• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.68-76
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• 2001

We have employed chemical modification to identify amino acids essential for the catalytic activity of alliinase (EC 4.4.1.4) from garlic (Allium sativum). Alliinase degrades S-alkyl-L cysteine sulfoxides, causing the characteristic odor of garlic. The activity of alliinase was rapidly and completely inactivated by N-bromosuccinimide(NBS) and slightly decreased by succinic anhydride and N-acetylimidazole. These results indicate that tryptophanyl, lysyl, and tyrosyl residues play an important role in enzyme catalysis. The reaction of alliinase with NBA yielded a characteristic decrease in both the absorbance at 280 nm and the intrinsic fluorescence at 332 nm with increasing reagent concentration of NBS, consistent with the oxidation of tryptophan residues. Kinetic analysis, fluorometric titration of tryptophans and correlation to residual alliinase activity showed that modification of only one residue present on alliinase led to complete inhibition of alliinase activity. To identify this essential tryptophan residue, we employed chemical modification by NBS in the presence and absence of the protecting substrate analogue, S-ethyl-L-cysteine (SEC) and N-terminal sequence analysis of peptide fragment isolated by reverse phase-HPLC. A fragment containing residues 179-188 was isolated. We conclude that Trp182 is essential for alliinase activity.

• The Korean Journal of Food And Nutrition
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• v.12 no.1
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• pp.55-62
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• 1999

Changes in the alliinase activity during the aging of pickled garlic samples prepared by the several methods were investigated. The activity of alliinase in raw garlic was 8,37 units/mg protein. The ac-tivity in the garlic pickled with swoy sauce was reduced to 4.57 units/mg with 52% remaining by 1st week of pickling and to 1.05 units/mg protein with 12% remaining by 2nd week of pickling. The ac-tivity of alliinase in the garlic pickled with vinegar was 2.79 units/mg protein with 32% remaining by 1st week of pickling and was 0.26 units/mg protein only with 3% remaining by 2nd week of pickling. The activity of alliinase in the garlic pickled with 10% salt solution was 5.06 units/mg protein with 58% remaining by 1st week of pickling. After one week pickling the juice of pickled garlic was removed. Then garlics were pickled again with vinegar. The allinase acting in was reduced to 0.85 units/mg pro-tein with 10% remaining by 2nd week of pickling. The activity of alliinase in the garlic pickled with vin-egar was 2.79 units/mg protein with 32% remaining by 1st week of pickling. The juice of pickled garlic was removed after one week. Then the galics were again pickled with saysauce. The allinase activity in the garlic the garlic pickled again with soy sauce was reduced to 0.43 units/mg protein with 5% remain-ing by 2 week of pickling.

• Journal of environmental and Sanitary engineering
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• v.22 no.1 s.63
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• pp.57-66
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• 2007

Changes in the alliinase activity during the hot air drying and vacuum freeze drying of garlic samples treated as the whole, sliced and crushed state were investigated. The specific activity of alliinase in raw garlic was 8.52 units/mg protein. The activity in the whole garlic prepared by the hot air drying for 8 hrs was reduced remarkably to 5.22 units/mg protein with 61% remaining and to 4.25 units/mg protein with 50% remaining for 36 hrs. The activity in the sliced garlic prepared by the hot air drying for 36 hrs was reduced to 3.55 units/mg protein with 42% remaining and the activity in the crushed garlic prepared by the hot air drying for 36 hrs was reduced to 3.12 units/mg protein with 37% remaining. The garlic sample sliced or crushed was higher than the whole state in the efficiency of drying but was lower in the remaining activity of alliinase. The activity in the whole garlic prepared by the vacuum freeze drying for 8 hrs was reduced to 7.21 units/mg protein with 85% remaining and to 5.53 units/mg protein with 65% remaining for 36 hrs. The activity in the sliced garlic prepared by the vacuum freeze drying for 36 hrs was reduced to 4.55 units/mg protein with 53% remaining and the activity in the crushed garlic prepared by the vacuum freeze drying for 36 hrs was reduced to 4.16 units/mg protein with 49% remaining. The remaining activity of alliinase in the garlic samples prepared by the vacuum freeze drying was higher than the remaining activity in the garlic samples prepared by the hot air drying.

• Culinary science and hospitality research
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• v.14 no.1
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• pp.144-151
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• 2008

This study investigated the changes in the contents of allicin and diallyl disulfide and in the alliinase activity during the vacuum freeze drying of onion samples treated as the whole, sliced and crushed forms. The contents of allicin and diallyl disulfide in raw onions were 26.40ppm and 2.78ppm respectively. The contents of allicin and diallyl disulfide of onion samples treated as the whole, sliced and crushed forms increased with the progress of vacuum freeze drying. The degree of increase was different in each onion sample form prepared by vacuum freeze drying(p<0.05). The specific activity of alliinase in raw onions was 7.536 units/mg protein. The activity in onion samples treated as the whole, sliced and crushed forms decreased with the progress of vacuum freeze drying. The activity in the whole onion prepared by the vacuum freeze drying for 8 hrs reduced to 5.516 units/mg protein with 73.2% remaining and to 3.304 units/mg protein with 43.8% remaining for 36 hrs. The activity in the sliced onion prepared by the vacuum freeze drying for 36 hrs reduced to 2.366 units/mg protein with 31.4% remaining and the activity in the crushed onion prepared by the vacuum freeze drying for 36 hrs reduced to 2.232 units/mg protein with 29.6% remaining. The alliinase in onion sample treated as the whole form showed the highest remaining activity during the vacuum freeze drying.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.376-380
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• 1994

마늘의 alliinase를 ammonium sulfate 분획과 hydroxylapatite chromatography, concanavalin A-Sepharose affinity chromatography에 의해 정제하여, 23% 의 회수율과 7.6배 정제도를 나타내었다(specific activity 116.6 units/mg). SDS-polyacrylamide gel electrophoresis에서 단일 band를 나타내므로 순수한 aliinase 로 추측되며 이 효소의 분자량은 42K 로 추정된다. 기질로서 S-ethyl-L-cysteine sulfoxide를 사용한 이 효소의 $V_max$값은 2.27${\mu}$monl/mg.min이고 $K_m$은 1O mM이다 . 정제효소의 optimum pH는 6.5 phosphate buffer이며, 40$^{\circ}C$에서 최대활성을 나타내었다. Activation energy value($E^*$)는 4.6Kcal/mole로 추정된다.

• Journal of Crop Science and Biotechnology
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• v.10 no.1
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• pp.19-26
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• 2007

Glutathione S-transferases(GSTs, EC 2.5.1.18), glyoxalase-I(EC 4.4.1.5) and alliin lyase(alliinase, EC 4.4.1.4) are important enzyme systems in plant bodies. The first two are mainly detoxifying enzymes that utilize glutathione(GSH) in the defense mechanism, and the last one is mainly involved in secondary metabolism and relevant to sulfur compounds derived from GSH. The activities of the three enzymes have been investigated in soluble extracts of vegetable crops, including pumpkin, cabbage, broccoli, radish, carrot, potato, sweet potato, mungbean, and onion. GST activities were detected in all of the vegetables, and the extract of onion bulb exhibited the highest specific activity(648 nmol/min/mgP). The putative GSTs of most of the vegetables were found to be induced by ethanol. The activities of GSTs in onion bulb were found to be markedly inhibited by S-hexyl glutathione and were also inhibited by S-butyl glutathione and S-propyl glutathione. The anti-CmGSTF1 antiserum recognized a thick band for putative onion GST. The estimated glyoxalase-I activity level was also high in onion bulb(4540 nmol/min/mgP), indicating that the thick band detected by Western blot analysis might result from partial recognition of glyoxalase-I by the antiserum. The specific activities for glyoxalase-I were moderate in radish and carrot, and the extracts of other vegetables had rather low levels of activities. The extract of onion also showed the highest specific activity level for alliinase(2069nmol pyruvate/mgP). The extracts of other vegetables also had alliinase activities, although the estimated values were much lower than that of onion.

• Food Science and Biotechnology
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• v.15 no.6
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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.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.655-660
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• 2012

The purpose of this study is to evaluate pungency-related factors of field garlic (FG) and rice paddy garlic (RG) from Youncheon province. Allicin, alliin, and S-allyl-L-cysteine (SAC) contents were analyzed by HPLC. In addition, activities of alliinase, GTPase (${\gamma}$-glutamyltranspeptidase), and pyruvate content of garlic were measured. The moisture content of RG (65.86%) was higher than that of FG (63.34%). However, crude lipid, crude protein, crude ash, and carbohydrate contents of RG were lower than those of FG. The alliin contents of FG and RG were 8.97 and 8.22 mg/g, respectively. The allicin content of FG (2.83 mg/g) was higher than that of RG (2.22 mg/g). Further, SAC content of FG (1.74 mg/g) was higher than that of RG (0.104 mg/g). Alliinase activities of FG and RG were similar, whereas the GTPase activity of FG was higher than that of RG. These results show that the stronger pungency of FG is due to the higher amount of alliin and SAC as well as the higher activity of GTPase compared to RG.

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.291-292
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• 2008