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Water is the important medium of the tea infusions, which plays a crucial role in the development of tea quality. Tooma sinensis (TS) fermented tea was brewed with tap water, mineral water and purified water. The physicochemical indexes, biochemical components, antioxidant activity and flavor compounds of three types tea infusions were analyzed using ultraviolet spectrophotometer, electronic tongue and gas chromatography-mass spectrometry (GC-MS) to elucidate the influence of different brewing water on the quality of TS fermented tea infusions. The results demonstrated that the quality and antioxidant activity of TS fermented tea infusions were significant influenced by different brewing water (P

To investigate the effect of drying methods on the volatile flavor substances of Toona sinensis, the volatile components of vacuum freeze-dried, heat pump-dried, hot air-dried, and microwave vacuum-dried Toona sinensis samples were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS) and gas chromatography-mass spectrometry (GC-MS) coupled with relative odor activity values, and the differences of volatile components among samples were further explored by combining the stoichiometric principal component analysis and partial least square discriminant analysis. The results showed that 78 peaks were detected and 59 compounds were identified by GC-IMS. 94 kinds of volatile compounds were identified by GC-MS, and the main volatile components were sulfides, olefins and aldehydes. The content of total volatile compounds was significantly reduced after drying. The key aroma compounds in Toona sinensis samples were identified by ROAV method, such as (E,Z)-di-1-propenyldisulfide, 2-mercapto-3,4-dimethyl-2,3-dihydrothiophene, hexanal, 2-hexenal and eugenol. The PCA and PLS-DA results showed that the samples with different drying methods were not only clearly separated from the raw samples, but also significantly different from each other. The raw samples and vacuum freeze-dried samples were grouped, and the other three dried Toona sinensis samples were grouped. According to the variable importance in projection score, a total of 10 (VIP>1) labeled volatile compounds were selected. The drying method had significant effect on the flavor characteristics of Toona sinensis, and the vacuum freeze-dried group was the closest to the raw sample, while heat pump-drying was the most suitable dehydration method for Toona sinensis, considering the practical application. This study provides some theoretical references for flavor quality control in the thermal processing process.

In order to explore the antibacterial material basis from the root bark of Ailanthus altissima, the silica gel and Sephadex LH-20 were employed to separate and purify methanol extract from the root bark of the A. altissima, and the structures of the compounds were identified by chemical properties and spectral data. Flow cytometry was employed to test the antibacterial activity of the compounds, and kanamycin was used as control group. The results were as follows: Twenty-two compounds were isolated and elucidated from the root bark of A. altissima respectively as pleuchiol (1), withastramonolide (2), 7-ketositosterol (3), betulin (4), betulinic acid methyl ester (5), 1, 2, 4-trimethoxybenzene (6), dimethyl maleate (7), sonderianol (8), dibutyl phthalate (9), pinoresinol (10), p-hydroxybenzoic acid ethyl ester (11), avenalumic acid methyl ester (12), 5, 3′-dihydroxy-3,7, 4′-trimethoxyflavone (13), spathulenol (14), 2-methyl-5-acetonyl-7-hydroxychromone (15), 7, 4′-dihydroxyflavone (16), annphenone (17), 3-hydroxy-4-methoxybenzoic acid (18), 5, 3′,4′-trihydroxy-7-methoxyflavanone (19), dibutyl phthalate (20), 4-O-methylgallic acid (21), dioctyl terephthalate (22). All compounds were isolated from the root bark of A. altissima for the first time. The antibacterial activity tests showed that Compound 2 had inhibitory effect on Pseudomonas aeruginosa and Bacillus subtilis. Compound 3 had inhibitory effects on Bacillus subtilis. Compound 8 had inhibitory effects on Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis. Compound 17 had inhibitory effects on Pseudomonas aeruginosa and Staphylococcus aureus. The inhibitory effect of Compound 2 on Bacillus subtilis was not significantly different from kanamycin (P>0.05). This paper aims to clarify the antibacterial substance basis of the root bark of A. altissima, and provide a certain theoretical basis for the development and utilization of the root of A. altissima resources and the research and development of drugs with antibacterial activity.

Objective: Single factor experiment and response surface methodology were used to optimize the ultrasonic extraction of oridonin from Rabdosiaru bescens and the antitumor effect in vitro was studied. Methods: Three key factors including solid-liquid ratio, ultrasonic time, ultrasonic power were selected by one-factor-at-a-time experiments. HepG2 cells were cultured in vitro. The antitumor activity of oridonin was investigated by studying the survival rate of HepG2 cells and the expression of apoptotic proteins caspase-3 and caspase-9. Results: The optimum conditions of ultrasonic extraction of oridonin from Rabdosiaru bescens were as follows: Solid-liquid ratio was 1:18 g/mL, ultrasonic time was 1.5 h at 190 W ultrasonic power, the extraction yield of oridonin reached 4.122%±0.102%. In vitro, oridonin could significantly reduced the survival rate of HepG2 cells and increased the expression of caspase-3 and caspase-9. And when the concentration of oridonin exceeds 8 μmol/L, the survival rate and apoptotic protein of hepatoma cells were significantly affected (P

Objective: To analyze the clinicopathological characteristics of skin basal cell carcinoma, so as to improve the coincidence rate of clinical diagnosis and provide basis for early diagnosis, treatment and prognosis. Methods: The clinical and pathological features of 611 patients with basal cell carcinoma diagnosed by primary biopsy in Dermatology Hospital, Southern Medical University from March 2014 to February 2021 were retrospectively analyzed. Results: There were 268 males and 343 females in 611 patients, the ratio of male to female was 1 ∶1.28; the onset age was 19~92 (64.18±13.90) years old. There were 296 cases (48.45%) with mass, nodule and tumor, 248 cases (40.59%) with patch and papule, and 67 cases (10.97%) with erosion or ulcer, scar and cyst. Pathological classification: nodular type 377 cases (61.71%), infiltrative type 85 cases (13.92%), superficial type 69 cases (11.30%), other types 80 cases (13.10%). Clinical misdiagnosis rate was 16.86%. Conclusions: The main clinical manifestation is mass, and the main pathological type is nodule. It is important to improve the diagnosis, treatment and prognosis of BCC by improving the rate of skin biopsy and strengthening the understanding of easily misdiagnosed lesions.

Routing protocols could achieve efficient convergecast transmission of sensed data in cognitive radio sensor network (CRSN),and it is of vital importance for the whole network performance.In particular,cluster-based routing protocols could further lower routing selection complexity and improve scalability.Therefore,an overview of cluster-based routing protocols for CRSN was provided.Firstly,after a brief introduction to the concept and advantages of clustering in CRSN,the major factors concerning clustering algorithm design were pointed out.Secondly,the challenges faced by routing protocol design in CRSN and basic design principles were explored.Thirdly,the previous work of cluster-based routing protocols for CRSN was systematically analyzed and summarized.Finally,issues that require urgent solutions and future research directions were suggested.