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The calyx of Physalis alkekengi is rich in various bioactive components. In this study, ultrasonic assisted ethanol solvent was used to extract the total flavonoids using calyx of Physalis alkekengi as materials, and the effects of ultrasonic power, extraction temperature, ultrasonic time, ethanol volume fraction and solid -liquid ratio on the yields of total flavonoids were investigated, then the L16(45) orthogonal test was used to further optimize the extraction parameters on the basis of single factor experiments, in order to efficiently and fully extract the total flavonoids. The results showed that the optimal extraction process was determined as follows: ultrasonic power of 180 W, extraction temperature of 60 °C, 60% ethanol solution soaked for 24 h with solid-liquid ratio of 1:20(g/mL), and ultrasonic time of 50 min. Under these conditions, the yield of total flavonoids was 2.982%. The process in this paper is simple with low preparation cost, which is convenient for industrial production and helpful to the comprehensive utilization and development for calyx of Physalis alkekengi. [ABSTRACT FROM AUTHOR]

Aim This study aimed to investigate the high-resolution phenotypic and genotypic characterization of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli strains isolated from hospitalized patients to explore the resistance genes and mobile genetic elements (MGEs) involved in horizontal dissemination. Methods Between May and September 2021, a total of 216 ESBL-producing E. coli isolates were recovered from multiple departments. The identification of strains was performed using MALDI-TOF mass spectrometry and PCR, while antibiotic susceptibility testing was carried out using the Vitek 2 COMPACT system to determine resistance patterns, while PCR was used to detect different resistance genes and MGEs. In addition, a conjugation assay was performed to investigate the horizontal gene transfer of resistance genes. Selected isolates underwent whole-genome sequencing (WGS) using the Illumina MiSeq platform. Results A total of 216 out of 409 E. coli isolates recovered from a tertiary hospital were observed to be ESBL-producing, giving a carriage rate of 52.8%, as determined by phenotypic screening. The most frequent sources of ESBL-producing E. coli isolates were urine (129/216, 59.72%) and blood (50/216, 23.14%). The most prevalent ESBL genes identified were bla CTX-M (60.18%), bla TEM (40.27%), and bla SHV (18.05%). Three E. coli isolates were found to carry the genes bla NDM, mcr-1 , and fosA3 genes. The most prevalent MGEs were IS 26 (95.37%), Int (87.03%), and IncFIB (76.85%). WGS analysis of eight MDR E. coli strains revealed that these isolates belonged to eight different sequence types (STs) and serotypes and were found to harbor multiple plasmid replicons and virulence factors. Conclusion This study highlights a high incidence of antibiotic resistance genes and MGEs associated with the dissemination of ESBLs and other resistance genes. [ABSTRACT FROM AUTHOR]