• Korean Journal of Medicinal Crop Science
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• v.15 no.4
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• pp.266-270
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• 2007

This research was conducted to investigate antioxidant activities of Juglans mandshrica forages by the irradiation of far infrared ray during leaf drying processes before compound extraction, with its potential use for activating antioxidants. The contents of total phenolics and flavonoids in the basis of a gram leaf dry weight were maximized in 20 min at 30 V of far infrared irradiation. Total phenolic content was 25.43 mg/g in the FIR treatment, while it was 21.12 mg/g in the non-FIR treatment control. Total flavonoid content was 39.38 mg/g in the FIR treatment, while it was 32.78 mg/g in the non-FIR treatment control. The contents were decreased when the condition of far infrared ray irradiation was higher voltage and longer treatment time, exhibiting 16.93 mg/g of total phenolics and 23.78 mg/g of total flavonoids in 30 min at 50 V of far infrared irradiation. The antioxidant activities were shown to positive relationships with the contents of total phenolics and total flavonoids. In this study, we concluded that content of bioactive molecules relating antioxidant activity in Juglans mandshrica forages is optimized in 20 min at 30 V of far infrared irradiation for leaf drying process.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.98-104
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• 2011

We investigated inhibitory effects of ginseng extracts against compound 48/80-induced responses in rat peritoneal mast cells. Initially, we optimized extraction condition with various temperature and time for recovery of high saponin contents in extracts. Using a primary rat peritoneal mast cells, we examined whether ginseng extracts inhibit compound 48/80-induced histamine release form rat mast cells. High red ginseng-spercific saponin containing extracts were recovered at $85^{\circ}C$ for 48 hr, and had no cytotoxicity with relatively high dose of extracts on rat peritoneal mast cells(<0.5 mg/ml). For examine of ameliorate effects of mast cells responses by ginseng extract, we pre-treated the extracts or saline to mast cells and treated compound 48/80. In results, compound 48/80 treatment was increased histamine release (approximately 30%) from mast cells than normal group, whereas ginseng treatment was completely inhibited histamine release. These results suggested that ginseng extracts inhibits the compound 48/80-induced mast cell activation, and ginseng extracts is a candidate for effective therapeutic tools of allergic diseases.

• Food Science of Animal Resources
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• v.31 no.6
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• pp.944-951
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• 2011

An improved cholesterol analysis method was developed for powdered infant formula by gas chromatographic separation after liquid-liquid extraction and partition. In the official Korea Food Standard method for cholesterol analysis, the water phase and solvent phase were not well separated in the case of emulsified foods such as powdered infant formulas and baby foods. For the rapid and simple sample preparation method, an optimized direct saponification condition was established for heating temperature, heating time, and KOH concentration. From the results, the optimum conditions were as follows: heating temperature $90^{\circ}C$, heating time 60 min, and 16 M KOH 10 mL for a 2 g infant formula sample; improved separation condition for gas chromatography was as follows: the initial oven condition was $250^{\circ}C$ for 25 min, the oven temperature was increased to $290^{\circ}C$ by $10^{\circ}C$/min ratio, and finally the oven temperature remained at $290^{\circ}C$for 9 min. The developed method could be implemented for the study of cholesterol, providing the advantages of reduced inspection time and cost in emulsified foods such as infant formula.

• Journal of Life Science
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• v.27 no.7
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• pp.754-759
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• 2017

The 100 l culture system was made on the basis of LED light, and Nannochloropsis oculata was cultured in f/2 medium at light intensity ($100{\mu}mol/m^2/s$), culture temperature ($20^{\circ}C{\pm}1^{\circ}C$) and LD cycle (12hr). As a result, the maximum biomass of 1.07 g/l was cultured as a result of 100 l mass culture at $100{\mu}mol/m^2/s$ and 24 mg/l nitrate concentration in LED blue (475 nm). The extraction was carried out using sonicator, homogenizer and chemical method 0.5M HCl shredding method. The contents of chlorophyll a, chlorophyll b and carotenoid were 1.6, 0.5 and 0.3 mg/g cell. When using homogenizer, it was measured at 1.0, 0.6 and 0.2 mg/g cell. The chemical breakdown method of 0.5M HCl, chlorophyll a, b, and carotenoid contents were measured as 0.9, 0.8, 0 mg/g cell. The highest amount of biomass during the distruption time was measured at 3.6 mg/g cell at 15 min disintegration and acetone, 3.6 mg/g cell of acetone, methanol, and ethanol were measured as effective solvents. Concentration was measured by using microfilter, disk type continuous centrifuge and tubular type continuous centrifuge were 16.0, 1.1 and 0.5 g/l, respectively. Four kinds of equipment such as hot air dryer, vacuum dryer, spray dryer and freeze dryer were tested to optimize the drying process. As a result, the recovery rates of spray dryer and freeze dryer were 80% and 60%.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.401-416
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• 2011

The recent trend for pesticide residue analysis in food involves fast cleanup and use of mass spectrometry to achieve quantitative and qualitative analysis at the same time. Recently, the QuEChERS (quick, easy, cheap, effective, rugged and safe) multi-reside method has received much attention as a fast extraction and cleanup method of pesticide residue analysis. Therefore, multi-residue analysis of 236 pesticides was tested with the QuEChERS method by concurrent use of PTV-GC/TOFMS (gas chromatography/ time-of-flight mass spectrometry with programmable temperature vaporizer). PTV condition was optimized and when the method was applied to apples, pesticide recovery rates (spiked at 400 ng/g) ranged from 80% to 120%, and RSD values were under 10% for most compounds. The results showed that the QuEChERS sample preparation and PTV-GC/TOFMS analysis can be applied to multi-residue analysis of pesticides in fruits and vegetables.