Lingyu Kong

Objective: This study aimed to establish a high-performance liquid chromatography (HPLC) method for the simultaneous quantification of six components in Zhuqi Piantan Granules, and to investigate the protective effect and underlying mechanism of Zhuqi Piantan Granules alone or combined with electroacupuncture on cerebral ischemia-reperfusion injury in rats. Methods: Zhuqi Piantan Granules were extracted with 80% methanol. HPLC analysis employed a C18 column and gradient elution using acetonitrile and 0.3% phosphoric acid as the mobile phase. Modeled rats were randomly grouped, given corresponding interventions for 14 days, and evaluated for neurological function, cerebral infarct ratio, vascular density, brain histological changes (hematoxylin-eosin (HE) staining), and Angiopoietin-1/Tyrosine Kinase Receptor-2(Ang-1/Tie-2) protein expressions (Western Blotting). Results: All six target components exhibited excellent linear relationships (r ≥ 0.9994). The average recoveries ranged from 97.1% to 99.5%. Both Zhuqi Piantan Granules alone and their combination with electroacupuncture improved neurological function, reduced infarct ratio, increased vascular density, alleviated brain pathological damage, and upregulated Ang-1/Tie-2 expressions—with the combined treatment showing superior efficacy. Conclusion: The established HPLC method is reliable and suitable for Zhuqi Piantan Granules quality control. Zhuqi Piantan Granules alone or combined with electroacupuncture alleviates rat cerebral injury by activating the Ang-1/Tie-2 pathway to promote angiogenesis.

The purpose of this study is to design a flower-shaped lactose loaded curcumin solid lipid nanoparticles dry powder inhaler and characterize it to improve the solubility and dissolution rate of curcumin in lung. Curcumin solid lipid nanoparticles (Cur-SLNs) were prepared by solvent evaporation method, and then they were micronized by freeze-drying technology. Finally, Cur-SLN micropowder obtained by freeze-drying was mixed with flower-shaped lactose (FL) at a ratio of 2:1 and then passed through a 200-mesh sieve to obtain Cur-SLN-FL powder. Tween-80 was selected as the surfactant to inhibit the aggregation of drug solid lipid nanoparticles. Under the optimum conditions, the solid lipid nanoparticles (SLN) were relatively spherical, with an average particle size of 14.7nm, narrow distribution, Zeta potential of 22.5mV, encapsulation efficiency of 90.21, and drug loading of 8.56. According to the particle size, PI, Zeta potential, drug loading (LC), encapsulation efficiency (EE), morphology, and in vitro release characteristics, the prescription of solid lipid nanoparticles was screened. Dry powder inhaler (DPI) was characterized by differential scanning calorimetry, scanning electron microscopy, particle size, density, and in vitro release performance. Its cytotoxicity to mouse fibroblasts (L929) and human normal lung epithelial cells (BEAS-2B) in vitro was investigated, and its safety for pulmonary inhalation was preliminarily determined. FTIR analysis shows that the micronized Cur-SLN-FL has the same chemical structure as FL. FTIR and DSC analysis confirmed that the characteristic absorption peak of curcumin was not found in Cur-SLN-FL, showing similar structure to SLN and FL. In addition, curcumin was coated in solid lipid nanoparticles to make powder mist, which increased its drug loading, kept its aerodynamic particle size (4.03±0.40)μm, and significantly improved its drug release performance in artificial lung fluid. In vitro cytotoxicity test results confirmed that Cur-SLN-FL was less toxic to BEAS-2B cells than L929 cells. Therefore, curcumin was prepared into solid lipid nanoparticles by emulsion evaporation-low temperature solidification method and then micronized and mixed with FL to prepare curcumin solid lipid nanoparticle powder mist loaded with flower-shaped lactose. The process is simple and feasible, and it has better safety performance for lung cells, which is expected to become a safe and effective delivery system for pulmonary inhalation drugs.

The development of spray drying technology has been widely used for drying and preservation of food products. Though infant milk powder iron fortification is necessary for infants and children, iron fortification is accompanied by some limitations that reduce its quality and oxidation of Fe2+ into Fe3+, causing sensory problems and even a decrease in iron absorption, which does not meet the normal requirements of infant and child body development. To overcome this adverse effect and to improve the bioavailability of iron, a spray drying method was used to simulate the milk powder production process by codrying a mixture of ascorbic acid and ferrous sulfate, where ascorbic acid was uniformly coated on the outer layer of ferrous sulfate. It was demonstrated that ascorbic acid had a very obvious inhibitory effect on the oxidation of ferrous iron and could maintain the stability of ferrous iron in solid and solution for a long time, thus improving the bioavailability of iron.

Bacteriocins produced by lactic acid bacteria have potential use as natural food preservatives, which may alleviate current problems associated with the overuse of antibiotics and emerging multi-drug-resistant microbes. In this work, Lactiplantibacillus plantarum RUB1 was found to produce a class IIb bacteriocin with strong antibacterial activity. Except for plnXY encoding putative proteins, L. plantarum RUB1 contains most genes in five operons (plnABCD, plnGHSTUVW, plnMNOP, plnIEF, and plnRLJK) related to bacteriocin synthesis. Adding low (100 and 500 ng/mL) and medium (1 μg/mL) concentrations of PlnA to broth promoted bacteriocin production and upregulated bacteriocin gene plnA, while high concentrations (50 and 200 μg/mL) inhibited expression of these genes. Co-culturing L. plantarum RUB1 with Enterococcus hirae 1003, Enterococcus hirae LWS, Limosilactobacillus fermentum RC4, L. plantarum B6, and even Listeria monocytogenes ATCC 19111 and Staphylococcus aureus ATCC 6538 enhanced bacteriocin activity and expression of bacteriocin-related genes. This study verifies that PlnA can indeed upregulate the expression of bacteriocin genes, and also bacteriocin production can be induced by co-culture with some specific bacteria or their cell-free supernatants. Bacteriocin production by L. plantarum RUB1 is mediated by a quorum sensing mechanism, directly influenced by autoinducing peptide or specific strains. The findings provide new methods and insight into bacteriocin production mechanisms.