• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.75-81
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• 2018

Anonymity and privacy issues are becoming important as all transactions in the blockchain are open to users. Public blockchains appear to guarantee anonymity by using public-key addresses on behalf of users, but they can weaken anonymity by tracking with various analytic techniques based on transaction graph. In this paper, we propose a scheme to protect anonymity and privacy by converging various security techniques such as k-anonymity, mixing, blind signature, multi-phase processing, random selection, and zero-knowledge proof techniques with incentive mechanism and contributor participation. Through performance analysis, our proposed scheme shows that it is difficult to invade privacy and anonymity through collusion attacks if the number of contributors is larger than that of conspirators.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.6 no.1
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• pp.15-24
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• 1996

In this paper, we propose a new kind of signature scheme, called 'nominative signatures&, which is the dual scheme of undeniable signatures. Also we construct a zero-knowledge protocol that implements it. The new technique called 'nominative signatures' achieves these objectives: only nominee can verity the nominator(signer)'s signature and if necessary, only nominee can prove to the third party that the signature is issued to him(her) and is valid. Contraty to the undeniable signature scheme, nominative signatures are confirmed via a protocol between the nominee and the third party, so the cooperation of the nominee is necessary. That is, not a signer(nominator) but a verifier(nominee) can control the abuse of signatures - undeniable signature cannot be verified without the cooperation of the signer, so the signer controls the abuse of signatures. Our nominative signatures are very valuable for the case in which the content of signature is concerned with the verifier's privacy.

• Smart Media Journal
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• v.12 no.9
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• pp.95-102
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• 2023

As the utilization value of personal information increases, discussions on how to provide personal information are active, but information required by institutions to utilize personal information is being exposed more than necessary. Therefore, personal privacy protection is essential to overcome the problems and limitations of personal information protection. In this study, a decentralized identity information management model that overcomes the problems and limitations of the centralized identity management method of personal information and manages and selectively provides personal information by the information owner himself and demonstrates the excellence of personal information by implementing the Smart Personal Information Provision System (SPIPS) in the PBFT consensus algorithm through experiments.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.633-640
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• 2011

After Ganoderma lucidum was cultured in mushroom complete medium (MCM) supplemented with ginseng extract (GE), crude polysaccharide (GL-GE-CP) was fractionated from mycelium. Among GL-GE-CP from mycelium in MCM supplemented with 5, 10, and 15% GE (v/v ratio of MCM to GE), GL-GE-15-CP (15% GE) most significantly enhanced macrophage stimulation and intestinal immune system modulating activity compared with GL-CP in MCM without GE. When GL-GE-15-CP was further fractionated on DEAE-Sepharose CL-6B, GL-GE-15-CP-II displayed more potent activity than subfractions from GL-CP on macrophage stimulation, interleukin-12 production, and intestinal immune system modulation (1.75-, 5.68-, and 1.76-fold, respectively). Anti-metastasis effect against colon 26-M3.1 carcinoma cells was also enhanced by GL-GE-15-CP-II (72.8% inhibition). In addition, GL-GE-15-CP-II contained neutral sugar (83.00%) and uronic acid (9.11%), and consisted of Ara, Man, Gal and Glc (molar ratio of 0.39:0.50:0.75:1.00). Furthermore, GE supplementation helped to enhance the immunomodulation in G. lucidum, and it is assumed that neutral polysaccharides play an important role.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.655-662
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• 2013

The antioxidant and anticancer effects of the edible mushrooms Lentinus edodes (LE, Pyogo mushroom) and Agaricus blazei (AB, Agaricus mushroom), and the medicinal mushrooms Cordyceps militaris (CM, Dong chunghacho), Ganoderma lucidum (GL, Youngji mushroom), Inonotus obliquus (IO, Chaga mushroom), and Phellinus linteus (PL, Sangwhang mushroom) were studied in vitro. The bioactive components were extracted by methanol. The antioxidant effects were evaluated using the DPPH and hydroxyl radical scavenging assays. The antioxidant activities of medicinal mushrooms (35~90%) were higher than edible mushrooms (4~23%). The in vitro anticancer effects of the mushrooms were evaluated using the MTT assay in AGS gastric adenocarcinoma cells, HCT-116 colon carcinoma cells, and HepG2 hepatoma cells. The medicinal mushrooms CM, GL, IO, and PL showed 28~91% inhibition, while the edible mushrooms LE and AB exhibited 5~40% inhibition. The medicinal mushrooms, compared to edible mushrooms, effectively down-regulated the gene expression of the anti-apoptosis related gene Bcl-2 and inflammation-related genes iNOS and COX-2, and up-regulated the pro-apoptosis gene Bax (p<0.05). Total polyphenol and flavonoids contents of the medicinal mushrooms were 9.1~35.7 mg/g, while the edible mushrooms showed 0~13.3 mg/g. This study showed that antioxidant activities and anticancer activities in vitro increased in the order LE, AB, GL, CM, IO and PL. LE and AB showed the lowest effects among the samples, GL and CM had medium effects, and IO and PL exhibited the highest effects in the antioxidant and anticancer effect for three different human cancer cells. Taken together, PL resulted in the highest and LE the lowest effects in this study.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.27-35
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• 1988

In order to elucidate the systematic taxonomy and genetic characters of Canoderma lucidum, cultural characteristics of the fungus were investigated. Mycelial growth of Ganoderma lucidum were favorable on oat meal agar medium, and optimum temperature and pH of the medium for mycelial growth were $30^{\circ}C$ and 5.5-6.0 respectively. Irradiation of white fluorescent lamp inhibited mycelial growth and critical time for inhibition of mycelial growth was 4-8 hours. Concentric zones and mycelial strands of Ganoderma lucidum was induced by irradiation of white fluorescent lamp and formation of mycelial sectors was influenced by nutrient source of media and irradiation of white fluorescent lamp. These characters were different among the isolates, but no relationship was observed between these characters and the fruiting body type of the fungus. Basidiospores were formed directly from the mycelium cultured on artificial media without producing fruit body.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1346-1352
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• 2010

This study was conducted to investigate the antioxidant activities of the cultured ginseng with mushroom mycelia (Phellinus linteus (PL), Ganoderma lucidum (GL), and Hericium erinaceum (HE)) during cultivation periods of 10, 20, 30, 40, and 50 days. The lyophilized powder from the cultured ginseng with mycelia was extracted with 80% ethanol, and then evaluated for antioxidant activities. Total phenolic contents ranged from 149.63 to 205.91 mg/g, and the highest value was 80% EtOH extract from the cultured ginseng with GL at 30 days. The highest antioxidant activity ($IC_{50}$) for DPPH was 1.16 mg/mL in the cultured ginseng with HE at 40 days, and total antioxidant activity for ABTS was the highest value of 4.03 mg AA eq/g in PL cultivation at 30 days. $\alpha$-Glucosidase inhibitory activity was the highest value of 92.51% in EtOH extract from the cultured ginseng with PL at 50 days, and tyrosinase inhibitory activity was highest value of 13.21% in GL cultivation at 40 days. These results suggest that mushroom mycelium cultivation period for enhancement of antioxidant activity might be 40 days.

• The Korean Journal of Mycology
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• v.16 no.1
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• pp.21-25
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• 1988

This experiment was carried out to investigate proper conditions for protoplast isolation and reversion from Ganoderma lucidum and Gctnoderma sp.. In G. lucidum, 10 mg. $ml^{-1}$ Novozyme 234 with 0.6 M sucrose was proper for protoplast isolation. The optimal reaction time of mycelium with lytic enzyme was five hrs. Protoplast isolation from four-day-old mycelium was the most effective. Protoplast isolation from four-day-old mycelium in G. sp. was optimum in the combination of N ovozyme 234 and ${\beta}-glucuronidase$ with 0.6 M sucrose. MCM was suitable for reversion in G. lucidum while SCM was good for G. sp.. The most effective osmoticum stabilizer for protoplast reversion in G. lucidum and G. sp. was 0.6 M sucrose.

• Journal of Mushroom
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• v.12 no.4
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• pp.324-329
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• 2014

For evaluating the anti-allergy activity of mushrooms, forty two mushroom extracts were studied their inhibitory activities on the IgE-mediated degranulation in rat basophilic leukemia cell line (RBL-2H3 cell). Effects of mushroom extracts on the release of interleukin-4 (IL-4) and beta-hexosaminidase, and the cell viability of the IgE-sensitized were measured. From the analysis, five mushroom extracts such as the water extract from Flammulina velutipes (Curt.:Fr.) Sing showed the suppressive activities on IL-4 release as 20%. Eight extracts including the water extract of Ganoserma lucidum showed the suppressive activities on ${\beta}$-hexosaminidase release as 20%. Almost all of the extracts stimulated the proliferation of RBL-2H3 cell. The water extracts of Flammulina velutipes and Phellinus linteus were examined against the inhibitory activity in the production of IL-4 and ${\beta}$-hexosaminidase. Additionally, the extracts from Ganoserma lucidum, Isaria japonica, Phellinus linteus and Pleurotus ostreatus inhibited dose-dependently on ${\beta}$-hexosaminidase production. In conclusion, the result suggests that the mushrooms with the potent inhibitory efficacies on the degranulation of the mast cell would be candidate resources for the anti-allergy resources, and thus need to study for their utilization.

• Journal of Mushroom
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• v.13 no.4
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• pp.326-329
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• 2015

This study was carried out to anti-diabetic efficacy of alcoholic extracts in Ganoderma species and Phellinus Baumi. Ganoderma species and Phellinus Baumi. showed inhibitory activity of PTP1B, which acts as negative regulator of diabetes. The ${\alpha}-amylase$ is an important enzyme in the digestion of carbohydrates in the saliva and pancreatic. If inhibition of the enzyme Delaying the digestion rate of the carbohydrate can be reduced postprandial rise in blood glucose levels. The results of the tests the active level that showed a similar inhibition ${\alpha}-amylase$ inhibitory activity and a positive control. Phellinus Baumi. showed the inhibitory activity to 89%, Acarbose as positive control. ${\alpha}-glucosidase$ is an essential enzyme in the digestion and absorption of carbohydrates that break down carbohydrates into simple sugars polysaccharides. The results of the tests the active level that showed a low inhibitory activity. It is thought to be able to complement the shortcomings of conventional anti-diabetic drugs.