• Applied Biological Chemistry
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• v.39 no.2
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• pp.99-103
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• 1996

A bacterial strain producing a novel endo-inulinase, hydrolysing inulin into oligosaccharides was isolated from soil and identified as Arthrobacter sp. S37 The enzyme production was induced by inulin and jerusalem artichoke extract. The maximum enzyme production was obtained with medium containing 1.5% jerusalem artichoke extract, 1.0% yeast extract, $0.5%\;NaNO_3,\;0.05%\;MgSO_4{\cdot}7H_2O,\;0.05%\;KCl,\;0.0016%\;FeCl_3{\cdot}6H_2O\;and\;0.05%\;KH_2PO_4$. The optimum temperature and pH for the enzyme production were $30^{\circ}C$ and 8.0, respectively. Under the optimum condition, the enzyme activity in the culture broth reached at maximum, 10.8 units/ml after cultivation for 24 hours.

• Korean Journal of Medicinal Crop Science
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• v.19 no.4
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• pp.257-263
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• 2011

This study investigated the changes of antioxidant activity and ${\alpha}$-glucosidase inhibitory effect of Jerusalem artichoke (Helianthus tuberosus) 100% methanol extracts by various heat treatment. The contents of total phenolic and flavonoid compounds in methanol extract tended to increased gradually with the rise of temperature to 180$^{\circ}C$. The maximum yield of gallic acid (51.52 ${\pm}$ 2.17mg/g extract weight) and quercetin (13.39 ${\pm}$ 0.03mg/g extract weight) were obtained with extraction temperature of 180$^{\circ}C$ for 120min. In addition, the improving extraction efficiency resulted in the increased biological activities, such as electronic donation ability (EDA, 90.36${\pm}$ 0.57%), reducing power (Abs 1.14) and ${\alpha}$-glucosidase inhibitory effect (92.14 ${\pm}$ 1.14%). Overall, the results of this study indicate that the optimum conditions for the extraction process were an extraction temperature at 180$^{\circ}C$ for 120 min, and will provide the basis for future research on the improving extraction yield of phenolic and flavonoid compounds.

• KSBB Journal
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• v.5 no.1
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• pp.75-80
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• 1990

The investigations of specific growth rate, specific alcohol production rate, cell yield, alcohol yield of K. marxianus LG were performed according to the sugar concentrations, 50, 80, 110, 190, and 250g/l of extracted solution of Jerusalem Artichoke. The functipnal relationship between specific growth rate, specific alcohol production rate, and alcohol concentrations were devoted study to. In case of low concentration of alcohol, the fuctions were linear relationships. But in the region of high concentration of alcohol, they expressed the exponential relationships. The growth rate of K. marxianus was prohibited at higher than 50g/l of alcohol concentrations regardless of concentration of residual sugar. Cell and alcohol yield showed the maximum values around 25g/l of alcohol concentraton without being related to initial sugar concentrations.

• The Plant Pathology Journal
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• v.37 no.5
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• pp.428-436
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• 2021

Stem rot is a serious disease in Jerusalem artichoke (JA). To reduce the impact of this disease on yield and quality farmers often use fungicides, but this control method can be expensive and leave chemical residues. The objective of this study was to evaluate the efficacy of two biological control agents, Trichoderma harzianum T9 and Bacillus firmus BSR032 for control of Sclerotium rolfsii under field conditions. Four accessions of JA (HEL246, HEL65, JA47, and JA12) were treated or notreated with T. harzianum T9 and B. firmus BSR032 in a 4 × 2 × 2 factorial experiment in two fields (environments), one unfertilized and one fertilized. Plants were inoculated with S. rolfsii and disease was evaluated at 3-day intervals for 46 days. T. harzianum T9 and B. firmus BSR032 reduced disease incidence by 48% and 49%, respectively, whereas T. harzianum T9 + B. firmus BSR032 reduced disease incidence by 37%. The efficacy of T. harzianum T9 and B. firmus BSR032 for control of S. rolfsii was dependent on environments and genotypes. The expression of host plant resistance also depended on the environment. However, HEL246 showed consistently low disease incidence and severity index in both environments (fertilized and unfertilized). Individually, T. harzianum T9, B. firmus BSR032, or host plant resistance control stem rot caused by S. rolfsii in JA. However, no combination of these treatments provided more effective control than each alone.

• Journal of Life Science
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• v.28 no.1
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• pp.26-36
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• 2018

This study was performed to identify the antioxidant and ${\alpha}$-glucosidase inhibitory activities of water and 70% ethanol extracts of the three following herbs: G. procumbens, M. charantia, and C. longa. In addition, the antioxidant and antidiabetic activities of five types of Jerusalem artichoke composites (JA1 - 5), which were prepared by adding ethanol extracts of several herbs to Jerusalem artichoke concentrate, were studied and compared. The results showed that the total phenol and flavonoid contents of the ethanol extracts were higher than those of the water extracts. The DPPH and ABTS radical scavenging activities and reducing power depended on the total phenol and flavonoid contents. The antioxidant activities of ethanol extracts from G. procumbens and C. longa were comparable. Moreover, the ${\alpha}$-glucosidase inhibitory activity of the ethanol extracts ($2,000{\mu}g/ml$) from each herb was found to be over 50%. In contrast, the five types of JA composites showed higher total phenol and flavonoid contents than those of JA concentrate. In addition, increased antioxidant and ${\alpha}$-glucosidase inhibitory activities were observed, with that of JA1 being the highest. However, all concentrations ($1{\sim}100{\mu}g/ml$) of JA tested did not affect the cell viability of Chang cells. In addition, JA induced the activation of AMP-activated protein kinase (AMPK) in Chang cells and significantly increased the glucose uptake in C2C12 cells. Therefore, it could be concluded that the JA composites (JA1 - 5) mixed with G. procumbens, M. charantia, and C. longa extracts were effective in increasing the extracts' antioxidant and antidiabetic activities.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.695-700
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• 2007

The cycloinulooligosaccharide fructanotransferase (CFTase) gene (cft) from Paenibacillus macerans (GenBank access code AF222787) was expressed on the cell surface of Saccharomyces cerevisiae by fusing with Aga2p linked to the membrane-anchored protein Aga1p. The surface display of CFTase was confirmed by immunofluorescence microscopy and enzymatic assay. The optimized reaction conditions of surface-displayed CFTase were as follows; pH, 8.0; temperature, $50^{\circ}C$; enzyme amount, 30 milliunit; substrate concentration, 5%; inulin source, Jerusalem artichoke. As a result of the reaction with inulin, cycloinulohexaose was produced as a major product along with cycloinuloheptaose and cycloinulooctaose as minor products.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.531-537
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• 1994

This study was undertaken with objective of optimizing the conditions of fermentation in an aqueous two-phase system which is composed of polyethylene glycol (PEG) 20000 and crude dextran (Dx). The data were obtained and analyzed using the Box-Wilson's experimental design protocol and the response surface methodology. To reach this end a multilinear polynomial regres- sion model was developed, which can be utilized for the purpose of optimizing the extractive fermentation. Optimum conditions for batch fermentation with aqueous two phase system were found to be at 4.2~5.4% PEG/3.2~4.2% Dx range. The composition of the center was 4.8% PEG/ 3.6% Dx. Optimum operating conditions for initial sugar concentration and fermentation time were approximately 160 g/l, and 21~22 hr, respectively. Fermentation in the aqueous two phase system composed of 5% PEG/4% Dx showed increase of 23% in ethanol concentration, of 9.5% in ethanol yield, and of 19% in ethanol productivity as compared to the case of fermentation of neat Jerusalem artichoke juice.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.277-285
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• 1997

Kluyveromyces marxianus var. marxianus isolated as an inulin-assimilating microorganism produces inulin fructotransferase (inulaseII) which catalyses the conversion of inulin into di-D-fructofuranose 1, 2' : 2, 3' dianhydrde (DFAIII). The DFA produced by the organism was isolated by using active carbon column, and identified as DFAIII by high performance liguid chromatography. The culture medium giving maximum inulaseII production was found to consist of 1% sucrose and 0.75% yeast nitrogen base (YNB). The inulasell production was induced by inulin or sucrose as a carbon source and increased by addition of YNB as a nitrogen source. Optimal initial pH of the culture medium, culture temperature and medium volume for the enzyme production were pH 4.7, 30$\circ$C and 140 ml, respectively. Under the optimal conditions described above, the enzyme activity in the culture supematant reached 4.2 units/ml after cultivation for 36 h. The DFAIII was accumulated at 13.25 mg/ml after 48 h of culture in the Jerusalem artichoke tuber medium.

• KSBB Journal
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• v.6 no.2
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• pp.175-180
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• 1991

The quantitative effects of molecular weight and concentrations of two phase-forming polymers-polyethylene glycol and crude dextran on the two phase extractive ethanol fermentation were investigated using a Box-Wilson central composite protocol. The regression model obtained was used in order to determine optimum compositions of aqueous two phase system. In the aqueous two phase extractive ethanol fermentation of Kluyueromyces fragilis CBS 1555 with Jerusalem artichoke juice, it was found from the regression model that the variables influenlcing on ethanol fermentation were PEG concentration, time, Dx concentration, and PEG molecular weight strongly in order. The interaction of PEG concentration and PEG molecular weight was also found, and the effect of PEG concentration decreased with increase in molecular weight of PEG. The ethanol concentration incresed with increase in molecular weight of PEG, and with decrease in concentration of PEG. In conolusion, maximum concentration of ethanol produced was obtained at the following compositions; PEG MW 20000, Dx concentration ranged from 4% to 5%, and PEG concentration ranged from 3% to 7%.

• Natural Product Sciences
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• v.8 no.4
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• pp.141-143
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• 2002

Two flavone glucosides have been isolated from the leaves of Helianthus tuberosus (jerusalem artichoke). Their structures were identified as kaempferol 3-O-glucoside (1) and quercetin 7-O-glucoside (2) by spectroscopic analysis and confirmed by comparison with reported data. These flavonoids were isolated for the first time from this plant part.