• Food Science of Animal Resources
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• v.30 no.4
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• pp.641-648
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• 2010

The objective of this study was to evaluate the pre-heating treatment effects on the antioxidant properties of ethanolic garlic and onion extracts. Garlic and onion with or without heating ($100^{\circ}C$, 30 min) were extracted with ethanol, and the total phenolic content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, iron chelating ability, reducing power, and antioxidant activity in a linoleic acid emulsion system were evaluated. Garlic (41%) had a higher drying yield than onion (11%). Regardless of pre-heating, ethanol extracts of onion resulted in an approximately 25-fold higher yield than those of garlic. Thermal treatment before extraction decreased the levels of ethanol-soluble phenolics for both garlic and onion. Regardless of pre-heating, the radical scavenging abilities of ethanol extracts from garlic were greater than the ethanol extracts from onion. The iron chelating abilities of ethanol extracts from fresh and heated garlic were 85 and 81% at 10 mg/mL, respectively, whereas those of onion extracts were 10 and 9% at the same concentration, respectively. However, no differences in reducing power between garlic and onion extracts were observed. Both garlic and onion inhibited the formation of hydroperoxide in linoleic acid emulsion systems when ethanol was used as a solvent. Overall, garlic extracts had greater antioxidant activity than onion extracts, and the antioxidant activity of garlic and onion extracts were not significantly affected by thermal treatment.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.593-595
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• 1993

The volatile components of garlic extracts were investigated. For experiment both crushed- and sliced-garlic were dried by air-drying and freeze-drying methods, followed by ether extraction. The extracts were analysed by GC and GC/MS. Sliced- and freeze-dried garlic extracts showed larger number of volatile components than crushed- and air-dried garlic extracts. The volatile components, allyl propyl disulifde, 2-vinyl-1,3-dithiane, 3-vinyl-〔4H〕-1,2-dithiin, 1,2-Bis (allyl)disulfane were found in sliced- and freeze-dried garlic extracts, methyl allyl trisulfide and 2,4-methyl furane in sliced- and air-dried garlic extracts, and disulfide in crushed- and air-dried garlic extracts.

• Food Science and Preservation
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• v.18 no.3
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• pp.349-357
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• 2011

This study was performed to examine the quality and antioxidant activity of pork ham with various levels of black garlic extracts. Pork ham manufactured from black garlic extracts with 15 brix (1% (H1), 1.5% (H2), 2% (H3)) and 30 brix (0.2% (H4), 0.5% (H5), 1% (H6) were stored for 28 days at $8{\pm}1^{\circ}C$ and analyzed with an interval of 7 days. In the sensory evaluation, the garlic odor was increased as the garlic extract adding level larger, whereas color, flavor, juiciness, texture and acceptability were not showed significant differences. The pH values of pork products were increased as the level of black garlic extracts increased. The shear force value of groups (H4~H6) with the addition of 30 brix extracts addition were significantly higher than those groups with 15 brix extracts addition (H1~H3) throughout the storage period. Furthermore, the TBARS (thiobarbutric acid reactive substance) content of the pork ham containing various levels of black garlic extract were lower than that of the control group as storage period increased. Thus, black garlic extracts have a potential application for the pork products to inhibit of lipid oxidation.

• Food Science of Animal Resources
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• v.39 no.4
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• pp.610-622
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• 2019

The aim of this study was to investigate the natural antioxidant activity of raw garlic (RG), aged black garlic (AG), and garlic fermented with Bacillus subtilis (FG) extracts on pork patty lipid oxidation throughout refrigerated storage. The total polyphenol, total flavonoid content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity of three different types of garlic extracts were measured. The total phenolic and flavonoid content of AG was significantly higher than that of FG and RG; FG also showed a significantly higher total phenolic content than that of RG (p<0.05). The DPPH and ABTS radical scavenging activity of AG and FG was significantly higher than that of RG and that of AG was significantly higher than that of FG (p<0.05). To investigate the effect of processed garlic extracts on pork patty lipid oxidation, freeze-dried extracts of RG, FG, and AG were added to the patties at levels of 0.5% (w/w). Patties containing 0.01% (w/w) ascorbic acid (AA) and patties without treatment (CON) were compared with patties containing garlic extracts. The pH value, 2-thiobarbituric acid reactive substances value, and volatile basic nitrogen value of pork patties containing AG and FG extracts were significantly decreased compared to the other groups (CON, AA, and RG; p<0.05). Taken together, these results suggest that AG and FG extracts possess strong antioxidative activity and can serve as natural antioxidative additives to prevent pork patty lipid oxidation.

• 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.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.123-130
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• 2005

Hydrogen-donating capacity, scavenging activity of reactive oxygen including superoxide anion radical and hydrogen peroxide, metal-chelating activity, and reducing power of garlic extracts were investigated. All tested garlic extracts exhibited in vitro antioxidant activities, with Uiseong extract showing highest hydrogen-donating and hydrogen peroxide-scavenging activities, and reducing power, followed by Seosan and Samchek extracts, in proportion to total thiosulfinate contents. Higher scavenging activity of superoxide anion radical was observed in Uiseong than Seosan and Samchek extracts. Metal-chelating activity increased in order of Uiseong < Seosan < Samchek, showing inverse relations to total thiosulfinate content. Garlic extracts of Uiseong and Seosan showed weak prooxidant activities and that of Samchek showed strong antioxidant activity against $Cu^{+2}$-induced human LDL oxidation. Protective effects on peroxyl and hydroxyl radical-induced DNA strand damages were observed in all tested garlic cloves. These results indicate growing conditions of garlic cloves affect total thiosulfinate content and antioxidant activities.

• Korean journal of food and cookery science
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• v.17 no.2
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• pp.117-122
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• 2001

Ground fresh garlic and 50% ethanol garlic extracts were added into ground porks in order to investigate their effects on pH, peroxide and TBA values of ground porks during storage at 4$\^{C}$. The grounded porks tested were devided into two groups of fresh and heated forks at 100$\^{C}$ for 10 minutes. A significant control effect of ground garlic and extracts was found on peroxide and TBA values during storage, particularly for those added with 20% ground garlic and 10% garlic extracts. The effects were maximum after storage of 4-6 days and then decreased thereafter The pH was generally decreased until 6 days followed by the increase. Addition of garlic and garlic extracts caused a little increase in pH and the pH changes were less than the changes of control. Eventhough the effects of garlic on pH, peroxide and TBA values were similar for both heated and fresh pork, heat treated one showed more changes than fresh pork.

• Journal of Korean Medicine for Obesity Research
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• v.21 no.2
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• pp.69-79
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• 2021

Objectives: This study aimed to compare the anti-obesity effects of raw and pickled garlic in vitro in 3T3-L1 preadipocytes. Methods: The pickled garlic samples comprised the following: garlic aged in vinegar (VG), garlic aged in soy sauce, and vinegar (1:1, v/v) (PG) and raw garlic (RG) as control. Hexane, butanol, and distilled water were used to prepare the fractions. The pancreatic lipase inhibitory activity was used as a measure of anti-obesity effects of the extracts. The lipid droplet accumulation and triglyceride content in the 3T3-L1 cells were measured using Oil red O staining and triglyceride assay kits, respectively. The adipogenesis related protein expression levels were analyzed using the kits and the western blot method. Results: The pancreatic lipase inhibitory activity of the garlic extracts (VG, PG, RG) was the highest in the butanol fraction, and the inhibitory effect was the highest in RG, followed by PG and VG. All garlic butanol extracts suppressed triglyceride accumulation in differentiated adipocytes (P<0.05) through the activation of cyclic adenosine monophosphate (AMP), AMP-activated protein kinase, carnitine palmitoyl transferase-1, and the inhibition of fatty acid synthase. Raw garlic extracts significantly inhibited the expression of proteins involved in adipogenesis as compared to pickled garlic. Conclusions: Raw garlic has the potential to be an effective natural material for reducing obesity compared to pickled garlic with vinegar or soy sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.805-812
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• 2010

DNA damage including base modifications, loss of base and breaks in DNA strands can occur by exposure to irradiation, smoking and several components of food. Unrepaired DNA damage is known to lead to cellular dysfunction, cell death, cancer, and other diseases such as arteriosclerosis and diabetes. The protective effect of garlic on oxidative stress induced DNA damage has been reported recently. In this study, we investigated the protective effect of garlic extracts prepared by different processing methods (raw garlic extracts, RGE; grilled garlic extracts, GGE; pickled garlic extracts, PGE) on leukocytic DNA damage using comet assay. Human leukocytes were incubated with ethanol and methanol extract of garlic at various concentrations (1, 5, 10, 50 ${\mu}g$/mL), followed by oxidative stimuli (200 ${\mu}M$ $H_2O_2$ or 200 ${\mu}M$ 4-hydroxynonenal (HNE)). The methanol and ethanol extracts of RGE, GGE, and PGE showed inhibitory activities of DNA damage induced by $H_2O_2$ or HNE. Especially methanol extract of RGE ($ED_{50}$; 13.3 ${\mu}g$/mL) had a higher antigenotoxic effect on $H_2O_2$ induced DNA damage than those of GGE (23.5 ${\mu}g$/mL) or PGE (24.5 ${\mu}g$/mL). HNE induced DNA damage tended to be effectively inhibited by the lower concentration of all garlic extracts. Therefore, garlic might have protective effects against oxidative DNA damage regardless of processing methods (raw, grilled, pickled) which are the general consumed forms of garlic in Korea.

• Research in Plant Disease
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• v.10 no.4
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• pp.349-352
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• 2004

Antimicrobial activity of garlic extracts of four local cultivars (Namdo, Goheung, Danyang and garlic imported from China) against several plant pathogenic bacteria and fungi was investigated. The garlic extracts exhibited marked in vitro antimicrobial activities against the Gram-positive and -negative bacteria as well as fungal pathogens. Of the four cultivars, two cultivars (Namdo and garlic imported from China) showed relatively good antimicrobial activities. Gram-positive bacteria, Clavibater michiganensis was most sensitive, whereas Burkholderia cepacia was the strong resistant towards garlic extracts. Results from the planta bioassays under greenhouse conditions indicated that garlic extracts significantly reduced the cucumber powdery mildew disease showing control value 59.7-61.9% compared with the nontreated controls.