Organic solvent nanofiltration membrane cascades for solvent exchange and purification

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Organic solvent nanofiltration membrane cascades for solvent exchange and purification

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Purification of lignans from Schisandra chinensis fruit by using column fractionation and supercritical antisolvent precipitation

This study examined the use of ultrasonic-assisted extraction (UAE) coupled with column chromatography (CC) and supercritical antisolvent (SAS) precipitation in purifying five lignans from the dried fruit of Schisandra chinensis. Column fractionation of the ultrasonic extracts and SAS precipitation of the column elution resulted in a ten- and three-fold increase of the five lignans, respectively. Experimental data showed that the concentrations of the five lignans increased from 26.14 mg g−1 in the extraction to 581.85 mg g−1 in the effluent after SAS precipitation with a recovery of 84%. The effluent contained 145.32 mg g−1of schisandrol B, 56.65 mg g−1of schisandrin A, 66.38 mg g−1 of γ-schisandrin, 266.70 mg g−1 of gomisin N, and 46.80 mg g−1of schisandrin C. In addition, our experimental results from a response surface method designed SAS precipitations for the enhancement of the purity of the five lignans, showed that time and carbon dioxide flow rate are significant in altering the purity and the recovery. This work demonstrated that the five lignans of Schisandra chinensis were successfully purified by using the SAS process

Countercurrent flow of supercritical anti-solvent in the production of pure xanthophylls from Nannochloropsis oculata

This study examined pilot scaled elution chromatography coupled with supercritical anti-solvent precipitation (using countercurrent flow) in generating zeaxanthin-rich particulates from a micro-algal species. Ultrasonic agitated acetone extract subjected to column fractionation successfully yielded a fraction containing 349.4 mg/g of zeaxanthin with a recovery of 85%. Subsequently, supercritical anti-solvent (SAS) precipitation of the column fraction at 150 bar and 343 K produced submicron-sized particulates with a concentration of 845.5 mg/g of zeaxanthin with a recovery of 90%. Experimental results from a twofactor response surface method SAS precipitation indicated that purity, mean size and morphology of the precipitates were significantly affected by the flow type configuration, feed flow rate and injection time

Low density supercritical fluids precipitation of 9-cis and all trans-β-carotenes enriched particulates from Dunaliella salina

In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-β-carotenes from Dunaliella salina. Total concentration of 9-cis (134.7 mg/g) and trans-β-carotene (204.2 mg/g) was increased from 338.9 mg/g of the ultrasonic extract to 859.7 mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1 mg/g (355.6 for 9-cis and 576.5 for trans) of total β-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total β-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-β-carotenes by low-density SAS was proved to be feasible and environmental benign

Low density supercritical fluids precipitation of 9-cis and all trans-β-carotenes enriched particulates from Dunaliella salina

In this study, supercritical anti-solvent (SAS) pulverization coupled with reverse phase elution chromatography was employed to isolate 9-cis and trans-β-carotenes from Dunaliella salina. Total concentration of 9-cis (134.7 mg/g) and trans-β-carotene (204.2 mg/g) was increased from 338.9 mg/g of the ultrasonic extract to 859.7 mg/g (338.9 for 9-cis and 520.8 for trans) of the elution fraction. The SAS pulverization of the collected fraction further produced submicron-sized particulates containing 932.1 mg/g (355.6 for 9-cis and 576.5 for trans) of total β-carotenes with a recovery of 86.3% (83.9% for cis and 87.8% for trans). Effects of two SAS operational conditions on the purity, recovery of total β-carotenes, mean size and morphology of the precipitates were obtained from an experimentally designed method. Generation of micronized particulates enriched with 9-cis and trans-β-carotenes by low-density SAS was proved to be feasible and environmental benign

Abstracts of 2nd International Symposium on Plastic Pollution

This book presents the abstracts of the selected contributions to the Second International Symposium on Plastic Pollution, hosted from 3rd to 4th of November 2022 in hybrid mode by the “Plastic Free” Specialized Graduate School, University of Seoul. The symposium covers “Challenges and Possible Solutions of Plastic Pollution” and “Toxicity Assessment of Plastics”. The symposium was special as it brought together researchers from multidisciplinary fields, bringing new research ideas and creating collaboration in the field of plastic pollution. With 20 experts from 7 countries and two special sessions with different themes, the symposium offered a perfect platform for attendees to share their research ideas. Symposium Title: 2nd International Symposium on Plastic PollutionTheme: SYM-1~2: Challenges and Possible Solutions of Plastic Pollution. SYM-3: Toxicity Assessment of PlasticsSymposium Date: 3-4 November 2022Symposium Location: Hybrid (online and offline – Jeju-Island Pacific, South Korea)Symposium Organizer: Plastic-Free Specialized Graduate School, University of Seoul, South KoreaSymposium Sponsors: Ministry of Environment & KEITI, South Korea Previous Year Abstract Book: Abstracts of 1st International Symposium on Plastic Pollutio

Empagliflozin in Patients with Chronic Kidney Disease

Background The effects of empagliflozin in patients with chronic kidney disease who are at risk for disease progression are not well understood. The EMPA-KIDNEY trial was designed to assess the effects of treatment with empagliflozin in a broad range of such patients. Methods We enrolled patients with chronic kidney disease who had an estimated glomerular filtration rate (eGFR) of at least 20 but less than 45 ml per minute per 1.73 m(2) of body-surface area, or who had an eGFR of at least 45 but less than 90 ml per minute per 1.73 m(2) with a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 200. Patients were randomly assigned to receive empagliflozin (10 mg once daily) or matching placebo. The primary outcome was a composite of progression of kidney disease (defined as end-stage kidney disease, a sustained decrease in eGFR to < 10 ml per minute per 1.73 m(2), a sustained decrease in eGFR of & GE;40% from baseline, or death from renal causes) or death from cardiovascular causes. Results A total of 6609 patients underwent randomization. During a median of 2.0 years of follow-up, progression of kidney disease or death from cardiovascular causes occurred in 432 of 3304 patients (13.1%) in the empagliflozin group and in 558 of 3305 patients (16.9%) in the placebo group (hazard ratio, 0.72; 95% confidence interval [CI], 0.64 to 0.82; P < 0.001). Results were consistent among patients with or without diabetes and across subgroups defined according to eGFR ranges. The rate of hospitalization from any cause was lower in the empagliflozin group than in the placebo group (hazard ratio, 0.86; 95% CI, 0.78 to 0.95; P=0.003), but there were no significant between-group differences with respect to the composite outcome of hospitalization for heart failure or death from cardiovascular causes (which occurred in 4.0% in the empagliflozin group and 4.6% in the placebo group) or death from any cause (in 4.5% and 5.1%, respectively). The rates of serious adverse events were similar in the two groups. Conclusions Among a wide range of patients with chronic kidney disease who were at risk for disease progression, empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes than placebo