• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.242-256
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• 2012

QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method has been a lot of research for pesticide analysis, because it is very simple and fast. However, this method requires high sensitivity instrument such as LC-MS/MS because of the use of small sample volume and many impurities compared to the conventional method. So, QuEChERS method needs to be modified for using with HPLC and GC-ECD/NPD. The aim of this work was to study the application of the QuEChERS method as well as its modification for the extraction and preconcentration of 5 groups of 61 pesticides from 4 fruits prior to their determination by HPLC-PDA, GC-ECD/NPD, and LC-MS/MS. The method was validated using spiking levels at 0.1 mg/kg (or 0.01 mg/kg) in apple, grapes, pear and persimmon. The average recovery by QuEChERS AOAC Official 2007. 01 version using the LC-MS/MS varied from 71.1127.4% for 61 pesticides. The average recovery rates using modified QuEChERS varied from 70.9~126% for 61 pesticides by HPLC-PDA and GC-ECD/NPD. The results satisfied the criteria of multiple pesticide residue analysis, setting 70~130% for recovery rates and below 30% for CV.

• Food Science and Preservation
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• v.23 no.7
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• pp.931-938
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• 2016

To evaluate the effect of freezing temperature on quality characteristics of dried persimmons, dried persimmons were frozen at $-50^{\circ}C$ (quick frozen, QF) and $-20^{\circ}C$ (slow frozen, SF) for 24 hr. Frozen persimmons were then stored at -20, -10, 0 and $10^{\circ}C$ for 80 days. Total free sugar content of SF persimmons was higher than those of QF in the $+10^{\circ}C$ and $-20^{\circ}C$ stored samples. Except for samples stored at $10^{\circ}C$, the CIE $L^*$ values for QF persimmons were higher than those for SF persimmons. For samples stored at $10^{\circ}C$ and $0^{\circ}C$, the CIE $a^*$ and $b^*$ values of SF samples were higher than those for QF samples. The texture of frozen dried persimmons was investigated to determine springiness, chewiness and hardness. Chewiness and hardness of samples held at $0^{\circ}C$ were higher in SF than in QF persimmons. However, when stored at $-10^{\circ}C$, chewiness and hardness were higher in QF than in SF samples. Springiness results were similar among the QF and SF persimmons held at different storage temperatures. For all storage temperatures, QF persimmons had a high soluble tannin content. All of the sample, the average soluble tannin contents of QF is 236.09 mg%. On the other hands, those of SF is 226.87 mg%. The results indicate that freezing rate and holding temperatures have significant effects on dried persimmon texture, soluble tannin level, and free sugar content. Further studies that include sensory evaluations are needed to determine the optimum freezing rate and holding temperature for dried persimmons.

• Journal of Life Science
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• v.24 no.9
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• pp.935-945
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• 2014

Persimmon leaves were commonly consumed as beverages, but were also used as popular folk medicine in Asia. The purpose of this work was to assess the biological activities of Diospyros Lotus L. extracts (DLLE). Various solvent extracts, including n-Hexnae, $CHCl_3$, EtOAc, and n-BuOH fractions, were obtained from the methanol extract of Diospyros Lotus L. leaves. The increasing interest in the powerful biological activity of plant phenolics and flavonoids outlined the necessity for determining their content in medicinal herbs. In this study, the total polyphenol and flavonoid contents (TPC and TFC) in the EA fraction were higher than those of other fractions. The biological activities of DLLE were tested using the 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity assay, as well as superoxide dismutase (SOD) activity as an anti-oxidant effect and ${\alpha}$-glucosidase inhibitory activity as an anti-diabetic effect. The EA fraction with high TPC and TFC values showed the highest anti-oxidant effect and high ${\alpha}$-glucosidase inhibition. The EA fractions were further purified into eight fractions using open column chromatography. Higher anti-oxidant and anti-${\alpha}$-glucosidase activity were observed in polar fractions. The content of the flavonoids, including quercein-3-O-rutinoside, kaempferol-3-O-glucoside, myricetin, luteolin, and kaempferol, were analyzed in effective fractions using high-performance liquid chromatography (HPLC). The results suggest that DLLE have anti-oxidative and anti-diabetic effects and thus, have the potential as anti-diabetic materials and as a source for natural health products.

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.46-69
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• 2013

The results of study on the meaning landscape and environmental design techniques of the Byulup, Yoohoedang garden(Hageowon) based on the story in the collection of Kwon Yi-jin (Yoohoedangjip, 有懷堂集), are as below. First, Yoohoedang Kwon Yi-jin (有懷堂 權以鎭 : 1668~1734) constructed a Byulup garden consisting of ancestor grave, Byulup, garden, and a school, through 3 steps for 20 years in the back hill area of Moosoo-dong village, south of Mountain Bomun in Daejeon. In other words, he built the Byulup(別業, Yoohoedang) by placing his father's grave in the back hill of the village, and then constructed Yoegeongam(餘慶菴) and Geoupjae(居業齋) for protection of the pond(Napoji, 納汚池), garden(Banhwanwon, 盤桓園), and ancestor graves, and descendants' studying in the middle stage. He built an extension in Yoohoedang and finally completed the large-size garden (Hageowon) by extending the east area. Second, in terms of geomancy sense, Yoohoedang Byulup located in Moosoo-dong village area is the representative example including all space elements such as main living house (the head family house of Andong Kwon family), Byulup (Yoohoedang), ancestor graves, Hagoewon (garden) and Yoegeongam (cemetery management and school) which byulup type Byulseo should be equipped with. Thirdly, there are various meaning landscape elements combining the value system of Confucianism, Buddhism and Taoism value, including; (1) remembering parents, (2) harmonious family, (3) integrity, (4) virtue, (5) noble personality, (6) good luck, (7) hermit life, (8) family prosperity and learning development, (9) grace from ancestors, (10) fairyland, (11) guarding ancestor graves, and (12) living ever-young. Fourth, after he arranged ancestor graveyard in the back of the village, he used surrounding natural landscapes to construct Hagoewon garden with water garden consisting of 4 mountain streams and 3 ponds for 13 years, and finally completed a beautiful fairyland with 5 platforms, 3 bamboo forests, as well as the Seokgasan(石假山, artificial hill). Fifth, he adopted landscape plantation (28 kinds; pine, maple, royal azalea, azalea, persimmon tree, bamboo, willow, pomegranate tree, rose, chinensis, chaenomeles speciosa, Japanese azalea, peach tree, lotus, chrysanthemum, peony, and Paeonia suffruticosa, etc.) to apply romance from poetic affection, symbol and ideal from personification, as well as plantation plan considering seasonal landscapes. Landscape rocks were used by intact use of natural rocks, connecting with water elements, garden ornament method using Seokyeonji and flower steps, and mountain Seokga method showing the essence of landscape meanings. In addition, waterscape are characterized by active use of water considering natural streams and physio-graphic condition (eastern valley), ecological corridor role that rhythmically connects each space of the garden and waterways following routes, landscape meaning introduction connecting 'gaining knowledge by the study of things' values including Hwalsoodam(活水潭, pond), Mongjeong(蒙井, spring), Hosoo(濠水, stream), and Boksoo(?水, stream), and sensuous experience space construction with auditory and visualization using properties of landscape matters.