• Horticultural Science & Technology
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• v.28 no.3
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• pp.387-393
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• 2010

The free sugar content and related enzymes of four different parts, inner, outer, stylar end and stem end, of 'Changhowon Hwangdo' peach ($Prunus$ $persica$, L. Batsch) fruit were compared from August to September in 2006, i.e., from 120 to 150 days after full bloom (DAFB). The soluble solids content (SSC) of stylar end was the highest among the four fruit parts at 150 DAFB. Changes of free sugar content were similar to that of SSC in the four parts. The starch content at the stylar end was the highest at 120 DAFB, while all the other parts showed low starch contents at 150 DAFB. The free sugar composition of peach changed during fruit development. The sucrose was low at 120 DAFB and increased gradually in all parts of peach fruit. On the contrary glucose, fructose and sorbitol decreased with fruit development. The free sugar contents and related enzymes activities were investigated during fruit development. The rapid increase of sucrose contents during fruit development was more affected by sucrose synthase than sucrose phosphate synthase. Activity of SS in the four fruit parts increased continuously over the fruit development period, but activity of acid invertase showed a downward trend. This study found that the free sugar content was affected by enzyme activity for the synthesis or the cleavage. However, it was very difficult to explain sugar accumulation of peach segments with related-enzymes.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.25-31
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• 1999

The purpose of study was to test the hypothesis that preschool children who experienced nursing caries have high dft index and caries activity in primary dentition. One thousand and seventy-five preschool children from 4 to 6 years old were examined for their caries experience and salivary invertase activity by Resazurin Disc Test. Nursing caries group was identified by the criteria of having more decayed and filled teeth among the upper incisors than among the upper molars. The prevalence of nursing caries was 15.8%. The dft index of nursing caries group was significantly higher than that of the other groups except the rampant caries group(P<0.01). The Resazurin Disc Test score of nursing caries group was significantly higher than that of the other groups(P<0.01) and there was no difference between nursing caries group and rampant caries group. Therefore, it is recommended that children who experienced nursing caries should be incorporated in the caries prevention program through the primary and mixed dentition.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.35-42
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• 1983

This study was conducted to know changes in chemical components and some enzyme activity on tobacco leaves of NC2326 and Hyangchio (Nicotiana tabacum L. ) by different curing methods. The activity of $\alpha$, $\beta$-amylase and invertase of flue-cured tobacco variety NC2326 were higher than that of sun-cured variety Hyangchio. And the peak of all of enzyme activity in both varieties showed at about 60 hours (at color fixing stage) and 6 days (yellowing stage) after start of flue-curing and sun-curing, respectively. The peak time of reducing sugar content were same with the maximum enzyme activity during curing process in both varieties. During both curing process, the content of starch was greatly reduced and there was a corresponding increase in reducing sugars. Increase in total alkaloids content continued during flue-curing process in both varieties, but during sun-curing process total alkaloids content of NC 2326 were Increased whereas those of Hyangchio were decreased markedly.

• Korean Journal of Microbiology
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• v.13 no.3
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• pp.85-90
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• 1975

Crude cellulases freshly prepared from cultures of Aspergillus niger, Prnicillum motatum, Trichoderma vride 16273 and Trichoderma viride 16374 were assayed on 4 different substrates including Na-CMC, cellulose powder, starch and sucrose. Enzyme prepared from A. niger contained highly active hydrolytic enzymes of the 4 substrates assayed. P. notatum [yielded relatively lower amount of cellulase but the extracts were also highly reactive on starch and sucrose. Trichoderma viride 16274 yielded very little cellulase and invertase, but the extracts showed a high degree of amylase activity. Trichoderma viride 16374, however, yielded collulase comparable to that of Penicillium notatum, but lower activities of amylase and invertase were seen. Commercial cellulases prepared from Penicillium notatum (cellulase[K]) and Trichoderma viride(cellulase[J]) indicated enzyme activities closely parallel to the crude enzymes freshly prepared from fungus cultures. The optimum pH's of cellulolytic activities of cellulase[K] and cellulase[J] were 4.0 and 5.0 respectively. The optimum temperatures of the cellulolytic activities of cellulase[K] and cellualse[J] were 4.0 and 5.0 respectively. The optimum temperatures of the cellulolytic activities of cellulase [K] and cellulase [J] were $60{\circ}C$ and $50{\circ}C$ respectively. Assuming the average molecular weight of Na-CMC is about 115,000, the Km values of cellulase [K] and cellulase[J] were found to be $3.3{\times}10^{-5}/nM$ and $3.3{\times}10^{-4}/nM$ respectively.

• Korean journal of food and cookery science
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• v.14 no.2
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• pp.182-187
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• 1998

The changes in weight, reducing sugar content, sugar composition and enzyme activities (${\beta}$-amylase and invertase) of sweet potato were studied with three kinds of cooking methods, microwave oven, gas oven, and steaming. The weights of sweet potato cooked by microwave oven and gas oven were decreased with increasing cooking time, whereas that of steaming was increased with cooking time. Reducing sugar content of sweet potato cooked by microwave oven was increased till 40 seconds, but decreased thereafter. In the cooking methods using gas oven and steaming, reducing sugar content were increased with cooking time. And reducing sugar content were 334.60 mg/g and 381.29 mg/g, respectively at 100$^{\circ}C$ of cold point in sweet potato cooked by gas oven and steaming. Raw sweet potato consisted of fructose (1.56 mg/g), glucose (1.79 mg/g), sucrose (5.58 mg/g), and maltose (2.22 mg/g). The contents of fructose, glucose, and sucrose were decreased during cooking process. But maltose content was increased with cooking time. Especially, maltose contents were 24.81 mg/g and 28.10 mg/g at 100$^{\circ}C$ of cold point in sweet potato cooked by gas oven and steaming. The activities of ${\beta}$-amylase and invertase were decreased with cooking time. Microwave oven-cooked sweet potato did not show on invertase activity.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.283-290
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• 1979

Partially purified ${\beta}-fructosidase$ (inulase) from Kluyveromyces fragilis was immobilized on Tygon tube and aminoethyl-cellulose, respectively and both preparations were characterized. Silanization of Tygon tube in chloroform at $65^{\circ}C$ and treatment with 10 % glutaraldehyde were critical for the immobilization of inulase on Tygon tube, while 2 % glutaraldehyde was effective for the immobilization on aminoethyl-cellulose. The derivative of Tygon tube showed 11.5 units of inulase activity per g of dried matrix with retention of 22.5 % of original activity against inulin, whereas one of aminoethyl-cellulose showed 39.3 units per g of dired matrix with 53.4 % of retention. Studies of enzyme stability, pH and temperature dependences, and $K_m$ values are presented for inulase and invertase activities of both immobilized enzymes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1731-1736
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• 2014

The quality characteristics, enzyme activity, and antioxidative activity of fermented wild grass juices were investigated during fermentation and ripening for 6 months. Fermented wild grass juice was prepared from wild grasses (Oenothera biennis, Portulaca oleracea, and Rhus verniciflua) and sugar. Wild grasses and sugar mixed at the same ratio (1:1, w/w) and ripened at $20^{\circ}C$ for 3 months after fermentation for 3 months at $20^{\circ}C$. The $^{\circ}Bx$ of all fermented wild grass juices (FWGJ) decreased during fermentation. The pH of all FWGJ decreased gradually during fermentation and did not show any significant difference during ripening. Viscosity of FWGJ increased during fermentation but decreased during ripening periods in all tested samples. Total viable cell of FWGJ decreased after fermentation for 1 month, whereas lactic acid bacteria were not detected during fermentation. Enzyme activity was lower than 1 unit during fermentation and ripening period in all tested FWGJ samples. Enzyme activity of commercial FWGJ (Acanthopanax sessiliflorum, Oenanthe javanica, Plantago asiatica L., Platycodon grandiflorum, Orostachys japonicus A.) showed lower activity of 1 unit following invertase, cellulase, and amylase activity.

• Applied Biological Chemistry
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• v.8
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• pp.75-80
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• 1967

In order to investigate the change of enzyme activities during the fermentation of tobacco leaves, whole and cut leaves were treated for twenty days at $30^{\circ}C$ and $39^{\circ}C$ by the normal procedure and inoculation of yeast, respectively, and the activity of several enzymes was measured at proper intervals. 1) Alpha-amylase activity was steadily decreased with the progress of fermentation. 2) Invertase and catalase activities were steadily decreased until the mid of the period, and then increased again toward the end of the fermentation. The latter enzyme activity showed more marked change than the former. 3) Most of the polyphenol oxidase activity were decreased abruptly in the early stage of the fermentation, and thereafter leveled down slowly. 4) Peroxidase activity was detected throughout the fermentation but no remarkable change was observed. 5) Protease activtty was not detected through the fermentation period.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.551-558
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• 1992

The extracellular endoinulase from Streptomyces sp. 556 was purified and characterized, The culture broth was fractionated by ammonium sulfate saturation followed by DEAE-cellulose column chromatography and 5ephadex G-200 gel filtration, The ultimately purified fraction revealed a single band in 7.5% polyacrylamide gel electropherogram. The purified enzyme showed the maximal activity at pH 5.5-6.0 and $50^{\circ}C$, but lost 93% of inulase activity after 30 min incubation at $55^{\circ}C$ . The essen.tial amino acid residue for catalytic activity appeared to be tryptophan. This endo inulase was activated by $Mn^{2+}$, whereas inactivated by $Ag^{+}$, $Hg^{+}$, $Cu^{2+}$, $Zn^{2+}$, $Fe^{3+}$ and $Mo^{6+}$ EDTA and 8-hydroxyquinoline inhibited the enzyme so that the enzyme was considered to be a metalloenzyme. The Km value for inulin was 0.287 mM, and no invertase or $\alpha$-glucosidase activity was found in the enzyme.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.4
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• pp.473-479
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• 2012

In this study, increased alcohol decomposition efficacy (ADH) of Hoveina dulcis extract by Carbohydrate-Hydrolyzing Enzymes was investigated. Carbohydrate decomposition enzymes such as Maxinvert (Invertase), Optidex L-400 (Glucoamylase) and Rohament CL (Cellulase & Pectinase) were added to Hoveina dulcis extract at different concentrations (0.01, 0.05, 0.1, 0.5 and 1%) for 48 hrs, after which samples were taken every 6 hrs for determination of ADH activity. As the enzyme concentration became higher, ADH activity also increased. Especially, the addition of 1% Rohament CL increased enzyme activity to 76% at 30 hrs incubation, after which the increase in activity stopped. In the rat and human body experiment, enzymatic decomposition of Hovenia dulcis extract by addition of 1% Rohament CL was also effective in decreasing serum alcohol concentration and respiration. Especially, in the early stage after alcohol consumption, the efficacy of enzyme treatment of Hovenia dulcis extract was more effective. These results show that if the glycoside forms of active compounds such as flavonols in Hovenia dulcis extract are converted into aglycone forms, alcohol decomposition capability can be enhanced.