• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.1-5
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• 1982

An invertase from Korean ginseng (Panax ginseng C. A. Mayer) was purified by means of DEAE-cellulose column chromatography and gel-filtration through Sephadex G-75. The homogeneity of the purified invertase was proved by polyacrylamide gel disc electrophoresis. The enzyme was separated into two subunits by SDS-polyacrylamide gel electrophoresis, showing its molecular weights as 48,000. The enzyme preparation showed a characteristic protein UV-spectra.

• Journal of Plant Biology
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• v.35 no.4
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• pp.333-338
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• 1992

Ginkgo (Ginkgo biloba L.) seeds were analyzed to determine the level of soluble sugars and insoluble starch during germination. Also the activities of the hydrolytic enzymes such as amylase, invertase and phosphatase were compared. As amylase activity was sharply increased, significant decline of starch was observed in the female gametophyte and increase of soluble sugars occurred concurrently. Invertase activity was gradually increased in cotyledon and radicle, while it was very low in dry seeds. In addition, phosphatase activity was variable only in radicle, and acid phosphatase showed higher activity than alkaline phosphatase.hatase.

• Journal of Ecology and Environment
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• v.46 no.2
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• pp.136-143
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• 2022

Background: In northern Thailand, the longan flower is the principal nectar source for honey production. Microorganisms play a critical function in the agricultural ecology. The morphological characteristics of fungal species found in longan pollen were studied. Aspergillus spp. were found to be invertase-producing strains and were employed in the longan syrup production process. The purpose of this study was to evaluate the effects of invertase-added longan syrup on the adult honey bee population numbers that were fed by this syrup for 16 weeks. Results: Different fungal species were found in longan pollen samples. Aspergillus was the main genus, with three predominant sections: Nigri, Flavi, and Terrei. Other isolated species were Trichoderma spp., Rhizopus spp., Neurospora spp., Chaetomium spp., Fusarium spp. and Penicillium spp. However, Aspergillus spp. is the only fungal species that produces the enzyme invertase. The invertase-producing strains belonging to the Aspergillus section Nigri were found to be A. niger LP5 with an optimum activity at pH 6.0 and 60℃. When A. niger LP5 invertase was used for longan syrup processing, the highest levels of glucose (3.45%) and fructose (2.08%) were found in invertase added longan syrup (C), while fresh (A) and boiled longan syrup (B) had lower contents of both sugars. The sucrose content was detected in (A) at 4.25%, while (B) and (C) were at 4.02% and 3.08%, respectively. An appropriate amount of sugar to feed and maintain the honey bee population was considered. The data showed no statistically significant differences between the two selected forms of longan syrup compared to the sugar syrup examined by the adult honey bee population. Conclusions: The main species of isolated fungi from longan pollen were Aspergillus spp. The discovery of an invertase-producing strain of A. niger LP5 has enabled its application for enzyme utilization in the invert sugar preparation process. The adult worker bee populations fed by longan syrup from both boiled and invertase-added sources showed an increasing trend. Artificial syrup made from longan fruit to feed honey bees when natural food sources are limited can be applied.

• Journal of Life Science
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• v.11 no.1
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• pp.14-21
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• 2001

To investigate the changes of carbohydrate metabolism in the senescing leaves of Zea mays during dark-induced senescence, the changes in the contents of reducing sugar, sucrose and starch as well as the activities of sucrose synthase, three isozymes of invertase, and ${\alpha}$-amylase were measured. In the senescing leaves, the content of reducing sugars temporarily increased at 4 d and rapidly decreased thereafter, whereas sucrose contents gradually decreased thereafter, whereas sucrose contents gradually decreased until 3 d of senscence and significantly decreased thereafter. The activities of intracellular invertases such as soluble acid and alkaline formed gradually enhanced until 4 d of leaf senescence and significantly declined thereafter. The extracellular invertase activity showed no significant changes during leaf senescence. The deactivation of sucrose synthase was observed within 3 d of leaf senscence. On the other hand, the starch contents gradually declined during 2 d of leaf senescence, and showed a temporary increase at 3 d, which is similar to the pattern of sucrose synthase activity., These results imply that sucrose in the senescing leaves. The major enzymes which correlated to the breakdown of sucrose during dark-induced senescence were soluble acid and alkaline invertases, not sucrose and ABA accelerated leaf senescence by inducing the accumulation of reducing sugar. These result, therefore, that leaf senescence may be mediated by the temporary quantitative changes of reducing sugar induced by the activation of intracellualr inveertases.

• Journal of Applied Biological Chemistry
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• v.50 no.4
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• pp.196-201
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• 2007

An intracellular invertase was purified to homogeneity from the cell extract of an alkalophilic and thermophilic Bacillus sp. TA-11, which was classified as a new species belonging to Bacillus cereus based on chemotaxanomic and phylogenetic analyses. The purified enzyme with a recovery of 26.6% was determined to be a monomeric protein with a molecular weight of 23 kDa by SDS-PAGE and 26 kDa by gel filtration. The maximum enzyme activity was observed at pH 7.0 and $50^{\circ}C$, and the purified enzyme was stable at the pH range of 5.0 to 8.0 and below $60^{\circ}C$. $K_m$ and $V_{max}$ values of the enzyme for sucrose were 370 mM and 3.0 ${\mu}M$ per min, respectively. The enzyme activity was significantly inhibited by bivalent metal ions ($Hg^{2+}$, $Cd^{2+}$ and $Cu^{2+}$) and sugars (glucose and fructose).

• Horticultural Science & Technology
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• v.34 no.6
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• pp.898-911
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• 2016

Sugars play many important roles in plant metabolism and directly influence fruit quality. The effects of two edible coatings, 2% calcium chloride and 1% pullulan, on sugar metabolism in postharvest Huangguan pear fruit were investigated during cold storage. The respiration rate, sugar content and composition, sucrose metabolism enzyme activities [acid invertase (AIV), neutral invertase (NI), sucrose synthase (SS), and sucrose phosphate synthase (SPS)] and expression of the AIV gene were analyzed during storage at $0^{\circ}C$ for 210 days. Coating treatments slowed the decrease of sucrose and hexose, the respiration rate, and the activities of AIV, NI, SS and SPS, thus maintaining high total soluble solids (TSS) and titratable acid (TA) contents in the fruit. There were no significant differences in AIV expression or activity between the treated and control groups of fruits. Both of the coatings could inhibit the activities of sucrose-cleaving enzymes, thus slowing the decrease of sugar content and maintaining high fruit quality during cold storage.

• Journal of Microbiology and Biotechnology
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• v.25 no.6
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• pp.837-844
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• 2015

Carob waste is a useful raw material for the second-generation ethanol because 50% of its dry weight is sucrose, glucose, and fructose. To optimize the process, we have studied the influence of the initial concentration of sugars on the fermentation performance of Saccharomyces cerevisiae. With initial sugar concentrations (S₀ ) of 20 g/l, the yeasts were derepressed and the ethanol produced during the exponential phase was consumed in a diauxic phase. The rate of ethanol consumption decreased with increasing S₀ and disappeared at 250 g/l when the Crabtree effect was complete and almost all the sugar consumed was transformed into ethanol with a yield factor of 0.42 g/g. Sucrose hydrolysis was delayed at high S₀ because of glucose repression of invertase synthesis, which was triggered at concentrations above 40 g/l. At S₀ higher than 250 g/l, even when glucose had been exhausted, sucrose was hydrolyzed very slowly, probably due to an inhibition at this low water activity. Although with lower metabolic rates and longer times of fermentation, 250 g/l is considered the optimal initial concentration because it avoids the diauxic consumption of ethanol and maintains enough invertase activity to consume all the sucrose, and also avoids the inhibitions due to lower water activities at higher S₀ .

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.680-685
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• 1994

Total nitrogen content, proline, free amino acids, sugars, invertase and diastase activities in native bee-honey (NBH) and foregin bee-honey (FBH) harvested from our different areas of Kangwon , Korea were determined. The total nitrogen contents of NBH and FBH were 0.077$\pm$0.033mg% and 0.055$\pm$0.022mg%, respectively. Proline content in NBH was 42$\pm$10mg% and waqs found to be much lower than that in FHB. Phenylalanine and proline were major free amino acids both in NBH and FBH . The content of total free amino acid in FBH were twice as much as that in NBH , however isomaltose content in NBH were almost two times more than that in FBH. Other sugars including fructose, glucos , sucrose and maltose were also analyzed. No differences were found between NBH and FBH in invertase activities, but comparing to these of FBH ,lower values of diastase activity in NBH were observed.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.271.2-271
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• 1995

No Abstract, See Full Text

• Applied Biological Chemistry
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• v.27 no.1
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• pp.45-51
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• 1984

Kluyveromyces marxinus LG contains an inulase activity which is inducible by growth on inulin. The highest enzyme activity obtained at the initial stage of stationary phase of growth curve. The partially purified inulase hydrolyzed inulin, sucrose and raffinose. This enzyme showed the maximal activity at pH 4.0 and temperature of $55^{\circ}C$ for inulin and sucrose. It was also markedly inhibited by $Hg^{++}\;and\;Ag^{+}$ but not EDTA. This inulase was charaterized as a undo type which contains invertase activity and Km values for inulin and sucrose were $1.2{\times}10^{-2}M\;and\;1.3{\times}10^{-4}M$, respectively.