• The Korean Journal of Mycology
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• v.49 no.1
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• pp.87-100
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• 2021

This study aimed to isolate wild yeasts obtained from flowers and soil of the Wolpyung park, Daejeon city and Gykpo beach, Buan, Jeollabuk-do in Korea, and to further characterize previously unrecorded wild yeast strains. In total, 88 strains of 62 different species of wild yeasts were isolated from 75 samples obtained from the Wolpyung park. Among these, six strains of Trichosporon moniliiforme and four strains each of Papiliotrema flavescens and Candida melibiosica were isolated. Additionally, 39 strains of 30 different species of wild yeasts were isolated from 35 samples collected from the Gykpo beach. Among the 127 isolated wild yeast strains, 10 strains, including Apiotrichum porosum ASCM32-1, were previously unrecorded. All the 10 previously unrecorded yeasts were oval or global in shape, and three strains, including Candida athensensis WP4-90-3, formed spores. Three strains, including Vishniacozyma taibaiensis WP13-2, were halophilic yeasts which grew in 15% NaCl-containing YPD(yeast extract-peptone-dextrose) medium. Five strains, including C. athensensis WP4-90-3, showed 15% ethanol resistance. Cell-free extracts from Candida oleophila WP5-19-1 and Wickerhamomyces anomalus HO9-2 showed the highest β-glucuronidase inhibitory activity (49.0%) and neutrophil elastase inhibitory activity (38.4%), respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.1
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• pp.62-70
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• 2021

The purpose of this study was to determine the optimal digestible energy levels on pregnancy mares. Physical changes and fecal microorganism in pregnant horse and changes in birth characteristics of neonatal foals were investigated. The experiment was conducted by 18 mares (Jeju corssed bred, older than 36 months) into three treatment groups. The experimental diet consisted of 80%, 100%, 120% digestible energy levels based on NRC. The average daily intake was lower in the 120% (8.75±1.01) than the 100% (9.34±0.92), 80% (9.14±0.88) and there was significant difference (p<0.05). The feed efficiency was lower in the 120% than 80%, 100% (p<0.05). Total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride was higher in 120% than others (p<0.05). However there were no health problem and there was no difference between the treatment groups in the birth characteristics of neonatal foals. At the phylum level, Fibrobactres was difference by digestible energy levels, 80% (8.53%) was higher than 100%, 120%. At the genus level, Bacteroides and Kineothrix increased in fecal proportions with increasing digestible energy levels (p<0.05). Fibrobacter showed higher composition at 80% than 100% and 120% (p<0.05).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.29-36
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• 2021

Recently, phytochemicals in whole grains have received increasing attention because the increased consumption of whole grains and whole grain products has been associated with a reduced risk of chronic diseases. Among the phytochemicals in whole wheat, arabinoxylan influences various physiological activities and can aid the treatment of numerous health conditions, either directly or indirectly. In this study, 614 wheat germplasms, collected from the world, were cultivated in 2018 and harvested in 2019 in South Korea. The qualities of these whole grains, including seed protein content, were evaluated using the NIR spectrophotometric method, and arabinoxylan content was determined using enzymatic methods. The ash content was 0.36 to 2.80% and protein content was 7.66 to 20. The SDS-sedimentation for gluten complex ability ranged from 26.85 to 80.63 mL, and protein content showed a high correlation with SDS-sedimentation in the germplasms. Verify the result of the enzymatic method of arabinoxylan, the reliability of the experimental method was determined through repeatability, reproducibility, and recovery. The average value of the 614 resources was 51.64 mg/g of whole grain, and when classified according to the country of origin, the South Korean origin resources tended to have a higher content compared to the genetic resources of other countries. These results are expected to be used as basic data for setting standards for whole grain quality in wheat breeding systems.

• Journal of Mushroom
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• v.19 no.4
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• pp.300-309
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• 2021

This study was conducted to develop food and medicinal products containing useful components of Lentinula edodes in Codonopsis lanceolata and Platycodon grandiflorus for use as herbal medicine. We manufactured C. lanceolata (FCLM) and P. grandiflorus (FPLM) extract fermented with L. edodes mycelium. The effect of the two fermented products on proximate composition, free sugar, organic acid, 𝛽-glucan, ergothioneine, ergosterol, and vitamin D₂ levels, and 3T3-L1 preadipocyte cell growth were studied. The proximate composition analysis results showed that the crude fiber and crude fat content in FCLM was higher than that in FPLM, and the crude protein and soluble nitrogen content in FPLM was higher than that in FCLM. Free sugar analysis detected arabinose, glucose, and sucrose in both FCLM and FPLM, and the total free sugar content was high in FPLM. The organic acid content was lower in FCLM and FPLM compared to C. lanceolata and P. grandiflorus before fermentation. The 𝛽-glucan content was higher than that of L. edodes used as a control in both fermented products, FCLM and FPLM. The content of ergothioneine, an antioxidant, was higher in FCLM than in FPLM. Ergosterol content was highest in L. edodes which was used as a control, and the two fermented products showed similar content. Vitamin D₂ was detected only in FCLM and FPLM, and FPLM (0.58±0.01 mg%) showed a higher vitamin D₂ content than FCLM (0.47±0.01). FCLM and FPLM showed a higher level of cell viability for 3T3-L1 pre-adipocytes compared to non-fermented C. lanceolata and P. grandiflorus. In addition, FCLM and FPLM inhibited 3T3-L1 preadipocyte differentiation more than C. lanceolata and P. grandiflorus before fermentation, which may exert an anti-obesity effect.

• Journal of Ginseng Culture
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• v.4
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• pp.128-141
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• 2022

Baengnyeongdo Island, which belongs to Ongjin-gun, Incheon, is an island in the northernmost part of the West Sea in South Korea. Baengnyeong Island is the 15th largest island in Korea and covers an area of 51 km². The Korea Ginseng Corporation (KGC) investigated the possibility of growing ginseng on Baengnyeong Island in 1996. In 1997, thanks to the support of cultivation costs from Ongjin-gun, the first ginseng seedbed was built on Baengnyeong Island. In 1999, the seedlings were transplanted to a permanent field under a contract with KGC. In 2003, the first six-year-old ginseng harvest was performed, and KGC purchased all production according to the contract. Since then, KGC has signed on to grow ginseng until 2012 and purchased six-year-old ginseng until the fall of 2016. Since 2014, the GimpoPaju Ginseng Agricultural Cooperative Association has signed a ginseng production contract. According to a survey of nine 6-year-old ginseng fields (total 5,961 units) on Baengnyeong Island, the top five with good growth had a survival rate of 42.6 to 68%, and the bottom four with poor growth had an extremely low survival rate of 11.1 to 21.3%. The four fields with low survival rates were where hot peppers were planted before ginseng cultivation. It is believed that the excess nitrogen remaining in the soil due to the treatment of compost or manure during pepper cultivation causes ginseng roots to rot. The average incidence of Alternaria blight was 8.6%. Six six-year-old ginseng gardens were low at 1.1 to 4.7%, while the other three were high at 16.7 to 20.9%. It is assumed that the reason for the low survival rate and high incidence of Alternaria blight is a rain-leaking shield. Farmers used rain-leaking shields because the precipitation on Baengnyeong Island was smaller than on land. One field showed 3% of leaves with yellowish brown spots, a symptom of physiological disturbance of the leaf, which is presumed to be due to the excessive presence of iron in the soil. To increase the production of ginseng on Baengnyeong Island, it is necessary to develop a suitable ginseng cultivation method for the island, such as strengthening the field management based on the results of a scientific study of soil, using rain-resistant shading, and installing drip irrigation facilities. I hope that ginseng will become a new driving force for the development of Baengnyeong Island, allowing ginseng products and food to thrive in the beautiful natural environment of the island.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.3
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• pp.145-154
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• 2022

Due to abnormal weather conditions caused by climate change, natural disasters and damages are gradually increasing around the world. Global climate change as accompanied by warming is projected to exert adverse impact on production of potato, which is known as cool season crop. Even though, role of potato as a food security crop is expected to increase in the future, the climate change impacts on potato and adaption strategies are not sufficiently established. Therefore, this study was conducted to analyze the damage pattern of potatoes due to high temperature treatment and to evaluate the response of cultivars. T he high temperature treatment (35~38℃) induced heat stress by sealing the plastic house in midsummer (July), and the quantity and quality characteristics of potatoes were compared with the control group. T otal yield, marketable yield (>80 g) and the number of tubers per plants decreased when heat treatment was performed, and statistical significance was evident. In the heat treatment, 'Jayoung' cultivar suffered a high heat damage with an 84% reduction in yield of >80 g compared to the control group. However, in Jopung cultivar, the decrease was relatively small at 26%. Tuber physiological disturbances (Secondary growth, Tuber cracking, Malformation) tended to increase in the heat stress. Under heat conditions, the tubers were elongated overall, which means that the marketability of potatoes was lowered. T he tuber firmness and dry matter content tended to decrease significantly in the heat-treated group. T herefore, the yield and quality of tubers were damaged when growing potatoes in heat conditions. T he cultivar with high heat adaptability was 'Jopung'. T his result can be used as basic data for potato growers and breeding of heat-resistant cultivars.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.7-13
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• 1989

The present study was carried out to get the basic information for clarifying physiological mechanism of breaking dormancy and sprouting in Panax ginseng roots. Changes in Abscisic acid (ABA) content and Gibberellin (GA) activity were investigated in one-year-old root during stratification at 4$^{\circ}C$. 15$^{\circ}C$. and 15$^{\circ}C$ after 60day-treatment at 4$^{\circ}C$. Sprouting rate at 15$^{\circ}C$ was 35％ in 30days storage at 4$^{\circ}C$ and 100％ in longer than 60days, but there was no sprout in both the constant treatment at 4$^{\circ}C$ or 15$^{\circ}C$ regardless of the treatment period. The longer the period of low temperature treatment. number of days to the first and 50％ sprouting was shortened, and number of days to 50％ from first sprouting was also shortened. ABA content in the upper part of root(contained bud) was gradually increased at both 4$^{\circ}C$ and 15$^{\circ}C$ as the treatment period was extended. and the degree of increase was higher at 15$^{\circ}C$. In the lower part. it showed a slight increase at 15$^{\circ}C$. while showed little change at 4$^{\circ}C$ throughout the treatment period. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$, it was greatly increased in the upper part. while rather slightly decreased in the lower part of root. GA activity in the upper part was gradually decreased at both 4$^{\circ}C$ and 15$^{\circ}C$, and the degree of decrease was higher at 15$^{\circ}C$. In the lower part. it was similar tendency to those in the upper part. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$. it was remarkably increased in both the upper and lower part. The increase was great in the low Rf region, while the decrease appeared relatively in the high Rf region compared to those of 60day-treatment at 4$^{\circ}C$. The above results indicated that the breaking dormancy and sprouting of bud were closely associated with the degree of GA activities in response to temperature condition .during stratification rather than the direct effect associated with the changes in ABA content.

• Journal of Life Science
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• v.33 no.2
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• pp.129-137
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• 2023

Reactive oxygen species (ROS) play an essential role in a variety of cellular physiological phenomena. The present study assessed the signaling axis that mediates the lysophosphatidic acid (LPA)-induced migration of SKOV-3 cells. Insulin-like growth factor-1 (IGF-1) stimulated SKOV-3 cell migration in a time- and dose-dependent manner. Similarly, LPA stimulated SKOV-3 cell migration and the phosphorylation of Akt in a time- and dose-dependent manner. The pharmacological inhibition of LPA receptors (LPA₁/LPA₃) significantly suppressed LPA-induced SKOV-3 cell migration. However, IGF-1-induced SKOV-3 cell migration was not affected by the inhibition of LPA1 and LPA3. Pharmacological inhibition of phosphoinositide 3-kinase (PI3K) or Rho-associated kinase (ROCK) significantly suppressed LPA-induced migration, whereas the inhibition of MAPK kinase (MEK) had no effect. Inhibition of PI3K or ROCK completely suppressed LPA-induced ROS generation, and suppression of nicotinamide adenine dinucleotide phosphate oxidase (NOX) or chelation of ROS by N-acetylcysteine (NAC) blocked LPA-induced SKOV-3 cell migration. LPA-induced ROS generation was suppressed by silencing Rictor or Akt1 but not Raptor or Akt2. Silencing Rictor or Akt1 significantly suppressed LPA-induced SKOV-3 cell migration, whereas silencing Raptor or Akt2 had no effect. Finally, the overexpression of the constitutively active form Akt1 (CA-Akt1) significantly enhanced the LPA-induced migration of SKOV-3 cells. Given these results, we suggest that LPA stimulates SKOV-3 cell migration by ROS generation, which is mediated by the mTORC2/Akt1/NOX signaling axis.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.163-172
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• 2016

Four growing Hanwoo cattle weighing 200±11.7kg were used within 4×4 Latin square design to establish nutrient requirements for Hanwoo growing steers under severe heat stress. The steers were fed four different energy level diets; 100%(control), 100%(E100), 115%(E115) and 130%(E130) of energy levels of growing Hanwoo steers based on total digestible nutrient level suggested by the Korea Feeding Standard for Hanwoo using timothy hay and commercial concentrate. The steers in the control were housed with no stress, whereas the steers in the other groups were under severe heat stress. The severe heat stress significantly decreased(p<0.05) true digestibility of dry matter(i.e. control 81.5% vs E100 79.1, E115 77.0 and E130 76.0, respectively). The severe heat stress and different energy intake levels did not affect blood physiological metabolites and body temperature of the growing steers. Based on changes in average daily gain by different energy intake level, the equation(Y=0.235X+115.03) of energy requirement of growing Hanwoo steers without changes in body weight was calculated, indicating that, compared with the present energy intake suggested by Korean feeding standard, 15.03% of dietary energy for maintenance of growing Hanwoo steers under severe heat stress should be increased.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.517-526
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• 2023

The harvest time of the late-ripening 'Fuji' apple (Malus × domestica) is variable, depending on the coloration of the fruit skin. Ethephon, a plant growth regulator, promotes the ethylene production and induces physiological responses associated with fruit maturation in climacteric fruit crops, such as apples. This study aimed to investigate the effect of ethephon treatment on fruit characteristics after fruit enlargement, with the objective of proposing an economical and stable harvest control method for 'Fuji'/M.26 apples. Fruit characteristics were assessed at 10-days intervals following the application of 100 mg/L ethephon and mixture of 100 mg/L ethephon and 0.5% CaCl₂ at 145 days after full bloom (DAFB). Starch contents of ethephon-treated (ET) and ethephon with CaCl₂-treated (EC) apples began to decrease from 155 DAFB, and the starch contents of ET and EC at 10 days before harvest were similar to those of control at harvest time. Red coloration of fruit skin in EC was lower compared to ET but higher than control. The average fruit firmness was low in ET, while the control and EC exhibited similar levels of firmness. Fruit sugar acid ratios did not show significant differences between treatments. However, the titratable acidity of EC was significantly lower than that of the control at 10 days before harvest. Moreover, fruit sugar acid ratio of ET and EC at 10 days before harvest in 2021 was similar to their sugar acid ratio at harvest time. Therefore, it was thought that fruit maturation and skin coloration could be accelerated by 10 days from the harvest time through the combined treatment of 100 mg/L ethephon and 0.5% CaCl₂ at the end of fruit enlargement in 'Fuji'/M.26.