• Food Science and Biotechnology
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• v.15 no.5
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• pp.672-676
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• 2006

The aim of this study is to evaluate the antioxidant, antimicrobial, and antitumor activities of various concentrations of partially purified substance(s) from green tea seed (Camellia sinensis L.). The total polyphenol contents of each fraction (non-adsorption fraction: F-1, fraction eluted with 40% methanol: F-2, and fraction eluted with 100% methanol: F-3) purified by Diaion HP-20 column chromatography were, in the increasing order: F-1 (3.7 mg tannic acid equivalents, TAB/g) < F-3 (23.2 mg TAB/g) < seed extracts (26.2 mg TAB/g) < F-2 (42.7 mg TAB/g). The scavenging activities toward the 1,1-diphenyl-2-picyrylhydrazyl (DPPH) radical were, in decreasing order: F-2 (93.3%) > butylated hydroxytoluene (BHT; 89.8%) > ascorbic acid (89.3%) > leaf extracts (70.3%) > F-3 (15.9%) > seed extracts (15.8%) > F-1 (14.8%) at a 0.1% concentration. In studies on antimicrobial activities, the results indicate that the growth of yeast (Candida albicans KCCM 11282 and Cryptococcus neoformans KCCM 50544) was inhibited more so than that of other fungi (Alternaria alternate KCTC 6005 and Rhizoctonia solani). In addition, it appears that the antitumor activities of the F-1, F-2, and F-3 fractions at a concentration of $50\;{\mu}g/mL$ showed 6, 7, and 23% growth inhibition of the HEC-1B cell line, 14, 11, 82% inhibition of the HEP-2 cell line, and 8, 16, and 81% inhibition of the SK-OV-3 cell line, respectively. Overall these results indicate that the antioxidant activity is greatest in the F-2 fraction, and the antimicrobial and antitumor activities are greatest in the F-3 fraction.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.69-73
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• 2003

A novel antifungal antibiotic for azole-resistant Candida albicans was purified from the culture broth of Bacillus subtilis LAM 97-44 by butanol extraction, Diaion HP-20 and Dowex-50 adsorption chromatography, silica gel flash chromatography followed by HPLC and designated LAM-44A. LAM-44A was stable for 60 min at $100^{\circ}C$, and pH range from 2 to 10. MIC values were observed at $0.5-3.5\;{\mu}g/ml$ against various Candida albicans strains. The antibiotic showed no cytotoxicity for S180, MKN-45, P388, HeLa and 373 at the concentration of 1 mg/ml. LAM-f4A was colorless powder soluble in water, methanol, ethanol, butanol and negative to ninhydrin reaction. The antibiotic had maximum absorption at 273 nm in methanol, and melting point was $202^{\circ}C$. The molecular weight and formula were determined to be 282 and $C_{14}H_{34}O_5$ by $^1H-NMR,\;^{13}C-NMR$, IR spectrum and elemental analysis.

• Journal of Life Science
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• v.14 no.2
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• pp.225-228
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• 2004

Natamycin, produced by Streptomyces natalensis ATCC27448, is a polyene macrolide antibiotic, is widely used in the food industry in order to prevent mould contamination. This study carried out to develop an efficient purification process of natamycin from fermentation broth. The stability of natamycin in fermentation broth during storage period was investigated at 4$^{\circ}C$ and room temperature. After the storage of fermentation broth for 14 days at 4$^{\circ}C$, residual activity of natamycin was about 80% but decreased by 27% at room temperature. As solvent to extract natamycin from fermentation broth, methanol was the most efficient. A developed purification procedure includes methanol extraction and Diaion HP-20 column chromatography. Approximately 2.9 g of natamycin was obtained with a final yield of 69.1% and purity of 96.6% from 1.8 l of fermentation broth by this developed purification procedure.

• Food Engineering Progress
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• v.15 no.3
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• pp.276-281
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• 2011

The optimum condition for the extraction and purification processes of phytic acid from defatted rice bran was examined. The phytic acid was efficiently extracted when the defatted rice bran was treated with 10 volumes of 0.5% HCl for 1 hr. For the neutralization of acid-treated extract, 0.5% NaOH was the most acceptable. To purify phytic acid, Diaion HP20 resin was used to remove impurities from the extract. The flow-through was then loaded onto ion exchange columns packed with various resins and among them, Amberlite IRA-416 resin showed highest recovery yield. When the phytic acid was absorbed onto Amberlite IRA-416 resin and then eluted with 0.5% NaOH, 89% of applied phytic acid was eluted. Most proteins were removed from the purified phytic acid and total protein content of the phytic acid was 0.14%(w/w).

• Food Engineering Progress
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• v.13 no.4
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• pp.243-250
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• 2009

Pravastatin sodium, competitive inhibitors of HMG-CoA(3-hydroxy-3-methylglutaryl coenzyme A) reductase, is produced from the culture broth of Streptomyces carbophilus KCCM 10370, The production of Pravastatin sodium was increased about 45 fold compared to wild type by UV mutation. Production of Pravastatin was also improved by continuous feeding of Compactin sodium to 24% and bioconversion ratio was also increased to 4.3% by intermittent addition. In main culture, concentration of Compactin sodium was kept less than 0.1%(w/v) under continuous feeding of Compactin sodium then product was 0.49% and bioconversion was 70%. After finishing the fermentation, Pravastatin was purified by various chromatographies such as Diaion HP20 resin column, Partition, and ODS(Octa-Decylsilyl Silicagel) resin column with a final yield of 70~72% and over 99.7% purity. The IR, UV, and NMR study of the purified Pravastatin sodium showed the same pattern as that of EP(European Pharmacopoeia).

• Applied Biological Chemistry
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• v.26 no.4
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• pp.222-230
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• 1983

This study was designed to develop a process for the immobilization of xylose isomerase(D-xylose ketol isomerase, EC 5.3.1.5) from Streptomyces griseolus previously isolated by the authors and its application on a pilot plant scale for the production of high fructose corn syrup. The biomass which has endo-excreted xylose isomerase was homogenized under a pressure of $500kg/cm^2$ and 90.8% of the enzyme recovery of the native activity was obtained as compared to 54.7% recovery by the lysozyme treatment. Ionic bonding method was adopted for the enzyme immobilization due to its many reported merits. It was found that the porous resins such as Diaion HP 20, Duolite A-7, Amberlite IRA 93 and 94 were effective in immobilizing the enzyme. In addition, it was disclosed that the regeneration form of $BO_4--$ is effective for Amberlite IRA 93 and $HCO_3-$ for Diaion HP 20. Optimal immobilization condition for Amberlite IRA 93 was pH 8.0 and $55^{\circ}C$ yielding 80.6% of immobilization. Activity decay test showed half life of the immobilized enzyme with Amberlite IRA 93 was more than 24 days at $65^{\circ}C$. The carrier was evaluated to be resuable and its result showed the relative immobilization yields were 98.2, 93.3, 90.7 and 87.5%, respectively at second, third, forth and fifth rebinding test of the enzyme on Amberlite IRA 93. Optimal temperature of the immobilized enzyme was slightly lowered and the range widened to $60\sim70^{\circ}C$, while optimal pH moved toward $8.0\sim8.3$ in its isomerization reaction. The trial production result of high fructose corn syrup in pilot scale immobilization showed that one liter of immobilized xylose isomerase (350 IXIU/ml-R) is capable producing about 293l high fructose corn syrup(75% dry substance) in 30 days.

• Journal of Life Science
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• v.32 no.1
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• pp.1-10
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• 2022

Natural products have gained increasing attention due to their advantage of long-term safety and low toxicity for a very long time. Torreya nucifera is widespread in southern Korea and Jeju Island and its seeds are commonly used as edible food. Oriental ingredients have often been reported for their insecticidal, antioxidant and antibacterial properties, but there have not yet been any studies on their antidiabetic effect. In this study, we investigated several biological activities of T. nucifera pericarp (TNP) and seeds (TNS) extracts and proceeded to characterize the antidiabetic compounds of TNS. The initial results suggested that TNS extract at 15 and 10 ㎍/ml concentration has inhibitory effects on α-glucosidase and protein tyrosine phosphatase 1B, that is 14.5 and 4.35 times higher than TNP, respectively. Thus, the stronger antidiabetic TNS was selected for the subsequent experiments to characterize its active compounds. Ultrafiltration was used to determine the apparent molecular weight of the active compounds, showing 300 kDa or more. Finally the mixture was then partially purified using Diaion HP-20 column chromatography by eluting with 50~100% methanol. Therefore we concluded that the active compounds of TNS have potential as therapeutic agents in functional food or supplemental treatment to improve diabetic diseases.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.577-580
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• 1995

During the screening for the antimicrobial agents against multidrug-resistant Staphylococcus aureus, we isolated an active compound produced by strain CNU30122. The active compound was purified from culture broth by HP-20 column chromatography, ethylacetate extraction. silica gel column and Sephadex LH-20 column chromatographies and HPLC. Based on various NMR studies including $^1H-^1H\;COSY$, $^1H-^{13}C\;COSY$ and HMBC experiments. the active compound was identified as fusidic acid.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.284-288
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• 1998

This study was carried out to establish a new efficient method for isolation and purification of ginsenosides. Silica gel column chromatography, having been used for the isolation of ginsenosides, is advantageous to obtain a large amount of ginsenosides. However, it has a disadvantage to isolate ginsenosides to their highest purity. In addition, normal-or reverse-phase HPLC method thus far reported is confined to quantitative analysis. Especially, it has not been possible to isolate racemic 20(S)- and 20(R)-ginsenoside Rg2. In this experiment, isolation and purification of ginsenosides were accomplished by Diaion HP-20 adsorption chromatography, silica gel column chromatography, recrystalization and Prep. HPLC with or without Prep. TLC. From this study, we could establish a new efficient method for isolation and purification of 9 major and/or minor ginsenosides.

• Journal of Life Science
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• v.23 no.3
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• pp.333-340
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• 2013

This study was performed to determine whether stem bark extract containing saponin of Albizzia julibrissin in the diet influences gonadal maturation and spawning in medaka (Oryzias latipes). The crude extraction containing saponin (HaBC) was partially purified from n-BuOH extraction of A. julibrissin stem bark by Diaion HP-20, Silica gel and Sephadex LH-20 chromatographies. We fed diets supplemented with HaBC to medaka. We then studied the effects of the HaBC supplement on the suppression of gonadal maturation and spawning in female medaka that were reared in aquaria with recirculation systems. In the experiment with immature female medaka, the periods of initiation of gonadal maturation and spawning were delayed in the fish that were fed diets supplemented with at least HaBC 20 mg/g-feed. In the experiment with mature female medaka, the fish that were fed diets supplemented with at least HaBC 20 mg/g-feed had lower GSIs than the control diet group did. The results showed that the growth of the immature medaka was not correlated with the amount of supplementation of HaBC in the diet. However, the condition factors (CF) in the medaka that were fed diets supplemented with at least HaBC 20 mg/g-feed were higher than in the medaka fed on the control diet. We concluded that extracts containing saponin from the stem bark of A. julibrissin have the potential to inhibit gonadal maturation in female medaka, but they did not act as growth stimulation. Further studies are required to determine the mechanism of the action.