Enhanced antibacterial efficacy and mechanism of octyl gallate/beta-cyclodextrins against Pseudomonas fluorescens and Vibrio parahaemolyticus and incorporated electrospun nanofibers for Chinese giant salamander fillets preservation.

A series of alkyl gallates were evaluated for the antibacterial activity against two common Gram-negative foodborne bacteria (Pseudomonas fluorescens and Vibrio parahaemolyticus) associated with seafood. The length of the alkyl chain plays a pivotal role in eliciting their antibacterial activities and octyl gallate (OG) exerted an excellent inhibitory efficacy. To extend the aqueous solubility, stability, and bactericidal properties of octyl gallate (OG), an inclusion complex between OG and ß-cyclodextrin (ßCD), OG/ßCD, was prepared and identified with various methods including X-ray diffraction (XRD), differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). Furthermore, the enhanced inhibitory effect and potential antibacterial mechanism of OG/ßCD against two Gram-negative and Gram-positive foodborne bacteria were comprehensively investigated. The results show that OG/ßCD could function against bacteria through effectively damaging the membrane, permeating into cells, and then disturbing the activity of the respiratory electron transport chain to cause the production of high-level intracellular hydroxyl radicals. Moreover, the reinforced OG/ßCD-incorporated polylactic acid (PLA) nanofibers were fabricated using the electrospinning technique as food packaging to extend the Chinese giant salamander fillet's shelf life at 4 °C. This research highlights the antibacterial effectiveness of OG/ßCD in aqueous media, which can be used as a safe multi-functionalized food additive combined with the benefits of electrospun nanofibers to extend the Chinese giant salamander fillets shelf life by 15 d at 4 °C.

Nano/Micro-Structured Si/C Anodes with High Initial Coulombic Efficiency in Li-Ion Batteries.

One of the major challenges for designing high-capacity anode materials is to combine both Coulombic efficiency and cycling stability. Herein, nano/micro-structured Si/C composites are designed and synthesized to address this challenge by decreasing the specific surface area and improving the tap density of Si/C materials. An ultrahigh initial Coulombic efficiency of 91.2 % could be achieved due to a proper particle size, low specific surface area, and optimized structure. The nano/micro-structured Si/C anodes exhibit excellent cycling stability with 96.5 % capacity retention after 100 cycles under a current density of 0.2 A g(-1) .