• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.163-165
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• 2004

• Journal of Periodontal and Implant Science
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• v.28 no.1
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• pp.145-160
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• 1998

The ultimate goal of periodontal therapy is the regeneration of periodontal tissue which has been lost due to destructive periodontal disease, and numerous kinds of materials and techniques have been developed to achieve this goal. Bone grafts include autografts, allografts, xenografts and synthetic grafts. Among the synthetic grafts, bioactive glass has been used in dentistry for more than ten years and Fetner reported improved new bone formation and more amount of new attachment after grafting PerioGlas, a kind of bioactive glass, in 2-wall defects of monkeys in 1994. It Is well known that 1-wall defects have less osteogenic potential and more epithelial migration, so we need to study the erect of bioactive glass in 1-wall dejects in dogs. The present study evaluates the effect of bioactive glass on the epithelial migration, alveolar bone regeneration, cementum formation and gingival connective tissue attachment in intrabony detects of dogs. Four millimeter deep and four millimeter wide 1-wall defects were surgically cheated in the mesial aspects of premolars. The test group received bioactive glass with a flap procedure and the control underwent flap procedure only. Histologic analysis after 8 weeks of healing revealed the following results: 1. The height of gingival margin was 1.30{\pm}0.73mm$ above CEJ in the control and $1.40{\pm}0.78mm$ in the test group. There was no statistically significant difference between the two group. 2. The length of epithelial growth (the distance from CEJ to the apical end of JE) was $1.74{\pm}0.47mm$ in the control and $1.12{\pm}0.36mm$ in the test group. These was a statistically significant difference between the two groups (P<0.01). 3. The length of new cementum was $2.06{\pm}0.73mm$ in the control and $2.62{\pm}0.37mm$ in the test group. There was no statistically significant difference between the two groups. 4. The length of new bone was $1.83{\pm}0.74mm$ in the control and $2.39{\pm}0.59mm$ in the test group. There was no statistically significant difference between the two groups. These results suggest that the use of bioactive glass 1-wall intrabony defects has significant effect on the prevention of junctional epithelium migration, but doesn't have any significant effect on new bone and new cementum formation.

• Journal of Microbiology and Biotechnology
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• v.25 no.5
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• pp.629-636
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• 2015

Chemical investigation of the actinobacterial isolate Pseudonocardia endophytica VUK-10 has led to the segregation of two known bioactive compounds, namely 4-(2-acetamidoethyl) phenyl acetate and 4-((1, 4-dioxooctahydropyrrolo [1, 2-a] pyrazin-3-yl) methyl) phenyl acetate. The strain was isolated from a sediment sample of the Nizampatnam mangrove ecosystem, south coastal Andhra Pradesh, India. The chemical structure of the active compounds was established on the basis of spectroscopic analysis, including ¹H NMR and ¹³C NMR spectroscopies, FTIR, and EIMS. The antimicrobial and cytotoxic activities of the bioactive compounds produced by the strain were tested against opportunistic and pathogenic bacteria and fungi and on MDA-MB-231, OAW, HeLa, and MCF-7 cell lines. The compounds exhibited antimicrobial activities against gram-positive and gram-negative bacteria and fungi and also showed potent cytotoxic activity against MDA-MB-231, OAW, HeLa, and MCF-7 cell lines. This is the first example for this class of bioactive compounds isolated from Pseudonocardia of mangrove origin.

• Journal of Technologic Dentistry
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• v.25 no.1
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• pp.21-28
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• 2003

The purpose of this study was to process bio-active glass ceramic composite, reinforced with sapphire fibers, by hot press. Also to study the interface of the matrix and the sapphire fiber, and the mechanical properties. Glass raw materials melted in Pt crucible at 1300$^{\circ}C$ during 3.5 hours. The melt was crushed in ball mill and then crushed material, ground and sieved to $<40{\beta}{\mu}m$. Sapphire fibers cut (30mm) and aligned. Powder and fibers hot pressed. The micrographs show good bonding between the matrix and the fiber and no porosity in the glass matrix. This means ideal fracture phenomena. Glass is fractured before the fiber. This is indication of good fracture strength. EDXS showing aluminum rich phase and crystalline phase. Bright field image of the matrix showing crystalline phase. Also diffraction pattern of TEM showing the crystalline phase and more than one phase. Strength of the samples was determined by 3 point bend testing. Strength of the 10vol% sample was approximately 69MPa, while strength of the control sample is 35MPa. Conclusions through this study as follow: 1. Micrographs show no porosity in the glass matrix and the interface. 2. The interface between the fiber and the glass matrix show no gaps. 3. Fracture of the glass indicates characteristic fiber-matrix separation. 4. Presence of crystalline phase at high processing temperature. 5. Sapphire is compatible with bioactive glass.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.2
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• pp.76-80
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• 2013

For further improvement of osseo-integration of bone crystal with a dental implant, a design optimization study is carried out for various holes inside its body to deliver bioactive materials and the effect of bioactive material injection on the bone crystal growing. When bioactive material is absorbed, the bone crystal can grow into holes, which would increase the strength of implant bonding as well as a surface integration. The stress concentrations near the uppermost outlet holes were reduced with increasing the number of outlet holes. A design improvement in the uppermost outlet was shown to be effective in reducing the stress concentration. For design parameters under consideration in this study, total area of outlet of 6.38 $mm^2$ and maximum stress of 1.114 MPa, which corresponds to type 6-C. It is due to the minimization of maximum stress and total area of outlet. The design of the outlet facing down was more effective in reducing the maximum stress value compared with a horizontal symmetry.

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.761-764
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• 2009

Ag-Doped bioactive ceramic composites were prepared by colloidal silver solution. The physical properties of colloidal silver solution and Ag-Doped bioactive ceramic composites were characterized by Scanning electron microscopy(SEM), X-Ray Diffractometer(XRD) and Raman spectrophotometer respectively. According to XRD, we have identified that the chloride ion was chemically attached silver nano particles. SEM studies showed that silver chloride phases were homogeneously distributed on the Ag-Doped bioactive ceramic composites surface. Finally, we concluded that the silver chloride phase on the Ag-Doped bioactive ceramic composites surface was strongly prevent formation of Ag-hydroxyapatite.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.201-209
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• 2021

Agarwood (Aquilaria spp) has high economic value. However, essential oil production from agarwood is a time-consuming process. Additionally, agarwood leaves have not been utilized even though they contain various bioactive ingredients. In this study, agarwood leaves were fermented using Lactobacillus plantarum ATCC 8014 with or without Stevia (4, 8, and 12%; v/v). The fermented fluid was mixed with maltodextrin (15%; w/v) and subjected to spray drying (inlet temperature, 120℃; outlet temperature, 65-70℃). The contents of polyphenols, polysaccharides, saponins, and flavonoids and the viability of L. plantarum were determined. Fermentation enhanced the levels of bioactive compounds. The contents of polyphenol (69.19 ± 4.05 mg GAE/g of sample), polysaccharide (20.75 ± 0.98 mg GE/g of sample), saponin (305.23 ± 4.21 mg OAE/g of sample), and flavonoid (7.86 ± 0.72 mg QE/g of sample), and the viability of L. plantarum (8.72 ± 0.17 log CFU/ml) were markedly upregulated in the samples containing Stevia (12%; v/v). This indicated that the supplementation of Stevia during fermentation decreases the fermentation time (9 h), upregulates bioactive compound production in agarwood leaves, enhances microencapsulation during spray drying, and increases the viability of L. plantarum under simulated gastric digestion conditions.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.731-738
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• 2019

Endophytic fungi are an important component of plant microbiota, and have the excellent capacity for producing a broad variety of bioactive metabolites. These bioactive metabolites not only affect the survival of the host plant, but also provide valuable lead compounds for novel drug discovery. In this study, forty-two endophytic filamentous fungi were isolated from Ficus elastica leaves, and further identified as seven individual taxa by ITS-rDNA sequencing. The antimicrobial activity of these endophytic fungi was evaluated against five pathogenic microorganisms. Two strains, Fes1711 (Penicillium funiculosum) and Fes1712 (Trichoderma harzianum), displayed broad-spectrum bioactivities. Our following study emphasizes the isolation, identification and bioactivity testing of chemical metabolites produced by T. harzianum Fes1712. Two new isocoumarin derivatives (1 and 2), together with three known compounds (3-5) were isolated, and their structures were elucidated using NMR and MS. Compounds 1 and 2 exhibited inhibitory activity against Escherichia coli. Our findings reveal that endophytic fungi from the rubber tree F. elastica leaves exhibit unique characteristics and are potential producers of novel natural bioactive products.

• Clean Technology
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• v.30 no.3
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• pp.195-202
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• 2024

Plant polyphenols have attracted attention recently because of their abundance in the human diet, high antioxidant effects, and ability to prevent various diseases associated with oxidative stress, such as cancer and cardiovascular and neurodegenerative diseases. Therefore, this study demonstrated the extraction of bioactive phenolic compounds from Allium hoorkei root (AHR) using subcritical water extraction (scWE) under various temperatures (120 ~ 160 ℃) and times (30 ~ 180 min) at a fixed pressure (10 MPa) and AHR to water ratio (1:20, w/w). Furthermore, this study used severity factors, the combined effect of the temperature and time, in order to optimize the conditions for achieving a high yield and efficient recovery of target bioactive phenolic compounds while minimizing the degradation of the extracted products and maintaining a high selectivity. Subcritical water extraction at 160 ℃ for 30 min (severity of 3.24) produced a relatively high yield (88%) and high number of bioactive compounds including total phenolic contents (31.3 mg GAE/g dry AHR) and rare sugars (D-picose, D-talose, and D-tagatose) compared to Soxhlet extracts obtained from extraction for 8 h with water and 75% ethanol. As a result, the extracts obtained from the green scWE process may have high potential applications in medicines and functional foods because of their high bioactivity and safety.

• Journal of Mushroom
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• v.6 no.1
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• pp.1-12
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• 2008

Mushroom is well known for a safe food for a long time and, what is more, has a lot of useful characteristics related on the pharmacological activities. It is expected to be one of the most important functional food due to its diverse bioactive compounds. Especially, medical potentiality on immunomodulator and antitumor continues to be focused. Recent research trend and commercialization of functional healthy food using mushroom and its bioactive compounds will be herein introduced. Industrialization of mushroom functional substances will be also discussed.