• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.52-64
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• 1990

As a search for natural antioxidants, antioxdative fractions in Pueraria roots were extracted, identified using column chromatography, thin layer chromatography or high performance liquid chromatography. The components which have most effective antioxidative activities were further identified by IR and GC-MS. Separated antioxidative components were then added to four different oils to examine their antioxidative activities. Yield of extract obtained from pueraria root powder by solvent extraction using four step solvent systems was 2.54%. Antioxidative activity of the extracts was as effective as that of 100 ppm ${\delta}$-tocopherol addition, when 0.1% of the extracts was added to linoleic acid. The strongest antioxidative component of methanol extract of pueraria root was identified as puerarin. Aunioxidative activity of puerarin on lard was more effective than ${\alpha}$-tocopherol, but less effective than ${\delta}$-tocopherol. When the puerarin was added to edible oil and heat treated at $145^{\circ}C$, the acid value was lowest in lard and was highest in soybean oil. Antioxidative activity in terms of carbonyl value, thiobarbituric acid value and anisidine value was most high in palm oil and least in soybean and cottonseed oil.

• Polymer(Korea)
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• v.25 no.5
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• pp.665-670
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• 2001

The solvent extraction of polyethylene glycol (PEG) by ethanol has been studied for the powder injection molded compacts of Sr-ferrite/PEG/carnauba wax/HDPE. The extraction rate of PEG is sensitively proportional to the solvent temperature whereas it is inversely proportional to the contents of PEG, the molecular weight of PEG. and the specimen thickness. The high extraction rate of PEG is achieved under the following conditions: solvent temperature of $70^{\circ}C$, PEG contents of 30%, and PEG molecular weight of 400 g/mol. In the early stage of solvent extraction, the non-linear relationship between the extraction rate and the square root of the extraction time indicates that the extraction of PEG does not follow the Fickian behavior. At extraction times longer than 180 min. however, the extraction of PEG follows the Fickian behavior. The extraction fate of PEG by ethanol is about$1.0{ imes}10^{-6}g/cm^2sec$ enough for common applications.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.160-169
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• 2022

In the present study we evaluated the efficacy of a bioformulation of Streptomyces cameroonensis for control of black pod disease in cocoa and enhancement of seedling growth. The formulation developed using talc powder and cassava starch as carriers showed high shelf-life of 1.07 × 10⁶ CFU/g after six months storage at 4℃. The formulation was tested for inhibition of spore germination in Phytophthora megakarya and showed 100% inhibition at 10% (w/v) of formulation. To determine the efficacy of the formulation, we performed an in planta assay in the greenhouse on two hybrids of cocoa seedlings, the tolerant SNK413 × (♂) T79/467 and the susceptible UPA 134× (♂) SCA 12. Detached leaf assay showed a significant reduction in the disease severity index of about 67% for the tolerant hybrid and 55% for the susceptible hybrid compared to non-treated plants. A significant enhancement in stem length, leaf surface area and root weight was observed. Analysis of biochemical markers of defense showed a significant increase in total polyphenol, flavonoid, and total protein contents. There was also significant upregulation of PR-proteins such as chitinases, peroxidases and β-1, 3-glucanases following treatment of both tolerant and susceptible hybrids, though with a higher level of synthesis in the tolerant hybrids. A significant increase was also observed in polyphenol oxidase activities in plants treated with the formulation. This work demonstrated the stability and effectiveness of the S. cameroonensis powder formulation in suppressing black pod disease in cocoa and subsequently enhancing the growth of seedlings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.262-270
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• 2012

This research was performed to find out the root characteristics of sweetpotato (Ipomoea batatas LAM.) cultivars according to the cultivation regions. Total 10 sweetpotato culivars, 6 yellow, 2 purple and 2 orange, were used for experiment. Samples were cultivated in Muan, Iksan, Nonsan, Boryeong and Hamyang. Precipitation and average temperature during the growth period of sweetpotato cultivation were 882~1,682 mm and 16.7~$28.2^{\circ}C$, respectively. Accumulated temperature was 3,122~$3,282^{\circ}C$. Soil texture was found of sandy loam in Muan, Iksan and Boryeong, sandy clay loam in Nonsan, and loam in Hamyang. The yield of root, dry matter content, starch value and soluble solids contents were high in Muan. The length/width ratio was high in Hamyang. The color values of sweetpotatoes were high in Nonsan. The protein content of sweetpotato powder was high in the Iksan, crude fat content and ash content were high in the Hamyang. The results of this study, we could see that root characteristics of sweetpotato in the same cultivars appeared differently depending on the cultivated regions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.496-501
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• 2009

This study was carried out to investigate physiological functionalities of tea prepared by various thermal processing methods from Ixeris dentata root in order to elevate utilization of Ixeris dentata root as food. These methods included natural drying (ND), hot-air drying (HAD, $75^{\circ}C$), hot-air drying after steam (HADS, steaming at $95^{\circ}C$ for 30 min) and roasting after hot-air drying (RHAD, roasting at $140^{\circ}C$ for $2{\sim}3$ min). Physiological functionalities of tea prepared by ND, HAD, HADS, and RHAD were measured as hot-water extracts and each tea was extracted by 100 mL water on 1 g dried Ixeris dentata root powder. Electron donating abilities were the highest in HADS treatment at 98%. SOD-like activities were the highest in RHAD at 35.61%. Both ACE and tyrosinase inhibitory activities were the highest on ND treatment at 52.34% and 44.60%, respectively. Nitrite scavenging abilities of all treatment were the highest at pH 1.2 and the highest activity among them was on RHAD treatment at 50.5%.

• Journal of Plant Biotechnology
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• v.48 no.2
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• pp.77-85
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• 2021

Hydroponic cultivation, in which crops are grown without soil and are unaffected by the weather, has many advantages over conventional soil cultivation. The crop's growth can be further accelerated by using nutrient solution in place of water. This study investigated the growth and physicochemical properties of hydroponic barley sprouts under various nutrient solution and artificial light treatments. The shoot, root, and total plant length increased over time, with the fastest growth occurring in the nutrient solution and light-emitting diode (LED) treatments. Fresh and dry plant weights were higher in the fluorescent lamp treatment than in the LED treatment. Barley sprout powder color differed slightly by treatment, with the Hunters L value ranging from 50.79 to 53.77; Hunters a value from -6.70 to -4.42; and Hunters b value from 13.35 to 14.76. The Hunters L and Hunters b values were highest in the LED treatment, whereas the Hunters a value was relatively highest in the fluorescent lamp treatment. The total phenol content was higher in the control than in the nutrient solution treatment; however, the total flavonoid content showed the opposite pattern to that of total phenol content, being highest in plants that were grown in nutrient solution. The Trolox equivalent antioxidant capacity (TEAC) was higher in the control group than in the nutrient solution group. The ferric ion reducing antioxidant power (FRAP) was higher in the fluorescent treatment group than in the LED treatment group. The total amino acid composition ranged from 106.82 to 122.63 mg/g dry powder, with the essential amino acid composition ranging from 47.01 to 56.19 mg/g, and non-essential amino acid composition from 67.86 to 77.66 mg/g. The most frequently detected compositional amino acid was aspartic acid, followed by glutamic acid, alanine, leucine, and valine.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.157-164
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• 2014

Objective of this research was to develop root media containing expanded rice hull (ERH) and carbonized rice hull (CRH). To achieve this, the physico chemical properties of two materials were analysed and blended with peatmoss (PM) or coir dust (CD) with various ratio. Based on the physical properties of the blended materials, 4 root media were selected for future experiment. After the analysis of pH and EC of the selected root media, the kinds and amount of pre-planting nutrient charge fertilizers (PNCF) incorporated into each root medium were varied, and then, final chemical properties of the root media were analysed. The total porosity (TP), container capacity (CC), and air-filled porosity (AFP) were 81.3%. 39.9%, and 41.4% in ERH and 77.6%, 64.1%, and 13.5% in CRH, respectively. The percentage of easily available water (EAW, from CC to 4.90 kPa tension) and buffering water (BW, 4.91-9.81 kPa tension) were 11.37% and 5.27%, in ERH and 17.26% and 14.28% in CRH, respectively. The pH of ERH was 7.1, but it was extremely high in CRH such as 11.2. The EC and CEC were $1.31dS{\cdot}m^{-1}$ and $12.1meq{\cdot}100g^{-1}$ in ERH and $6.53dS{\cdot}m^{-1}$ and CEC 7.79 $meq{\cdot}100g^{-1}$ in CRH, respectively. The ranges of TP, CC and AFP in 4 selected media (PM + ERH, 6:4, v/v; CD + ERH, 8:2; PM + CRH, 7:3; CD+CRH 6:4) were 89.2-90.3%, 67.3-81.8%, and 8.3-21.9%, respectively. The pHs and ECs in root media containing peatmoss such as PM + ERH (6:4) and PM + CRH (7:3) were 4.0-4.3 and $0.33-0.365dS{\cdot}m^{-1}$, whereas those of CD + CRH were 7.4-7.9 and $1.282dS{\cdot}m^{-1}$. The pHs and ECs, however, analysed before and after the incorporation of PNCF in each root medium were not significant different. This result indicated that the incorporated fertilizers in PNCF to adjust medium pH did not dissolve enough to influence medium pH, but it is very normal in root media containing dolomitic lime and sulfur powder in adjusting pH. The Information obtained in this study may facilitate an effective formulation of root media containing rice hulls.

• Korean Journal of Pharmacognosy
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• v.12 no.2
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• pp.82-87
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• 1981

A novel iridoid glucoside was isolated from the root of Phlomis umbrosa Turcz. (Labiatae) 'Sok-dan' and named as Umbroside. It was obtained as amorphous powder and its molecular formula is C_{19}H_{18}O_{12}$. By enzyme hydrolysis it produced a stable aglucone and ${\beta}-D-glucose$. The structure of Umbroside was determined as 8-O-acetyl shanzhiside methyl ester. Antitumor activity of Labiatae plants was also tested.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.377-381
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• 2015

The content analysis of 6-gingerol, which is an active compound, in Zingiber spp. (Z. officinale and Z. mioga) and their commercial foods (ginger teas and powders) was conducted using high-performance liquid chromatography. A reverse phase system was used, with a gradient solvent system of water and acetonitrile. The 6-gingerol content was highest in the methanol extract of Z. officinale root (17.09 mg/g extract) and ginger powder B (15.92 mg/g extract). The results demonstrated that this method was simple and reliable for the quality control of Zingiber commercial foods.

• Korean Journal of Pharmacognosy
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• v.14 no.1
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• pp.5-8
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• 1983

Phlomis umbrosa Turcz. ('Sok-dan') is a perennial herb in Labiatae plants. Shanzhiside methyl ester was isolated from butanol extract of this plant. It was obtained as amorphous powder and its molecular formula is $C_{17}H_{26}O_{11}$. Its structure was determined by chemical reactions, spectral analysis and compared with authentic sample of its pentaacetate.