• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.652-655
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• 2005

This paper describes the development of an enzymatic assay system for the identification of inhibitors of isocitrate lyase (ICL), one of the key enzymes of the glyoxylate cycle that is considered as a new target for antifungal drugs. A 1.6 kb DNA fragment encoding the isocitrate lyase from Candida albicans ATCC10231 was amplified by PCR, cloned into a vector providing His-Patch-thioredoxin-tag at the N-terminus, expressed in Escherichia coli, and purified by metal chelate affinity chromatography. The molecular mass of the purified ICL was approximately 62 kDa, as determined by SDS-PAGE, and the enzyme activity was directly proportional to incubation time and enzyme concentration. The effects of itaconate-related compounds on ICL activity were also investigated. Among them, itaconic acid, 3-nitropropionate, and oxalate had strong inhibitory activities with $IC_{50}$ values of 5.8, 5.4 and $8.6\;{mu}g/ml$, respectively. These inhibitors also exhibited antifungal activity on YPD agar media containing acetate as a sole carbon source, albeit at high concentration. The results indicate that the C. albicans ICL may be a regulatory enzyme playing a crucial role in fungal growth and is a prime target for antifungal agents.

• Preventive Nutrition and Food Science
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• v.18 no.2
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• pp.104-110
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• 2013

Presence of Helicobacter pylori is associated with an increased risk of developing upper gastrointestinal tract diseases. Antibiotic therapy and a combination of two or three drugs have been widely used to eradicate H. pylori infections. Due to antibiotic resistant drugs, new drug resources are needed such as plants which contain antibacterial compounds. The aim of this study was to investigate the ability of GutGard$^{TM}$ to inhibit H. pylori growth both in Mongolian gerbils and C57BL/6 mouse models. Male Mongolian gerbils were infected with the bacteria by intragastric inoculation ($2{\times}10^9$ CFU/gerbil) 3 times over 5 days and then orally treated once daily 6 times/week for 8 weeks with 15, 30 and 60 mg/kg GutGard$^{TM}$. After the final administration, biopsy samples of the gastric mucosa were assayed for bacterial identification via urease, catalase and ELISA assays as well as immunohistochemistry (IHC). In the Mongolian gerbil model, IHC and ELISA assays revealed that GutGard$^{TM}$ inhibited H. pylori colonization in gastric mucosa in a dose dependent manner. The anti-H. pylori effects of GutGard$^{TM}$ in H. pylori-infected C57BL/6 mice were also examined. We found that treatment with 25 mg/kg GutGard$^{TM}$ significantly reduced H. pylori colonization in mice gastric mucosa. Our results suggest that GutGard$^{TM}$ may be useful as an agent to prevent H. pylori infection.

• Polymer(Korea)
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• v.33 no.3
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• pp.219-223
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• 2009

The nanofibers fabricated by using an electrohydrodynamic process has been used as various applications, such as nano-device, filtering system, protective clothes, wound dressing, and drug delivery system (DDS). Of these applications, the DDS should be needed to minimize side effects of drugs, maximize the properties of medicine, and efficiently deliver the required amount of drugs to the diseased area. In this paper, by using the electro spinning process, which is one of electrohydrodynamic processes, two different types, polycarprolactone and poly(ethylene oxide)/Rhodamine B, of electrospun mats were fabricated layer by layer and the release behavior of Rhodamine B was characterized with time. In addition, to show the feasibility of DDS of this type, we tested release behavior of a peptide of the nanofiber system, a PCL/(Peptide+PEO)/PCL nanofiber mat. The released peptide did not loss biological activities. From these results, we believe that the layered nanofiber mat as a DDS has enough function of a new drug delivery system.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.59-69
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• 2014

One of the major challenges in metabolic engineering for enhanced synthesis of value-added chemicals is to design and develop new strains that can be translated into well-controlled fermentation processes using bioreactors. The aim of this study was to assess the influence of various fed-batch strategies in the performance of metabolically engineered Pseudomonas putida strains, ${\Delta}gcd$ and ${\Delta}gcd-pgl$, for improving production of medium-chain-length polyhydroxyalkanoates (mcl-PHAs) using glucose as the only carbon source. First we developed a fed-batch process that comprised an initial phase of biomass accumulation based on an exponential feeding carbon-limited strategy. For the mcl-PHA accumulation stage, three induction techniques were tested under nitrogen limitation. The substrate-pulse feeding was more efficient than the constant-feeding approach to promote the accumulation of the desirable product. Nonetheless, the most efficient approach for maximum PHA synthesis was the application of a dissolved-oxygen-stat feeding strategy (DO-stat), where P. putida ${\Delta}gcd$ mutant strain showed a final PHA content and specific PHA productivity of 67% and $0.83g{\cdot}l^{-1}{\cdot}h^{-1}$, respectively. To our knowledge, this mcl-PHA titer is the highest value that has been ever reported using glucose as the sole carbon and energy source. Our results also highlighted the effect of different fed-batch strategies upon the extent of realization of the intended metabolic modification of the mutant strains.

• YAKHAK HOEJI
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• v.53 no.4
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• pp.228-234
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• 2009

Topoisomerase I (Topo I) participates in the DNA replication, transcription, and repair. Binding of Topo I inhibitor to the Topo I-DNA cleavage complex forms stabilized ternary complex which blocks DNA religation and ultimately causes cell death. Camptothecin (CPT) and its derivatives have been among the most effective anticancer drugs by inhibition of topo I. However, efforts to synthesize non-CPT drugs have been actively going on because the CPT derivatives have several limitations such as poor solubility, short half-life, and side effects. As an indenoisoquinoline, NSC314622 is not as potent as CPT, but its chemical stability and slower reversibility of the cleavage complex made it a good lead compound. Recently, a series of indenoisoquinoline analogues were synthesized with substituted dimethoxy or methylenedioxy on the aromatic ring and alkylamino on the lactam nitrogen. Some of them showed quite good Topo I inhibitory activity. Using the computer docking program, Surflex-Dock, indenoisoquinoline analogues were docked into the human Topo I-DNA cleavable complex. The docking results showed that the compounds with activity better than NSC314622 intercalated between the -1 and +1 base pairs at the cleavage site, but those with little or no activities did not appear to intercalate. These results could be useful to design new Topo I inhibitors improved than CPT.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.125-130
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• 2013

Influenza viruses cause significant morbidity and mortality in humans through epidemics or pandemics. Currently, two classes of anti-influenza virus drugs, M2 ion-channel inhibitors (amantadin and rimantadine) and neuraminidase inhibitors (oseltamivir and zanamivir), have been used for the treatment of the influenza virus infection. Since the resistance to these drugs has been reported, the development of a new antiviral agent is necessary. In this study, we examined the antiviral efficacy of the plant extracts against the influenza A/PR/8/34 infection. In vitro, the antiviral activities of the plant extracts were investigated using the cell-based screening. Three plant extracts, Thuja orientalis, Aster spathulifolius, and Pinus thunbergii, were shown to induce a high cell viability rate after the infection with the influenza A/PR/8/34 virus. The antiviral activity of the plant extracts also increased as a function of the concentration of the extracts and these extracts significantly reduced the visible cytopathic effect caused by virus infections. Furthermore, the treatment with T. orientalis was shown to have a stronger inhibitory effect than that with A. spathulifolius or P. thunbergii. These results may suggest that T. orientalis has anti-influenza A/PR/8/34 activity.

• Journal of Information Processing Systems
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• v.13 no.5
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• pp.1243-1258
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• 2017

A new medical materials scheduling system and its modeling method for the complex rescue are presented. Different from other similar system, first both the BeiDou Satellite Communication System (BSCS) and the Special Fiber-optic Communication Network (SFCN) are used to collect the rescue requirements and the location information of disaster areas. Then all these messages will be displayed in a special medical software terminal. After that the bipartite graph models are utilized to compute the optimal scheduling of medical materials. Finally, all these results will be transmitted back by the BSCS and the SFCN again to implement a fast guidance of medical rescue. The sole drug scheduling issue, the multiple drugs scheduling issue, and the backup-scheme selection issue are all utilized: the Kuhn-Munkres algorithm is used to realize the optimal matching of sole drug scheduling issue, the spectral clustering-based method is employed to calculate the optimal distribution of multiple drugs scheduling issue, and the similarity metric of neighboring matrix is utilized to realize the estimation of backup-scheme selection issue of medical materials. Many simulation analysis experiments and applications have proved the correctness of proposed technique and system.

• Journal of Pharmacopuncture
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• v.23 no.4
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• pp.212-219
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• 2020

Objectives: Nowadays cancer treatment is an important challenge in the medical world that needs better therapies. Many active secretions produced by insects such as honey bees used to discover new anticancer drugs. Bee venom (BV) has a potent anti inflammatory, anti cancer and tumor effects. The aim of present study is evaluation of anticancer effects induced by Apis mellifera venom (AmV) on cell Lines. Methods: AmV was selected for study on cancer cell lines. Total protein, molecular weight and LD50 of crude venom were determined. Then, cells were grown in Dulbecco's Modified Eagle medium supplemented with 10% fetal bovine serum and 1% antibiotics. The A549, HeLa and MDA-MB-231 cell Lines were exposed by different concentration of AmV. The morphology of cells was determined and cell viability was studed by MTT assay. Evaluation of cell death was determined by and DNA fragmentation. Results: The results from MTT assay showed that 3.125 ㎍/mL of A549, 12.5 for HeLa and 6.25 ㎍/mL of MDA-MB-231 killed 50% of cells (p < 0.05). Morphological analysis and the results from hoescht staining and DNA fragmentation indicated that cell death induced by AmV was significantly apoptosis. Conclusion: The data showed that using lower dosage of AmV during treatment period cause inhibition of proliferation in time and dose dependant manner. Findings indicated that some ingredients of AmV have anticancer effects and with further investigation it can be used in production of anticancer drugs.

• The Korea Journal of Herbology
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• v.34 no.2
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• pp.49-58
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• 2019

Objectives : Obesity is a public health concern associated with chronic diseases including hyperlipidemia, diabetes, fatty liver, atherosclerosis and cancer. As several anti-obesity drugs have been limited owing to their side effects, the development of new anti-obesity drugs through herbal medicines has been increasing. Cynanchum Wilfordii Radix (CW) traditionally is consumed for various health benefits including immune enhancing, anti-inflammation and anti-tumor activities. The aim of the present study is to evaluate the effects of CW on High fat diet (HFD)-induced obese mice. Methods : The mice were randomly divided into four groups (n=7). The mice were respectively fed a normal diet (ND), a high-fat diet (HFD), HFD plus CW (50 mg/kg/day), HFD plus CW (100 mg/kg/day). All groups were assayed for body weights, food efficiency ratio, blood biochemistry parameters, and organic tissue weights. Results : HFD-fed mice showed an increase in the body weight and serum biochemistry parameters levels (total cholesterol and triglycerides) as well as organic tissue weights. However, the administration of CW to obese mice induced a reduction in their body weight, food efficiency ratio, blood biochemistry parameters and weight of liver and fat compared with the HFD fed mice. Additionally, we observed that CW inhibited the lipid accumulation in liver and serum lipid parameter induced by HFD. Conclusions : Taken together, the findings of this study suggest that CW may be a potential agent for use in the treatment of obesity and obesity-related metabolic diseases.

• Journal of Ginseng Research
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• v.46 no.3
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• pp.337-347
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• 2022

Coronavirus disease 2019 (COVID-19) is currently a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 are directly associated with hyper-activation of innate immune response that excessively produce pro-inflammatory cytokines and induce cytokine storm, leading to multi-organ-failure and significant morbidity/mortality. Currently, several antiviral drugs such as Paxlovid (nirmatrelvir and ritonavir) and molnupiravir are authorized to treat mild to moderate COVID-19, however, there are still no drugs that can specifically fight against challenges of SARS-CoV-2 variants. Panax ginseng, a medicinal plant widely used for treating various conditions, might be appropriate for this need due to its anti-inflammatory/cytokine/viral activities, fewer side effects, and cost efficiency. To review Panax ginseng and its pharmacologically active-ingredients as potential phytopharmaceuticals for treating cytokine storm of COVID-19, articles that reporting its positive effects on the cytokine production were searched from academic databases. Experimental/clinical evidences for the effectiveness of Panax ginseng and its active-ingredients in preventing or mitigating cytokine storm, especially for the cascade of cytokine storm, suggest that they might be beneficial as an adjunct treatment for cytokine storm of COVID-19. This review may provide a new approach to discover specific medications using Panax ginseng to control cytokine storm of COVID-19.