• Journal of agriculture & life science
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• v.45 no.4
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• pp.113-120
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• 2011

In vitro antioxidant activities and acetylcholinesterase (AChE) inhibitory effects of solvent fractions from aged raw garlic extracts were investigated. Total phenolics fractioned by hexane, chloroform, ethyl acetate and water from Aged raw garlic extracts were 3.70, 23.63, 31.27 and 2.35 mg/g, respectively. We found that ethyl acetate fractions had the highest in ABTS radical scavenging activities, ferric reducing antioxidant power and inhibitory effect on auto-oxidation of linoleic acid. Intracellular ROS accumulation resulting from $H_2O_2$ treatment of PC12 cells was significantly reduced when ethyl acetate fractions were present in the medium compared to PC12 cells treated with $H_2O_2$ only. In addition, we found that ethyl acetate fractions from aged raw garlic extracts resulted in a dose-dependent manner on AChE inhibition. Consequently, our results suggest that ethyl acetate fractions from aged raw garlic extracts may be useful as decreasing agents of oxidative stress and AChE inhibitors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.27-34
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• 2016

Garlic has drawn attention as a food material for its anti-oxidative and anti-inflammatory properties as well as for prevention and treatment of cancer. In order to increase efficiency, various aging methods for garlic have been attempted. In particular, thermally processed garlic is known to have higher biological activities due to its various chemical changes during heat treatment. Therefore, in this study, we investigated the anti-oxidative effects of garlic extracts aged at low temperature ($60{\sim}70^{\circ}C$). In the results, 2,2-diphenyl-1-picrylhydrazyl and 2,2-azino-bis (3-ethylbenzo-thiazoline-6-sulfonate) radical scavenging activities and ferric reducing ability of low temperature-aged garlic (LTAG) were similar to those of raw garlic. LTAG also showed decreased lipopolysaccharide (LPS)-induced production of reactive oxygen species, although there were not significant differences among samples. In addition, xanthine oxidase activity was inhibited by LTAG; the 15 days and $60^{\circ}C$ extract showed outstanding inhibition compared with the others. To understand the molecular mechanisms behind the anti-oxidative activity of LTAG, we performed quantitative real-time PCR analysis. The 30 days and $70^{\circ}C$ extract upregulated mRNA expression of antioxidant enzymes such as Cu/Zn-superoxide dismutase (SOD), Mn-SOD, glutathione peroxidase, and catalase in LPS-stimulated RAW 264.7 cells. This result indicates that LTAG can be a functional food as a nature antioxidant and antioxidant substance.

• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.443-448
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• 2008

In this study, black garlic was produced by aging under high temperature $(70^{\circ}C)$ and high humidity (90% RH) conditions. Then, the physiological activity and antioxidative effects of its extract were compared to those of normal garlic extract. The black garlic extract had a 2.5-fold higher total polyphenol content than that of the normal garlic extract, showing levels of 10.0 mg/g and 3.7 mg/g, respectively. At the $1,000{\mu}g/mL$ concentration, the black garlic and normal garlic extracts had electron donating abilities of 101.9% and 12.9%, respectively. For their nitritescavenging effects, the normal garlic extract showed slightly higher scavenging activity than the black garlic extract at the 5 mg/mL concentration; whereas the black garlic extract had a slightly higher effect at concentrations above 20 mg/mL. In terms of their superoxide dismutase activities, the black garlic extract showed a 10-fold higher activity as compared to the normal garlic extract at the 20 mg/mL concentration. Furthermore, at 50 mg/mL, the angiotensin converting enzyme inhibitory effects of the normal garlic and black garlic extracts were approximately 52.7% and 88.8%, respectively. These results indicate that the antioxidant activity and ACE inhibitory effects of the black garlic extract were greater than those of the normal garlic extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1779-1784
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• 2015

This study was performed to investigate the effects of various garlic extracts on cholesterol synthesis in HepG2 cells. Raw garlic, grilled garlic, and freeze dried garlic were subjected to cold water extraction, and extracts were incubated at room temperature for 1 min or 60 min. The extracts were treated to HepG2 cells for 4 h, and cholesterol synthesis and mRNA expression level of HMG-CoA reductase were investigated. The alliin contents were reduced when garlic was incubated at room temperature for 60 min. Raw garlic extracts showed lower intracellular cholesterol contents compared to that of the control group. However, raw garlic extracts incubated for 60 min showed no differences compared to the control group. Freeze-dried garlic extract showed minimum intracellular triglyceride and cholesterol contents. Relative mRNA expression level of HMG-CoA reductase, a rate-limiting enzyme of cholesterol synthesis, decreased in the garlic extracts. Compared with 60 min, garlic extracts incubated for 1 min showed a reduced level of HMG-CoA reductase mRNA expression. The freeze-dried garlic extract reduced mRNA expression level of HMG-CoA reductase in a dose-dependent manner in cells treated with 5% of 0.2, 0.5, 0.8, 1.0, and 1.5 mg/mL in medium, and the effect was maxed out at dose of 5% garlic extract at 1.0 mg/mL in medium.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.285-292
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• 2014

In the course of study for development of functional food ingredients from aged black garlic (ABG), heat-treated ripe bulbs of Allium sativum L., the water extracts from raw-garlic (RG) and ABG, and the subsequent organic solvent fractions of ABG were prepared, and their antioxidant, antimicrobial, and antithrombosis activities were compared. The extraction yield of ABG was 4-folds higher than that of RG, and the contents of total polyphenol, total flavonoid, total sugar and reducing sugar in the ABG extract were 4-folds, 1.56-folds, 3.36-folds and 6.75-folds higher than those of the RG extract, respectively. In antioxidation activity assay, the extract of ABG showed minor scavenging activity against DPPH anion, but revealed strong scavenging activity against ABTS cation and nitrite. Especially, the ethylacetate fraction from the ABG extract demonstrated stronger antioxidation activity than the RG extract and other fractions. Although the antimicrobial and antithrombosis activities of the RG extract did not appear in the ABG extract, the ethylacetate fraction from the ABG extract had antibacterial activity against Staphylococcus aureus and Bacillus subtilis, and strong antithrombosis activity via the inhibition of prothrombin, blood coagulation factors and platelet aggregation. All extracts and fractions did not show any hemolytic activity against human red blood cells up to 5 mg/ml. Our results suggest that the ethylacetate fraction of ABG could be applicable to the development of functional food ingredients for antithrombosis agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.965-971
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• 2008

The antioxidant activities of hot water and ethanol extracts from fresh, steamed and black garlic were compared. The levels of phenolic compounds of extracts from fresh, steamed and black garlic were $0.81{\sim}0.99\;mg$/100 g and their contents were not significantly different. The contents of flavonoids in ethanol extracts, $0.96{\pm}0.05{\sim}1.06{\pm}0.09\;mg$/100 g, was higher than hot water extracts. DPPH radical scavenging activity was higher in ethanol extract. Although the highest level was $69.40{\pm}0.13%$ in concentration of 10 mg/mL from black garlic ethanol extract, ethanol extracts showed $50.55{\pm}1.40%$ in concentration of 15 mg/mL. Reducing power was significantly higher in black garlic extract and higher in the order of black garlic> fresh garlic> steamed garlic in ethanol extract. Hydroxyl radical scavenging activity was higher in ethanol extract, showing over 60% in concentration of 5 mg/mL. In oil emulsion, TBA value was significantly lower in hot water extracts from black garlic, however ethanol extracts were not significantly different. TBA value of ethanol extract were $1.49{\pm}0.08{\sim}2.11{\pm}0.16\;MA\;mg/kg$ and $1.33{\pm}0.18{\sim}1.62{\pm}0.19\;MA\;mg/kg$ from steamed and black garlic, respectively. Antioxidant activity to the linoleic acid was $72.71{\pm}2.17{\sim}88.74{\pm}3.70%$ in 1-day storage, but its level was increased at 4-day storage to $86.67{\pm}3.76{\sim}92.50{\pm}0.87%$.

• Journal of Life Science
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• v.20 no.5
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• pp.775-781
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• 2010

The antioxidant activities of hot water extracts from fresh, red and black garlic processed in low temperatures were compared. The chromaticity value of browning garlic was between that of fresh and black garlic. Red garlic was similar in browning intensity to fresh garlic. Also, total phenol, flavonoids, total pyruvate and thiosulfate contents were similar between fresh and black garlic. DPPH, ABTs, NO radical scavenging activity and reducing power of red garlic were significantly higher than fresh garlic, but lower than those of black garlic. $\alpha$-Glucosidase inhibitory activity in red garlic was similar to that in black garlic. Antioxidant activities of red garlic were higher than fresh garlic but lower than black garlic, and it was confirmed that antioxidant activity by production of browning material through the thermal process was the main parameter of the biological activity in the aged red garlic.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.477-484
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• 2014

The purpose of this study is to verify the antimicrobial effect of garlic and black garlic against pathogenic bacteria. For the comparative analysis of antibacterial effects of garlic, Ampicillin $10{\mu}g$ (BBL) was used as control antibiotics. Research experiments were conducted on each of November 2013 and January 2014. Susceptibility to the antimicrobial effect was measured through Kirby-Bauer disc diffusion method and verified according to the standard proposed by the CLSI. Antimicrobial effect of fresh garlic was higher regardless of the method to extract than Ampicillin $10{\mu}g$. In contrast, the manufacturing methods of the black garlic had no effective differentiations. In antimicrobial susceptibility test, black garlic showed resistance to all of 4 strains. However, in the ethanol-extract of fermented black garlic(natural aging of 15 days.) was found the small changes of the growth-inhibition-zone against S. aureus (8 mm)and E. coli(7 mm). This study proposes a variety attempts about the extraction methods of black garlic for the possibility of food preservation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.84-88
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• 2011

Some thermally processed foods have higher biological activities due to their various chemical changes during heat treatment. Especially, 5-hydroxymethylfurfural (HMF) is derived from dehydration of sugars and has been identified in processed garlic. The biological function of HMF have revealed as antisickling agent and thyrosinase inhibitor. This study was carried out to examine the formation of HMF and free sugars from the aged garlics when it is treated at 60 and $75^{\circ}C$ and different incubation periods from 7 to 35 days. HMF and free sugars from the hot-water extracts of aged garlics were analyzed with GC/MS, LC/MS, and HPLC. The amount of HMF was higher than at $75^{\circ}C$ and increasing incubation period. Among free sugars, the only fructose except glucose and sucrose was formed and converted to HMF at high temperature and long incubation period. However, fructose formed in low temperature during making of aged garlic was rarely converted to HMF. This result indicates that formation of HMF can be dependent on the temperature and incubation period for making aged garlic.