ABSTRACT
An effective approach to extracting four flavonoids (lysioside C, nevadensin-7-sambubioside, ikarisoside B, and nevadensin) from Lysionotus pauciflorus using ultrasonic-assisted aqueous two-phase extraction (UAATPE) technology was studied. Ethanol/K2HPO4 system was selected and the influence of several important parameters, including composition of the aqueous two-phase system (ATPS), extraction temperature and time, particle size, and solvent to material ratio, were investigated by single factor experimentss. Then three key parameters (ethanol concentration, solvent to material ratio and extraction temperature) were further optimized by response surface methodology (RSM). The optimal process was that 1 g 120 mesh herb powders were extracted with 45 g ATPS (made of 30% ethanol/18% K2HPO4) in 43 °C for 30 min, and yields of four flavonoids could reach 2.56, 2.06, 3.62, and 6.28 mg/g, respectively. Compared with ultrasonic-assisted extraction (UAE) in three conventional solvents (water, ethanol and 60% ethanol), the UAATPE displayed comparatively higher extraction capability. Therefore, UAATPE in ethanol/K2HPO4 system could be an alternative technology for integrated extraction of the flavonoids from L. pauciflorus.
Subject(s)
Flavonoids , Lamiales , Plant Extracts , Ultrasonics , Ethanol , Solvents , WaterABSTRACT
OBJECTIVES: A pneumonia associated with 2019 novel coronavirus (2019-nCoV, subsequently named SARS-CoV2) emerged worldwide since December, 2019. We aimed to describe the epidemiological characteristics of 2019 coronavirus disease (COVID-19) in Shaanxi province of China. RESULTS: 1. Among the 245 patients, 132 (53.9%) were males and 113 (46.1%) were females. The average age was 46.15 ± 16.43 years, ranging from 3 to 89 years. 2. For the clinical type, 1.63% (4/245) patients were mild type, 84.90% (208/245) were moderate type, 7.76% (19/245) were severe type, 5.31% (13/245) were critical type and only 0.41% (1/245) was asymptomatic. 3. Of the 245 patients, 116 (47.35%) were input case, 114 (46.53%) were non-input case, and 15 (6.12%) were unknown exposure. 4. 48.57% (119/245) cases were family cluster, involving 42 families. The most common pattern of COVID-19 family cluster was between husband and wife or between parents and children.
Subject(s)
Coronavirus Infections/prevention & control , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Quarantine , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , COVID-19 , Child , Child, Preschool , China/epidemiology , Cluster Analysis , Coronavirus Infections/epidemiology , Female , Humans , Male , Middle Aged , Pneumonia, Viral/epidemiology , Retrospective Studies , Sex Factors , Young AdultABSTRACT
Two new stilbenoids bletilol D (1) and bletilol E (2), together with five known compounds were isolated from Bletilla striata. Three of them (3, 4, and 7) were obtained from this genus for the first time. Their structures were elucidated by spectroscopic methods and comparing with data reported in literatures. The cytotoxic activities of compounds 1-7 against MCF-7 (human breast cancer) and A549 (human lung carcinoma) cell lines were evaluated by MTT assay. Compound 2 showed weak cytotoxicity against MCF-7 and A549 cell lines with IC50 values of 36.32 ± 1.17 and 36.48 ± 1.12 µM, respectively, and 5 exhibited weak cytotoxicity against MCF-7 cell line with IC50 value of 57.09 ± 2.03 µM.