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2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Yaqian Zhang ◽  
Yuqiao Yang ◽  
Ye Shang ◽  
Chunxiao Liang ◽  
Jun He ◽  
...  

The objective of this work was to provide an economic and practical method for the purification of columbianetin-β-D-glucopyranoside from Angelicae Pubescentis Radix extract. In the static adsorption and desorption, the effects of resin type (D101, HP-20, AB-8, GDX-201, and DA201), contact time (10–360 min), and temperature (298–318 K) were assessed on columbianetin-β-D-glucopyranoside adsorption efficiency in laboratory. GDX-201 resin showed the best adsorption and desorption properties for columbianetin-β-D-glucopyranoside. The kinetic data revealed that the equilibrium time for columbianetin-β-D-glucopyranoside adsorption was achieved within 150 min. Moreover, the adsorption kinetic curve was well in accordance with the pseudo-second-order equation (R2 > 0.99). The rate controlling step of the adsorption process was the intraparticle diffusion. The Langmuir isotherm models (R2 > 0.99) could describe the whole adsorption process, which was exothermic and spontaneous according to the result of thermodynamics tests. In the dynamic adsorption and desorption process, the optimum loading flow (4, 5, and 6 BV/h), ethanol concentration (0–60%), and elution volume (10–230 mL) were optimized. Under optimal conditions of 4 BV/h loading flow, 6.7 BV loading volume, 25% ethanol, and 14 BV elution volume, the content of columbianetin-β-D-glucopyranoside in the product was increased 29.61-fold from 0.45% to 13.32 ± 0.64% with yield of 88.03 ± 2.76% by an experiment of lab-scale enlargement. Then, columbianetin-β-D-glucopyranoside was further purified by PHPLC and its purity was more than 98%. Additionally, the analgesic activity of the columbianetin-β-D-glucopyranoside was assessed by hot plate test. The experimental results showed that columbianetin-β-D-glucopyranoside significantly increased the latency of pain response in mice. This study demonstrated columbianetin-β-D-glucopyranoside could be as a potentially natural analgesic component. It could be summed up that the established method was successfully applied to purifying columbianetin-β-D-glucopyranoside from Angelicae Pubescentis Radix extract.


2021 ◽  
Vol 5 (4) ◽  
pp. 1-5
Author(s):  
Yuhui Xu ◽  
Lize Shen ◽  
Guolin Li

Objective: To develop a cost-effective method to reduce the time consumption of elution in immunoprecipitation. Method: Two volumes (125 ?L for Group C and 100 ?L for Group T) of elution buffer were used to explore whether smaller volume could save testing time. Result: Time consumption of elution in Group T was significantly shorter than that in Group C, while the efficiency of eluted m6A-containing fragments and the performance of m6A-Seq as indicated by m6A peak distributions showed no difference between the two groups. Conclusion: A smaller volume of elution buffer was an economical way to reduce time consumption in immunoprecipitation.


Author(s):  
Mariana Fernández-Pittol ◽  
Juan Carlos Hurtado ◽  
Estela Moreno-García ◽  
Elisa Rubio ◽  
Mireia Navarro ◽  
...  

AbstractThe objective of this study was to assess the performance of direct real time RT-PCR detection of SARS-CoV-2 in heated saliva samples, avoiding the RNA isolation step. Oropharyngeal and nasopharyngeal swabs together with saliva samples were obtained from 51 patients clinically diagnosed as potentially having COVID-19. Two different methods were compared: 1. RNA was extracted from 500 μl of sample using a MagNA Pure Compact Instrument with an elution volume of 50μl and 2. 700µL of saliva were heat-inactivated at 96°C for 15 minutes, and directly subjected to RT-PCR. One step real time RT-PCR was performed using 5 μl of extracted RNA or directly from 5 μl of heated sample. RT-PCR was performed targeting the SARS-CoV-2 envelope (E) gene region. Diagnostic performance was assessed using the results of the RT-PCR from nasopharyngeal and oropharyngeal swabs as the gold standard. The overall sensitivity, specificity, positive and negative predictive values were 81.08%, 92.86%, 96.77% and 65.00%, respectively when RNA extraction was included in the protocol with saliva, whereas sensitivity, specificity, positive and negative predictive values were 83.78%, 92.86%, 68.42% and 96.88%, respectively, for the heat-inactivation protocol. However, when the analysis was performed exclusively on saliva samples with a limited time from the onset of symptoms (<9 days, N=28), these values were 90%, 87.5%, 44% and 98.75% for the heat-inactivation protocol. The study showed that RT-PCR can be performed using saliva in an RNA extraction free protocol, showing good sensitivity and specificity.


2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Fei Chang ◽  
Zhong Bing He ◽  
Quan Zhou

Four kinds of Al-TiO2 solid samples with different Ti/Al ratios of 1 : 0.1, 1 : 0.09, 1 : 0.07, and 1 : 0.05 were synthesized via a solid-phase synthesis method and characterized by XRD, SEM, EDS, BET, and other techniques. The prepared solids were used for separation of the bioderived product danshensu, the content of which was determined by UV spectrophotometry. Moreover, the effects of extract concentration, PH value, adsorption time, and ethanol elution volume were investigated. The results showed that these Al-TiO2 samples had good adsorption and desorption ability. Especially, the solid Al-TiO2 with a Ti/Al ratio of 1 : 0.05 is more suitable for the separation of danshensu, exhibiting a higher adsorption (77.70%) under 2 h adsorption time and pH = 3; meanwhile, the high desorption rate (70.29%)was received under 80% ethanol and the sample concentration of 3.0 mg/mL.


2013 ◽  
Vol 850-851 ◽  
pp. 1267-1270
Author(s):  
Hong Li Teng ◽  
Li Cheng Guo ◽  
Shi Lin Chen

To study content of quercetin in Zhuang folk medicine Berchemia lineata in the different harvest times and to explore the laws of dynamic changes of quercetin content. Methods: determine 10 batches of Berchemia lineata in the HPLC-DAD method. Chromatographic conditions: Agilent XDB C18(150 mm×4.6 mm, 5 μm), the column temperature of 25 °C; mobile phase of methanol (A) - acetonitrile (B) -0.05% phosphoric acid solution (C), gradient elution; volume flow of 1 mL/min, detection wavelength of 254 nm. Result: sample injection volume of quercetin in the range of 0.69 μg ~ 4.83 μg has a good linear relationship with peak area, the average recovery is 99.8%, RSD: 1.27% (n = 6). From the overall analysis, content of quercetin in Berchemia lineata harvested in January is higher than that in other months. Conclusion: January should be the best month for harvest of Berchemia lineata.


2013 ◽  
Vol 844 ◽  
pp. 417-420
Author(s):  
Chalao Thepchalerm ◽  
Suwaluk Wisunthorn ◽  
Laurent Vaysse ◽  
Suda Kiatkamjornwong ◽  
Charoen Nakason ◽  
...  

Fresh field latex (FL) of Hevea brasiliensis was centrifuged to separate the major compartments: (i) the cream, (ii) the skim plus the C-serum, and (iii) the bottom fraction. Cream was dispersed in distilled water to prepare cream washed latex or CL sample. Skim was collected together with C-serum to prepare the skim latex or SKL sample. Then, films were made from FL, CL and SKL. The mesostructure (macromolecular structure and aggregates or gel) of the natural rubber films was studied by size exclusion chromatography coupled to a multiangular light scattering detector (SEC-MALS). The mesostructure was analyzed on fresh films and on films stored in the laboratory for three months (slow structuring). This study showed that FL and CL films had bimodal elution profiles of long and short polyisoprene chains as revealed by the two peaks on the chromatograms at low and high elution volumes, respectively. On the contrary, SKL films exhibited unimodal elution profiles at low elution volume and a highly abnormal molar masses elution profiles. After 3 months storage, the mesostructure of FL evolved dramatically especially the number-average molar masses (Mn), which increased by 60%. The mesostructure of CL films evolved at a lesser extent and, the mesostructure of SKL films exhibited no significant change. These results indicated (i) the skim rubber particles are not prone to slow structuring during storage in presence of serum and (ii) some constituents either in the serum or/and in the bottom fraction could still be present with cream and be involved in the slow structuring of cream particles latex.


2012 ◽  
Vol 599 ◽  
pp. 96-99
Author(s):  
Yan Min Hou ◽  
Xiao Jun Zhao ◽  
Ji Min Xie

nanometer attapulgite is a fine adsorptive reagent to Ni(II) in specific pH,adsorbent dosage , surging and depositing time, hydrochloric acid concentration, elution volume , surging and depositing time for the recovery and static adsorptive capability. The experimental results show that Zn(II)、Co(II)、K+、Cu(II)、Na+、Mn(II)、Pb(II)、Hg(II) 、SiO32- 、WO42- 、MoO42- 、HPO42-、VO3- didn’t interfere the adsorption to Ni(Ⅱ). the linear range is 0.10~1.5ug/mL, the regression equation is A=0.0476C+0.0084 r=0.9996 .the detection limit is 0.190μg/mL for Ni(II),recovery is 86.7.5%-102.5%. This method can be used to the determination of Ni(II) in environmental water.


2002 ◽  
Vol 17 (2) ◽  
pp. 163-170 ◽  
Author(s):  
Claude R. Mallet ◽  
Ziling Lu ◽  
Ray Fisk ◽  
Jeffrey R. Mazzeo ◽  
Uwe D. Neue

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