• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1269-1275
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• 2006

The selection of multienzyme complex-producing bacteria under aerobic condition was conducted for improving the degradation of lignocellulosic substances. The criteria for selection were cellulase and xylanase enzyme production, the presence of cellulose-binding domains and/or xylan-binding domains in enzymes to bind to insoluble substances, the adhesion of bacterial cells to insoluble substances, and the production of multiple cellulases and xylanases in a form of a high molecular weight complex. Among the six Bacillus strains, isolated from various sources and deposited in our laboratory, Paenibacillus curdlanolyticus B-6 strain was the best producer of cellulase and xylanase enzymes, which have both cellulose-binding factors (CBFs) and xylan-binding factors (XBFs). Moreover, multiple carboxymethyl cellulases (CMCases) and xylanases were produced by the strain B-6. The zymograms analysis showed at least 9 types of xylanases and 6 types of CMCases associated in a protein band of xylanase and cellulase with high molecular weight. These cells also enabled to adhere to both avicel and insoluble xylan, which were analyzed by scanning electron microscopy. The results indicated that the strain B-6 produced the multienzyme complex, which may be cellulosome or xylanosome. Thus, P. curdlanolyticus B-6 was selected to study the role and interaction between the enzymes and their substrates and the cooperation of multiple enzymes to enhance the hydrolysis due to the complex structure for efficient cellulases and xylanases degradation of insoluble polysaccharides.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4027-4034
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• 2011

$CaCO_3$ crystalline structures having novel assemblies were in situ fabricated as analogs of naturally occurring proteins and polysaccharides for biomineralization. The calcite crystal was mineralized in a poly(vinyl alcohol)-$Ca^{2+}$ complex film immersed in a $Na_2CO_3$ solution containing poly(aspartic acid). The morphology and size of the $CaCO_3$ crystals were tuned by varying the concentration of poly(aspartic acid). The mechanisms of their nucleation orientation and formation were investigated experimentally and through molecular dynamics (MD) simulations in order to obtain a better understanding of the interactions between the polymers and the crystal at the molecular level. Both the MD results and experimental results indicate that the interaction between PVA and calcite mainly depends on the concentration of the polymer. The novel approach proposed herein for the fabrication of inorganic crystalline assembly structures can be used to fabricate precise crystalline structures.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.90-91
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• 2000

The physiological systems that control blood fluidity are both complex and elegant. Blood must remain fluid within the vasculature and yet clot quickly when exposed to nonendothelial surfaces at sites of vascular injury. There are two principle mechanisms to control a delicate balance in higher organisms (Davie & Ratnoff, 1964). Present evidence suggests that the intrinsic pathway play an important role in the growth and maintenance of fibrin formation in the coagulation cascade while a second overlapping mechanism, called the extrinsic pathway, is critical in the initiation of fibrin formation. Coagulation factors is in two mechanisms, and in order to clot blood, they are activated by a cooperation with $Ca^{2+}$, phospholipid and vitamin K etc. For example, the human placental anticoagulant protein (PAP of PAP- I), which is a $Ca^{2+}$ -dependent phospholipid binding protein (Funakoshi et al., 1987) inhibited the activity of factor Xa, so that it prolonged fibrin formation. We wondered whether any other protein was involved in regulation of the coagulant system as an anticoagulant protein from natural organisms. Natural agents would have not harmful side-effects in comparision with chemically synthesized materials such as warfarin, aspirin, phenindione, etc.. But anticoagulant agents from natural, especially marine organisms have hardly been researched except for polysaccharides from marine algae. (omitted)

• Mycobiology
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• v.42 no.4
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• pp.311-316
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• 2014

Lichen studies, including biodiversity, phylogenetic relationships, and conservation concerns require definitive species identification, however many lichens can be challenging to identify at the species level. Molecular techniques have shown efficacy in discriminating among lichen taxa, however, obtaining genomic DNA from herbarium and fresh lichen thalli by conventional methods has been difficult, because lichens contain high proteins, polysaccharides, and other complex compounds in their cell walls. Here we report a rapid, easy, and inexpensive protocol for extracting PCR-quality DNA from various lichen species. This method involves the following two steps: first, cell breakage using a beadbeater; and second, extraction, isolation, and precipitation of genomic DNA. The procedure requires approximately 10 mg of lichen thalli and can be completed within 20 min. The obtained DNAs were of sufficient quality and quantity to amplify the internal transcribed spacer region from the fungal and algal lichen components, as well as to sequence the amplified products. In addition, 26 different lichen taxa were tested, resulting in successful PCR products. The results of this study validated the experimental protocols, and clearly demonstrated the efficacy and value of our KCl extraction method applied in the fungal and algal samples.

• Advances in Traditional Medicine
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• v.4 no.1
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• pp.1-8
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• 2004

Ginseng root has been used as a tonic remedy in Traditional Chinese Medicine for centuries. Modern studies have demonstrated that ginseng root has complex components and multiple pharmacological properties. The effects of ginseng leaf, however, are not well known. Recent studies show that compared to ginseng root, ginseng leaf and stem exhibit a higher content of active compositions such as ginsenosides, polysaccharides, triterpene flavonoids, volatile oil, polyacetylenic alcohols, peptides, amino acids and fatty acids. Ginseng leaf possesses multiple pharmacological effects in the central nervous, cardiovascular, growth and metabolism systems. Additionally, the leaf has anti-fatigue, anti-hyperglycemic, anti-oxidant, and anti-aged effects. In general, ginseng leaf is quite safe, but adverse effects may occur if it is abused or is of poor quality. Thus, attention must be paid to dosages, quality, and standardization of ginseng leaf products.

• Korean Journal of Microbiology
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• v.31 no.3
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• pp.179-183
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• 1993

A restricted facultatively methanol-oxidizing bacterium, Methylovorus sp. strain SS1, was isolate dfrom soil samples from Kuala Lumpur, Malaysia, through methanol-enrichment culture technique. The isolate was nonmotile Gram-negative rod and did not have complex internal membrane system. The colonies were small, pale-yellow, and raised convex with entire margin. The cell did not produce any spores and capsular materials. The cell was obligately aerobic and exhibited catalase, but no oxidase, activity. Plasmid, carotenoid pigment, and poly-.betha.-hydroxybutyric acid were not found. The guanine plus cytosine content of the DNA was 55%. The isolate was found to grow only on methanol methylamine, or glucose. Growth factors were not required. Cells growing on methanol was found to produce extracellular polysaccharides containing glucose, lactose, and fructose. Growth was optimal (t$_{d}$= 1.7) with 0.5%(v/v) methanol at 40.deg.C and pH 6.5. No Growth was observed at over 60.deg.C. Cell-free extracts of the methanol grown cells exhibited the phenazine methosulfate-linked methanol dehydrogenase activity Methanol was found to be assimilate dthrough the ribulose monophosphate pathway.y.

• Journal of Microbiology and Biotechnology
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• v.6 no.3
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• pp.213-218
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• 1996

Hot-water extract, Fr. 1, of Phellinus linteus mycelium was fractionated into Fr. 2, 3, 4, and 5 by the difference of solubility in ethanol. The polysaccharide fractions were studied for their immunostimulating activity on in vitro T-independent polyc1onal antibody response to trinitrophenyl-haptened SRBC (sheep red blood cell). The Fr. 4 with the highest immunostimulating activity was subjected to DEAE-cellulose ion exchange chromatography and gave five fractions, 4-I, II, III, IV, and V. The in vitro immunostimulating assay of the five fractions showed that 4-I and 4-III had a similar activity to that of LPS but the other fractions had low activity. By analyses of chemical composition and HPLC, all fractions obtained were found to be heteropolysaccharide-protein complex. The molecular weights ranged from 9, 000 to 15, 000. Sugar analyses showed that glucose, galactose, mannose, arabinose, and xylose were main component. Uronic acid and amino sugar were also detected in the fractions. It should be noted that the molecular weight (15, 000) of 4-III was very small and the structure of 4-III may be different from the known immunostimulating branched $\beta$-(1longrightarrow3)-glucan.

• Journal of Applied Biological Chemistry
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• v.59 no.3
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• pp.215-220
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• 2016

Abstract Secondary cell wall is the most abundant biomass produced by plants. Plant secondary cell wall is composed of a complex mixture of cellulose, hemicellulose, and lignin. Lignin, a phenolic polymer that hinders the degradation of cell wall polysaccharides to simple sugars destined for fermentation to bio-ethanol. Cell wall biosynthesis pathway-specific biomass engineering offers an attractive 'genetic pretreatment' strategy to improve bioenergy feedstock. Recently, we found a transcription factor, MYB7, which is a transcriptional switch that may turns off the genes necessary for lignin biosynthesis. To gain insights into MYB7 mediated transcriptional regulation, we first established a dominant suppression system in Arabidopsis by expressing MYB7-SRDX. Then we used a transient transcriptional activation assay to confirm that MYB7 suppress the transcription of the lignin biosynthetic gene. Taken together, we conclude that MYB7 function as a repressor of the genes involved in the lignin biosynthesis.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1250-1257
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• 2005

Two groups of exopolysaccharides (designated as Fr-I EPS and Fr-II EPS) were isolated from the culture filtrate of new fungal strain Trichoderma erinaceum DG-312 by Sepharose CL-6B chromatography. The structures of the exopolysaccharides were investigated using gas chromatography (GC), Fourier transform-infrared (FT-IR) spectroscopy, GCMS analysis, and NMR. GC analysis indicated that Fr-I EPS was composed of mainly mannose ($78.9\%$) and galactose ($21.1\%$), whereas Fr-II EPS contained mannose ($68.4\%$), galactose ($26.2\%$), and glucose ($5.4\%$). In the anomeric region ($950-700cm_{-1}$) of the FT-IR spectrum, both EPSs exhibited obvious characteristic absorption of $810\;cm_{-1}$, indicating the existence of mannose. The spectra of $\alpha-and\;\beta$-configurations were assigned at 880 and $914\;cm_{-1}$, respectively. The results of GC-MS analyses confirmed that both EPSs were complex heteropolysaccharides with a ($1{\rightarrow}3$)-linked mannan backbone. The C-1 region that appeared in the $^{13}C-NMR$ spectra of these EPSs indicated a typical anomeric carbon signal. The Fr-I EPS showed two anomeric carbon signals at 102.6 and 99.6 ppm, whereas the Fr-II EPS displayed four anomeric carbon signals at 102.5, 99.6, 98.5, and 94.3 ppm. The molecular characteristics of the EPSs were further investigated using a size exclusion chromatography/multi-angle laser light scattering (SEC/MALLS) system. The SEC/MALLS system revealed that the average molar masses of the EPSs were $6.592{\times}10^{4}$ (Fr-I EPS) and $1.920{\times}10^{4}$ (Fr-II EPS) g/mol, and the molecular conformation of both EPSs in aqueous solution was random coils.

• Korean journal of food and cookery science
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• v.22 no.4 s.94
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• pp.477-487
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• 2006

The quality characteristics of dough and French breads containing dietary fibers, which were resistant starches (RS3 and RS4 types) and commercial non-starch polysaccharides (cellulose, pectin and chitosan), were investigated. The pH of the dough containing all dietary fiber except pectin was greater than that of control and was increased with increasing addition level. There was no correlation between pH and the expansion ratio of dough. As the level of added dietary fibers became high, the bread baking loss decreased, and the order of specific bread volume was 5% cellulose < 5% pectin < control bread, with no significant difference in specific volume. When a high level of dietary fibers was added to wheat flour, a complex phase appeared due to the formation between the network structure of additives and wheat gluten, and starch granules were heavily masted by the increased development of gluten-network matrix after the first fermentation like a wide spread net. Comparing the colorimetric changes of breads with the same added ratio (10%) of dietary fibers, the cellulose and RS4 addition breads had lower levels and the pectin-added bread had the highest value in the redness, while the chitosan-added bread had the highest value in the yellowness. Breads with a high level of dietary fibers showed increased hardness, gumminess, and brittleness and decreased springiness and cohesiveness. By sensory data, breads with 5% NSP and 10% RS addition showed high overall acceptability, with higher sensory RS score, compared to NSP addition. In conclusion, it was suggested that bread with lower than 10% RS or 5% NSP addition based on the amount of wheat flour, was acceptable with no considerable change in preference/overall quality and processing in bread-making.