• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.801-806
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• 2002

A multiplex competitive polymerase chain reaction (PCR) method was developed for the rapid identification and quantification of Leuconostoc mesnteroides and Lactobacillus plantarum populations which are the key microorganisms in kimchi fermentation. The strain-specific primers were designed to selectively amplify the target genes encoding 165 rRNA of L. plantarum and dextransucrase of L. mesenteroides. There was a linear relationship between the band intensity of PCR products and the number of colony forming units of each model organism. The PCR quantification method was compared with a traditional plate-counting method f3r the enumeration of the two lactic acid bacteria in a mixed suspension culture and also applied to a real food system, namely, watery kimchi. The population dynamics of the two model organisms in the mixed culture were reliably predictable by the competitive PCR analysis.

• Fisheries and Aquatic Sciences
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• v.21 no.8
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• pp.22.1-22.7
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• 2018

Background: Apoptosis is a process of programmed cell death, and apoptosis defect results in serious diseases such as cancer. Apoptosis induction is one of the key mechanisms of anti-cancer agents. This study was aimed to find anti-prostate cancer compounds from marine-derived fungus Microsporum sp. Results: We found that physcion isolated from the fermentation broth extract of the marine fungus Microsporum sp. strain MFS-YL decreases the cell proliferation of PC3 human prostate cancer cells. Physcion induced cell apoptosis as determined by Annexin V/propidium iodide double staining. Physcion downregulated the anti-apopotoic proteins such as Ras, Bcl-xL, and Bcl-2, whereas upregulated the pro-apoptotic Bax. Physcion also activated caspase-3, caspase-8, and caspase-9. Conclusion: These results suggest that physcion from Microsporum sp. inhibits the proliferation of PC3 human prostate cancer cells via the pathway leading to apoptotic cell death. Physcion may be a potential candidate in the field of anticancer drug discovery against human prostate cancer.

• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.309-319
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• 2009

Transgenic plant cell cultures for the production of biopharmaceuticals including monoclonal antibodies, recombinant proteins have been regarded as an alternative platform in addition to traditional microbial fermentation and mammalian cell cultures. Plant-made pharmaceuticals (PMPs) have several advantages such as safety, cost-effectiveness, scalability and possibility of complex post-translational modifications. Increasing demand for the quantity and diversity of pharmaceutical proteins may accelerate the industrialization of PMP technology. Up to date, there is no plant-made recombinant protein approved by USFDA (Food and Drug Administration) for human therapeutic uses due to the technological bottlenecks of low expression level and slight differences in glycosylation. Regarding expression levels, it is possible to improve the productivity by using stronger promoter and optimizing culture processes. In terms of glycosylation, humanization has been attempted in many ways to reduce immune responses and to enhance the efficacy as well as stability. In this review article, all these respects of transgenic plant cell cultures were summarized. In addition, we also discuss the general characteristics of plant cell suspension cultures related with bioreactor design and operation to achieve high productivity in large scale which could be a key to successful commercialization of PMPs.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.902-908
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• 2018

Optimization of the culture medium to maximize menaquinone-7 (MK-7) production by Bacillus subtilis strain KCTC 12392BP in static culture was carried out using statistical experimental methods, including one factor at a time, fractional factorial design, and response surface methodology (RSM). Maltose (carbon source), tryptone (nitrogen source), and glycerol (activator) were identified as the key medium components for MK-7 synthesis by the fractional factorial design, and were selected for statistical optimization by RSM. The statistical analysis indicated that, in the range that was studied, maltose, tryptone, and glycerol were all critical factors having profound effects on the production of MK-7, with their coefficients for linear and quadratic all significant at the p < 0.05 level. The established model was efficient and feasible, with a determination coefficient ($R^2$) of 0.9419. The predicted concentrations of maltose, tryptone, and glycerol in the optimal medium were determined as 36.78, 62.76, and 58.90 g/l, respectively. In this optimized medium, the maximum yield of MK-7 reached a remarkably high level of $71.95{\pm}1.00{\mu}g/ml$ after 9 days of static fermentation, which further verified the practicability of this optimized strategy.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.75-88
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• 2001

In this paper, the microbial production of riboflavin is reviewed and includes descriptions of riboflavin overproducers, and the biosynthesis and details of the key-enzyme genes related to riboflavin. There kinds of riboflavin overproducers are known; Bacillus subtilis and Candida famate utilize glucose as a carbon source, but the fungus Ashbya gossypii requires plant oil as its sole carbon source. The starting material in ribofalvin biosynthesis is guanosine triphospate (GTP), which is converted to riboflavin through six enzymatic reactions. Though Bacillus subtilis, Candida famate, and Ashbya gossypii operate via different pathways until GTP, they follow the same pathway from GTP to riboflavin. From the metabolic viewpoint, with respect to improved riboflavin production, the supplementation of GTP, aprocess-limiting precursor must be considered. The GTP fluxes originate from three sources, serine, threonine and glyoxylate cycles. The development of pathways to strengthen GTP supplementation using biotechnological techniques remains an issue fro future research.

• Korean Journal of Microbiology
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• v.9 no.1
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• pp.1-26
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• 1971

Intensive taxonomical studies of the Aspergilli have long been made. Altogether 132 species and 18 varieties are recognized in the book "The Genus Aspergillus" written by Raper and Fennell (1965), in contrast to 77 species, 8 varieties and 4 mutations in " A Manual of Aspergilli" written 20 years earlier by Thom and Raper (1945). Classification of the Asperilli by Thom and Raper (1945) and by Raper and Fenell (1965). Classification of the Aspergilli by Thom and Raper (1945) and by Rapher and Fenell (1965) have been based mainly upon morphological and cultural detail both physiological and biochemical activities. In Korean there are many kinds of foods fermented natrually without the employment of selected microorganisms, and there are, of course, many different microorganisms serving in the fermentation fermented foods than other countries, the distribution and biological properties of the Asperigilli, in Korea are more variable. Taxonominical studies with 36 strains of Asperilli were based upon the examinations of morphological, cultural, and physiological characteristics. nineteen strains indigenous to Korea were selected from a lot of strains which had been isolated from meju and kokja and one strain from soil. They were identified according to the group key of Raper and Fennell. Ten strains were donated by Dr.Hesseltine of the Northern Utilization Research and Development Division in the U.S.A. From the Asp. japonicus supplied by Dr.Hesseltine, a white mutant was isolated and also studied. Two strains were donated by Dr. Murakami of the Research Institute of Brewing in Japan, and four strains came from Korean industrial companies.ndustrial companies.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.487-496
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• 2021

Microalgae is one of the promising biodiesel feedstock with high growth rates compared to those of terrestrial oil crops. Despite its numerous advantages, biodiesel production from microalgae needs to reduce energy demand and material costs further to go to commercialization. During solvent extraction of microalgal lipids, lipid-extracted algae (LEA) cell residue is generated as an organic solid waste, about 80-85% of original algal biomass, and requires an appropriate recycling or economic disposal. The resulting LEA still contains significant amount of carbohydrates, proteins, N, P, and other micronutrients. This review will focus on recent advancement in the utilization of LEA as: (i) utilization as nutrients or carbon sources for microalgae and other organisms, (ii) anaerobic digestion to produce biogas or co-fermentation to produce CH₄ and H₂, and (iii) conversion to other forms of biofuel through thermochemical degradation processes. Possible mutual benefits in the integration of microalgae cultivation-biodiesel production-resulting LEA with anaerobic digestion and thermochemical conversion are also discussed.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.256-267
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• 2019

The use of low-cost substrates represents one key issue to make single cell oil production sustainable. Among low-input crops, Arundo donax L. is a perennial herbaceous rhizomatous grass containing both C5 and C6 carbohydrates. The scope of the present work was to investigate and optimize the production of lipids by the oleaginous yeast Cutaneotrichosporon curvatus from undetoxified lignocellulosic hydrolysates of steam-pretreated A. donax. The growth of C. curvatus was first optimized in synthetic media, similar in terms of sugar concentration to hydrolysates, by applying the response surface methodology (RSM) analysis. Then the bioconversion of undetoxified hydrolysates was investigated. A fed-batch process for the fermentation of A. donax hydrolysates was finally implemented in a 2-L bioreactor. Under optimized conditions, the total lipid content was 64% of the dry cell weight and the lipid yield was 63% of the theoretical. The fatty acid profile of C. curvatus triglycerides contained 27% palmitic acid, 33% oleic acid and 32% linoleic acid. These results proved the potential of lipid production from A. donax, which is particularly important for their consideration as substitutes for vegetable oils in many applications such as biodiesel or bioplastics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.11
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• pp.1695-1700
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• 2014

Oriental herbal liquor (Yakju) is a type of Korean traditional alcoholic beverage that uses Nuruk and oriental herbs for fermentation. The purpose of this study was to develop cosmetic ingredients using Jubak, which is a by-product of alcoholic fermentation of oriental herbal liquor. To investigate antioxidant, whitening, and anti-aging effects of Jubak, we prepared extract of Jubak and its solvent fractions. Ethyl acetate fraction (KSD E4-3) showed the most prominent free radical [1,1-diphenyl-2-picrylhydrazyl (DPPH)] scavenging activity ($SC_{50}$: 0.75 mg/mL). KSD E4-3 significantly inhibited in vitro mushroom tyrosinase activity ($IC_{50}$: 0.82 mg/mL) and reduced the melanin contents in mouse melanoma melanocyte, B16F10 cells. KSD E4-3 down-regulated protein expression of tyrosinase related proteins (TRP)-1, -2, which play key roles in melanogenesis. For anti-aging effects, inhibition of matrix metalloproteinase (MMPs) expression was evaluated using human keratinocyte, HaCaT cells. Treatment of HaCaT cells with KSD E4-3 reduced expression of MMP-1, -2, -9 and inhibited proteolytic activities of MMP-2, -9. These results suggest that KSD E4-3 induces down-regulation of cellular melanogenesis and protects against photoaging induced by UVB-induced damage. Thus KSD E4-3 could potentially be a valuable cosmetic ingredient.

• Food Engineering Progress
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• v.22 no.4
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• pp.337-343
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• 2018

Coffee is a commonly consumed beverage that contains anti-inflammatory compounds such as caffeine, chlorogenic acid, cafestol, trigonelline, and kahweol. Lactobacillus plantarum is a lactic acid bacterium most frequently used in the fermentation of food products of plant origin. L. plantarum is able to degrade some food phenolic compounds and provide high value-added compounds such as powerful antioxidants or food additives approved as flavouring agents. In this study, we investigated the anti-inflammatory effects of coffee extract fermented by L. plantarum on RAW264.7 macrophages. In lipopolysaccharide-stimulated RAW264.7 cells, these coffee extracts exhibited anti-inflammatory activities through the reduction of nitric oxide (NO) production and inducible NO synthase expression. Fermented coffee extracts significantly decreased the expression of inflammatory cytokines such as tumor necrosis factor ${\alpha}$, interleukin $1{\beta}$, interleukin 6, and interferon ${\gamma}$. Cyclooxygenase-2, which is one of the key biomarkers for inflammation, was significantly suppressed. These results might be helpful for understanding the anti-inflammatory mechanism of fermented coffee extract on immune cells and, moreover, suggest that fermented coffee extract may be a beneficial anti-inflammatory agent.