• Bulletin of the Korean Chemical Society
• /
• v.32 no.8
• /
• pp.2637-2642
• /
• 2011

A new ultrasonic-assisted micellar extraction and cloud-point pre-concentration method was developed for the determination of major saikosaponins, namely saikosaponins -A, -C and -D, in Radix Bupleuri by high performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD). The non-ionic surfactant Genapol X-080 (oligoethylene glycol monoalkyl ether) was chosen as the extraction additive and parameters affecting the extraction efficiency were optimized. The highest yield was obtained with 10% (w/v) Genapol X-080, a liquid/solid ratio of 200:1 (mL/g) and ultrasonic-assisted extraction for 40 min. In addition, the optimum cloud-point pre-concentration was reached with 10% sodium sulfate and equilibration at $60^{\circ}C$ for 30 min. Separation was achieved on an Ascentis Express C18 column (100 ${\times}$ 4.6 mm i.d., 2.7 ${\mu}M$) using a binary mobile phase composed of 0.1% acetic acid and acetonitrile. Saikosaponins were detected by ELSD, which was operated at a $50^{\circ}C$ drift tube temperature and 3.0 bar nebulizer gas ($N_2$) pressure. The water-based solvent modified with Genapol X-080 showed better extraction efficiency compared to that of the conventional solvent methanol. Recovery of saikosaponins ranged from 93.1 to 101.9%. An environmentally-friendly extraction method was successfully applied to extract and enrich major saikosaponins in Radix Bupleuri.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.51-55
• /
• 2007

The fractions of Ulva lactuca were studied to verify the antioxidant activities. The fractions from the ethanol extract of U. lactuca were prepared by the systematic extraction procedure with the solvents such as hexane, ethyl ether, ethyl acetate, butanol and $H_2O$. Furthermore, ethyl ether, ethyl acetate and aqueous fractions of U. lactuca were purified using HPLC. The antioxidant activities of purified samples from ethyl ether, ethyl acetate, and aqueous fractions were investigated using 1,1-diphenyl-2-picryl-hydrazil (DPPH). L-ascorbic acid, a positive control showed the highest DPPH radical scavenging activity. In addition, purified sample from aqueous fraction also showed relatively high activity. Purified sample from ethyl acetate fraction showed moderate activity, but purified sample from ethyl ether fraction showed the lowest activity. Dose dependent patterns were observed on all three samples tested. The lipid peroxidation inhibition activities of these three purified samples were also investigated. Purified sample from ethyl ether fraction of U. lactuca showed the highest activity and as strong activity as that of $\alpha-tocopherol$, a positive control. These results suggest that U. lactuca may be a useful candidate for a natural antioxidant agent.

• Korean Journal of Food Science and Technology
• /
• v.42 no.3
• /
• pp.257-262
• /
• 2010

Patulin, a secondary metabolite of mold, is commonly found in rotten apples. Many countries regulate patulin at levels ranging from 30 to $50\;{\mu}g/L$. Most analytical methods for removing patulin from apple juice include liquid-liquid extraction (LLE), which is time and labor intensive. To replace the LLE method, a solid-phase extraction (SPE) method has been developed for apple juice and unfiltered apple juice. A portion of the test sample was applied to a macroporous copolymer cartridge and washed with 5 mL of 1% sodium bicarbonate, followed by 5 mL of 1% acetic acid. Patulin was eluted with 5 mL of 2% acetonitrile in anhydrous ethyl ether. The mobile phase was tetrahydrofuran in water (0.8:99.2) and was detected with a UV detector at 276 nm. Recoveries ranged from 95 to 101% in test samples, and the minimum detectable level was 30 ppb. Because this SPE method is fast, easy, reliable, and inexpensive, it could be applicable for companies or analytical agencies to analyze patulin concentrations in apple juice.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.27 no.5
• /
• pp.462-468
• /
• 1994

Extraction yields of Hizikia fusiforme with four kinds of solvents and $0{\sim}90\%$ ethanol solutions, and antimicrobial activities of the extracts against Escherichia coli, Bacillus subtilis, Saccharomyces cerevisiae and Alternaria sp. were investigated. Determination of extraction yield with several solvents showed the highest value, $33\%$ (wt/wt), when distilled water was used. However, the extraction yields by hexane, ethyl ether and ethanol were less than $1\%$ (wt/wt). When dried Hizikia fusiforme was extracted at various concentrations of ethanol, 0 to $50\%$ solution gave similar yields and the extraction yields decreased rapidly as the ethanol concentrations increased above $70\%$, Ethanol-extract demonstrated antimicrobial activities against E. coli and B. subtilis, and ethyl ether- and hexane-extracts against E. coli. 70 and $90\%$ ethanol-extracts had potent antimicrobial activities against E. coli, and B. subtilis.

• Korean Journal of Food Science and Technology
• /
• v.34 no.5
• /
• pp.931-934
• /
• 2002

To establish the optimal conditions for increasing oil yields from grape seed, extraction solvent, extraction time, and temperature were examined. Using grinding, grinding and roasting, grinding and steaming, and grinding, roasting, and steaming methods. Pressing extraction method resulted in 34.0% oil yield. Grinding and roasting, grinding and steaming, and grinding, roasting, and steaming gave 64.3, 63.0, and 65.6% yield, respectively. Ether solvent treatment resulted in 77.4 and 80.9% recoveries after 24 and 48 h static, respectively. The results of sensory evaluation revealed, oils extracted under optimal condition showed the best flavor, aroma, and whor, followed by grinding, grinding and roasting, grinding, roasting, and steaming, and grinding and steaming. Taking these results together, the optimal methods for oils extraction from grape seed were as follows: grape seed ${\rightarrow}$ washing ${\rightarrow}$ drying ${\rightarrow}$ roasting ($95{\sim}100^{\circ}C$ for 20 min) ${\rightarrow}$ cooling (room temperature) grinding ${\rightarrow}$ (0.5 mm>) ${\rightarrow}$ steaming ($0.8{\sim}0.9\;kg{\cdot}f/cm^2$ for 10 min) ${\rightarrow}$ pressing ($1st\;400\;kg/cm^2\;for\;2{\sim}3\;min,\;2^{nd}\;550{\sim}600\;/cm^2$ for 10 min, $3^{rd}\;700kg/cm^2$ for 60 min) ${\rightarrow}$ oils (yield $;85{\sim}90%$).

• Bulletin of the Korean Chemical Society
• /
• v.23 no.1
• /
• pp.137-139
• /
• 2002

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.s01
• /
• pp.26-32
• /
• 1989

The analytic principles of GC and MS were explained in relation to plant hormone analyses and the characteristics of two instruments were compared. The selection of column, condition of measurement and the method of ionization to get a good spectrum were also briefly described. Finally, the pre-treatment of sample by solvent extraction method to remove the unnecessary part of sample and the synthetic method, especially reagents and reaction condition, for the preparation of ether or ester derivative which can be easily vaporized in GC were explained.

• Journal of Nutrition and Health
• /
• v.28 no.11
• /
• pp.1073-1077
• /
• 1995

The volatile components of Eutrema wasabi were prepared by distillation and ether extraction. The extracts were similar in the color, the odor, and the antimicrobial activity to allylisothiocyanate, the main ingredient of wasabi essential oil. The antimicdrobial activity of the extracts was evaluated and it was found that these had the antibacterial effect against a broad spectrum of pathogenic bacterial such as Staphylococcus, Escherichia, Pseudomonas and Salmonella.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.310.1-310.1
• /
• 2003

SD-2007 ia an apicidin analogue, possessing a potent histone deacetylase inhibiting activity. A rapid and senstive LC/MS method was developed for the determination of SD-2007 and its major active metabolite. apicidin. in rat serum. SD-2007 and apicidin was extracted by liquid-liquid extraction using methyl t-butyl ether. SD-2007 and apicidin were monitored in a SIM mode at m/z of 679 and 622, respectively. (omitted)

• Membrane and Water Treatment
• /
• v.6 no.2
• /
• pp.95-102
• /
• 2015

The presented research is about characterization of Cellulose Triacetate (CTA) based Polymer Inclusion Membranes (PIMs) which incorporated the commercial extractant Aliquat 336, Tributylphosphate (TBP) as modifier and 2-Nitro Phenyl Pentyl Ether (NPPE) as plasticizer, for the preparation of the membranes. Chemical and physical characteristics of the synthesized membranes especially membrane thickness and side difference effects were investigated. Different surface structures and membrane thickness affect the extraction efficiency of membranes. Membrane extraction experiments were studied where the glass-facing surface of the membranes placed next to feed phase and the air-facing surface to stripping phase. The membrane was characterized by means of AFM, FT-IR and SEM.