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Alzheimer′s disease(AD) is a widely recognized chronic neurodegenerative condition.Drosophila, with its well-defined genetic structure, straightforward experimental methodologies, and the presence of human disease-related genes or highly similar homologous genes, serves as an advantageous model organism.The utilization of Drosophila′s renowned Galactose-regulated Upstream Promoter Element 4-Upstream Activating Sequence(GAL4-UAS) system has led to the development of various AD models.These models facilitate the exploration of AD′s molecular mechanisms and the advancement of drug discovery efforts.This paper reviews the foundational principles, methodologies, and diverse applications of different AD Drosophila models, offering insights and innovative approaches for AD research utilizing Drosophila.

In this study, persimmon wine was brewed with fresh persimmon pulp (S), frozen persimmon pulp (D), persimmon peel (P), and persimmon pulp treated with tannins (M) under the same conditions. Tannin content and the microbial community structure and diversity during fermentation were analyzed separately in order to analyze dynamic changes to the tannin content and microbial community during the fermentation of persimmon wine following pretreatment with different raw materials and to analyze the differences and correlations between the various raw materials in order to provide a theoretical basis for the later regulation of tannin content in persimmon wine. The results showed that, in all four pretreatments, the tannin content showed a trend of increasing and then gradually decreasing during fermentation, but the tannin content in persimmon wine made from persimmon pulp (M) treated with tannase was always at the lowest tannin content of all the pre-treatments. At the level of the bacterial community structure, the dominant phylum was cyanobacteria on the first day of fermentation, while the dominant phyla from the third day to the ninth day were Firmicutes and Proteobacteria. At the genus level, the dominant phyla varied, with the most frequent phyla being Pediococcus (S), Leuconostoc (D), Acinetobacter (P), Gluconobacter and Pediococcus (M), respectively. At the level of the fungal community, the Cysticercus phylum was dominant. At the genus level, the dominant genera was Saccharomycopsis for all treatments. Persimmon wine with different pre-treatments had a stronger similarity in terms of their fungi during fermentation than in terms of their bacteria. In addition, fresh persimmon pulp (S), frozen persimmon pulp (D), persimmon peel (P), and persimmon pulp fermented by tannase (M) showed significant correlations between tannin content and microbial genera in the fermentation of species 10, 5, 3, and 7, respectively, with different microbial genera. Preliminarily, the raw material pretreatment would affect the tannin content and microbial correlation during the fermentation of persimmon wine.

In this study, deep eutectic solvents (DESs) coupled with ultrasound-assisted extraction (UAE) were applied to extract polyphenol from chestnut shells and the components were identified. Eight different DESs were evaluated as candidate solvents and fourier transform infrared spectroscopy (FTIR) was performed to confirm the formation of hydrogen bonds between hydrogen bond acceptor and hydrogen bond donor. Based on the single factor experiments, the response surface methodology (RSM) was applied, ultrasonic power, liquid-solid ratio and water content were further evaluated in order to optimize the total ployphenol yield. Besides, the extracts were recovered by macroporous resin for the identification of phenolic compounds. As a result, DES-1 (choline chloride:oxalic acid=1:1) exhibited a highest extraction yield. After that, DES-1-based UAE process was optimized and the optimal conditions were as follows: Ultrasonic power 348 W, liquid-solid ratio 42:1 mL/g and water content 32%. The extraction yield (99.66±2.63) mg/g of the model validation experiment was demonstrated to be in accordance with the predicted value 99.44 mg/g, which was significantly higher than that obtained by using traditional solvents (water and 40% ethanol). In addition, phenolic compounds was efficiently recovered from DES extracts with high recovery yield (97.92%±1.78%) by using AB-8 macroporous resin. 13 phenolic compounds were preliminarily identified from DES-1-based UAE extracts by UHPLC-Q-TOF-MS/MS. In conclusion, this study would provide a green and efficient method to extract polyphenols from chestnut shells, providing technical support for the development and utilization of chestnut shells waste.

A novel pH-sensitive carboxymethyl chitosan graft polyacrylic acid(CMC-g-PAA) hydrogel is fabricated via a free radical heat-initiated graft copolymerization reaction with acrylic acid(AA) and carboxymethyl chitosan(CMC) as monomers. The polymerization is successful, which is confirmed via fourier transform infrared spectroscopy (FT-IR). The result of swelling experiment indicates that the final CMC-g-PAA hydrogel has significant pH-sensitivity. Insulin(INS), as a model drug, is loaded into the hydrogel and 216.5 mg/g incorporation of INS is obtained. In vitro release profiles suggest that INS release is (16.3±2.6)% when pH is 1.2 after 2 h. INS release is (57.2±3.5)% in PBS with pH of 7.4 after the next 2 h. The study indicates that the CMC-g-PAA hydrogel loaded with INS could targeted deliver INS in intestinal, and avoid that INS is destroyed by gastric acid and pepsin. The experiment result on animals indicates that the CMC-g-PAA hydrogel loaded with INS has hypoglycemic effects. With different concentrations of CMC-g-PAA hydrogel co-cultured with Caco-2 cells, the cell survival rates are close to 100%, which indicates that the hydrogel has no cytotoxicity. In sum, the novel CMC-g-PAA hydrogel has a prospective application in the specific-site delivery of proteins and peptides.

This study was performed to investigate the inhibitory mechanisms of 3 plant polyphenols, grape seed extract (GSE), lotus seed proanthocyanidins (LSPC) and lotus root polyphenol extract (LRPE), against Shewanella putrefaciens. Their antibacterial effects were determined in terms of minimum inhibitory concentration (MIC) and the growth curve of S. putrefaciens. By scanning electron microscopy (SEM), relative conductivity, propyridine iodide (PI) staining, alkaline phosphatase (AKP) activity, extracellular protein content, nucleic acid leakage, Na+ K+ -ATPase activity and membrane protein fluorescence analysis, the antibacterial mechanism was explored. The results showed that the MICs of GSE, LRPE and LSPC were 31.25, 62.25 and 125.00 μg/mL, respectively. After S. putrefaciens was treated with the polyphenols, the position of membrane proteins was changed, the fluorescence intensity was reduced, the morphology was altered, the surface became wrinkled and sunken, and the growth was significantly inhibited. In addition, the activity of extracellular AKP, the contents of nucleic acid and extracellular protein in the bacterial suspension, relative conductivity and PI intake were significantly increased, and Na+ K+-ATPase was inactivated to a certain extent, thereby leading to cell death.

Purpose: To investigate the inhibitory effects of grapefruit seed extract (GSE) and its nanoemulsion (GNE) on biofilm formation of Escherichia coli and Staphylococcus aureus. Methods: The inhibitory effects of GSE and GNE on the formation of single and mixed-species biofilms were explored by analyzing the changes in the number of adherent cells and the content of extracellular polymeric substances (EPS) as well as microstructure observation, and the effectiveness of GSE and GNE in eliminating biofilms formed by E. coli and S. aureus was compared. Results: The number of adherent cells and EPS production during single-species biofilm formation were inhibited by GSE and GNE at 1/2 minimum inhibitory concentration (MIC), and S. aureus was more strongly inhibited. The changes of biofilm microstructure observed under a scanning electron microscope (SEM) and a confocal laser scanning microscope (CLSM) confirmed the inhibitory effect of GSE and GNE on biofilm formation by the two bacteria. GSE and GNE could also eliminate E. coli and S. aureus biofilms, and were more effective for S. aureus biofilm, but the resistance of the mixed-species biofilms was stronger than that of the single-species biofilms. GNE was more effective than GSE in inhibiting biofilm formation and eliminating biofilms. The amount of single-species biofilms formed by the two bacteria decreased by 0.6 (lg (CFU/cm2)) when treated with GNE at 1/2 MIC for 120 h compared with GSE, and the elimination rate of biofilms by 1.8% GNE increased by 7.7%–27.2% compared with GSE. Conclusion: GSE and GNE have inhibitory effect on on biofilm formation of Escherichia coli and Staphylococcus aureus. This study can provide a scientific basis for the application of GSE and GNE in biofilm control.