• Preventive Nutrition and Food Science
• /
• v.16 no.4
• /
• pp.357-363
• /
• 2011

Recently, we found that Arthrobacter crystallopoietes N-08 isolated from soil directly produces trehalose from maltose by a resting cell reaction. In this study, the optimal set of conditions and substrate specificity for the trehalose production using resting cells was investigated. Optimum temperature and pH of the resting cell reaction were $55^{\circ}C$ and pH 5.5, respectively, and the reaction was stable for two hours at $37{\sim}55^{\circ}C$ and for one hour at the wide pH ranges of 3~9. Various disaccharide substrates with different glycosidic linkages, such as maltose, isomaltose, cellobiose, nigerose, sophorose, and laminaribiose, were converted into trehalose-like spots in thin layer chromatography (TLC). These results indicated broad substrate specificity of this reaction and the possibility that cellobiose could be converted into other trehalose anomers such as ${\alpha},{\beta}$- and ${\beta},{\beta}$-trehalose. Therefore, the product after the resting cell reaction with cellobiose was purified by ${\beta}$-glucosidase treatment and Dowex-1 ($OH^-$) column chromatography and its structure was analyzed. Component sugar and methylation analyses indicated that this cellobiose-conversion product was composed of only non-reducing terminal glucopyranoside. MALDI-TOF and ESI-MS/MS analyses suggested that this oligosaccharide contained a non-reducing disaccharide unit with a 1,1-glucosidic linkage. When this disaccharide was analyzed by $^1H$-NMR and $^{13}C$-NMR, it gave the same signals with ${\alpha}$-D-glucopyranosyl-(1,1)-${\alpha}$-D-glucopyranoside. These results suggest that cellobiose can be converted to ${\alpha},{\alpha}$-trehalose by the resting cells of A. crystallopoietes N-08.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2007.04a
• /
• pp.65-73
• /
• 2007

The objective of this study is to understand how regulatory mechanisms respond to sugar status for more efficient carbon utilization and source-sink regulation in plants. So, we need to identify and characterize many components of sugar-response pathways for a better understanding of sugar responses. For this end, genes responding change of sugar status were screened using Arabidpsis cDNA arrays, and confirmed thirty-six genes to be regulated by sucrose supply in detached leaves by RNA blot analysis. Eleven of them encoding proteins for amino acid metabolism and carbohydrate metabolism were repressed by sugars. The remaining genes induced by sugar supply were for protein synthesis including ribosomal proteins and elongation factors. Among them, I focused on three hydrolase genes encoding putative $\beta$-galactosidase, $\beta$-xylosidase, and $\beta$-glucosidase that were transcriptionally induced in sugar starvation. Homology search indicated that these enzymes were involved in hydrolysis of cell wall polysaccharides. In addition to my results, recent transcriptome analysis suggested multiple genes for cell wall degradation were induced by sugar starvation. Thus, I hypothesized that enzyme for cell wall degradation were synthesized and secreted to hydrolyze cell wall polysaccharides producing carbon source under sugar-starved conditions. In fact, the enzymatic activities of these three enzymes increased in culture medium of Arabidopsis suspension cells under sugar starvation. The $\beta$-galactosidase encoded by At5g56870 was identified as a secretory protein in culture medium of suspension cells by mass spectrometry analysis. This protein was specifically detected under sugar-starved condition with a specific antibody. Induction of these genes was repressed in suspension cells grown with galactose, xylose and glucose as well as with sucrose. In planta, expression of the genes and protein accumulation were detected when photosynthesis was inhibited. Glycosyl hydrolase activity against galactan also increased during sugar starvation. Further, contents of cell wall polysaccharides especially pectin and hemicellulose were markedly decreased associating with sugar starvation in detached leaves. The amount of monosaccharide in pectin and hemicellulose in detached leaves decreased in response to sugar starvation. These results supported my idea that cell wall has one of function to supply carbon source in addition to determination of cell shape and physical support of plant bodies.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.12
• /
• pp.1725-1731
• /
• 2002

The distribution and activities of hydrolytic enzymes (cellulolyti, hemicellulolytic,pectinolytic and others) in the rumen compartments of Hereford bulls fed 100% alfalfa hay based diets were evaluated. The alfalfa proportion in the diet was gradually increased for two weeks. Whole rumen contents were processed into four fractions: Rumen contents including both the liquid and solid fractions were homogenized and centrifuged, and the supernatant was assayed for enzymes located in whole rumen contents (WRE); rumen contents were centrifuged and the supernatant was assayed for enzymes located in rumen fluids (RFE); feed particles in rumen contents were separated manually, washed with buffer, resuspended in an equal volume of buffer, homogenized and centrifuged and supernatant was assayed for enzymes associated with feed particles (FAE); and rumen microbial cell fraction was separated by centrifugation, suspended in an equal volume of buffer, sonicated and centrifuged, and the supernatant was assayed for enzymes bound with microbial cells (CBE). It was found that polysaccharide-degrading proteins such as $\beta$-1,4-D-endoglucanase, $\beta$-1,4-D-exoglucanase, xylanase and pectinase enzymes were located mainly with the cell bound (CBE) fraction. However, $\beta$-D-glucosidase, $\beta$-D-fucosidase, acetylesterase, and $\alpha$-L-arabinofuranosidase were located in the rumen fluids (RFE) fraction. Protease activity distributions were 37.7, 22.1 and 40.2%, and amylase activity distributions were 51.6, 18.2 and 30.2% for the RFE, FAE and CBE fractions, respectively. These results indicated that protease is located mainly in rumen fluid and with microbial cells, whereas amylase was located mainly in the rumen fluid.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.11
• /
• pp.1673-1679
• /
• 2003

Two hundred forty 1-d-old Arbor Acres broiler chicks were used to investigate the effects of Cu (II)-exchanged montmorillonite (CEM) or montmorillonite on the growth performance, intestinal microflora, bacterial enzyme activities and morphology of broilers. The chicks were assigned randomly into three groups with 80 chicks per treatment. The three dietary treatments were basal diet only (control group), basal diet +1 g $kg^{-1}$ montmorillonite, and basal diet +1 g $kg^{-1}$ CEM. The results showed that the addition of CEM to the diet increased significantly the body weight and feed efficiency, but a similarly significant increase was not found in broilers fed the diet containing montmorillonite. Supplementing the CEM in the diet of broilers also decreased the numbers of Clostridium perfringens and Escherichia coli in the small intestine and cecum. The addition of either CEM or montmorillonite to the diet depressed the activities of $\beta$-glucosidase and $\beta$-glucuronidase in the small intestinal and cecal contents. Data of villus height and crypt depth for duodenum, jejunum and ileum indicated that dietary addition of CEM or montmorillonite improved the small intestinal mucosal morphology.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.16 no.3
• /
• pp.117-122
• /
• 2016

제1형 고셔병(Gaucher disease type 1)은 리소좀 효소인 산성 ${\beta}$-글루코시다아제(acid ${\beta}-glucosidase$)의 결핍으로 인한 리소솜 축적 질환이다. 효소 활성도가 감소되어 기질이 축적되어, 간비종대, 빈혈, 혈소판감소증 및 골질환을 포함한 전신 증상이 발생한다. 재조합 효소 단백을 정맥 주입하는 효소 대체요법(Enzyme replacement therapy)는 지난 20년 넘게 고셔병의 표준 치료법이었다. 그러나 성공적인 효소 대체요법에도 불구하고, 심각한 폐증상과 골격 증상 등 고셔병 치료에 여전히 해결되지 않는 문제들이 남아 있다. 기질 감소 치료(Substrate reduction therapy)는 기질의 생합성을 억제하여 축적을 감소시킨다. 최근 새로운 경구용 기질감소 치료제인 엘리글루스타트(eliglustat)가 적합한 CYP2D6 대사 표현형을 가진 고셔병 성인 환자를 위한 1차 치료제로 미국과 유럽에서 승인되었다. 엘리글루스타트가 아직 한국에서는 쓰이지 않고 있지만, 본 종설에서는 문헌 검토를 통해 고셔병의 새로운 치료로서의 효소 대체요법을 소개하고자 한다. 아직 확고한 결론을 도출하기에는 연구 결과가 제한적이기는 하지만, 현재까지의 데이터에 따르면 엘리글루스타트는 임상 효능에 있어서 효소 보충 요법에 비열등성을 보인다. 장기 결과에 대한 추가 연구가 필요하지만, 엘리글루스타트의 승인은 해당 1형 고셔병 성인 환자들에게 경구 치료제라는 새로운 선택을 가능하게 하였다. 향후 국내에서 엘리글루스타트가 처방 가능해 지면, 각 환자 마다 철저한 평가를 통해 치료법을 선택할 수 있도록 해야 할 것이다. 나아가, 국내 1형 고셔병 환자들을 위해 엘리글루스타트의 사용에 관한 임상적 지침 또한 조만간 개발될 필요가 있다.

• Archives of Pharmacal Research
• /
• v.26 no.2
• /
• pp.157-161
• /
• 2003

The major ingredient of Persicae Semen is a cynogenic compound, amygdalin (D-mandelonitrile-$\beta$-gentiobioside). Controversial results on the anticancer activity of amygdalin were reported due to its conversion to its inactive isomer, neoamygdalin. In order to inhibit the epimerization of amygdalin, we used newly developed simple acid boiling method in preparation of Persicae Semen extract. HPLC analysis revealed most of amygdalin in Persicae Semen extract was active D-form. Persicae Semen extract was used to analyze its effect on cell proliferation and induction of apoptosis in human promyelocytic leukemia (HL-60) cells. Persicae Semen extract was cytotoxic to HL-60 cells with $IC_{50}$ of 6.4 mg/mL in the presence of 250 nM of $\beta$-glucosidase. The antiproliferative effects of Persicae Semen extract appear to be attributable to its induction of apoptotic cell death, as Persicae Semen extract induced nuclear morphology changes and internucleosomal DNA fragmentation.

• KSBB Journal
• /
• v.30 no.4
• /
• pp.166-174
• /
• 2015

In this study, an efficient whole cell-based biotransformation for the production of liquiritigenin was developed using Laetiporus sulphureus CS0218 as biocatalyst and aqueous extracts of Glycyrrhiza uralensis as co-substrate, respectively. In order to determine the efficacy of this method, the optimal bioconversion conditions including mycelial growth, three important enzyme activities (${\beta}$-glucosidase, ${\alpha}$-rhamnosidase and ${\beta}$-xylosidase), and apparent viscosity of culture broth were monitored. After optimization, aqueous extracts of G. uralensis were added to the culture medium to directly produce algycone liquiritigenin. By applying this strategy, 67.5% of liquiritin was converted to liquiritigenin at pH 3.0 after 9 days of incubation and finally liquiritigenin was purified from the reaction mixture. And then, their biological activities including anti-oxidant and superoxide dismutase were observed. In fact, purified liquiritigenin was capable of bi-directional functions (i.e., either up-regulation or down-regulation of SIRT1 which is associated with aging). The results indicate that this strategy would be beneficial to produce biologically active liquiritigenin and could be used in pharmaceutical, cosmetic and food applications.

• Preventive Nutrition and Food Science
• /
• v.9 no.3
• /
• pp.199-205
• /
• 2004

The effect of chitosan on enzymatic activities and on bioactive compounds was characterized during germination at $25^{\circ}C$ for 7 days to search for a method to produce a germinated black rice. The germination rate was reduced by the addition of lactate and chitosan. The rotting rate was greatly decreased by chitosan, suggesting that the addition of chitosan into a germination solution might be an effective method for controlling fungal contamination during the germination of cereals. The addition of 100 and 200 ppm chitosan increased $\alpha$-amylase activity after 7 days by up to 152 % and 197 %, respectively. The activities of $\beta$-amylase and $\beta$-glucosidase were lower with 200 ppm chitosan than in distilled water and 100 ppm lactate. The amount of total soluble phenolics and total flavonoids decreased rapidly for four days and thereafter remained constant until the seventh day. The antioxidant activity of germinated black rice, in terms of hydrogen-donating activity, increased slowly and did not correspond to the changes of total soluble phenolics and total flavonoids. The amount of phytic acid was reduced by the addition of 200 ppm chitosan compared to distilled water, indicating that chitosan could be used as an elicitor for the increase of phytase activity during the germination of black rice.

• Journal of Mushroom
• /
• v.13 no.1
• /
• pp.50-55
• /
• 2015

Glucan has been shown to have a significant role in the activation of the immune system, including increased activity of macrophages and so on. Sparassis latifolia (formerly S. crispa) is an edible mushroom abundant in dietary fiber and widely known to contain high levels of ${\beta}$-glucan. In the present study, fermentation broths containing soluble ${\beta}$-glucan were prepared by fermentation with mushrooms with four Lactobacillus species (L. plantarum subsp. Plantarum, L. acidophilus, L. helveticus, and L. delbrueckii subsp. Bulgaricus). After culturing four Lactobacillus spp. in MRS broth, each Lactobacillus was inoculated into MRS broth containing S. latifolia powder 5% (w/v) at $37^{\circ}C$ in an anaerobic incubator for five days. It showed that the ${\beta}$-glucan contents were different in each fermentation sample. The suitable conditions for the preparation of mushroom fermentation broths were investigated and discussed.

• Mycobiology
• /
• v.30 no.3
• /
• pp.166-169
• /
• 2002

Protein productivity by the cellulolytic fungi, Trichoderma viride(MTCC 800), Chaetomium globosum and Aspergillus terreus was compared in co-culture and mixed culture fermentations of cashewnut bran. Co-cultures were more effective in substrate saccharification, which ranged between $85{\sim}88%$ compared to the $62{\sim}67%$ saccharification shown by the monocultures. Maximum saccharification was induced by T. viride and C. globosum co-culture resulting in the highest 34% release of reducing sugars. The maximum 16.4% biomass protein and the highest protein productivity(0.58%) were shown by T. viride and A. terreus co-culture. A. terreus performed better in co-culture in the presence of T. viride rather than with C. globosum. Among the cellulolytic enzymes, FPase(Filter Paper Cellulase) activity was significantly higher in all the co-cultures and in the mixed culture than in their respective monocultures. Mixed culture fermentation involving all the three fungi was not effective in increasing the per cent saccharification or the biomass protein content over the co-cultures.