• Journal of Microbiology and Biotechnology
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• v.28 no.9
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• pp.1447-1456
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• 2018

The amylosucrase encoding gene from Deinococcus geothermalis DSM 11300 (DgAS) was codon-optimized and expressed in Escherichia coli. The enzyme was employed for biosynthesis of three different dihydroxybenzene glucosides using sucrose as the source of glucose moiety. The reaction parameters, including temperature, pH, and donor (sucrose) and acceptor substrate concentrations, were optimized to increase the production yield. This study demonstrates the highest ever reported molar yield of hydroquinone glucosides 325.6 mM (88.6 g/l), resorcinol glucosides 130.2 mM (35.4 g/l) and catechol glucosides 284.4 mM (77.4 g/l) when 400 mM hydroquinone, 200 mM resorcinol and 300 mM catechol, respectively, were used as an acceptor substrate. Furthermore, the use of commercially available amyloglucosidase at the end of the transglycosylation reaction minimized the gluco-oligosaccharides, thereby enhancing the target productivity of mono-glucosides. Moreover, the immobilized DgAS on Amicogen LKZ118 beads led to a 278.4 mM (75.8 g/l), 108.8 mM (29.6 g/l) and 211.2 mM (57.5 g/l) final concentration of mono-glycosylated product of hydroquinone, catechol and resorcinol at 35 cycles, respectively, when the same substrate concentration was used as mentioned above. The percent yield of the total glycosides of hydroquinone and catechol varied from 85% to 90% during 35 cycles of reactions in an immobilized system, however, in case of resorcinol the yield was in between 65% to 70%. The immobilized DgAS enhanced the efficiency of the glycosylation reaction and is therefore considered effective for industrial application.

• KSBB Journal
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• v.27 no.3
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• pp.137-144
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• 2012

Among various pretreatment processes for bioethanol production, extrusion pretreatment, one of cheap and simple process was investigated to efficiently produce fermentable sugars from micro alga, Chlorella sp. The biomass was pretreated in a single screw extruder at five different barrel temperatures of 45, 50, 55, 60 and $65^{\circ}C$, respectively with five screw rotation speed of 10, 50, 100, 150 and 200 rpm. The pretreated biomass was reacted with two different hydrolyzing enzymes of cellulase and amyloglucosidase since the biomass contained different types of carbohydrates, compared to cellulose of agricultural by-products such wheat and corn stovers, etc. In general, higher glucose conversion yield was obtained as 13.24 (%, w/w) at $55^{\circ}C$ of barrel temperature and 100 rpm of screw speed conditions. In treating 5 FPU/glucan of cellulase and 150 Unit/mL of amyloglucosidase, ca. 64% of cellulose and 40% of polysaccharides in the micro alga were converted into glucose, which was higher yields than those from other reported data without applying an extrusion process. 84% of the fermentable sugars obtained from the hyrolyzing processes were fermented into ethanol in considering 50% of theoretical maximum fermentation yield of the yeast. These results implied that high speed extrusion could be suitable as a pretreatment process for the production of bioethanol from Chlorella sp.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.618-628
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• 2000

The indigestible dextrin I was prepared by hydrolyzing pyrodextrin with thermostable ${\alpha}-amylase$. The mean values of indigestible fraction and dieatry fiber of indigestible dextrin I prepared from yellow dextrin were 50.0% and 25.0%, respectively. Also the indigestible dextrin II was prepared by removing low molecular weight saccharides containing glucose with ethanol from enzyme hydrolysate of pyrodextrins. Over 80% of glucose and maltose in initial enzyme hydrolysate were removed, therefore the indigestible fraction and dietary fiber of the indigestible dextrins increased. The indigestible dextrin from ethanol precipitate of enzyme hydrolysate of yellow dextrin by ${\alpha}-amylase$ and amyloglucosidase showed a higher contents of indigestible fraction and dietary fiber than ethanol precipitates by any other enzyme combination, and its mean values were 83.6% and 62.8%, respectively. Consequently, it was found that the indigestible dextrins which are resistant to starch-hydrolysing enzyme can be easily prepared from pyrodextrin, and presumed that they can perform physiological functions as soluble dietary fiber.

• KSBB Journal
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• v.5 no.4
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• pp.329-334
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• 1990

In an attempt to develop a novel process for ethanol production from starch, a simultaneous saccharification and fermentation (SSF) process using Zymomonas mobilis and amyloglucosidase (AMG) was studied in continuous modes. Compared with a conventional cylindrical column type of fermentor, the tapered column type of fermentor was found to be superior in terms of reactor performance for ethanol fermentation. The tapered columm fermentor packed with coimmobilized Z. mobilis and AMG alleviated the problems which were associated with CO2 evolution and provided a significantly better flow pattern for both liquid and gas phases in the fermentor without channelling. However, the fluidized bed type of tapered column fermentor using flocculent strain of Z. mobiles and immobilized AMG showed lower productivity (5.2g/1/h) than that of packed bed type of tapered column fermentor(9.2g/l/h).

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.858-862
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• 2001

The purpose of this research was to investigate the effects of nondigestible oligosaccharides (NDO) from red ginseng marc on the growth of Bifidobacterium spp. Red ginseng marc, a fibrous byproduct of ginseng extract from processing, was destarched by ${\alpha}$-amylase and amyloglucosidase treatment, and then treated with a commercial pectinase to produce NDO. The bifidogenic effects of NDO on B. adolescentis, B. animalis, B. breve, and B. longum were investigated in vitro. NDO significantly promoted the growth of Bifidobacterium spp. The growth, decrease of pH, and organic acid formation (acetate, lactate, formate) were markedly different among the species. B. adolescentis showed the best growth and produced the greatest amount of organic acids. When NDO was used as a carbon source in the cocultivation of Bifidobacterium spp. and Clostridium perfringens, the growth of Bifidobacterium spp. was not influenced by the existence of Cl. perfringens. The result strongly suggested that NDO from red ginseng marc could be used as a potential bifidogenic source.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1039-1045
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• 2003

Functional healthy drinks were processed with freeze dried powders of ethanol extract from of defatted safflower (Carthamus tinctorious L.) seed cake and some useful components of the drinks were investigated. Yield of freeze dried powder was the highest as 8.42% when it extracted with 60% ethanol (60% EFDP). Each drink contained 0.02% of freeze dried powder and ranged 10.6∼13.8% of soluble solid, 2.90∼3.68 of pH, 0.10∼0.83% of titratable acidity. ‘L’ value of drink-I (DSD-I) was the highest as 94.82$\pm$2.45, ‘b’ and ‘a’ value of drink-V (DSD-V) was highest as 27.15-2.65 and 28.67$\pm$2.69, respectively. Major free sugars of drink were 6015.3∼7918.2 mg% of glucose and 1511.4∼2091.0 mg% of sucrose. The content of citric acid was the highest as 179.2∼981.3 mg%. The content of total phenol in 60% EFDP was 99.17 mg% and that of drink-II(DSD-II) and DSD-V was 307.84 mg% and 224.06 mg%, respectively. Total flavonoid was contained as 50.29 mg% in 80% ethanol extract (80% EFDP) and 125.20 mg% in DSD-V. N-[2-(5-hydroxy-1H-indol-3-yl) ethyl] ferulamide (serotonin-I) was determined as high as 18.81 ppm in 80% EFDP and ranged 2.42∼2.89 ppm in drinks. N-[2-(5-hydroxy-lH-indol-3yl)ethyl]-p-coumaramide (serotonin-II) was determined as 30.17 ppm in 80% EFDP and ranged 3.79∼4.59 ppm in drinks. Acacetin, flavonoid compound were 9.83 ppm in amyloglucosidase hydrosis + 60% ethanol extract (A + 60% EFDP) and ranged 0.98∼1.26 ppm in drinks. Electron donating ability (EDA, %) was measured and compared with 100 ppm BHA as chemical antioxidant. EDA was 93.97$\pm$2.21% in A+60% EFDP, 94.79$\pm$2.26% in DSD-I, 94.69$\pm$1.37% in DSD-II, and 93.83$\pm$1.49% in BHA. DSD-II added with hot water extract solution from Korean ginseng and safflower yellow pigment recorded the highest sensory score.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.617-624
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• 2002

Health drinks were prepared with freeze dried powder of 60% ethanol extract (60% EFDP), 60% ethanol extract after hydrolysis with amyloglucosidase (60% AEFDP) and 80% ethanol extract (80% EFDP) from roasted safflower seed. Quality characteristics and antioxidative properties were investigated. Yield of freeze dried powders were ranged in $4.67%{\sim}5.62%$. Brix, pH and titratable acidity of safflower drinks were ranged in $11.4{\sim}14.2%$, $2.83{\sim}3.34$ and $0.09{\sim}0.91%$, respectively. Content of total phenolic compounds was much more in 80% EFDP (117 mg/g) and safflower drink-I (SD-I, 440 ppm) than others. Content of total flavonoid was observed in higher level in 60% EFDP (49 mg/g) and safflower drink-V (SD-V, 138 ppm) than others. Antioxidant compounds such as N-[2-(5-hydroxy-1H-indol-3-yl)ethyl]ferulamide(serotonin-I) and N-[2-(5-hydroxy-1H-indol-3yl)ethyl]-p-coumaramide(serotonin-II) exhibited higher contents of 21.09 ppm, 33.56 ppm in 60% EFDP and of 3.83 ppm, 5.81 ppm in safflower drink-II (SD-II) than others. Content of acacetin was much more in 80% EFDP (13.53 ppm) and safflower drink-IV (SD-IV, 1.14 ppm) than others. From the DPPH test to measure antioxidant activity, it was shown that 80% EFDP and SD-I have stronger scavenging activities of 94.58% and 94.88%, respectively, while BHA standard solution does 93.88%. Among drinks, SD-II was revealed to have highest level on overall acceptance, color and flavor through sensory evaluation. These results induced that safflower seed can be used as natural antioxidant and functional food material.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.22-27
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• 1993

Crude ${\beta}-glucan$ extracted from Barley was purified by stepwide enzyme treatment with thermostable ${\alpha}-amylase$, amyloglucosidase and protease. The thermal properties of Barley ${\beta}-glucan$ were investigated by Differential Scanning Calorimetry. Three endotherms have been observed on DSC thermograms of Barley ${\beta}-glucan$. The first endotherm which produced the gelatinization phenomena commonly observed in Barley ${\beta}-glucan$ became the focus of this study. The temperature range and the enthalpy of gelation exhibited maximum values with increasing concentration of Barley ${\beta}-glucan$. Gelating Barley ${\beta}-glucan$ registered an enthalpy of approximately 0.23 cal/g and exhibited onset temperature (To), peak temperature (Tp) and conclusion temperature (Tc) of $48.8^{\circ}C,\;61.2^{\circ}C\;and\;78.5^{\circ}C$ respectively. The temperature and enthalpy of gelatinizing Barley ${\beta}-glucan$ at both alkali and acid conditions were lower than those at pH 7. With salt present, the Tp and Tc of gelating Barley ${\beta}-glucan$ produced lower temperatures than in conditions where salt was absent, and the enthalpy abruptly decreased. However, increasing salt concentrations did not affect the gelation temperature and the enthalpy of Barley ${\beta}-glucan$. The 'true melting' temperature of Barley ${\beta}-glucan$ was near $184^{\circ}C$ and the melting enthalpy was approximately 34.6 cal/g. The Barley ${\beta}-glucan$ decomposition temperature was in the range of $316^{\circ}C{\sim}346^{\circ}C$.

• Journal of Mushroom
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• v.11 no.4
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• pp.261-268
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• 2013

This study was conducted to investigate the physiological activities and nutrition contents of Gonji No.10 and Solhyang, the strains of Neolentinus lepideus. In nutritional contents of two strains of N. lepideus, the content of free sugars and sugar alcohols and total polyphenol were more in Gonji No.10 than Solhyang. The total contents of amino acids and ${\beta}$-glucan in Solhyang are more than those in Gonji No.10. Solhyang also showed higher DPPH radical scavenging activity than Gonji No.10. In particular, hot water extract of Solhyang has higher inhibitory activity of ${\alpha}$-amylase and ${\alpha}$-amyloglucosidase while Gonji No.10 has higher anti-inflammatiory effect than Solhyang. But, they have similar effects on nitrite scavenging activity.

• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.350-355
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• 2012

This study investigated the physiological effects of three species of Auricularia known as Auricularia polytricha (JNM21001), Auricularia auricula-judae black (JNM21002), and Auricularia auricula-judae brown (JNM21012). In the ORAC assay, Auricularia spp. showed antioxidant activities in the order of JNM21001>JNM21012>JNM21002. All Auricularia spp. strongly inhibited the action of ${\alpha}$-amyloglucosidase up to 60%. In order to further test in vivo anti-obesity effects, high fat diet induced ICR obese mice fed a diet containing 20% fat were used. All Auricularia spp. supplementation during high fat diet feeding significantly reduced body weight gain, epididymal fat pads weight, and lowered the food efficiency ratio compared to the high fat control (HFC) group. In particular, the group fed with JNM21012 had a lower average daily body weight gain of 0.45 g/day, demonstrating similar levels to the normal diet fed group. The group fed with JNM21012 significantly reduced lowered serum triglycerides (42%), total cholesterol (81%), and LDL-cholesterol level (66%) compared with the HFC group.