• Journal of the Korean Applied Science and Technology
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• v.15 no.3
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• pp.61-66
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• 1998

Cyclodextrin are obtained from starch by enzymatic degradation. The three best characterize forms are ${\alpha}$, ${\beta}$, ${\gamma}$ cyclodextrin consisting of 6, 7, and 8 D-glucose units, respectively. Each of the glucose units are in the rigid C1 chair conformation and are linked by ${\alpha}$ 1,4 bonds. This geometry gives the cyclodextrin the shape of a hollow truncated cone with the wider side formed by the secondary 2- and 3-hydroxy groups and the narrower side by the primary 6-hydroxy group. The most characteristics property of the cyclodextrin is their ability to form inclusion complexes with a wide range of guest moleculars. We syntheses per-6-substituted ${\beta}$-cyclodextrin derivatives and investigate structures, spectrospcopic properties. The substituted materials are piperidine, piperazin, morphorine. The synthetic compound showed a good solubility than natural ${\beta}$ cyclodextrin in organic solvents such as methylene chloride, methanol, ethanol, etc.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1544-1549
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• 2008

MhMTS and MhMTH are trehalose ($\alpha$-D-glucopyranosyl-[1,1]-$\alpha$-D-glucopyranose) biosynthesis genes of the thermophilic microorganism Metallosphaera hakonensis, and encode a maltooligosyltrehalose synthase (MhMTS) and a maltooligosyltrehalose trehalohydrolase (MhMTH), respectively. In this study, the two genes were fused in-frame in a recombinant DNA, and expressed in Escherichia coli to produce a bifunctional fusion enzyme, MhMTSH. Similar to the two-step reactions with MhMTS and MhMTH, the fusion enzyme catalyzed the sequential reactions on maltopentaose, maltotriosyltrehalose formation, and following hydrolysis, producing trehalose and maltotriose. Optimum conditions for the fusion enzyme-catalyzed trehalose synthesis were around $70^{\circ}C$ and pH 5.0-6.0. The MhMTSH fusion enzyme exhibited a high degree of thermostability, retaining 80% of the activity when pre-incubated at $70^{\circ}C$ for 48 h. The stability was gradually abolished by incubating the fusion enzyme at above $80^{\circ}C$. The MhMTSH fusion enzyme was active on various sizes of maltooligosaccharides, extending its substrate specificity to soluble starch, the most abundant natural source of trehalose production.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.357-364
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• 1995

A biochemical genetic study on blood enzyme/protein systems in some breeds/crosses of sheep in Malaysia was carried out using horizontal starch gel electrophoresis. Blood samples were collected from 435 sheep, representing 8 breeds/crosses. These included 5 wool sheep breeds (Thai Longtail, wiltshire, Suffolk, Dorsimal and cMBLx), 1 hair sheep breed (Barbados Blackbelly) and 2 hybrids between wool sheep and hair sheep (Cameroon ${\times}$ Thai Longtail and Bali Bali ${\times}$ Malin). Twenty loci systems were examined. Of these, ten ($HB{\beta}$, ALB, TF, XP, CAT, DIA1, EsA, GPI, ME and NP) exhibited genetic variation whereas the other ten (AAT, CA, DIA2, ${\alpha}GLO$, ${\alpha}GLU$, LDH, MDH, PEP[leu-gly-gly], 6PGD and SOD) were monomorphic. The allelic frequencies which were obtained in 10 polymorphic markers are assessed and compared with the results obtained by previous workers. The estimations of inbreeding coefficient, intrabreed variation and breed relationships have been critically discussed and are used to reveal some important recommendations.

• Journal of environmental and Sanitary engineering
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• v.24 no.1
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• pp.40-46
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• 2009

The enzyme expressed from strain L-49 was 2.01 times higher than that of original strain. Strain L-49 can grow on culture plate with $50{\mu}g/mL$ ampicillin. The synthesis of $\alpha$-amylase was greatly suppressed when strain L-49 was grown on monosaccharide such as glucose and polysaccharide at the same time cell concentration was low. Amylase production was enhanced when the bacterium was grown on starch and dextrin. Among different nitrogen sources tried, yeast extract was found to be the best followed by panpeptone, peptone, meat extract, bean meal, and corn steep liquor. The average rate of enzyme production was enhanced for 3~4 times in fermentation time from 24h to 44h. The sugar uptake rate has also increased. Low oxygen supply rate enhanced the rate of strain propagation but depressed the enzyme production. Hence it is benefit to obtain high enzyme activity that agitation speed maintained not lower than 400r/min and aeration rate maintained greater than 1:1vvm.

• Preventive Nutrition and Food Science
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• v.11 no.4
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• pp.318-322
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• 2006

The objective of this experiment was to investigate the effect of extrusion of ginseng roots in twin screw extruder on susceptibility of ginseng starch toward hydrolysis by ${\alpha}-amylase$ BAN 480L (Novozyme, Denmark) and cellulase Celluclast 150L and saccharification by amyloglucosidase AMG-E (Novozyme, Denmark). The extrusion was conducted at 22% and 30% moisture contents of feed at screw speed 300 rpm. Barrel temperature at zone 1 was adjusted at $100^{\circ}C$ and $120^{\circ}C$. The results showed that extrusion process improved the ginseng ${\alpha}-amylase$ susceptibility as compared to traditionally dried ginseng (white and red ginseng). Reducing sugar of hydrolyzed extruded samples was 2,500% of its initial concentration, whereas the reducing sugar of hydrolyzed non-extruded sample was only 200% of its initial concentration. However, addition of cellulase during liquefaction lowered the saccharification yield of both non-extruded and extruded samples as well.

• 보존과학연구
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• s.13
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• pp.81-95
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• 1992

The old books which have been colored to brown spots were analyzed chemically to compare with white part. The original raw materials were paper mulberry (Broussonetia Kazine) and woodpulp. White part contained58.8%($\alpha$-37.2%,$\beta$-8.6%, $\gamma$-12.7%)cellulose, 21.7% hemicellulose, 19.8% lignin,4.4% pentosan and brown sopt part contained 49.1%($\alpha$-19.8%, $\beta$-14.5%,$\gamma$-14.8%) cellulose, 27.1% hemicellulose, 23.8% lignin, 4.8% pentosan. Both of brown spot and white parts contained starch without protein. The pH was 4.9 in brown and 5.0 in white part respecitively. The brown spot parts were more solidified than white parts according to SEM observation. Difference of organiccompinent in brown part came from white part were 2-hydroxy-benzaldehydeand phenol.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.121-125
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• 1997

A total of 437 landraces of rice from Vietnam were analyzed for total seed protein by SDS-PAGE and phenol reaction. The different types of glutelin $\alpha$ subunits were detected. The level of wx protein with 60kDa molecular weight was divided into 3 groups, corresponding to non-glutinous, intermediate and glutinous starch types. Based on the variation in seed storage protein and wx protein, landraces were classified into 7 groups. Frequency distribution of types A and B of glutelin $\alpha$ subunits changed with the latitude at which rice landraces were collected. Geographical cline for phenol reaction was detected.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.340-344
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• 2002

A gene, npl, encoding neopullulanase from Paenibacillus sp. KCTC 8848P was cloned and expressed in Escherichia coli. It consisted of an open reading frame of 1,530 bp for a protein that consisted of 510 amino acids with a molecular weight of 58,075 Da. The deduced amino acid sequence of the neopullulanase gene had $92\%$ identity with the neopullulanase of Bacillus polymyxa. The npl gene was also expressed in Saccharomyces cerevisiae secreting Schwanniomyces occidentalis glucoamylase (GAM1) under the control of the yeast actin gene (ACT1) promoter. Secretion of the neopullulanase was directed by the yeast mating pheromone ${\alpha}$ -factor ($MF{\alpha}1$) prepro region. Enzyme assays confirmed that co-expression of npl and GAM1 enhanced starch and pullulan degradation by S. cerevisiae.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.289-293
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• 1997

The effects of different types of additives(sucrose fatty acid ester(SE), oligosaccharide and alum) on 40% nonwaxy rice starch gels stored at $20{\pm}1^{\circ}C$ were investigated by ${\alpha}-amylase-iodine$ method, X-ray diffractometry and differential scanning calorimetry. The addition of SE retarded the retrogradation of gels throughout storage period and the antistaling effect of SE was increased with increasing concentration. Oligosaccharide(0.1%) inhibited the retrogradation, but oligosaccharide(0.1% or 0.5%) retarded the retrogradation at early stage of storage, and stimulated the retrogradation after 3 days. Alum of 0.1% level retarded the retrogradation, but 0.3% level activated the retrogradation after 24 hours and 0.5% level did after 12 hours. The effect of additives on the retrogradation of rice starch gels showed the different tendencies at the level of additives. On 0.1% level, the effect of those was similar but on 0.5%, the degree of retardation increased in order of oligosaccharide, SE1170, alum, no addition for up to 2 days of storage and SE1170, no addition, oligosaccharide, alum for 3 days of storage.

• Nutrition Research and Practice
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• v.1 no.3
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• pp.184-188
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• 2007

The major goal in the treatment of diabetes mellitus is to achieve near-normal glycemic control. To optimize both fasting blood glucose and postprandial glucose levels is important in keeping blood glucose levels as close to normal as possible. ${\alpha}-Glucosidase$ is the enzyme that digests dietary carbohydrate, and inhibition of this enzyme could suppress postprandial hyperglycemia. The purpose of this study was to test the inhibitory activity of methanol extract of Euonymus alatus on ${\alpha}-glucosidase$ in vitro and in vivo to evaluate its possible use as an anti-diabetic agent. Yeast ${\alpha}-glucosidase$ inhibitory activities of methanol extract of E. alatus were measured at concentrations of 0.50, 0.25, 0.10, and 0.05 mg/ml. The ability of E. alatus to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without E. alatus extract (500 mg/kg) was administered to diabetic rats by gastric intubation after an overnight fast. Plasma glucose levels were measured at 30, 60, 90, 120, 180, and 240 min. Plasma glucose levels were expressed in increments from baseline, and incremental areas under the response curve were calculated. Extract of E. alatus, which had an $IC_{50}$ value of 0.272 mg/ml, inhibited yeast ${\alpha}-glucosidase$ activity in a concentration-dependent manner. A single oral dose of E. alatus extract significantly inhibited increases in blood glucose levels at 60 and 90 min (p<0.05) and significantly decreased incremental response areas under the glycemic response curve (p<0.05). These results suggest that E. alatus has an antihyperglycemic effect by inhibiting ${\alpha}-glucosidase$ activity in this animal model of diabetes mellitus.