• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1236-1239
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• 2006

Allyl alcohol (2-propen-l-ol), found in considerable amounts in heated garlic, was able to discriminate yeasts from bacteria and was approximately three orders of magnitude more inhibitory towards yeasts than bacteria. The average minimum inhibitory concentration (MIC) of allyl alcohol for bacteria and yeasts was 5.0% and 0.0056%, respectively. The unsaturated primary alcohols, including allyl alcohol and 2-buten-l-ol, seemed to work differently from all the other saturated alcohols and unsaturated secondary alcohols in inhibiting various yeasts. An alcohol dehydrogenase-negative (ADH$^-$) strain of Saccharomyces cerevisiae was as resistant to allyl alcohol as various bacteria, exhibiting an MIC of 5.0%. The unsaturated primary alcohols were apparently oxidized into the corresponding unsaturated aldehydes before they inhibited the yeasts.

• Journal of Biosystems Engineering
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• 제21권1호
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• pp.72-83
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• 1996

This study was performed to find out drying characteristics and develop drying model for the design of an efficient dryer or drying system of garlic. The basic model which describes drying phenomenon of garlic was first established. A series of drying test were conducted with two varieties of garlic(Uiseong, Namdo) at 9-different drying conditions (drying temperatures ; $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, relative humidities ; 20%, 35%, 50%) and statistical analysis was made to fit the data with exponential equation, approximated diffusion equation, page equation, thompson equation and wang equation, respectively. In this test, the effects of drying air temperature and relative humidity on the drying rate were undertaken. Finally, new drying model based on these experimental results was developed to describe the drying characteristics of garlic. Also, the volatile components of garlic extracts were investigated. For experiment both Uisoeng and Namdo garlic were dried by heated-air-drying, followed by ether extraction. The extracts were analysed by Gas chromatography/Mass spectrometer.

• Food Science and Biotechnology
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• 제16권6호
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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 ($50.54{\pm}0.94\;{\mu}g/mL$).

• 한국동물위생학회지
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• 제34권2호
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• pp.167-178
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• 2011

Garlic (Allium sativum L.) has long history of reputed value and actual use for its medicinal, antimicrobial and pesticidal properties. This study was conducted to find possible developments to natural food preservatives and natural antimicrobials from garlic extracts. The antimicrobial activities of raw garlic extract, heat, pH, temperature against pathogenic bacteria were investigated. E. coli, S. Enteritidis, L. monocytogenes, and S. aureus exhibited antimicrobial activities at 20% garlic extract, but no antimicrobial activity was seen in E. faecium. Raw garlic extract and garlic extract heated for 2 min at $95^{\circ}C$ showed strong antimicrobial activities, but the antimicrobial activity of garlic extract heated for 10 min at $95^{\circ}C$ was much less. The antimicrobial activities of 50% garlic extract adjusted pH 4.0~7.0 showed much the same, but the antimicrobial activities decreased at pH 8.0 or higher. The antimicrobial activities by storage $-18^{\circ}C$ of garlic extract showed much the same. When five strains were cultured for 72 hr at $35^{\circ}C$ in the TSB containing 1~10% garlic extract, viable cell number of five strains were decreased to $10^0{\sim}10^4$ CFU/ml even at 1% or 2.5% (E. faecium) after 24 hr, but later increased to $10^4{\sim}10^9$ CFU/ml after 72 hr. When five strains were cultured for 21 day at $4^{\circ}C$ in the TSB containing 1%, 2.5%, 5%, and 10% garlic extract, viable cell number of E. coli, S. Enteritidis, and S. aureus were decreased to $10^3$, $10^0{\sim}10^2$, $10^1{\sim}10^4$ CFU/ml after 21 day, respectively, but L. monocytogenes and E. faecium increased to $10^8$ and $10^6$ CFU/ml after 21 day.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.331-335
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• 2002

Aqueous extracts of garlic (Allium sativum) preparation were prepared after the samples were exposed to various heat treatments. A quantitative assessment of antimicrobial activities was carried out by determining the minimum inhibitory and microbicidal concentrations (MICs and MMCs) of the various extracts against some selected bacteria and fungi. The antimicrobial activity of garlic decreased as the heating temperature increased. This fact implies that alliinase may be the most critical rate-determinant to produce the activity when garlic is heated.

• Food Science and Biotechnology
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• 제15권6호
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• pp.838-843
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• 2006

The chemical processes involved in the formation of green pigment in crushed garlic cloves were investigated based on the principle of pink pigmentation in macerated onions. Intact greening and non-greening garlic cloves were either left untreated or heated at $90^{\circ}C$ for 3 min to inactivate enzyme activities. First, a colorless ether soluble compound referred to as color developer reacted with glycine (among all free amino acids) in garlic to form a second compound insoluble in ether. The latter compound then reacted with formaldehyde to yield the green colored pigment. Alliinase activity was necessary for the production of color developer and for the development of green pigment. In greening garlic that had been heat treated, green pigmentation did not proceed due to the heat-inactivation of alliinase, but the addition of alliinase solution into the garlic homogenates restored the pigmentation. However, this phenomenon was not observed in non-greening garlic with or without heat treatment. Finally, the mechanism of green pigment formation in crushed garlicis similar to that of pink pigment formation in macerated onions.

• 한국식품조리과학회지
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• 제18권1호
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• pp.73-80
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• 2002

마늘즙을 9$0^{\circ}C$에서 가열, 45$^{\circ}C$에서 감압 가열, -5$0^{\circ}C$에서 동결 농축하여 마늘 농축액을 제조하였고 이 때 농축 전후로 1% adipic acid와 1% sodium metabisulfite를 첨가하였다. 제조된 마늘 농축액을 4$^{\circ}C$와 $25^{\circ}C$에서 60일간 저장하면서 이들의 갈변도및 색도 변화를 측정한 결과, 전체적으로 adipic acid나 sodium metabisulfite가 첨가된 마늘 농축액이 무첨가 마늘 농축액에 비해 갈변이 억제되었으며 adipic acid 보다는 sodium metabisulfite를 첨가한 농축액에서 갈변억제 효과가 크게 나타났다. 첨가물의 첨가시기에 따른 효과를 보면 9$0^{\circ}C$ 가열 농축액에서는 농축 후에 sodium metabisulfite를 첨가한 것이 가장 갈변이 억제되었으며, 45$^{\circ}C$에서 감압 가열 농축액과 -5$0^{\circ}C$ 동결농축액에서는 농축 전에 sodium metabisulfite를 첨가한 농축액에서 갈변억제 효과가 크게 나타났다. 한편 -5$0^{\circ}C$ 동결농축액은 저장동안 무첨가액의 갈변이 크게 증가함으로써 갈변억제제의 사용이 필요한 것으로 나타났다. 9$0^{\circ}C$ 가열 마늘 농축액의 저장 중 색도 변화에서는 sodium metabisulfite를 첨가한 농축액의 L값이 adipic acid 첨가액보다 높고 a값과 b값은 낮아 갈변이 억제되었음을 알 수 있었다. 45$^{\circ}C$에서 감압 가열 농축액과 -5$0^{\circ}C$ 동결농축액에서도 sodium metabisulfite를 첨가한 농축액의 a값과 b값이 adipic acid를 첨가한 농축액보다 낮아 갈변억제에 sodium metabisulfite의 효과가 더 큰 것으로 나타났다.

• 한국축산식품학회지
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• 제30권4호
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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.

• 생명과학회지
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• 제26권4호
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• pp.446-452
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• 2016

마늘(Allium sativum L.)은 많은 아시아 지역의 나라에서 민간요법 및 추출물을 이용하여 다양하게 사용하고 있다. 국내 전통채소류들은 다양한 기능성과 강한 생리학적 활성을 가지고 있으며, 기능성 식품재료로 사용이 가능하다. 본 연구는 유산균을 이용하여 고체마늘 발효에 따른 생리활성을 조사하고자 하였다. 마늘 고체 발효를 위해 유산균을 한국전통 발효식품인 젓갈로부터 분리 및 KCTC로 부터 분양 받아 사용하였다. 발효유산균 선별은 MRS 고체배지에 디스크법을 이용하여 마늘 착즙액에 저항을 보이며 증식하는 유산균을 선택하였다. 선별된 유산균을 이용한 마늘 고체발효 추출물의 총 폴리페놀과 플라보노이드 농도가 731.0-845.2 ug/g과 92.68-413.58 ug/g로 각각 조사되었다. 그리고 DPPH 라디컬 활성과 SOD 유사활성은 양성대조구인 비타민 C 50 ppm 보다 높은 활성을 보였다. 또한, 항당뇨 활성인 α-glucosidase 저해활성은 유산균 발효마늘에서 양성대조구인 acarbose 50 ppm 보다 높은 저해활성을 보이는 것으로 조사되었다. 본 연구결과 유산균 발효 마늘의 생리학적 활성을 증대를 통해 향후 항산화 활성과 항당뇨 활성을 갖는 유산균 발효 마늘의 개발을 위해 유산균을 활용이 가능하며, 발효물을 이용하여 기능성 식·음료 소재로의 개발 가능성을 보일 것으로 사료된다.

• 한국식품영양과학회지
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• 제36권12호
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• pp.1637-1642
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• 2007

생마늘과 열처리에 따른 마늘의 향기 특성과 향기추출물의 항산화활성을 확인하고자 국내산 한지형 마늘 3종(단양, 서산, 의성마늘)과 난지형 마늘 3종(남해, 남도, 대서마늘), 중국산 마늘에 대하여 simultaneous distillation and extraction(SDE) 방법으로 향기 성분을 추출하여 GC/MS로 동정하고 항산화활성을 측정하였다. 생마늘의 주요 향기성분은 allyl methyl sulfide, methyl-2-propenyl disulfide, diallyl disulfide, 2-ethylidene-1,3-dithiane, methyl-2-propenyl trisulfide, di-2-propenyl trisulfide 및 2-vinyl- 4H-1,3-dithiin 등으로 나타났다. 항산화활성이 우수한 것으로 알려진 diallyl disulfide, methyl-2-propenyl trisulfide 및 di-2-propenyl trisulfide 등은 중국산 마늘보다 한지형 마늘이 많이 함유하고 있었다. 향기성분은 열처리시 2-propanone, allyl mercaptan, methyl formic acid, 2-methyl butanal 2-methyl thiophene, methyl pyrazine, 2,2-dimethyl-1,3-dithiane 및 2-propenyl propyl disulfide 등이 새롭게 생성되었으며, allyl methyl sulfide, allyl alcohol 및 allyl sulfide 등의 분자량이 작은 화합물의 함량이 증가하였다. 산지별 생마늘의 향기 추출물에 대한 항산화활성은 농도 의존적으로 증가하였으며, 단양, 남해 및 중국산은 각각 20.07, 34.62 및 9.71%의 항산화활성을 나타내었고, 열처리 후에는 각각 79.90, 93.59 및 77.26%로 증가하였다.