• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.679-682
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• 1994

The volatile sulfur compounds in raw and dried garlic (Allium sativum L.) under various temperatures (50, 60, 70 and $80^{\circ}C$ ) were separated, identified by GC and GC/MS. In hexane extracts of raw garlic, 8 volatile sulfur compounds were identified and 11 compounds were identified in steam distillation extracts. The volatile sulfur compounds of raw and dried garlic were mostly composed of diallyl disulfide, diallyl trisulfide, allyl methyl trisulfide. According to the increase of drying temperature total amounts of volatile sulfur compounds in the hexane extracts decreased to $40{\sim}75$$, and in the steam distillation extracts decreased to $10{\sim}20%$. The amounts of diallyl disulfide, allyl methyl trisulfide decreased more than other volatile sulfur compounds, but diallyl trisulfide comparatively decreased lower.

• Preventive Nutrition and Food Science
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• v.21 no.2
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• pp.138-146
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• 2016

In this study, we report the optimal extraction conditions for obtaining organosulfur compounds, such as cycloalliin, from garlic by using principal component analysis (PCA). Extraction variables including temperature ($40{\sim}80^{\circ}C$), time (0.5~12 h), and pH (4~12) were investigated for the highest cycloalliin yields. The cycloalliin yield (5.5 mmol/mL) at pH 10 was enhanced by ~40% relative to those (~3.9 mmol/mL) at pH 4 and pH 6. The cycloalliin level at $80^{\circ}C$ showed the highest yield among the tested temperatures (5.05 mmol/mL). Prolonged extraction times also increased cycloalliin yield; the yield after 12 h was enhanced ~2-fold (4 mmol/mL) compared to the control. Isoalliin and cycloalliin levels were inversely correlated, whereas a direct correlation between polyphenol and cycloalliin levels was observed. In storage for 30 days, garlic stored at $60^{\circ}C$ (11 mmol/mL) showed higher levels of cycloalliin and polyphenols than those at $40^{\circ}C$, with the maximum cycloalliin level (13 mmol/mL) on day 15. Based on the PCA analysis, the isoalliin level depended on the extraction time, while cycloalliin amounts were influenced not only by extraction time, but also by pH and temperature. Taken together, extraction of garlic at $80^{\circ}C$, with an incubation time of 12 h, at pH 10 afforded the maximum yield of cycloalliin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.73-77
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• 1993

This study was intended to investigate the effects of solvents, particle size of a sample, sample to solvent ratio, temperature and time on the extraction of garlic oleoresin. Among eleven solvents used for oleoresin extraction from garlic, the optimal solvent was methyl alcohol. The most appropriate particle size of garlic, extracting temperature and mixing ratio of garlic to methyl alcohol were 20mesh, $25^{\circ}C$ and 1 to 3(w/w), respectively. On the basis of yield in oleoresin extraction, optimum extracting time was about 4 hours. The yield of oleoresin under the above-mentioned conditions was 21.3%. "L" and "b" as color appearance were decreased, whereas "a"was increased slightly during 60 days storage at 5$^{\circ}C$, $25^{\circ}C$ and 4$0^{\circ}C$. Changes in the pyruvate content showed close relation to pH value. During storage pyruvate content of garlic oleoresin was decreased as increasing storage temperature.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.266-271
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• 2007

The genomes of different allexiviruses were isolated and cloned from virus-infected garlic plants (Allium sativum), which were collected from farm fields in the southern provinces in Korea. The partial nucleotide sequences of the genomes from different allexiviruses were clearly identified in the virus-infected garlic plants. The cloned partial genomes of viruses in garlic plants showed a greater than 90% homology to previously identified allexiviruses and classified into species of GarV-A, -B, -C, -D, -E, and -X, demonstrating that species of allexivirus found in the other countries in the world are also widely distributed in the garlic plants in Korea.

• Journal of fish pathology
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• v.23 no.1
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• pp.69-83
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• 2010

This study was aimed to investigate the effects of injection of garlic, Allium sativum, extract and immersion in garlic juice on the nonspecific immunity and the resistance against the artificial infection of Streptococcus iniae and Edwardsiella tarda of the olive flounder, Paralichthys olivaceus. The nonspecific immune mechanisms were assessed in terms of lysozyme activity, nitroblue-tetrazolium (NBT) assay and superoxide dismutase (SOD) activity etc. Relative percent survival (RPS) was assessed by the challenge with S. iniae BS10 or E. tarda KE-1. Almost of the garlic extract injected groups showed the enhanced level of the tested nonspecific immune factors. In the challenge test with S. iniae and E. tarda, RPS of 5% garlic extract pre-injected group was much higher than that of any other tested groups, respectively. Almost of the garlic juice immersion tested groups exhibited strengthened nonspecific immune defence factors, lysozyme activity, the number of lymphocytes and neutrophils, NBT reduction and SOD activity in kidney. In the challenge with S. iniae and E. tarda, RPS in the 0.25 g/L of garlic juice immersed group was much higher than any other tested groups, respectively. The results suggest that the garlic extract and juice would be effective to enhance the nonspecific immunity and protective ability of olive flounder against fish disease such as S. iniae and E. tarda.

• 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.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.315-317
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• 1993

To understand the molecular structure and pathogenesis mechanism of Korean garlic viruses (GV), virus particles were isolated from field-grown garlic leaves and RNA genome was isolated from them. It was used for constructing cDNA library for GV. Several cDNA clones for GV were isolated and classified into 4 different groups on the basis of cross Southern hybridization. Northern blot analysis of GV RNA with one of these cDNA clones shows that the clone is a cDNA for GV RNA.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.963-966
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• 2007

The objectives of this study were to identity antioxidant substance in heated garlic juice (HGJ). We evaluated the antioxidant activities of heated garlic juice exposed to 120, 130, and $140^{\circ}C$ for 2 hr. The HGJ was partitioned using the solvents of hexane, chloroform, ethyl acetate, butanol, and water. The ethyl acetate fraction of HGJ treated at $130^{\circ}C$ for 2 hr showed strong antioxidant activity; this extract was isolated and purified using silica gel column chromatography and semi-preparative high-performance liquid chromatography. The structure of the purified compound was determined using spectroscopic methods, i.e., ultraviolet, mass spectrometry, infrared, $^1H$ NMR, $^{13}C$ NMR, DEPT, HMBC, and HMQC. The isolated compound was identified as thiacremonone (2,4-dihydroxy-2,5-dimethyl-thiophene-3-one). Thiacremonone showed strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, with a 50% inhibition concentration ($IC_{50}$) of $22.25{\pm}0.44\;{\mu}g/mL$, which is much higher than that of the antioxidants ascorbic acid ($30.06{\pm}0.42\;{\mu}g/mL$), ${\alpha}$-tocopherol ($71.30{\pm}0.97\;{\mu}g/mL$), and butylated hydroxyanisole ($50.54{\pm}0.94\;{\mu}g/mL$).

• 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.

• Mycobiology
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• v.30 no.4
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• pp.240-243
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• 2002

Embellisia allii causing bulb canker of white garlic(Allium sativum) has been observed on harvested or stored garlic bulbs. Identification of the fungus was determined based on the symptoms and morphological characteristics on in vitro potato dextrose agar(PDA) and malt extract agar(MEA). Colonies were effuse, blackish brown to black, velvety or powdery. Conidia were solitary, almost straight, most commonly ellipsoidal(or subcylindrical) to ovoid, mid to dark brown, smooth, with very dark 1 to 6 transverse(commonly $3{\sim}4$) and occasionally 1 or 2 oblique or longitudinal septa, and $30.4{\times}13.4{\mu}m$(av.). Conidiophores were simple or branched, straight or flexuous, up to 80 ${\mu}m$ long and $5.1{\sim}10.2{\mu}m$ thick. Chlamydospores were developed through enlargement and repeated cellular division of several adjacent hyphal cells to form a complex of thickwalled cells. The conidial measurements of garlic isolates closely matched the previous description of E. allii.