• Journal of Life Science
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• v.17 no.5 s.85
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• pp.652-657
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• 2007

To make functional fresh-cut yam using natural spices, the water or the methanol extract was prepared from different kinds of natural spices including ginger, wasabi, black pepper, mustard, cinnamon, chinese pepper, garlic, thyme, rosemary, chamomile, and peppermint. The extraction yields were varied as spice sources and extraction solvents used. Among the water extracts, peppermint extract showed strong antithrombosis activity with 26-folds extended thrombin time, and the $IC_{50}s$ of the extracts from cinnamon and rosemary were $61.3{\mu}g/ml\;and\;84.3{\mu}g/ml$ in DPPH scavenging assay, respectively. Whereas, the antimicrobial activity of all water extracts was ignorable. Among the methanol extracts, the extracts from thyme, ginger, and cinnamon showed antimicrobial activity against yam putrefactive bacteria. Strong antioxidative activity was found in the extracts from cinnamon and thyme. Based on these results, the functional fresh-cut yam was prepared using the water extract from peppermint or cinnamon. The antioxidative and antithrombin activities in the fresh-cut yam were maintained at $4^{\circ}C$ for 24 hr. Our results suggest that the natural spices could be applied to production of functional fresh-cut yam.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.81-86
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• 2007

This study was conducted to evaluate the quality characteristics of pork jerky added with the extracts of paprika (Capsicum annuum L.) and Japanese apricot (Prunus mume Sieb. et Zucc.). Color stability, lipid oxidation, texture, and consumer acceptability of the pork jerky were also compared before and after storage of 70 days. The pork jerky added with 0.5% paprika extract and 3.5% Japanese apricot extract had the highest score for overall acceptability. The redness (a-value) of the pork jerky added with the natural extracts had a similar level as the one with nitrite. The extracts of paprika and Japanese apricot were also effective in inhibiting the lipid oxidation of the pork jerky during storage. In texture measurement, the total shear force of the natural extracts-treated sample was lower than that of control (the natural extracts-untreated samples). All sensory properties of the pork jerky were significantly (p<0.05) improved by the addition of the natural extracts. The results of this study indicated that the extracts of paprika and Japanese apricot could be used as natural agents for retarding color and lipid oxidations.

• Food Science and Preservation
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• v.17 no.1
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• pp.160-164
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• 2010

Chemical methods using browning inhibitors have been used to control the browning of chopped garlic. However, consumer demand for natural products is increasing, and we therefore investigated the antibrowning effect of natural licorice root extract on chopped garlic. We used a combination of licorice extract and citric acid. Chopped garlic was exposed to citric acid and licorice extract at various levels and L values were measured during storage at $10^{\circ}C$. Licorice extract was effective as an initial antibrowning, and a mixture of licorice extract and citric acid was effective in inhibition of browning during storage. The effective mixing ratio of licorice extract and citric acid was 5:5 and 2:8. This indicates that licorice extract and citric acid synergistically act to inhibit browning of chopped garlic. Licorice extracts with higher levels of glycyrrhizin were more effective as antibrowning agents for chopped garlic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1543-1549
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• 2015

Black rice bran, a by-product from rice milling process, is a good natural source of anthocyanin pigment. The purpose of this study was to determine the optimum conditions for anthocyanin extraction from black rice bran as well as the stability of anthocyanin extract according to different storage temperatures. The main anthocyanin in 'Heugkwang' rice bran was identified as cyanidine-3-glucoside (C3G) by HPLC and LC-MS/MS. The yield and C3G content of black rice bran extract were investigated with various extraction solvents, temperatures, and times. The results indicate that the optimum extraction solvent, temperature, and time were 50% ethanol, $70^{\circ}C$, and 2 h, respectively. The stability of anthocyanin extract was studied during a storage period of 168 days at various temperatures ($-20^{\circ}C$, $4^{\circ}C$, and room temperature). Hunter's values (L, a, and b) of anthocyanin extract increased, whereas C3G content continuously decreased up to 168 days. Variations in Hunter's values and C3G content become larger as storage temperature increased. Anthocyanin extract from black rice bran was very stable, as C3G content after storage at all temperatures was maintained at more than 90% of initial content. These results suggest that anthocyanin extract from black rice bran may be useful as a natural food colorant.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.335-340
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• 2013

The antimicrobial effect of the methanol extract of Inula britannica flowers against methicillin resistant Staphylococcus aureus (MRSA) was investigated. It was confirmed that the methanol extract is mainly composed of quercetin, which has antimicrobial properties. The antimicrobial effect of the methanol extract against 3 MRSA strains was determined by the disc diffusion method. The minimal inhibitory concentrations were ranged from 0.625 mg/ml to 1.25 mg/ml, and the minimum bactericidal concentrations were 2.5 mg/ml. Time kill kinetics revealed bactericidal activities, and the morphological alterations in S. aureus ATCC 33591 treated with the extract were observed using a scanning electron microscope. The methanol extract affected the expression of the resistant genes, mecA, mecI, and mecRI in mRNA. Therefore, the methanol extract of I. britannica flowers clearly demonstrated an antimicrobial effect against MRSA and these results suggest a potential for application as a natural antimicrobial agent.

• Food Science and Preservation
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• v.13 no.6
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• pp.762-768
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• 2006

To assess utilization of onions extract as natural food additives, ethyl acetate, ethanol and hot water extract of freeze dried onions (red, white and yellow) were exmined for their chemical component and nitrite scavenging activity. Contents of total organic acid and total free sugar were in the range of $135.4{\sim}1,2557mg%$ and $51.7{\sim}62.9%$ as dry matter bases, respectively, and then their content of three onions were higher in ethylacetate and hor water extracts than in ethanol extract. Contents of total phenol and total flavonoids were in the range of $9.3{\sim}$13.3 % and $159.8{\sim}584.1mg%$ as dry matter bases, respectively, and their content of red onion extract by three solvent were higher than those of other onion extract. Nitrite-scavenging activities (NSA) of onion extracts were increased by lowering pH and elevating onion concentrations, and their values of ethanol and hot water were about 55% in addition of 10 mg/mL of red onion extract showing that NSA of red onion was twice higher than that of the other onions. In conclusion, the result indicated that red onion extract was very effective to inhibit nitrosamine formation at low pH condition as natural nitrite scavenging agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.427-432
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• 2005

This study was performed to investigate the effect of natural plant extracts on acetylcholinesterase (AChE) activity and the free radical scavenging activity. The methanolic extracts of plants were tested for AChE inhibitory activity using Ellman's colorimetric method in 96-welled microplates and antioxidant activity as the scavenging effect of 1, 1-diphenyl-2-picryl hydrazyl radical (DPPH). The results showed that AChE activities were inhibited (about 20-30%) in whole plant extract of Daucus carota var. sativa, Hypericum erectum and Fragaria yezoensis. AChE activities were inhibited (about 32-34%) in stems extract of Gingko biloba and leaves extract of Rhododendrondron yedoensa var. poukhanense. Fruit extract of Zanthoxylum schinifolium inhibited (about 18%) AChE activity. And the DPPH scavenging effects as antioxidant activity were similar to L-ascorbic acid in whole plant extract of Fragaria yezoensis and fruits extract of Comus officinalis.

• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.92-97
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• 2004

Effect of AGI $({\alpha}-Glucosidase\;Inhibitor)-1120$, pine (Pinus densiflora) bark extract and Chaga mushroom (Inonotus obliquus) - and Chaga mushroom mycelium extracts on cellular $NF-{\kappa}B$ activation in malignant human keratinocytes (SCC-13) were evaluated to elucidate the possible correlation of $NF-{\kappa}B$ with antioxidant activity. The antioxidant activities of these natural products were examined in three different evaluation methods, i.e., lipid peroxidation value (POV) evaluation test, and 1,1diphenyl-2-picrylhydrazyl radical (DPPH) and nitric oxide (NO) scavenging test. In a cell-based $NF-{\kappa}B$ monitoring assay systern, all samples revealed the downregulatory profiles on the cellular $NF-{\kappa}B$ activity. AGI -1120 (1, 2 mg) and Chaga mushroom extract (0.05, 0.1 mg) downregulated the $NF-{\kappa}B$ activity in a dose-dependent manner. Chaga mushroom mycelium extract (5 mg) significantly inhibited the $NF-{\kappa}B$ activity (p<0.05). Although AGI-1120 and Chaga mushroom mycelium extract exhibited no antioxidant activities evaluated in pay, Chaga mushroom extract showed antioxidant in a dose-dependent manner at concentrations of $0.05{\sim}1$ mg. While AGI-1120 and Chaga mushroom extract possessed a relatively potential DPPH radical scavenging activity, the NO scavenging activity of Chaga mushroom extract $(SC_{50}:47\;{mu}g)$ was higher than the known antioxidant, vitamin C $(SC_{50}:77\;{mu}g)$. These results suggest that AGI-1120 and Chaga mushroom- and Chaga mushroom mycelium extracts may serve as an useful radical scavenging antioxidant agents with $NF-{\kappa}B$ inhibitory effect in human skin.

• Natural Product Sciences
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• v.13 no.3
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• pp.195-198
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• 2007

Hepatoprotective action of alcoholic extract of Bacopa monniera (BME) was evaluated on Dgalactosamine (D-GalN) induced rat liver toxicity. Bacopa monniera extract reduced the elevated serum enzyme activities of ALT, AST, ALP, LDH, ${\gamma}-GT$ and the formation of hepatic malondialdehyde induced by D-GalN. The alcholic extract of Bacopa monniera also significantly restored the decreased levels of glutathione and the decreased activities of glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase and glucose-6-phosphatase. Therefore these results suggest that Bacopa monniera has hepatoprotective effect against D-GalN induced hepatotoxicity.

• Carbon letters
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• v.24
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• pp.47-54
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• 2017

Different phytochemicals obtained from various natural plant sources are used as reduction agents for preparing gold, copper, silver and platinum nanoparticles. In this work a green method of reducing graphene oxide (rGO) by an inexpensive, effective and scalable method using olive leaf aqueous extract as the reducing agent, was used to produce rGO. Both GO and rGO were prepared and investigated by ultraviolet and visible spectroscopy, Fourier-transform infrared, scanning electron microscopy, atomic force microscopy, thermogravimetric analysis, cyclic voltammetry, X-ray photoelectron spectra, electrochemical impedance spectroscopy and powder X-ray diffraction.