• Applied Biological Chemistry
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• v.45 no.4
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• pp.212-217
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• 2002

We purified polyphenols from persimmon leaf and tested their biological activity. The 60% acetone extract was lyophilized and applied to test enzyme inhibition of glucosyltransferase and tyrosinase. GTase was 82.4% inhibited at $1.8{\times}10^{-1}$ mg/ml and tyrosinase 21.7% inhibited at 0.8 mg/ml. The acetone extract was fractionated into F-1, 2, 3, 4, 5 by Sephadex Q-50 gel filtration and the fraction-1 and 2 showed higher enzyme inhibition activity than the other fractions. To the Proteinase K treatment and autoclaving of the two fractions had no effect on the enzyme activity, but these results suggested that active fraction was not protein but phenol ring completed compounds. By Sephadex LH-20, MCI-gel and Bondapak $C_{18}$ column chromatographies, compouds 1, 2, 3 and 4 from F-1 fraction, compounds 5 and 6 from F-2 fraction and compounds 7 , 8 from F-3 fraction were purified and re-crystallized. The purified compounds was assumed to be condensed tannins of frame flavan-3-ol frame on the basis of color reagent reaction and to be a mixture of monomer, dimer and trimer according to TLC analysis.

• Journal of Life Science
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• v.22 no.7
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• pp.904-911
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• 2012

Yacon has been used in folk medicines as a medicinal tea for hypoglycemia treatment. In a recent study described herein, antioxidative, antibacterial, antifungal activities, and cell-protective functions of yacon leaves have been reported. To evaluate the effects on fibrosis on pancreatitis, the efficacy of 1% of yacon extract (YE) on dibutyltin dichloride (DBTC) (8 mg/kg)-induced pancreatitis in rats was examined. On the 21st day after the DBTC treatment, a large increase in collagen was observed in the pancreas in the DBTC-treatment group (DT). But this was noticeably decreased with YE. In relation to the expression of COX-2, there was no response or a very weak response in the pancreas of the control group (CON). However, in DT, strong expression of COX-2 was observed in the pancreas on the 14th day, and COX-2 was present in inflammatory cells in the pancreas of the DT, especially on the 21st day. The expression was decreased for YE compared with DT. A remarkable increase in TGF-${\beta}1$ expression was observed in inflammatory cells in the pancreas in DT on the 21st day, whereas the expression was not found in YE after 21 days. However, on the 21th day, TGF-${\beta}1$ expression was increased in acinar cells of YE compared with DT. VEGF expression was very similar to the expression of in the pancreas. These results suggest that YE has an inhibitory effect on DBTC-induced pancreatic fibrosis.

• Applied Biological Chemistry
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• v.47 no.1
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• pp.72-77
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• 2004

The purpose of this research was to determine the effect of phenol compounds from green tea leaves and surfactant micelles on lipid oxidation in com oil-in-water emulsion (O/W). The concentration of phenol and surfactant in continuous phase of the O/W with exceed Brij 700 and phenol compounds was measured. The particle size of O/W with phenol (100 ppm) increased with increasing added exceed surfactant $(0{\sim}2.0%)$ and the concentration of surfactant and phenols in the continuous phase higher than these of control. Lipid oxidation rates, as determined by the formation of lipid hydroperoxides and headspace hexanal, in the O/W emulsions containing phenol compounds (100 ppm) and exceed surfactant $(0{\sim}2.0%)$ decreased with increasing concentration of exceed surfactant. The ability of the phenol compounds and exceed surfactant to inhibit hydroperoxide and headspace hexanal producing as lipid oxidation in O/W was BHT>procyanidin B3-3-O-gallate> (+)-gallocatechin > (+)-catechin and 2% > 1 % > 0% of exceed surfactant. These results indicate that phenol compounds and exceed surfactant could alter the physical location of hydroperoxide in O/W.

• Journal of Life Science
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• v.27 no.3
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• pp.355-360
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• 2017

Consumption of high doses of ethanol can lead to amnesia, which often manifests as a blackout. This incoordination of blackout may be a major cause in various social problems in alcohol consumption. However, there is still no treatment for preventing these alcohol-induced problems. Hydrangeae dulcis folium is a drug or a tea which is made from the fermented and dried leaves of Hydrangea serrata Seringe. The present study, we tested the ethanol extract of the Hydrangeae dulcis folium (EHDF) on ethanol-induced psychological deficits. To test behavioral deficits, an object recognition test was conducted using a mouse model. To evaluate synaptic deficits, N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic potential EPSP and long-term potentiation (LTP) in the mouse hippocampal slices were tested, as they are known to be vulnerable to ethanol and are associated with ethanol-induced amnesia. In the tests, ethanol (1 g/kg, i.p.) impaired object recognition memory, but EHDF (10 or 30 mg/kg) prevented this impairment in object recognition test. Interestingly, EHDF ($30{\mu}g/ml$) significantly ameliorated ethanol-induced LTP and NMDA receptor-mediated synaptic transmission in the hippocampal slices. EHDF prevented ethanol-induced object recognition memory deficits induced by ethanol. Interestingly, EHDF significantly ameliorated ethanol-induced LTP and NMDA receptor- mediated synaptic transmission in the hippocampal slices.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.785-792
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• 2020

ʟ-Theanine, found in green tea leaves has been shown to positively affect immunity and relaxation in humans. There have been many attempts to produce ʟ-theanine through enzymatic synthesis to overcome the limitations of traditional methods. Among the many genes coding for enzymes in the ʟ-theanine biosynthesis, glutamylmethylamide synthetase (GMAS) exhibits the greatest possibility of producing large amounts of production. Thus, GMAS from Methylovorus mays No. 9 was overexpressed in several strains including vectors with different copy numbers. BW25113(DE3) cells containing the pET24ma::gmas was selected for strains. The optimal temperature, pH, and metal ion concentration were 50℃, 7, and 5 mM MnCl₂, respectively. Additionally, ATP was found to be an important factor for producing high concentration of ʟ-theanine so several strains were tested during the reaction for ATP regeneration. Baker's yeast was found to decrease the demand for ATP most effectively. Addition of potassium phosphate source was demonstrated by producing 4-fold higher ʟ-theanine. To enhance the conversion yield, GMAS was additionally overexpressed in the system. A maximum of 198 mM ʟ-theanine was produced with 16.5 mmol/l/h productivity. The whole-cell reaction involving GMAS has greatest potential for scale-up production of ʟ-theanine.

• Korean journal of applied entomology
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• v.54 no.2
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• pp.99-109
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• 2015

Insecticidal and antifeeding activities of 29 commercialized eco-friendly organic products for managing plant diseases and insect pests against Plutella xylostella larvae, Spodoptera exigua larvae, Frankliniella occidentalis adults, and Myzus persicae adults were tested using spraying and leaf dipping bioassays under laboratory conditions. Products containing 60% Sophora extract (EOIS) and mixtures (EOISm) with Sophora extract, Stemona japonica extract, Melia azedarach extract, and Nepeta cataria extract as well as mixtures (EOISc) with Sophora extract, Chenopodium ambrosioides extract, and Melia azedarach extract as active ingredients showed strong insecticidal activity at recommended concentration against P. xylostella larvae. At half concentration, their insecticidal activities were decreased under 50%. The EOIS gave good insecticidal activity against S. exigua larvae and also showed 85% and 95% insecticidal activity at 24 and 48 hours after treatment to F. occidentalis adults, respectively. For M. persicae adults, EOISm and mixtures (EOIR) containing rape seed extract, neem extract, and castar oil produced 93% and 68% insecticidal activity, but their activities did not be increased at double concentration. EOISm only showed 100% contact toxicity against M. persicae adults exposed to dipping leaves. Interestingly, the insecticidal activity of EOIR and EOICi (citronella oil and derris extract) against M. persicae adults was increased with exposed time and concentration. In addition, EOICe (cedar oil), EOIS, EOISm, EOISc, EOIM (microorganism), EOIR, EOIPe (plant extract), and EOIT (tea tree extract) gave strong antifeeding activity against S. exigua and P. xylostella larvae. EOIB, EOIBs, EOIM, EOICi, and EOIMc showed above 70% antifeeding activity to the lepidopteran larvae. These results indicate that mixtures containing 2 to 3 plant extracts with Sophora extract show good activities against insect pests, although the difference of insecticidal and antifeeding activities was produced depending on both a tested insect species and an active ingredient or concentration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.113-123
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• 2020

Global climatic change and increasing climatic instability threaten crop productivity. Due to climatic change, drought stress is occurring more frequently in crop fields. In this study, we investigated the effect of treatment with hydrogen peroxide (H₂O₂) before leaf development on the growth and yield of sorghum for minimizing the damage of crops to drought. To assess the effect of H₂O₂ on the growth of sorghum plant, 10 mM H₂O₂ was used to treat sorghum leaves at the 3-leaf stage during growth in field conditions. Plant height, stem diameter, leaf length, and leaf width were increased by 7.6%, 9.6%, 8.3% and 11.5%, respectively. SPAD value, chlorophyll fluorescence (Fv/Fm), photosynthetic rate, stomatal conductance, and transpiration rate were increased by 3.0%, 4.9%, 26.0%, 23.4% and 12.7%, respectively. The amount of H₂O₂ in the leaf tissue of sorghum plant treated with 10 mM H₂O₂ was 0.7% of the applied amount after 1 hour. The level increased to approximately 1.0% after 6 hours. The highest antioxidant activity measured by the Oxygen Radical Absorbance Capacity assay was 847.3 µmol·g^-1 at 6 hour after treatment. However, in the well-watered condition, the concentration of H₂O₂ in the plant treated by the foliar application of H₂O₂ was 227.8 µmol·g^-1 higher than that of the untreated control. H₂O₂ treatment improved all the yield components and yield-related factors. Panicle length, plant dry weight, panicle weight, seed weight per plant, seed weight per unit area, and thousand seed weight were increased by 8.8%, 18.0%, 24.4%, 24.7%, 29.9% and 7.1%, respectively. Proteomic analysis showed that H₂O₂ treatment in sorghum increased the tolerance to drought stress and maintained growth and yield by ameliorating oxidative stress.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.226-236
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• 2020

This study was designed to evaluate the biological activities and main constituents of different parts (fruit, leaf, and stem) of aronia (Aronia melanocarpa). The total phenolic and flavonoidcontents, DPPH and ABTS⁺ radical-scavenging activity, reducing power, and ferric reducing/antioxidant power were observed to follow the order of: leaves > stems > fruits, regardless of extraction solvents. The inhibitory activity against lipopolysaccharide-induced NO production in Raw 264.7 cells was significantly higher in the aronialeaf extract-treated group than in the groups treated with stem and fruit extracts. The ultra-performance liquid chromatography (UPLC) analysis was mainly composed of routine. In addition, the highest content level was measured in the case of the catechinmemberepigallocatechin witha higher value than that found in green tea. Theresults of this studyprovide useful information for understanding the chemical constituents and biological activities of aroniafruits and byproducts.

• The Korean Journal of Pesticide Science
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• v.15 no.1
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• pp.36-47
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• 2011

This study was performed to investigate the contaminated status of endocrine disruptor-suspected pesticides in agricultural products distributed in northern Seoul in 20l0. We analyzed 33 kinds of pesticides by multiresidue analysis method in 3,081 samples. Twelve pesticidcs were detected 600 times and violated 22 times from the agricultural products. The highest frequency of detection was procymidone and that of violation was endosulfan. The highest rates of detection divided violation times as diazinon. In agricultural products, 466 samples had pesticide residues and 22 samples violated the maximum residue limits (MRLs). Agricultural products were also classified by type and red pepper powder belonged to the others was the highest detection rate at 70.7%, fruiting vegetables 35.3%, tea leaves 23.6%, stalk and stem vegetables 21.2%, fruits 14.6% and leafy vegetables 11.2%. The rates of violation sample were stalk and stem vegetables 1.1%, leafy vegetables 1.0% and roots and tubers 0.4%. Leek was to be managed primarily because it had the high detection and violation ratio and was detected together several pesticides.

• Journal of Food Hygiene and Safety
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• v.37 no.6
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• pp.418-428
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• 2022

The purpose of this study was to obtain the codex classification information on the primary food commodity (fresh state) of processed foods of plant origin that are included in the Codex Classification of Foods and Animal Feeds. Furthermore, whether or not the primary food commodity is included in the primary food classification from the Food Code of Korea was investigated. The results are summarized as follows: First, the Codex Classification information (number of classification codes/number of the primary food commodity group that fresh commodities of processed foods are classified/number of primary food commodity that is not included in the Codex Classification) by a processed food group appeared to be 46/8/0 for dried fruits, 76/11/1 for dried vegetables, 54/4/12 for dried herbs, 36/1/0 for cereal grain milling fractions, 17/4/3 for oils and fats (crude), 34/8/9 for oils and fats (refined), 20/8/0 for fruit juices, 3/2/0 for vegetable juices, and 19 codes for teas (in the Codex Classification, the primary food commodity group for tea does not exist). Second, the number of the primary food commodities not included in the Food Code of Korea was 9 for dried fruits, 14 for dried vegetables, 35 for dried herbs, 0 for cereal grain milling fractions, 6 for teas, 3 for oils and fats (crude), 9 for oils and fats (refined), 2 for fruit juices, and 0 for vegetable juices. Third, it was demonstrated that caution should be exercised when using Codex Classification due to differences in food classification between Codex and Korea, such as coconut (Codex, as tree nut as well as assorted tropical and sub-tropical fruit) and olive (Codex, as assorted tropical and sub-tropical fruit as well as olives for oil production), as well as special cases in the Codex Classification, such as dried chili pepper (Codex, as spice), tomato juice (Codex, as vegetable for primary food commodity and as fruit juice for juice) and ginger (Codex, as spice for rhizome and not including as primary commodity for leaves).