepared DESs exhibited superior extraction performance than those in traditional organic solvents. The viscosity of the DESs, which was suggested to be typically lower than 100 mPa*s had a critical effect on extraction performance. However, the higher gingerol contents in the extracts did not translate to higher active antioxidant abilities. The extraction temperature was found to be a key determinant of the antioxidant capability of the extracted gingerols while the use of higher temperatures (>50 °C) induced degradation and loss of phenolic compounds during extraction. Response surface methodology was applied for determining the optimal extraction conditions to achieve maximum antioxidant capacity with suitable gingerol content. All compounds used for the preparation of the DESs in this study have been widely employed in cosmetic and pharmaceutical fields. Therefore, the extracts in these DES solutions can be considered for direct application development without further product isolation.