• Food Science and Biotechnology
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• 제17권6호
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• pp.1349-1351
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• 2008

This study examined the effects of temperature, D-psicose concentration, pH, and various amino acids on the Maillard browning reaction of D-psicose and glycine mixture and compared browning color intensity with those of other sugars, such as sucrose, D-glucose, D-fructose, and D-tagatose. When D-psicose (0.1 M) and glycine (0.1 M) mixture was heated at $70-100^{\circ}C$ for 5 hr, the absorbance at 420 nm increased with increasing reaction temperature and time. The Hunter a, b values, and color difference (${\Delta}E$) increased with increasing D-psicose concentration and pH within the range of pH 3-7 except at pH 6, while the L value decreased. The rate of Maillard browning reaction was in order of D-tagatose>D-psicose $\fallingdotseq$ D-fructose>D-glucose>sucrose. The browning color intensity of the D-psicose-basic and non-polar amino acids mixtures was higher than that of the D-psicose-acidic amino acids.

• Journal of Microbiology and Biotechnology
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• 제18권6호
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• pp.1136-1140
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• 2008

The Rhodopseudomonas palustris KUGB306 hemA gene codes for 5-aminolevulinic acid (ALA) synthase. This enzyme catalyzes the condensation of glycine and succinyl-CoA to yield ALA in the presence of the cofactor pyridoxal 5'-phosphate. The R. palustris KUGB306 hemA gene in the pGEX-KG vector system was transformed into Escherichia coli BL21. The effects of physiological factors on the extracellular production of ALA by the recombinant E. coli were studied. Terrific Broth (TB) medium resulted in significantly higher cell growth and ALA production than did Luria-Bertani (LB) medium. ALA production was significantly enhanced by the addition of succinate together with glycine in the medium. Maximal ALA production (2.5 g/l) was observed upon the addition of D-glucose as an ALA dehydratase inhibitor in the late-log culture phase. Based on the results obtained from the shake-flask cultures, fermentation was carried out using the recombinant E. coli in TB medium, with the initial addition of 90 mM glycine and 120 mM succinate, and the addition of 45 mM D-glucose in the late-log phase. The extracellular production of ALA was also influenced by the pH of the culture broth. We maintained a pH of 6.5 in the fermenter throughout the culture process, achieving the maximal levels of extracellular ALA production (5.15 g/l, 39.3 mM).

• 한국식품영양학회지
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• 제25권2호
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• pp.246-252
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• 2012

After a mixed carbohydrate diet, inhibition of ${\alpha}$-amylase and ${\alpha}$-glucosidase involved in the digestion and absorption of carbohydrates can significantly decrease the postprandial increase of blood glucose level. In the course of screening these useful enzyme inhibitors, we selected five kinds of bean, using an in-vitro enzyme inhibition assay method. To evaluate the effect of germination process on the functionality of the bean, we investigated the inhibitory activities of the water extracts of non-germinated bean and germinated bean against ${\alpha}$-amylase and ${\alpha}$-glucosidase, relevant to postprandial hyperglycemia. We also investigated the oxygen radical absorbance capacity(ORAC), total phenolics content, and postprandial blood glucose lowering effect in rats(Sprague-Dawley rat model). Most germinated beans showed significantly higher ${\alpha}$-glucosidase inhibitory activity, compared with non-germinated beans. Among germinated beans, Glycine max had the highest ${\alpha}$-glucosidase inhibitory activity(53.3%). The water extract of germinated Phaseolus vulgaris L. had the highest ${\alpha}$-amylase inhibitory activity(95.1%), followed by Glycine max(58.7%), and Glycine max L. Merr(54.1%). Furthermore, the five germinated beans also showed high antioxidant activities in ORAC assay. Results suggested that the germination process may improve and enhance the anti-hyperglycemia potential and antioxidant activity of the bean.

• 생명과학회지
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• 제22권11호
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• pp.1451-1455
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• 2012

다양한 아미노산과 당을 $90^{\circ}C$에서 반응시켜 생성한 마이얄반응 생성물(Maillard reaction product)은 쑥갓에서 추출한 폴리페놀산화효소(polyphenol Oxidase, PPO)를 강하게 저해하였다. 글리신(glycine)과 포도당을 함유한 반응물으로부터 MRP의 생성은 $90^{\circ}C$에서 반응시간에 따라 직선적으로 증가하였으나 글리신과 포도당의 양은 상대적으로 감소하였다. 반응액에서 MRP의 증가함에 따라 반응액은 쑥갓 PPO활성을 비례적으로 강하게 저해하였다. 실험에 사용한 아미노산과 당중에서 글루타민과 자일로스를 아미노산과 당으로 이용했을 경우에 생성된 MRP가 쑥갓 PPO의 활성에 강한 저해제로 작용하였다. 카테콜을 기질로 사용한 쑥갓 PPO의 마이클레스 상수(Michaelis Menten constant)는 22.0 mM이었으며, MRP는 쑥갓 PPO의 비경쟁적 저해제로 작용하였다.

• 한국식품영양과학회지
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• 제28권2호
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• pp.285-291
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• 1999

To confirm the food quality of Urechis unicinctus which have been favored as a special raw seafood in southern area in Korea, the chemical composition of Urechis unicinctus and those glycoprotein were studied. Freeze dried Urechis unicinctus was composed of more than 70% of crude protein and 15% of total carbohydrate. The amino acids such as glycine(18.69%), glutamic acid(12.50%) and aspartic acid(9.37%) were noted as major components of total amino acids. The predominant free amino acids were alanine(32.98%), glycine(27.50%), asparagine(19.65%) and taurine(8.29%), and the sum of them were more than 88% to total free amino acids, so they may cause unique taste of Urechis unicinctus with sweetness. As the basis of sugar composition analysis, 56.35% of glucose and 30.49% of N acetylglucosamine were contained respectively, and they might also play an important role in a sweet taste. The leading carbohydrate moiety of glycoprotein from Urechis unicinctus was identified as glucose and N acetylglucosamine similarly to raw muscle, and they occupied more than 50% of total sugar content. Fucose(18.32%) and D glucuronic acid(12.31%) also detected in higher levels com pared to raw muscle. The total amino acid profile of glycoprotein showed a similar trend to raw muscle protein but glycine was detected a significantly lower than that in raw muscle. The glycoprotein from Urechis unicinctus was composed of 4 kinds of subunits, i.e. 25kDa, 20kDa, 18kDa and 12.5kDa of molecular weights through the SDS polyacrylamide gel electrophoresis. On the basis of the IR spectrum of absorptions appeared in 1,240cm-1 and 850cm-1, the glycoprotein had sulfate groups.

• 한국수산과학회지
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• 제19권1호
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• pp.36-44
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• 1986

glucose-glycin 계로부터 조제한 비투석성 melanoidin에 ozone을 작용시켜서, melanoidin의 탈색 및 분해생성을 검토하였다. 그 결과, ozone에 의한 melanoidin의 탈색률은 10분 반응으로 $84\%$, 90분 반응으로 $97\%$에 각각 달하였고, 평균분자량 7,000의 말처리 Melanoidin이 40분의 ozone 처리에 의하여 분자량 3000까지 저분자화하였다. 또한, 적외선흡수스펙트럼의 결과, ozone 처리에 의하여 $1,290\;cm^{-1}$의 흡수가 소실됨과 동시에 $1,720\;cm^{-1}$의 흡수가 새롭게 출현하였고, 산가수분해에 의하여 $1,620\;cm^{-1}$ 흡수가 완전히 소실되었다. 한편 melanoidin을 ozone 처리함으로써 얻어진 에테르 가용성획분 중의 주요분해생성물은 butanedioic acid, glycolic acid 및 2-hydroxybutanoic acid 등이었고, 수용성획분중의 주요분해생성물은 glycine으로서, ozone 처리만으로 $1.05\%$, 산가수분해만으로는 $1.95\%$ 생성되는데 반하여, ozone 처리후 산가수분해함으로써 melanoidin 당 $5.75\%$ 생성되었다. 이 결과와 적외선흡수 스펙트럼의 결과를 함께 비교하여 보면, 일부의 glycine 이 melanoidin 중에 amide 상태로 결합되어 있음은 물론, ozone 처리에 따라 amide 결합이 새로이 형성된다고 생각된다.

• 한국동물학회지
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• 제7권2호
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• pp.25-36
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• 1964

The present paper deals with the comparative study on phylogenic difference in the patterns of energy metabolism of brain slices of several vertebrate species by measuring oxygen consumptionwith glucose-6-phosphate, glucose-1-phosphate, glyceraldehyde-3-phosphate or glutamate as respiratory substrate employing Warburg's manometric method, by determination of the utilization rate of glucose using glucose-1-C14 by analyzing patterns of free amino acid distribution , and by histochemical determination using glucose-1-C14 by analyzing patterns of free amino acid distribution acid distribution , and by histochemical determination of glycogen contents. 1. Glucose enhances the oxygen consumption of brain slices of animals belinging to reptile, aves and mammalia while it shows a tendency to decrease that of animals belonging to pisces and amphibia. 2. Glucose-6--phosphate increase oxygen consumption more than glucose in every species examined, while glucose-1-phosphate and glyceraldehyde-3-phosphate increase that of Rana nigromaculata only . In general m, it appears that phosphosugars are more effective as a respiratory substrate to those species which have less endogenous respiration than to those having larger endogenous respiration. 3. Similar patterns of free amino acid distribution and the relative amount are found among the species and in every species examined glutamic acid is detected in the larges amount . ${\gamma}$-Amino butyric acid, glycine, alanine and aspartic acid are found in every species. 4. Ophicephalus showed less oxygen consumption than endogenous respiration when glutamate was added to the medium. When sodium fluoride was added, the oxygen consumption was some what increased . Such phenomenon wasnot found in the frog. 5. The result of histochemcial analysis of the brain showed that glycogen was abundantly present in the fish , amphibia , and especially in the reptile and that no distinctive grains of glycogen were found in the bird and mammal . From these facts, it may be supposed that anaerobic glycolysis as energy source dominates in fish and amphibia and aerobic respiration through the oxidation of glucose dominates in bird and mamal , the reptile occupying transitional position between these two categories. The way of obtaining energy for brain activity by the oxidation of glucose supplied from the circulating blood is seemed to be first acquired by reptile and the function is completed both in aves and mammal.

• Journal of Plant Biology
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• 제37권2호
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• pp.195-201
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• 1994

Methylglyoxal bis-(guanylhydrazone)[MGBG]과 polyamine이 부정근 형성시 탄수화물 대사에 미치는 영향을 알아보고자 대두 자엽 절편을 이용하여 $5{\times}10^{-6}\;M\;NAA와\;5{\times}10^{-7}M$ kinetin으로 조성한 부정근 형성구에 $10^{-3}M$ MGBG와 이 MGBG에 $10^{-5}M$의 putrescine, spermidine 및 spermine을 각각 혼합 처리하여 전분 및 수용성당의 함량 변화와 함께 관련 효소의 활성도 변화를 조사하였다. 전분 및 maltose와 sucrose 함량은 대조구가 가장 낮았으며, MGBG를 포함하는 모든 처리구가 대체로 높게 나타났다. Glucose 함량 변화는 시차는 있으나 대조구와 spermine 동시 처리구가 유사하여 증가 후 감소하였으며 MGBG 처리구는 감소 후 증가하였다. Amylase의 활성은 대조구와 MGBG 처리구에서 유사한 양상을 나타내어 지속적으로 증가하였으며 maltase의 활성은 대조구에서 가장 높았고 invertase의 활성은 큰 변화가 없었다.

• 한국미생물·생명공학회지
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• 제13권3호
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• pp.285-287
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• 1985

To investigate effective constituents of the many taste components in ordinary Korean soy sauce, we analyzed free amino acids, organic acids, free sugars and saline as taste components in ordinary Korean soy sauce, and determined sensory score of the ordinary Korean soy sauce taste with 45 persons of the trained pannels. The relationships between original data transformed with variables and sensory score of the ordinary Korean soy sauce were analyzed by stepwise multiple regression analysis. Eighty five percents of the ordinary Korean soy sauce taste is affected by twenty one kinds (Isoleucine, Leucine, Valine, NaCl, Lactic acid, Alanine, Phenylalanine, Tartaric acid, Sugar(\ulcorner), Proline, Malic acid, Glycine, Tryptophan, Arginine, Glutaric acid, Maltose, Histidine, Glucose, Fructose and Serine) of the taste components by stepwise multiple regression analysis of original data. Eighty one percents of the ordinary Korean soy sance taste is affected by sixteen kinds (Lactic acid, NaCl, Fumaric.Succinic acid, Tyrosine, Tartaric acid, Glycine, Malonic acid, Malic acid, Tryptophan, Glutaric acid, Methionine, Histidine, Cysteine, Maltose, Fructose and (Glutamic acid) of the taste components by stepwise multiple frgression analysis of original data transformed with square root. Eighty five percents of the ordinary Korean soy sauce taste is affected by nineteen kinds (Fumaric.Succinic acid, Lactic acid, Phenylalanine, NaCl, Tyrosine, Sugar(\ulcorner), Tartaric acid, Leucine, Glutaric acid, Methionine, Glycine, Tryptophan, Histidine, Proline, Cysteine, Glutamic acid, Maltose, Threonine and Oxalic acid) of the taste components by stepwise multiple regression analysis of original data transformed with logarithm.

• 한국식품조리과학회지
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• 제16권6호
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• pp.629-639
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• 2000

10$0^{\circ}C$ 이상에서 당단독, 당과 유기산 또는 유기산염의 caramel 갈색화 반응과 당과 아미노산의 Maillard 갈색 화 반응의 갈색화 물질의 항산화성을 측정하고자 0.1M 의 xylose(XY), glucose(GL), sucrose(SU)를 단독으로, 0.1M glucose에 0.02M의 citric acid를 혼합한 glucose-citric acid(GLCA), 0.02M의 sodium citrate를 혼합한 glucose-sodium citrate(GLSC)와 0.1M의 glycine을 혼합한 glucose-glycine(GLGC)을 80, 120 및 14$0^{\circ}C$에서 12, 24시간 가열하여 얻은 갈색화 반응 생성물의 수소공여능(HDA)에 의한 항산화성을 측정하였으며 이들의 무수 ethanol 추출물의 옥배유 기질에 대한 항산화 효과를 측정하여 기존 항산화제(TBHQ, TOCO)와 비교, 고찰한 결과는 다음과 같았다. 1. Caramel 갈색화 반응 생성물의 수소공여능(HDA)에 의한 환원력은 갈색화 반응온도 및 시간의 경과에 따라 대체적으로 증가되었으며 갈색도가 큰 반응계일수로 환원력이 크게 나타났다. XY, GL, SU, GLCA, GLSC 및 GLGC 갈색화 반응액의 수소공여능은 8$0^{\circ}C$에서 24시간 반응 후 각각 0.290, 0.299, 0.281, 0.301, 0.362 및 0,387로 그 크기는 GLGC > GLSC > GLCA > GL > XY > SU 순이었다. 12$0^{\circ}C$에서 24시간 반응 후의 GLCA와 GLGC에서 갈색도의 증가와는 달리 HDA는 오히려 낮아졌으며, 14$0^{\circ}C$ 에서는 대부분의 갈색화 반응액의 HDA는 온도가 상승함에 따라 높아졌지만 GLCA와 GLGC의 HDA는 낮아져서 각각 0.275 및 0.305로 된 반면에 GLSC의 HDA는 계속 증가하여 0.543으로 가장 높은 것으로 나타났다. 이 때의 HDA는 GLSC > SU > GL > GLGC > XY > GLCA 순이었다. 2. 갈색화 반응 생성물의 무수 ethanol 추출물을 첨가한 옥배유의 항산화 효과는 TBHQ에는 못미치나 TOCO 보다는 우수한 항산화력을 나타내는 것도 있었다. 8$0^{\circ}C$에서 24시간 진행된 갈색화 반응 생성물의 경우는 TBHQ > GLCA > GLGC > TOCO > SU > XY > GL > GLSC > control의 순으로 8$0^{\circ}C$에서는 갈색화 반응 중간생성물은 모두 항산화 효과를 나타내었으며 GLCA의 항산화 효과는 TBHQ 보다는 크게 떨어지나 GLGC, TOCO보다는 높은 항산화력을 보여주었다. 또한 120및 14$0^{\circ}C$에서 24시간 진행된 갈색화 반응생성물의 항산화 효과는 SU, GLCA에서만 보였으며 이들의 항산화 효과는 Maillard형 갈색화 반응액인 GLGC의 항산화 효과 보다 높았다. 그 크기는 TBHQ > SU > TOCO > GLCA > control > GLSC > GLGC > XY > GL의 순으로 80, 120및 14$0^{\circ}C$에서의 갈색화 반응 생성물의 항산화성은 8$0^{\circ}C$에서 가장 좋은 것으로 나타났다. 이상으로 볼 때 각종 갈색화 반응 생성물의 수소공여능에 의한 환원력과 항산화 효과의 관계는 환원력이 증가함에 따라 항산화 효과는 증가하지 않고 감소하여 갈색화 반응물의 항산화 효과와 환원력 사이에는 뚜렷한 상관관계가 없는 것 같았다.