• Journal of Pharmaceutical Investigation
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• v.34 no.1
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• pp.29-34
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• 2004

The solubility and stability of quercetin in various vehicles were determined. The solubility of quercetin at $28^{\circ}C$ increased in the rank order of isopropyl myristate < oleyl alcohol < propylene glycol monolaurate < oleoyl macrogol­6 glycerides < linoleoyl macrogol-6 glycerides < propylene glycol laurate (PGL) < propylene glycol monocaprylate (PGMC) < polyethylene glycol-8 glyceryl linoleate < caprylocaproyl macrogol-6 glycerides < diethylene glycol mono ethyl ether (DGME). The addition of DGME to non-aqueous vehicles such as PGL ad PGMC markedly increased the solubility of quercetin. From the stability studies, it was found that quercetin was unstable due to rapid oxidation by dissoved oxygen. The addition of a combination of ascorbic acid and edetic acid (EDTA) at 0.1 % markedly decreased the degradation rates of quercetin in 40% polyethylene glycol 400 in saline. Quercetin was relatively unstable in non-aqueous vehicles such as PGL and PGMC alone, and PGL-PGMC co-solvent The degradation of quercetin in such non-aqueous vehicles was fast, depending on temperature. The addition of butylated, hydroxytoluene, butylated hydroxyanisole, citric acid and/or EDTA at 0.1 % was effective in retarding the degradation of quercetin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.1024-1029
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• 2010

Opuntia ficus-indica and Aloe vera slices were dried using 20, 30, and 40% polyethylene glycol (PEG) 4,000 as a dehydration agent, and the dried samples were compared with the hot-air dried and freeze dried in terms of rehydration ratio, color, and sensory evaluation. The moisture content of the PEG-treated samples decreased with increasing concentrations of polyethylene glycol. The rehydration ratio of the PEG-treated samples was better than those of the hot air-dried or freeze-dried samples. The color of the PEG-treated samples was similar to that of the freeze-dried samples and better than that of the hot air-dried samples. The sensory evaluation of PEG-treated samples was better than those of the hot air-dried or freeze-dried samples. These results suggest that dehydration of Opuntia ficus-indica and Aloe vera slices using PEG is very effective in terms of rehydration ratio and minimal damage of cell structure.

• Clean Technology
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• v.21 no.2
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• pp.124-129
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• 2015

The constant-volume method was used to determine the solubility of CO₂ in various physical absorbents such as DMPEG (dimethyl ether of polyethylene glycol), DEC (diethyl carbonate), DMC (dimethyl carbonate), and TAT (triacetin) in the total pressure range from 5 to 30 bar. The Peng-Robinson equation of state has been used to describe the equilibrium behavior of these mixtures. It was found that the solubility of absorbents was in the of DMPEG250 > TAT > DEC > DMC at the same temperature. Futhermore, the solubiity of blended absorbent of DMPEG250 and DEC is higher than that of DMPEG 250 alone. Therefore, blended absorbent of DMPEG250 and DEC is expected to be an effective and low cost absorbent for physical absorption in precombustion CO₂ capture.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.485-489
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• 2017

Polyethylene terephthalate (PET) has been widely applied in polymers and packaging industries to produce synthetic fibers, films, drink bottles or food containers. Therefore, it has become one of the major plastic wastes. In this article, glycolysis known as one of the main methods in PET chemical recycling was investigated using a glycol to break down the polymer into a monomer. Glycolysis of PET and ethylene glycol was performed in a micro-tubing reactor under various conditions. The effect of glycolysis conditions on the product distribution was investigated at experimental conditions of the EG/PET ratio of 1~4, the reaction time of 15~90 min and the reaction temperature of $250{\sim}325^{\circ}C$ with Mn and Cu catalysts. The highest yield of bis (2-hydroxyethyl) terephthalate monomer (BHET) was obtained as 89.46 wt% under the condition of the reaction temperature of $300^{\circ}C$ and the time of 30 min using 10 wt% $Cu/{\gamma}-Al_2O_3$ catalyst, with the PET and ethylene glycol ratio of 1 : 2.

• Korean Journal of Medicinal Crop Science
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• v.26 no.1
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• pp.55-63
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• 2018

Background: The present study assessed the response of kenaf (Hibiscus cannabinus L., Jangdae) seed to NaCl and the effects of polyethylene glycol (PEG) on kenaf seed germination and vigor. Methods and Results: Seed germination ranged from 11.3% to 58.8% after 24 hours of immersion in NaCl concentrations from 0% to 0.5%. The priming treatments had lower electrical conductivity (EC) values for the seeds than for the control and a deteriorated palisade layer. Priming in 10% PEG for 48 hours increased the germination upto 96.3% in $H_2O$ solution and 98.8% in 0.3% NaCl solution compared to that of the control (78.8%). Germination synchronization, and shoot and root growth of the primed seeds were greater than those of the control. The $T_{50}$ of the control in $H_2O$ and 0.3% NaCl solution was 22 and 28 times, respectively. After priming, nine times was sufficient to reach $T_{50}$ in both solution. The mean number of days to germination (MDG) decreased from 1.43 days for the control to 0.55 days for 0% PEG in $H_2O$ solution and from 1.57 days for the control to 0.56 days for 0% PEG in 0.3% NaCl solution. The dry weight after the 10% PEG treatment was higher than that of the control. Conclusions: Taken together, 10% PEG treatment for 24 hours is recommended for kenaf seed invigoration before planting.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.77-83
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• 1990

Factors influencing the fusion frequency of protoplasts were investigated with auxotrophic mutants of Pleurotus florida and Pleurotus ostreatus. Immediately after the polyethylene glycol (PEG) solution was added, the protoplasts adhered firmly and shrank. During the subsequent dilution with 0.6 M sucrose, the protoplasts regained their normal size and larger bodies were observed. Interspecific heterokaryons were obtained by fusion of the nutritionally complementing protoplasts. Hyphae of the heterokaryotic fusants formed true clamp connections. The optimum conditions were a total of 1 to 15 million protoplasts per ml, 30% polyethylene glycol 8000 solution with adjustment to pH 8.0 and 0.6 M sucrose stabilized regeneration medium. Other parameters such as $CA^{++}$, glycine, exposure time and temperature influenced mainly the viability of the protoplasts.

• Korean Journal of Clinical Pharmacy
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• v.22 no.3
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• pp.202-210
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• 2012

Methoxy polyethylene glycol-epoetin beta (MPG-EPO), a continuous erythropoietin receptor activator, is a new erythropoiesis-stimulating agent with a long half-life. The purpose of this prospective study is to assess the effects of once-monthly subcutaneous MPG-EPO on hematological responses and nutritional status in peritoneal dialysis patients. Forty four patients undergoing stable peritoneal dialysis were enrolled into the study. Darbepoetin alfa therapy, in peritoneal dialysis patients, was converted to the monthly administration of subcutaneous MPG-EPO for 6 months. The starting dose of MPG-EPO was based on the previous weekly dose of darbepoetin alfa. The dose adjustments were performed to maintain the hemoglobin (Hb) levels in a target range of 10.5-11.0 g/dL. If the Hb levels exceeded 11.0 g/dL, MPG-EPO was temporarily interrupted for 1 month. The mean Hb levels were stable with the values of $9.5{\pm}1.1$ g/dL at baseline, and $10.4{\pm}0.9$ g/dL at the 6th month after conversion. The mean differences in the changes of Hb levels between the baseline and the 6th month were $0.9{\pm}1.4$ g/dL, which was statistically significant. However, the mean differences of iron, transferrin saturation and ferritin concentrations were not significant. It did not show significant differences in the changes of the nutritional parameters. These results suggest that the once-monthly subcutaneous administration of MPG-EPO for 6 months effectively maintains the Hb levels and nutritional status in peritoneal dialysis patients. Taken together, the once-monthly subcutaneous administration of MPG-EPO was practical and might improve the clinical compliance for the management of renal anemia in peritoneal dialysis patients.

• Journal of Yeungnam Medical Science
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• v.32 no.1
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• pp.55-59
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• 2015

The widely used polyethylene glycol (PEG)-based solutions have been proven effective for bowel preparation when 4 L of the solution is administered before colonoscopy. However, large volumes of the solutions are generally poorly tolerated. A new PEG-based solution consisting of 2 L of PEG and a high dose of ascorbic acid has recently become available. Electrolyte abnormalities caused by PEG-based solutions have rarely been reported. We report on a case of acute severe hyponatremia with associated generalized tonic-clonic seizures after bowel preparation with a low-volume PEG plus ascorbic acid solution in a 74-year-old woman with no history of seizures. She took a beta blocker, an angiotensin-converting enzyme inhibitor, and glimepiride for hypertension and diabetes mellitus. She showed general weakness, nausea, agitation, muscle cramping, and seizures after ingestion of the PEG plus ascorbic acid solution. Her serum sodium level was 112 mEq/L. Her symptoms improved after intravenous administration of hypertonic saline. Physicians should pay attention to screening for electrolytes and development of neurological symptoms during bowel preparation.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.219-228
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• 2018

This study evaluated the effects of glycerol polyethylene glycol ricinoleate (GPGR) supplementation in different energy density diets on the growth performance, blood profiles, excreta gas emission, and total tract apparent retention (TTAR) of nutrients in broilers. A total of 544 one-day-old male Ross broilers were used in a 35-day trial. The broilers were allocated into one of four treatment groups in a $2{\times}2$ factorial arrangement with two levels of energy densities (a normal energy or decreased energy density) and GPGR (0 and 0.035%). From day 18 to 35, the GPGR supplemented and normal energy density diet groups showed a significantly improved (p < 0.05) body weight gain (BWG). Meanwhile, the GPGR supplemented diet group had a significantly reduced (p < 0.05) feed conversion ratio (FCR) compared to that of the non-supplemented diet group. From day 0 to 35, the GPGR supplemented diet and the normal energy density diet groups had a significantly increased (p < 0.01) BWG and a reduced (p < 0.01) FCR. Moreover, GPGR supplementation tended to increase (p < 0.1) the TTAR of the dry matter (DM) compared with the non-supplemented diets. Likewise, the normal energy density diets had a significantly improved TTAR for the gross energy (GE) (p < 0.05) than that of the decreased energy density diets. No interactive effects were observed between the energy density and GPGR supplemented diets. In conclusion, both dietary GPGR supplementation and normal energy density diets had beneficial effects on the growth performance of broiler chickens without any adverse effects on blood profiles and excreta gas emission.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.329-334
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• 1986

The bacteria capable of utilizing polyethylene glycol(PEG) 6,000 as a sole carbon source were isolated from soil and sewage water connected to factory area. The isolate designated as EL-033 had high biodegradability on PEG 6,000, and was identified as Micrococcus sp. Micrococcus sp. EL-033 could grow on and degrade di-, tri-, tetraethylene glycols and PEGs with molecular weight up to 6,000 and very slowly stilize PEG 20,000 as sole carbon source, but not degrade ethylene glycol. The growth rate of isolate was increased in the higher molecular weight PEGs. The optical culture medium was established to be as follow: PEG 6,000, 0.2%(w/v); $K_2HPO_4$, 0.1%; $NaH_2PO_4{\cdot}12H_2O,\;0.1%\;:\;MgSO_4{\cdot}7H_2O$, 0.05%; polypeptone, 0.1% in distilled water, pH7.5. About 90% of PEG 6,000 was degraded in exponential phase of 48h culture and PEG 6,000 was completely degraded during 72h.