• Journal of the korean academy of Pediatric Dentistry
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• v.23 no.3
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• pp.764-773
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• 1996

The mutan containing $\alpha$-1,3 bond is an insoluble portion of glucan which is the main component of dental plaque. The secretion of mutanase was assessed with mutan-digesting Streptomyces isolated from soil, and the factors affecting its activity was studied, obtaining the following result. Mutan-digesting Streptomyces was identified as Streptomyces exfoliatus by its characteristics. The effect of dextranase was identified on the media containing blue dextran. A clear zone was produced by Streptomyces exfoliatus on the media containing blue mutan, so showing the secretion of mutanase. A clear zone was significantly produced on the media overlayed with agar containing blue mutan. A clear zone was produced at 2 days after the inoculation of Streptomyces exfoliatus on the media containing below a concentration of 0.025% glucose, at 3 days on the media containing 0.05 % glucose, and at 4 days on the media containing 0.1 % glucose. Mutan-digestion wasn't appeared early by adding other carbohydrates. The higher concentration of peptone, the later appearance of clear zone was on the media containing below a concentration of 0.1 % peptone. These results indicated that the secretion of mutanase was identified from mutan-digesting Streptomyces on the media containing blue mutan, and a clear zone was appeared lately on the media containing higher amount of glucose.

• KSBB Journal
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• v.6 no.1
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• pp.27-33
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• 1991

Hairy root induced by A. rhizogenes from potato tuber (Solanm tuberosum L.) synthesized the agropine and mannopine which were demonstrated with paper electrophoresis. And the starch contents in hairy root were increased gradually following the developmental stage. But protein contents were decreased. The activity of ${\beta}-glucan$ synthetase II(GSII) which is related to the cell wall biosynthesis was stimulated in hairy root on the developmental stage. And chloropromazine did not influence the activity of GS II while verapamil inhibited about 60% of the activity GS II. Therefore, these results showed $Ca^{2+}$ to be effective factor in the cell wall formation. Isozyme pattern of peroxidase was investigated in the callus and hairy root induced from potato tuber.

• KSBB Journal
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• v.8 no.2
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• pp.126-132
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• 1993

The objective of this study was to develop an artificial dentin for easy handle and accurate observation of the mechanism on dental caries and to screen biologically active materials from the extracts of traditional plants and fruits for prevention of early dental cares. In order to produce disc PAHA (artificial dentin), the powdered hydroxylapatite was immobilized in a 20% polyacrylamide gel. The characteristics of disc PAHA was very similar to the surface, figure and lattice of human enamel. After decalcification in 0.1M citric acid based on observation with SEM. The critical point of decalcification of disc PAHA by acids was found to be pH 5.0-5.5, which was hi agreement with human enamel. The degree of decalcification from disc PAHA in 0.1M citric acid solution was sixfold higher than that of human enamel. This result suggested that disc PAHA would be useful as a substitute of human enamel for in vitro experiment. The extracts of garlic and Flower Apple A, B seemed to inhibit growth of S. mutans. Especially, when the 300$\mu\ell$ of its extracts added to the medium to incubate S. mutans, F. apple B showed strongly an inhibitory effect in both the growth of S. mutans and the synthesis of insoluble glucan.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.621-632
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• 1994

This experiment was performed to study the effect of capsaicin on the excitatory amino acids (EAAs) neurotransmitter in medullary dorsal horn and to clarify the relationship between substance P and excitatory amino acids. Horizontal slice of rat medullary dorsal horn was prepared and perfused with modified Krebs-Ringer solution in brain slice chamber. Release of EAAs was induced by veratrine and capsaicin were added to perfusion solution to observe the changes in EAA release. Capsaicin and ruthenium red, capsaicin antagonist, were also systemically injected with 50mg/kg in first day and 100mg/kg in second day for 2 days. Medulla oblongata containing the medullary dorsal horn was isolated, homogenized and centrifused. Spernatant was freeze-dried and EAA was determined by HPLC. Release of glutamate and aspartate was significantly increased by veratrine or capsaicin, but veratrine evoked release of EAAs was blocked by capsaicin in vitro, and injected ruthenium red did not have effect on the contents of EMs in vivo. Systemically injected capsaicin evoked the slight decrease in content of glutamate and aspartate in medullary dorsal horn and this effect of capsaicin was unaffected by ruthenium red.

• Korean journal of food and cookery science
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• v.28 no.5
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• pp.569-577
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• 2012

The physicochemical characteristics and biological activities, including antioxidant activity, antimutagenicity, and cytotoxicity of hot-water extract of fruiting body of Hericium erinaceus, were investigated in this study. Hot-water extract of fruiting body of Hericium erinaceus contained carbohydrate (7.86%), protein (10.91%), and ${\beta}$-glucan (3.62%). Water solubility of hot-water extract was 42.58%. Antioxidant activities of the extract were evaluated by ABTS assay and FRAP assay. The $IC_{50}$ value was 312.21 ${\mu}g/mL$ in ABTS assay. Antimutagenic activity of the extract was evaluated by Ames test. Antimutagenicity of hot-water extract (5 mg/mL) on Salmonella Typhimurium TA100 mutagenated by sodium azide (0.15 ${\mu}g/mg$) was 69.2%. Cytotoxicity of hot-water extract was also evaluated by MTT and SRB assay. The cytotoxicity was highest (83.95%) on Hep3B treated with 2,000 ${\mu}g/mL$ of hot-water extract in SRB assay. Therefore, it is suggested that hot-water extract of fruiting body of Hericium erinaceus has high antioxidant activity, antimutagenicity, and cytotoxicity.

• The Plant Pathology Journal
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• v.31 no.1
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• pp.1-11
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• 2015

Antimicrobial cyclic peptides derived from microbes bind stably with target sites, have a tolerance to hydrolysis by proteases, and a favorable degradability under field conditions, which make them an attractive proposition for use as agricultural fungicides. Antimicrobial cyclic peptides are classified according to the types of bonds within the ring structure; homodetic, heterodetic, and complex cyclic peptides, which in turn reflect diverse physicochemical features. Most antimicrobial cyclic peptides affect the integrity of the cell envelope. This is achieved through direct interaction with the cell membrane or disturbance of the cell wall and membrane component biosynthesis such as chitin, glucan, and sphingolipid. These are specific and selective targets providing reliable activity and safety for non-target organisms. Synthetic cyclic peptides produced through combinatorial chemistry offer an alternative approach to develop antimicrobials for agricultural uses. Those synthesized so far have been studied for antibacterial activity, however, the recent advancements in powerful technologies now promise to provide novel antimicrobial cyclic peptides that are yet to be discovered from natural resources.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.200-215
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• 2002

There are some international standards and organization controling the quality characteristics of varieties and seeds such as UPOV, OECD, ISTA, AOSA. The National List system to check variety performance such as quality characteristics of plant varieties and seeds was established by each countries. The UPOV (International Union for the Protection of New varieties of Plant) regulates the requirement of plant variety protection that is distinctness (D), uniformity (U), stability (S) (here in after called DUS), Novelty and Denomination, and some quality characteristics are used to examine the requirement of plant variety protection by each crops. OECD (Organization for Economic Cooperation Development) seed scheme regulates the seed certification for seed trade between countries. ISTA (International Seed Testing Association) and AOSA(Association for Official Seed Analyst) regulates the seed analysis standard and methods. Most of the countries in Europe has the National List system, which check the value for cultivation and use(VCU), that is to say, variety performance such as yield, quality and stress to environment. All the seeds should be enlisted in the National List before sell the seed in their country. All the quality characteristics checked variety performance are for instance, amylose and amylopectin content in rice, molting quality, $\beta$-glucan, protein in barley, protein and sugar content in soybean, sugar and amylopectin content in corn etc. Conditions for the protection of new variety of plant are DUS. Quality characteristics may be the important characteristics and used to check DUS in crop by crop. It is very important to develop a new characteristics and establish standard method fur examine the VCU and DUS test for each crop.

• The Korean Journal of Food And Nutrition
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• v.3 no.2
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• pp.149-160
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• 1990

The soybean $\beta$-amylase ($\alpha$-1, 4-glucan maltohydrolase, EC 3.2.1.2) is composed of seven isozymes(I', I, II, III, IV, V and VI), and isozyme II and IV are the main components among these. The Purification of $\beta$-amylase isozymes from soybean whey were performed by ammonium sulfate fractionation, CM-Sephadex C-50 column chromatography, DEAE-Sephadex chromatography and Gel filtration. The resulted purity of $\beta$-amylase was throughly confirmed by electrophoresis, and then determined its isoelectric point and molecular weight. The results obtained were as follows, 1. Five active fractions of soybean p-amylase were derived on CM-Sephadex C-50 column chromatography. 2. Seven active bands of p-amylase isozymes were detected by isoelectric focusing gel electrophoresis, and their isoelectric points(I' to VI) were 5.07, 5.15, 5.25, 5.40, 5.55, 5.70 and 5.93, respectively. 3. Isozyme II and IV were main components of soybean $\beta$-amylase. 4. The molecular weights of both isozyme II and IV were determined to be 56,000 daltons by the result of SDS polyacrylamide gel electrophoresis. 5. Km values of main isozyme II & IV for amylopectin were determined to be 2.25 mg/ml, which suggest the same function of each isozyme.

• Tuberculosis and Respiratory Diseases
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• v.83 no.2
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• pp.132-140
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• 2020

In human immunodeficiency virus (HIV)-infected patients, Pneumocystis jirovecii pneumonia (PCP) is a well-known opportunistic infection and its management has been established. However, PCP is an emerging threat to immunocompromised patients without HIV infection, such as those receiving novel immunosuppressive therapeutics for malignancy, organ transplantation, or connective tissue diseases. Clinical manifestations of PCP are quite different between patients with and without HIV infections. In patients without HIV infection, PCP rapidly progresses, is difficult to diagnose correctly, and causes severe respiratory failure with a poor prognosis. High-resolution computed tomography findings are different between PCP patients with HIV infection and those without. These differences in clinical and radiological features are due to severe or dysregulated inflammatory responses that are evoked by a relatively small number of Pneumocystis organisms in patients without HIV infection. In recent years, the usefulness of polymerase chain reaction and serum β-D-glucan assay for rapid and non-invasive diagnosis of PCP has been revealed. Although corticosteroid adjunctive to anti-Pneumocystis agents has been shown to be beneficial in some populations, the optimal dose and duration remain to be determined. Recent investigations revealed that Pneumocystis colonization is prevalent and that asymptomatic carriers are at risk for developing PCP and can serve as the reservoir for the spread of Pneumocystis by airborne transmission. These findings suggest the need for chemoprophylaxis in immunocompromised patients as well as infection control measures, although the indications remain controversial. Because a variety of novel immunosuppressive therapeutics have been emerging in medical practice, further innovations in the diagnosis and treatment of PCP are needed.

• Mycobiology
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• v.41 no.4
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• pp.171-176
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• 2013

Mushrooms are ubiquitous in nature and have high nutritional attributes. They have demonstrated diverse biological effects and therefore have been used in treatments of various diseases, including cancer, diabetes, bacterial and viral infections, and ulcer. In particular, polysaccharides, including ${\beta}$-glucan, are considered as the major constituents responsible for the biological activity of mushrooms. Although an overwhelming number of reports have been published on the importance of polysaccharides as immunomodulating agents, not all of the healing properties found in these mushrooms could be fully accounted for. Recently, many research groups have begun investigations on biologically active small-molecular weight compounds in wild mushrooms. In this mini-review, both structural diversity and biological activities of novel bioactive substances from Korean native mushrooms are described.