• YAKHAK HOEJI
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• v.38 no.4
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• pp.425-429
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• 1994

The genuine aglycone, 20(S)-protopanaxadiol, obtained from the leaves of Panax ginseng as a result of direct alkaline treatment was isolated and characterized by spectroscopic evidences. The study on the yield of genuine aglycone which is produced from the treatment of some kinds of alkali was carried out. $Ginsenoside-Rh_2$ was synthesized by conjugation of 2,3,4,6-tetra-O-acetyl-${\alpha}$-D-glucopyranosyl bromide to 20(S)-protopanaxadiol in the presence of silver carbonate and cadmium cabonate. The preparation of $ginsenoside-Rh_2$ by this method is a new one which the yield of this saponin can be improved in the mild condition.

• Membrane Journal
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• v.30 no.3
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• pp.158-172
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• 2020

In the aspect of saving energy and water, facilitating the separation membrane for the water treatment has been rising recently as one of the possible solutions. However, microbial biofouling effect is the biggest obstacle that hinders reaching higher permeability over a prolonged period of nanofiltration operation. To solve this problem and fully utilize the filtration membranes with enhanced performance, largely two kinds of solutions are studied and the first and the most commonly mentioned type is the one using the silver nanoparticles. Since silver nanoparticles are important to be well tailored on membrane surface, various methods have been applied and suggested. Using silver nanoparticles however also has the drawbacks or possible toxicity risks, raising the need for other types of utilizing non silver particles to functionalize the membrane, such as copper, graphene or zinc oxides, and amine moieties. Each attempt included in either kind has produced some notable results in killing, preventing, or repelling the bacteria while at the same time, left some unsolved points to be evaluated. In this review, the effects of metal nanoparticles and other materials on the antifouling properties of water treatment membranes are summarized.

• Research in Plant Disease
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• v.17 no.2
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• pp.136-141
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• 2011

In other previous in vitro tests, the hyphal growth of Raffaelea quercivorus was inhibited by the treatments of various concentration of nano-silver. In this field tests, treatment of different concentrations of nano-silver to oak trees in Cheolwon and Hongcheon sites showed the inhibition effects against wilt disease caused by Raffaelea quercivorus. However, nano-silver-treated oak tree in Chuncheon site showed mild wilt symptoms with no phytotoxicity. Scanning electron microscope (SEM) observation confirmed that the spore and hypha of Raffaelea sp. inside the vessels were damaged by nano-silver. This result indicates the application of nanosilver is effective for control of Raffaelea quercivorus in the field.

• Journal of Veterinary Clinics
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• v.27 no.3
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• pp.252-256
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• 2010

Bovine mastitis, defined as an inflammation of the mammary gland, is usually associated with bacterial infection. Thus, treatment and control of mastitis relies primarily on antimicrobial therapy. This study investigated the bactericidal actions of silver ion against causing various bovine mastitis pathogens. Minimal inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and bactericidal activity times and concentrations of silver ion against pathogens were determined. The effect of silver ion on bacterial morphology was studied by scanning electron microscopy (SEM). The MICs and MBCs of silver ion for various bacteria strains ranged from 1.9-15.6 ${\mu}g$/ml. SEM images indicated formation of a pit, distortion and disruption of cell walls in silver treated Staphylococcus aureus and Escherichia coli. The results demonstrate that silver ion has a bactericidal capacity against causing various pathogens of bovine mastitis and suggest that silver ions may be exploitable as a therapeutic/preventative tool of bovine mastitis.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.3
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• pp.87-98
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• 2014

Objectives The present study aimed to investigate the effects of acupuncture and herbal external preparation on wound healing procedure in a deep partial thickness burn model in rats. Methods A total of 40 male Sprague-Dawley rats were allocated into four groups with an equal number in each group: acupuncture treatment group, herbal external perparation group, Silver sulfadiazine dressing group and control group. We describe the effect of acupuncture and herbal external preparation on morphologic and histologic changes, epithelial growth factor (EGF), hematological value of the deep partial thickness burn wound in rats. Results At 21th day after wounding the wound size in acupuncture treat group and herbal external preparation group were decreased more significantly compared to control group. In addition, epidermal regeneration on acupuncture treatment was than other treatment and control group in histological finding. Hematological findings revealed that acupuncture treatment group and herbal external prepartion group was more effective than control group in reducing inflammation response induced by burn. In acupuncture treated group, neutrophil and leukocyte level were significantly decreased compared to other treatment group. Also, this study showed that EGF was obviously expressed in nascent tissue when wounds were treated with the acupuncture and herbal external preparation after injury. In particular, acupuncture treatment group had a significant increase of EGF expression in burn wound healing area when compared with the other treatment groups. Conclusions These findings suggest that acupuncture and herbal external prepration may improve burn wound healing through decreasing inflammatory reaction, increasing tissue regeneration and expression of EGF. Moreover, acupuncture treatment could be more effective in comparison with Silver sulfadiazine dressing.

• Horticultural Science & Technology
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• v.33 no.3
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• pp.356-363
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• 2015

This study examined the effects of different day/night temperature regimes or silver ion on growth and flowering of passion fruit 'Tai-nung No.1'. Low temperature treatment ($20/15^{\circ}C$) caused passion fruit cultivar 'Tai-nung No.1' to fail to flower. Flowering induction occurred within a temperature range of $20-30^{\circ}C$, with no significant difference in the days to first flower bud and the total number of flower buds between plants grown at $30/25^{\circ}C$ and $25/20^{\circ}C$. However, plants grown at $30/25^{\circ}C$ exhibited their first flower buds set on the higher nodes and had higher abortion rates of flower buds than those at $25/20^{\circ}C$. Plants grown at $30/25^{\circ}C$ had the most rapid growth and the shortest plastochron. We also evaluated the effect of the ethylene response inhibitors silver nitrate ($AgNO_3$) and silver thiosulfate (STS) on growth and flowering of potted passion fruit 'Tai-nung No.1', when they were exposed to low temperature conditions ($20/15^{\circ}C$) following chemical treatments ($AgNO_3$ or STS, at 0.5 or 1.0 mM). $AgNO_3$ and STS treatments induced flower formation and initial flower bud formation within approximately two weeks at $20/15^{\circ}C$ whereas non-treated control plants exhibited no flower formation. ACC content and activity of ACC oxidase in the leaves of passion fruit 'Tai-nung No.1'exposed to low temperature conditions ($20/15^{\circ}C$) were significantly inhibited by the ethylene inhibitor treatments. These results indicate that ethylene, which is produced under low temperature conditions, plays an important role in inhibiting flower formation in passion fruit.

• Fashion & Textile Research Journal
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• v.6 no.4
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• pp.503-510
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• 2004

The study is one of fundamental researches for the development of future smart clothing and textile products with blocking properties from electromagnetic waves by analyzing human physical symptoms in using electromagnetic products in such an environments. Among various textiles in the experiment, nano silver has shown the best blocking performance from electromagnetic waves, which decreases depending on the distance. The power spectrum distribution and the incidence of electroencephalogram between blocking materials and aural stimuli has shown that, ${\beta}$, wave appeared to be active in all channels except for $T_4$, whereas all waves appeared with processed materials and especially with nano silver silk(NSS), ${\alpha}$, ${\beta}$, ${\theta}$, ${\gamma}$ waves appeared active in all regions. As for the brain mapping of ${\alpha}$ wave according to time, there found a strong activity in $P_3$, $P_4$ of the parietal lobe, with all materials on all time regions. With silk nylon metal(SNM) and NSS, it appeared strong in $F_3$, $F_4$ as well. As for ${\beta}$, wave, the activity appeared strong in frontal lobe before 7min. 30sec, where it tends to diminish abruptly in 7min. 30sec. to 13min. 30sec. region. After 13min., it regained gradually. With NSS, it appeared strong in all areas except for the farthest $T_4$. The appearance of ${\nu}$ wave can be deduced as it can affect human body with its toxic property while the silver particles become nano-sized. Therefore, the study conducted with human participants requires a proper particle size of it which would not penetrate cellular tissues and a proper binder and binding treatment for it, to prevent the physical fatigues and the potential diseases. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

• Journal of Korean Foot and Ankle Society
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• v.10 no.2
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• pp.250-254
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• 2006

Purpose: The treatment of diabetic foot ulcers with total contact cast has been reported to be associated with numerous undesirable complications. This study shows that our technique of total contact casting that incorporates high concentration silver coated foam dressing. Materials and Methods: Forty-four diabetic foot ulcers were treated with total contact cast along with high concentration silver coated foam dressing. Complication and healing rates were evaluated. Results: Eighty five percent of the ulcers healed within 6 weeks with an overall complication rate of 7%. There were only two cases (5%) of infection and no recurrent ulceration and no another site new pressure ulcer in our study. Conclusion: Total contact casting incorporates high concentration silver coated foam dressing resulted in fewer complications rate and healing rate that is comparable to other studies.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.701-709
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• 1992

Silver particles were impregnated on carbon black with colloidal method and used as catalyst for oxygen electrode in alkaline fuel cell. With the addition of sodium dodecylbenzenesulfonate in $AgNO_3$ and $NaBH_4$solution, colloidal solution was made and confirmed with electrophoresis test. Effects of particle size on electrode performance were studied and $200{\AA}$ of silver particle size shown the highest value of mass activity. The aggromeration of silver particle was Influenced with surfactant amount, stirring time and heat treatment. Considering the increase of particle size caused of operating temperature, recommendable particle size of silver catalyst for manufacturing the electrode was $100{\AA}$. Dispersity of carbon black was investigated and reagglomeration was appeared after homogenizing 30 sec.

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.3
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• pp.127-141
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• 2015

Silver-based systems activated by low intensity direct current continue to be investigated as an alternative antimicrobial for infection prophylaxis and treatment. However there has been limited research on the quantitative characterization of the antimicrobial efficacy of such systems. The objective of this study was to develop a semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model providing the quantitative relationship between the critical system parameters and the degree of antimicrobial efficacy. First, time-kill curves were experimentally established for a strain of Staphylococcus aureus in a nutrientrich fluid environment over 48 hours. Based on these curves, a modified PK/PD model was developed with two components: a growing silver-susceptible bacterial population and a depreciating bactericidal process. The test of goodness-of-fit showed that the model was robust and had good predictability ($R^2>0.7$). The model demonstrated that the current intensity was positively correlated to the initial killing rate and the bactericidal fatigue rate of the system while the anode surface area was negatively correlated to the fatigue rate. The model also allowed the determination of the effective range of these two parameters within which the system has significant antimicrobial efficacy. In conclusion, the modified PK/PD model successfully described bacterial growth and killing kinetics when the bacteria were exposed to the electrically activated silver-titanium implant system. This modeling approach as well as the model itself can also potentially contribute to the development of optimal design strategies for other similar antimicrobial systems.