• Food Science and Preservation
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• v.13 no.5
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• pp.563-568
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• 2006

The properties of mung bean were investigated depending on hydrolysis condition. The results showed that enzyme treatments (${\alpha}$-amylase and protease each at 0.1% (w/w)) by varying hydrolysis temperature showed better properties than non-pretense treatment (control group). The treatment with 0.08% ${\alpha}$-amylase was best for optimum hydrolysis of mung bean starch The treatment using a mixture of 0.08% (w/w) ${\alpha}$-amylase and 0.12% (w/w) protease was best for optimum hydrolysis of meg bean protein. The effects of Hydrolysis time of mung bean showed that the optimum time was 60 and 90 min and there fore the optimum time was set at 60 min. These result showed that the best hydrolysis conditions of mung bean were the treatment at $60^{\circ}C$ for 60 min using a mixture of 0.08%(w/w) ${\alpha}$-amylase and 0.12% (w/w) pretense, with the sugar level shown at $5.8^{\circ}Brix$, reducing sugar at 2,022.13 mg% and crude protein at 7,666.17 mg%.

• Applied Biological Chemistry
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• v.43 no.1
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• pp.18-23
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• 2000

stract : Fourteen varieties of glutinous rices were examined on amylopectin fine structure and physicochemical properties of starch granules. The amylopectin chain length distribution and short chain/long chain ratio were investigated by enzymatic treatments followed by high-performance size-exclusion chromatographic separation. Chain length distribution profiles of the isoamylase-debranched amylopectins showed distinct patterns according to varieties. Beongok showed the highest short chain/long chain ratio, while TP2579A1 showed the lowest one. Sharebyeo-152-1-B showed the highest hydrolysis rate to 15% $H_2SO_4$, while Sandong 47 showed the lowest one. Fourteen varieties of rice starch granules showed A-type pattern on X-ray diffractograms. Non-gelitinized starch granules from Keochang 1 and Beongok had almost 100% hydrolysed by glucoamylase for 3 hrs at $370^{\circ}C$.

• Applied Biological Chemistry
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• v.3
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• pp.9-15
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• 1962

1) Among 8 strains of Rhizopus and 7 of Aspergillus species investigated for their producibility of saccharifying amylase, Rhizopus delemar ND 1 and Aspergillus usamii mut. shirousamii were selected as having high saccharifying activity. 2). Since Rh. delemar ND 1 shows high saccharifying activity and slight transglucosidase activity, it likely seems suitable for the production of starch-sugar by enzymic saccharification. Asp. usamii mut. shirousamii exerts low saccharifying but moderate transglucesidase activity and is considered to be usable in producing sugar-syrup with particular flavor and taste. 3). Using the saccharogenic enzyme from Rh. delemar ND 1, a prelimimary trial was done to obtain purified glucose powders.

• KSBB Journal
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• v.18 no.5
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• pp.363-370
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• 2003

A filamentous fungus, strain FM04 producing amylase was isolated from rotten yam peels and potatoes. The favorable conditions of cultivation factors such as, temperature, pH, and agitation speed of strain FM04 were 28∼30$^{\circ}C$, 5.0∼6.0, and 100 rpm, respectively. Starch was the best carbon source in the amylase production. Therefore, food wastes containing lots of starch were employed as the carbon source of the cultivation for the economical amylase production. 5.2 U/ml of amylase was obtained In the cultivation using 1 % (w/v) of food wastes. The amylase showed the highest activity at enzyme reaction conditions of 60$^{\circ}C$ and pH 4.5 and showed 90% of residual activity after the reaction at 50$^{\circ}C$ for 2 days. In the enzymatic hydrolysis reaction using 20% (w/v) of food wastes and 2.5 U/ml of amylase, 72.6 g/l of reducing sugar was obtained at the reaction condition of 50$^{\circ}C$, pH 4.5 for 2 days.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.255-260
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• 1996

증편반죽의 발효에 따른 해면상의 조직(망상구조)형성능의 mechanism을 조사하기 위하여 반죽의 구성성분의 경시적 물성 및 효소(diastase 및 protease) 활성의 변화, 구성 전분 분획의 glucose chain length 변화 및 1% SDS에 의해서 용출되는 단백질 분획의 변화에 대해서 검토하였다. 발효가 진행됨에 따라 증편반죽의 pH는 감소한 반면 점성 및 부피는 발효경과 10시간가지 증가하다가 그 이후로는 약간 감소하는 경향을 보였다. 발효의 진행과 더불어 diastase의 활성은 증가하였으며, 쌀전분 분획 중 amylose의 함량은 약간 감소하였다. 그리고 전분분자의 $\alpha-1,6-glucoside$ 결합을 isoamylase(debranching enzyme)로 가수분해시킨 후 Sephadex G-75를 이용한 chromatogram 분석에 의하면 쌀가루 전분 분획과 증편반죽 전분 분획의 glucose chain length 분포는 거의 유사하지만 발효가 진행됨에 따라 중합도가 낮은 부분이 우선적으로 diastase의 작용을 받은 것이라고 생각되어진다. 한편, 발효가 진행된에 따라 protease의 활성은 증가하고 있었음에도 불구하고 증편반죽의 당에 의한 단백질 분획의 고분자화가 Suprose CL-12 column chromatogram 상에서 관찰되었는데, 이것은 아마도 발효과정 중 증편반죽에 공존하는 미생물들의 발효산물인 당질(gum질)을 매개로 한 단백질 분자의 회합에 의한 결과라고 생각되어진다. 따라서 이러한 결과를 미루어 볼 때 증편반죽의 망상구조 형성능은 발효과정 중 일어나는 당과 단백질간의 상호작용에 의한 결과라 생각되어진다.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.858-862
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• 2008

The Simultaneous Saccharification and Fermentation(SSF) of ethanol production from potato starch studied with respect to growth pH, temperature, substrate concentration. The glucoamylase and Saccharomyceses cerevisiae have a capacity to carry out a single stage SSF process for ethanol production. The characteristics, termed as starch hydrolysis, accumulation of glucose, ethanol production and biomass formation, were affected with variation in pH, temperature and starch concentration. The maximum ethanol concentration of 12.9g/l was obtained using a starch concentration 30g/l, which represent an ethanol yield of 86%. The optimum conditions for the maximum ethanol yield were found to be a temperature of 38, pH of 4.0 and fermentation time of 18hr. Thus by using the control composite design, it is possible to determine the accurate values of the fermentation parameters where maximum production of ethanol occurs.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.352-358
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• 2002

An amylase that hydrolyzes starch into maltopentaose as a main product was found in the culture supernatant of a strain of Bacillus megaterium KSM B-404 isolated from local soil. The enzyme was purified 129-fold by ammonium sulfate precipitation, DEAE-Toyopearl and Superdex 75 HR 10/30 column using a FPLC system. The molecular weight of the amylase was determined as about 68 kDa by using SDS-PAGE. Optimum pH and temperature of amylase were found to be $50^{\circ}C$ and pH 6.0~7.0, respectively. The enzyme was stable up to $60^{\circ}C$ by addition of $Ca^{2+}$ and its pH stability was in the range of 6.0~10.0. The activity of enzyme was inhibited by $Cu^{2+}$ $Hg^{2+}$ , and $Fe^{3+}$ and maintained by $Ca^{2+}$ and $Mg^{2+}$ . EDTA and pCMB also showed inhibitory effect to the enzyme. TLC and HPLC analysis of the products of the enzyme reaction showed the presence of maltopentaose(52%), maltotriose (25%), maltose (11%), glucose, and maltotetraose in the starch hydrolysates.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.391-398
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• 1999

Enzymatic hydrolysis of crushed ginger was carried out to increase the yield of ginger extract, and the quality of the extract was investigated. The first extract was obtained by pressing crushed ginger, and the second extract by pressing ginger pomace hydrolyzed with $\alpha$-amylase at $90^{\circ}C$ for 1 hr. Oleoresin was extracted from the residue of enzymatic hydrolysis with 90% ethyl alcohol. The first extract, second extract and oleoresin were mixed to obtain the final ginger extract. The yield of final extract was increased by 276% on the solid base of the fresh ginger extract. The final ginger extract contained less crude fiber, starch and free amino acids (62, 48 and 40%, respectively), but contained more free sugar (270%) compared to fresh ginger extract.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.507-512
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• 2017

The physicochemical properties of maize starch sonicated at various amplitudes (100, 200, and 300 W) and times (10, 30, and 50 min) were examined. The amount of enzyme-susceptible starch increased marginally after sonication. Sonication increased the amount of oil absorbed in the starch although the degree of oil absorption decreased with an extension of the sonication time, implied that different types and extent of damages occurred. Scanning electron microscopy revealed that ultrasound sonication did not form pores on the surfaces, but caused damages such as depression and erosion. Pasting viscosity of starch decreased with an increase in the severity of sonication conditions because of the weakened polymer network. X-ray diffraction suggested that the crystalline domains in starch were not susceptible to sonication and were more resistance to degradation. Sonicated starch formed more pin-holes on the surfaces in the initial glucoamylase reaction; subsequently, as the reaction proceeded, porous starch with enlarged pores was formed and finally, disrupted granular fragments were observed.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.389-394
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• 1992

Effect of dry-heat treatment $(130{\sim}220^{\circ}C)$ on properties of corn starch was investigated. No significant changes of surface color and swelling power were observed. Blue value, water-binding capacity, solubility and degree of hydrolysis by acid or glucoamylase were increased; however, intrinsic viscosity and crystallinity were decreased as heating temperature was raised. Noticeable changes occurred between $170{\sim}190^{\circ}C$.