• Journal of Life Science
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• v.9 no.1
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• pp.26-34
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• 1999

A thermostable pullulanase has been isolated and purified from Thermus caldophilus GK-24 to a homogeneity by gel-filtration and ion-exchange chromatography. The specific activity of the purified enzyme was 431-fold increase from the crude culture broth with a recovery of 11.4%. The purified enzyme showed $M_{r}$ of 65 kDa on denaturated and natural conditions. The pI of the enzyme was 6.1 and Schiff staining was negative, suggesting that the enzyme is not a glycoprotein. The enzyme was most active at pH 5.5. The activity was maximal at $75^{\cire}C$ and stable up to $95^{\cire}C$ for 30 min at pH 5.5. The enzyme was stable to incubation from pH 3.5 to pH 8.0 at $4^{\cire}C$ for 24hr. The presence of pullulan protected the enzyme from heat inactivation, the extent depending upon the substrate concentration. The activity of the enzyme was simulated by $Mn^{2+}$ ion, }$Ni^{2+}$, $Ca^{2+}$, $Co^{2+}$ ions. The enzyme hydrolyzed the ${\alpha}$-1,6-linkages of amylopectin, glycogens, ${\alpha}$, ${\beta}$-limited dextrin, and pullulan. The enzyme caused the complete hydrolysis of pullulan to maltotriose and the activity was inhibited by $\alpha$, $\beta$, or $\gamma$-cyclodextrins. The $NH_{2}$-terminal amino acid sequence [(Ala-Pro-Gln-(Asp of Tyr)-Asn-Leu-Leu-Xaa-ILe-Gly-Ala(Ser)] was compared with known sequences of various sources and that was compared with known sequences of various sources and that was different from those of bacterial and plant enzymes, suggesting that the enzymes are structurally different.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.504-510
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• 1988

The physicochemical properties of rice flours which were obtained by dry milling(blade, hammer, test and micro mill) and wet & dry milling (roller & micro mill) were investigated. The resulting flour particle sizes were reduced in the order that of blade, hammer, test, micro and roller & micro mill. Scanning electron microscopic examination showed that the starch granules were freed from the imbedding matrix as the particles became finer. The test-milled flour had the hightest levels of starch damage, maltose value and hot-water soluble amylose content, and the blade-milled flour showed the lowest levels. Amylograph viscosity and gelatinization temperature of the flours decreased as the particles became finer, and the addition of $Hg^{+2}$ increased the peak viscosity of the dry-milled flour pastes, whereas the wet & dry-milled flour did not show any changes. The blue values and ${\lambda}$max values of the iodine complex of the cold-water extractable ${\alpha}-D-glucan$ from flours were in the range of 0.023-0.029 and 518-522nm, respectively, indicating these materials were shown to be mainly composed of amylopectin-like polymer.

• KSBB Journal
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• v.14 no.3
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• pp.384-388
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• 1999

We have used high pH anion-exchange chromatography to analyze low level (below $20{\mu}M$) $\alpha$-D-glucose-1-phosphate (G-1-P) that can be used as a cytostatic compound, an antibiotic, and immunosuppressive drug. Our chromatographic method afforded excellent peak resolution and seletivity for glucose-6-phosphate and various maltooligosaccharides as well as G-1-P. The pulsed amperometric detector yielded linear response on G-1-P ranging from 2 - $20{\mu}M$, giving slope of $4.8{\times}10^4$(peak area/${\mu}M$). The detection limit was $2{\mu}M$. This method was applied to the purification of thermophilic $\alpha$-glucan phosphorylase from Thermus caldophilus. The technique will be extremely useful in future studies concerning carbohydrate metabolism in living organisms.

• IMMUNE NETWORK
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• v.4 no.2
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• pp.94-99
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• 2004

Background: We previously reported that ginsan, a polysaccharide extracted from Panax ginseng had an immunostimulatory activity such as mitogenic activity, activation of macrophages and killer cells, and production of a variety of cytokines which resulted in antitumor and antiseptic effects. We further purified $\alpha$-(1$\longrightarrow$6)-glucan and $\beta$-(2$\longrightarrow$6)-fructan from the ginsan with size exclusion and ion-exchange column chromatography successively. In this study, we performed the structure-based activity of ginsan by comparison with known polysacchrides such as $\beta$-glucan, curdlan, laminarin, levan, dextran, lentinan and OK-432. Methods: To investigate the immunostimulatory activity of several polysaccharide compounds, we investigated the stimulation of lymphocytes proliferation, the generation of activated killer cells and the secretion of nitrites from activated macrophages. Results: Of polysaccharides tested, curdlan and ginsan stimulated lymphocyte proliferation, suggesting that the molecular weight and composition of polysaccharide are dependent on the mitogenic activity. The production of nitric oxide was significantly increased in curdlan, levan, ginsan and its fraction, indicating that fructan has also capacity to activate macrophages and may devote to kill pathogens. In addition, the activation of macrophages was seemed to be independent of molecular weight of polysaccharide. The generation of AK cells was exhibited in order of curdlan, OK-432> F1, ginsan, F3> levan> etc. The AK activity may be dependent on molecular weight and composition of polysaccharides. Conclusion: Unfortunately, purified polysaccharide from ginsan were less active on immunostimulatory activity than mixed compounds of polysaccharides. From the viewpoint of structure and activity relationships, we found several characteristic features.

• The Journal of Korean Medicine
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• v.30 no.4
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• pp.1-12
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• 2009

Objectives: This study was to investigate the anti-oxidation and anti-cancer activity of Chaga mushroom extract. Extraction condition optimization and beta-glucan analysis and anti-cancer activity tests were also done. Methods: Optimum extraction conditions for Chaga mushroom extract were at a temperature of $90^{\circ}C$ and 2hrs with 10 times of water. Extraction yield and economics were best under these conditions. Results: Anti-oxidation activity was the highest with the fraction of 100,000 MWCO and $IC_{50}$ value was $13{\mu}g/ml$ and this value was comparable to that of vitamin E, alpha-tocopherol. Among the fractions from various organic solvents, ethyl acetate fraction showed the highest anti-oxidation activity with $IC_{50}$ value of $7{\mu}g/ml$. For anti-cancer activity, chloroform fraction showed little anti-cancer activity and ethyl acetate fraction showed the best anti-cancer activity with $IC_{50}$ $1.5{\mu}g/ml$ for stomach cancer cells. Anti-cancer activities for different molecular weight fractions were the best in the fraction of molecular weight less than 100,000Da, and $IC_{50}$ values for stomach cancer cells and liver cancer cells were 1.7 and $1.4{\mu}g/ml$, respectively. Conclusions: From these results, we can conclude that the extract of Chaga mushroom could be a good source for functional food and natural anti-cancer medicine.

• Biomolecules & Therapeutics
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• v.21 no.4
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• pp.290-298
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• 2013

This study examined the effects of calcium (Ca) gluconate on collagen-induced DBA mouse rheumatoid arthritis (CIA). A single daily dose of 200, 100 or 50 mg/kg Ca gluconate was administered orally to male DBA/1J mice for 40 days after initial collagen immunization. To ascertain the effects administering the collagen booster, CIA-related features (including body weight, poly-arthritis, knee and paw thickness, and paw weight increase) were measured from histopathological changes in the spleen, left popliteal lymph node, third digit and the knee joint regions. CIA-related bone and cartilage damage improved significantly in the Ca gluconate-administered CIA mice. Additionally, myeloperoxidase (MPO) levels in the paw were reduced in Ca gluconate-treated CIA mice compared to CIA control groups. The level of malondialdehyde (MDA), an indicator of oxidative stress, decreased in a dose-dependent manner in the Ca gluconate group. Finally, the production of IL-6 and TNF-${\alpha}$, involved in rheumatoid arthritis pathogenesis, were suppressed by treatment with Ca gluconate. Taken together, these results suggest that Ca gluconate is a promising candidate anti-rheumatoid arthritis agent, exerting anti-inflammatory, anti-oxidative and immunomodulatory effects in CIA mice.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1618-1618
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• 2001

Predicting quality traits using near infrared (NIR) spectroscopy on whole grain samples has gained wide acceptance as a non-destructive, rapid and cost effective technique. Barley breeding programs throughout southern Australia currently use this technology as a tool for selecting malting quality lines. For the past 3 years whole grain barley calibrations have been developed at VIDA to predict malting quality traits in the early generation selections of the breeding program. More recently calibrations for whole grain malt have been developed and introduced to aid in selecting malted samples at the mid-generation stage for more complex malting quality traits. Using the same population set, barley and malt calibrations were developed to predict hot water extracts (EBC and IoB), diastatic power, free $\alpha$-amino nitrogen, soluble protein, wort $\beta$-glucan and $\beta$-glucanase. The correlation coefficients between NIR predicted values and laboratory methods for malt were all highly significant ($R^2$ > 0.84), whereas the correlation coefficients for the barley calibrations were lower ($R^2$ > 0.57) but still significant. The magnitude of the error in predicting hot water extract, diastatic power and wort $\beta$-glucan using whole grain malt was reduced by 50% when compared with predicting the same trait using whole grain barley. This can be explained by the complex nature of attempting to develop calibrations on whole grain barley utilizing malt data. During malting, the composition of barley is modified by the action of enzymes throughout the steeping and germination stages and by heating during the kilning stage. Predicting malting quality on whole grain malt is a more reliable alternative to predicting whole grain barley, although there is the added expense of micro-malting the samples. The ability to apply barley and malt calibrations to different generations is an advantage to a barley breeding program that requires thousands of samples to be assessed each year.

• Molecules and Cells
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• v.28 no.4
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• pp.369-373
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• 2009

Heterologous secretory expression of endoglucanase E (Clostridium thermocellum) and ${\beta}$-glucosidase 1 (Saccharomycopsis fibuligera) was achieved in Saccharomyces cerevisiae fermentation cultures as an ${\alpha}$-mating factor signal peptide fusion, based on the native enzyme coding sequence. Ethanol production depends on simultaneous saccharification of cellulose to glucose and fermentation of glucose to ethanol by a recombinant yeast strain as a microbial biocatalyst. Recombinant yeast strain expressing endoglucanase and ${\beta}$-glucosidase was able to produce ethanol from ${\beta}$-glucan, CMC and acid swollen cellulose. This indicates that the resultant yeast strain of this study acts efficiently as a whole cell biocatalyst.

• Journal of Mushroom
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• v.18 no.1
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• pp.100-106
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• 2020

Eight morel mushroom species were collected from Korea and other countries. The culture characteristics, genetic relationships, and beta-glucan content of the strains were analyzed. The mycelia of Morchella species exhibited optimal growth when cultured in dark at 25 ℃ in media with pH 7. The mycelia had a distinctive mycelial scent and characteristically changed color, being white initially, and then turning dark yellow to dark brown as it grew. The mycelia were classified into five types based on morphology. The isolates were identified as Morchella conica, two M. sextelata, M. importuna, M. esculenta, and three M. crassipes, based on ITS-rDNA sequences. PCR polymorphisms were variably produced within Morchella spp. using Universal Fungal Fingerprinting Primers (UFPF) and classified into four groups at the intra and inter species level. The strains, KMCC04971 and KMCC04407, showed the same banding pattern as M. conica and M. sextelata, respectively; however, these results were different from those of ITS analysis. Glucan content analysis by strain showed that the KMCC 04973 strain of M. importuna had the highest alpha- and beta-glucan content, at 16.4 g and 33.1 g per 100 g, respectively.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.620-628
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• 2012

We examined the effects of biological activity Phellinus linteus mycelium culture with cassiae semen extract. Firstly, the optimal temperature, initial pH and culture period for mycelial growth in a liquid culture of P. linteus were determined, and they were $30^{\circ}C$, pH 5.0 and 8 days respectively. The five herbal materials were examined against several health functional efficacies, and, as a result, Cassiae semen was chosen, with its superior inhibitory effects in ${\beta}$-glucuronidase inhibitory activity, electron donating activity, ACE inhibitory, and ${\alpha}$-glucosidase inhibitory activities(95.3%, 80.9%, 96.1 and 24.2%, respectively). P. linteus fruit body was investigated on ${\beta}$-glucuronidase inhibitory activity, electron donating activity, ACE inhibitory, and ${\alpha}$-glucosidase inhibitory activities, and they were 54.7%, 81.9%, 30.0% and 20.1%, respectively. Accordingly, C. semen was used in the following experiment, to give an additive functional effect on the P. linteus. As the amount of C. semen in the cultural media increased, mycelial weight and ${\beta}$-glucan contents also increased, but final pH was not influenced. In addition, the ${\beta}$-glucuronidase inhibitory activity, electron donating activity, and ${\alpha}$-glucosidase inhibitory activity increased. P. linteus mycelium culture showed higher activities in the other three tests above, except for electron donating activity, when C. semen was added to the medium before cultivation.