• Korean Journal of Food Science and Technology
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• v.47 no.5
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• pp.652-657
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• 2015

To produce mulberry-leaf tea abundant in ${\gamma}$-aminobutyric acid (GABA), mulberry leaves were subjected to two distinct anaerobic conditions ($N_2$ and vacuum) for 12 h before the manufacturing process. Subsequently, changes in the GABA content as well as that of other components were measured. In anaerobically treated mulberry leaves, GABA content markedly increased by 436-472% compared with the control, while the glutamic acid content decreased. However, few changes were observed in the contents of the general components (moisture, carbohydrate, lipid, protein, and ash) and water-soluble solids. Free sugar, catechin, and total phenol content decreased after anaerobic treatment. However, the sensory test scores were not different between the control and anaerobically-treated samples. Consequently, tea products, manufactured post nitrogen gas or vacuum treatment of leaves after harvest, showed functional properties without sensory loss.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.134-140
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• 2015

We studied to compare with the effect on the shoot growth and yield relavant to weed control methods in peach. As the results about 10 day intervals and 3 times investigation after each primary treatment, treatment plot of 2 times and 3 times with the herbicide, glufosinate ammonium, were 98.2~98.6% into $10^{th}$ day, 78.6~79.6% into $20^{th}$ day, 40.7~41.1% into $30^{th}$ day, fabric covering treatment showed 100%, 100% and 97.5% and treatment plot of machinery weeding were 92.1%, 56.4% and 36.4%, respectively. Also, we compared shoot growth for pre- and post-harvest. In the results, most of weed control methods showed better growth than control. Thus, the average number of standard fruits for treatment plot of 2 times with the herbicide and that of machinery weeding was different significantly in relation to control. Therefore, we think that the herbicide henceforth is well worth the application because treatment of 2 times or 3 times with the herbicide showed significant the control effect against all of 14 weed species surveyed in peach orchard and thus no inhibition for growth and number of standard fruits in peach trees.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.131-140
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• 2012

The hawthorn spider mite, Tetranychus viennensis, is a pest of apples and a quarantine pest from some countries that import apples from Korea. A controlled atmosphere and temperature treatment system (CATTS) was developed as an alternative disinfestation method to methyl bromide fumigation treatment, and has been applied to control various insects and other arthropod pests on fruits. We applied CATTS to disinfect T. viennensis under conditions that were previously developed to control the peach fruit moth, Carposina sasakii. First, T. viennensis was sampled from Japanese apricot, Prunus mume, and identified by its morphological characters. In addition, both cytochrome oxidase I (COI) and internal transcribed spacer (ITS) sequences supported the morphological identification. Second, the heat-tolerant developmental stage was determined in T. viennensis. When a $46^{\circ}C$ heat treatment was applied to egg, nymph, and adult stages of T. viennensis, adults were the most tolerant stage. Third, when heat temperature was used along with 1% $O_2$ and 15% $CO_2$, the mites showed a significant increase in susceptibility to the heat treatment. Finally, CATTS at $46^{\circ}C$ with 15% $CO_2$ and 1% $O_2$ for 30 min resulted in 100% mortality of all T. viennensis development stages. These results indicated that CATTS isapplicable to disinfest T. viennensis in post-harvest apples.

• Journal of Mushroom
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• v.18 no.1
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• pp.115-119
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• 2020

This study was conducted to investigate the effect of post-harvest CO₂ treatment on the quality of the 'Gonji-7ho' oyster mushroom. The harvested mushrooms were pre-cooled at 3℃ for 1 day and placed in a gas-tight chamber with 0%, 30%, or 50% of CO₂ concentration for 3 hours at 3℃. Next, 400 g of the oyster mushroom sample was packaged into 20-㎛ thick oriented polypropylene (OPP) film bags and stored at 4℃ for 21 days. Treatment with 30% of CO₂ treatment maintained the highest stipe firmness of the oyster mushrooms during storage. The stipe lightness (CIE L^⁎) was the highest at 14 and 21 days, while the stipe yellowness (CIE b^⁎) was the lowest at 2 and 7 days of storage. Therefore, we concluded that the 30% CO₂ treatment maintained the overall visual quality of the 'Gonji-7ho' oyster mushroom until 17 days of storage at 3℃. Our results suggest that the shelf life of 'Gonji-7ho' oyster mushroom could be extended by the postharvest application of 30% CO₂ for 3 hours during low temperature storage.

• Food Science and Preservation
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• v.18 no.4
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• pp.497-501
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• 2011

The object of this study was to evaluate the effect of gibberellins (GA) pasting on the bourse shoot, and not just on the fruit characteristics but also on the quality, of Niitaka pear (Pyrus pyryfolia L). The fruit stalk was treated with GA (control, 25mg/fruit stalk) 35 days after reaching full bloom. In the GA-treated tree, the occurrence of abnormal bourse shoot (52.5%) increased, and the spur bud and flower number decreased. The diameter of the GA-paste-treated fruit increased during the pear growth period with GA treatment. The diameter, length, and weight of the GA-paste-treated fruit increased at harvest time, but the hardness was lower than that of the control. The differences in soluble solid, acidity, and fruit color between the control and the GA-paste-treated fruit were not significant. Post-harvest, during the storage period, the hardness of the GA-paste-treated fruit was lower than that of the control, and its weight loss ratio was higher than that of the control on the $60^{th}$ days of storage.

• Food Science and Preservation
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• v.21 no.4
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• pp.468-472
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• 2014

The effect of pre-storage treatments was investigated to control the occurrence of fruit skin stain in 'Niitaka' pears. The incidence of fruit skin stains was significantly reduced when the fruits were stored in paper bags with a yellow inner color, compared to when they were stored in paper bags with blue and red inner colors. Additionally, the pear fruits that were harvested seven days earlier than their optimum maturity date developed less fruit skin stains in cold storage and retained their quality. Storage in polyethylene (PE) bags did not control the occurrence of fruit skin stains as effectively as did bag-free storage or storage in calcium-coated bags. The dipping of the pear fruits in a chlorine dioxide and calcium solution was highly effective in reducing the fruit skin stains compared to when they were not dipped or when they were dipped only in distilled water. In particular, a 1,500 times diluted solution of sodium dichloroisocyannurate (NaDCC) reduced the incidence of fruit skin stains and the size of the lesions. No stain was observed on the skin of the fruit with a water content lower than 67.7% (w/v) during its storage. In conclusion, packaging pear fruits in bags with an inner calcium coat and dipping them in a chlorine dioxide, calcium, or NaDCC solution can effectively reduce their skin stains during their storage.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.288-292
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• 1999

It was previously reported that cobalt(II) effectively suppresses the postharvest gravitropic response of snapdragon (Antirrhinum majus L.) (Kim et al. (1997) Agric. Chem. and Biotechnol. 40, 567-571). In this study, several factors affecting the suppression of the gravitropic response by cobalt ion were examined. When flower stalks of snapdragon were pretreated with several different cobalt salts, cobalt nitrate turned out to be the most effective not only in reducing the response but also in preserving the flower quality. We also tested the effects of various detergents which were added to cobalt(II) solution, finding that Tween-40 was the best among the tested with respect to the effectiveness as well as the flower quality. Based on these results, we optimized a protocol for the chemical treatment; that is, a suppressor solution containing 10 mM $CO(NO_3)_2$ and 0.05% Tween-40 was directly sprayed on the gravitropically sensitive region of cut flowers of snapdragon. The suppressor treatment gave rise to a significantly improved results when the flower stalks were stored at a lower temperature after the chemical treatment.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.290-296
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• 2017

In this study, using the surface dielectric barrier discharge (DBD) produced at atmospheric pressure to improve the physiological activities of quercetin was investigated. Quercetin (at 200 ppm) was treated using air DBD with an input power of 250 W. The tyrosinase inhibition effect and total phenolic content of quercetin increased from 38.96 to 91.58% and from 134.53 to 152.93 ppm, respectively, after 20 min of plasma treatment. The antioxidant activity of quercetin treated for 20 min in the lipid models was higher than that of quercetin treated for 0, 5, and 10 min. Furthermore, plasma-treated quercetin exhibited antimicrobial activity against Listeria monocytogenes, Salmonella Typhimurium, and Staphylococcus aureus, whereas activity was not shown in the control. Structural modifications of the quercetin molecule induced by plasma might be responsible for the improvements in its physiological activity. These results indicate that DBD plasma could be used to enhance the physiological activity of quercetin for various applications in food.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.713-717
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• 2008

In the present study, chronic effects of the hot water extracts of walnut seed (Juglans regia L.) (WSE) and Nelumbo nucifera seed (NSE) were investigated in mice exposed to 2 hr of restraint stress each day for 4 weeks. Corticosterone levels in serum were significantly increased in the vehicle-treated stressed group ($25\;{\mu}g/dL$) compared to that in the control group ($13\;{\mu}g/dL$). This stress induced gastric redness and lesions. However, treatment with WSE and/or NSE significantly protected the stomach from this lesion by 50-60% compared to that in the vehicletreated group. In the amygdala, the administration of WSE and/or NSE also reduced the immediate early gene (c-fos) expression by 70-90% vs. the vehicle-treated group. These suggest that WSE and/or NSE may reduce the appearance of symptoms induced by stress and these materials are useful as anti-stress foods, as natural products tend to be relatively safe compared to chemical products.