• KSBB Journal
• /
• v.14 no.5
• /
• pp.628-632
• /
• 1999

Optimization of the medium and fermentation conditions for erythritol production has been studied. We have found that the optimal carbon source was glucose at the concentration of 400 g/L. The optimal temperature was 3$0^{\circ}C$ with excessive aeration. Improved erythritol productivity was achieved by reducing the yeast extract from 5 g/L to 3g/L while adding 2.7 g/L urea, 1.79g/L $K_2HPO_4, and 0.18g/L MgSO$_4$. 7$H_2O. The erythritol productivity increased from 0.747 g/L/h to 1.071 g/L/h and the yield increased from 31.4% to 45.2%. The byproduct glycerol was reduced from 96.6g/L to 45.7g/L as well. We have performed 5L fermentation with and without the pH control. The erythritol productivity with the pH control was about 30% lower than that without pH control. Excessive foaming of 5L fermentation has been observed during fermentation.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.8
• /
• pp.1230-1239
• /
• 2010

Five bacterial species, capable of degrading the recalcitrant organic compounds (ROCs) diethyleneglycol monomethylether (DGMME), 1-amino-2-propanol (APOL), 1-methyl-2-pyrrolidinone (NMP), diethyleneglycol monoethylether (DGMEE), tetraethyleneglycol (TEG), and tetrahydrothiophene 1,1-dioxide (sulfolane), were isolated from an enrichment culture. Cupriavidus sp. catabolized $93.5{\pm}1.7$ mg/l of TEG, $99.3{\pm}1.2$ mg/l of DGMME, $96.1{\pm}1.6$ mg/l of APOL, and $99.5{\pm}0.5$ mg/l of NMP in 3 days. Acineobacter sp. catabolized 100 mg/l of DGMME, $99.9{\pm}0.1$ mg/l of NMP, and 100 mg/l of DGMEE in 3 days. Pseudomonas sp.3 catabolized $95.7{\pm}1.2$ mg/l of APOL and $99.8{\pm}0.3$ mg/l of NMP. Paracoccus sp. catabolized $98.3{\pm}0.6$ mg/l of DGMME and $98.3{\pm}1.0$ mg/l of DGMEE in 3 days. A maximum $43{\pm}2.0$ mg/l of sulfolane was catabolized by Paracoccus sp. in 3 days. When a mixed culture composed of the five bacterial species was applied to real wastewater containing DGMME, APOL, NMP, DGMEE, or TEG, 92~99% of each individual ROC was catabolized within 3 days. However, at least 9 days were required for the complete mineralization of sulfolane. Bacterial community diversity, analyzed on the basis of the TGGE pattern of 16S rDNA extracted from viable cells, was found to be significantly reduced in a conventional bioreactor after 6 days of incubation. However, biodiversity was maintained after 12 days of incubation in an electrochemical bioreactor. In conclusion, the electrochemical reduction reaction enhanced the diversity of the bacterial community and actively catabolized sulfolane.

• Microbiology and Biotechnology Letters
• /
• v.1 no.2
• /
• pp.105-113
• /
• 1973

The effect of biotin and biotin vitamer on the fermentative production of L-glutamic acid (L-GA) by Brevibacterium flavum was studied. And results were as follows. 1) L-GA production in the medium containing 10％ Glucose was the best at the concentration of Biotin 5${\gamma}$/l, Desthiobiotin 5${\gamma}$/1, and 7,8-Diaminopelargonic acid 10${\gamma}$/1, respectively. 2) In the experiment using the Glucose-Acetate mixed media derided into four parts, considerable amounts of cell growth and L-GA production were observed in the mixed medium containing 2％ Glucose-Acetate. 3) In the cases of using the media containing methanol, ethanol, ethylacetate, acetic acid (free acetate), Na-acetate:NH$_4$-acetate=2 : 1, the production of L-GA were in decreasing order as follows; Na-Acetate:NH-Acetate=2 : 1> Acetic acid (free acetate)> Ethylacetate> Ethanol＞ Methanol. 4) When biotin vitamers as growth factors were added in the medium containing Glucose or Acetate as the source of carbon, the substitution effect of Desthiobiotin was almost the same, 7,8-Diaminopelargonic acid 3 or 4 times stronger, and Bisnorbiotin has no substitution effect, compared with Biotin.

• KSBB Journal
• /
• v.19 no.5
• /
• pp.352-357
• /
• 2004

Human ferritin H- and L-chain genes (hfH and hfL) were cloned into the yeast shuttle vector YEp352 containing the GAL1 (galactokinase) and GAL10 (epimerase) divergent promoters and the vectors constructed were used to transform Saccharomyces cerevisiae 2805. SDS-PAGE displayed expression of the introduced hfH and hfL in both recombinant strains of Y1H10L and Y1L10H. The ferritin subunits, that represented ca. $22\%$ and $15\%$ of the soluble proteins in Y1H10L and Y1L10H, were spontaneously assembled into active ferritin heteropolymers. The H subunit content of the purified recombinant human ferritin heteropolymers was proven to reflect the relative expression yield of the subunits. When the cells of 2d culture were incubated with 14.3 mM Fe(2), the cellular iron concentration of Y1H10L and Y1L10H was 1.7 and 2.0 times, respectively, that of the control strain. It is assumed that increase in the iron uptake of the recombinant yeasts is closely related to ferritin expression and H subunit content.

• Food Science and Preservation
• /
• v.23 no.7
• /
• pp.1050-1057
• /
• 2016

This study was carried out to investigate the effectiveness of Leuconostoc mesenteroides isolated from octopus baechu kimchi as a potential starter for seafood kimchi. L. mesenteroides is lactic acid bacterium currently used as a starter for kimchi production. We selected the most effective L. mesenteroides strain from the 7 strains isolated from octopus baechu kimchi and, based on biochemical properties and 16S rRNA sequencing, identified the selected strain as L. mesenteroides SK-1. The SK-1 strain exhibited acid-tolerance, good survival capacity, and excellent dextran productivity. We investigated the effects the SK-1 of starter on seafood kimchi fermentation. Octopus baechu kimchi was fermented with L. mesenteroides SK-1 at $4^{\circ}C$ for 35 d. The decrease in pH and increase in acidity in octopus baechu kimchi fermented with the SK-1 starter occurred more quickly than that in the control kimchi indicating that. Octopus baechu kimchi with SK-1 starter has a relatively slow rate of increase in lactic acid production. As a result, octopus baechu kimchi prepared with L. mesenteroides SK-1 can be maintained at a suitable ripening degree over an extended period of time compared to that of the control kimchi, Moreover, the octopus baechu kimchi started with L. mesenteroides SK-1 has excellent sensory properties, including a refreshing taste, and a weak sour odor.

• Journal of Plant Biotechnology
• /
• v.46 no.1
• /
• pp.22-31
• /
• 2019

The objective of this study was to investigate the suitable parts for callus induction and optimal concentrations of growth regulators contained in the medium affecting shooting and rooting Echeveria laui and Echeveria elegans for in vitro mass production. To determine the suitable plant parts for callus induction, the leaves were divided into upper, medium and bottom parts and cultured on MS medium at different concentrations with $0{\sim}2mgL^{-1}\;NAA$ and $0{\sim}4 mgL^{-1}BA$. The upper and middle parts of leaves both showed 100% callus formation rate with $NAA\;1\;mgL^{-1}$ and $BA\;1\;mgL^{-1}$ treatment in E. laui. The middle parts of leaves showed 83.3% callus formation rate at $NAA\;2\;mgL^{-1}$ and BA 4 mgL-1 treatment in E. elegans. The shoot induction rate from callus was highest at $NAA\;0.1\;mgL^{-1}$ and $BA\;3\;mgL^{-1}$ treatment in E. laui and $NAA\;0.3\;mgL^{-1}$ in E. elegans. In addition, the number of shoots formation was 10.4 shoots high in $NAA\;1\;mgL^{-1}$ and $BA\;1\;mgL^{-1}$ treatment in E. laui and 12.0 shoots in most effective $NAA\;1\;mgL^{-1}$ and $BA\;0.1\;mgL^{-1}$ treatment in E. elegans. In the case of acclimatization of regenerated plant, growth characteristics did not show any significant difference (35 ~ 55%) shading with respect to the different ratio of substrate mixture, and it was determined that would be appropriate considered plant height and appearance preference of E. laui and E. elegans. It was established that the optimization of culture condition was responsible for the mass propagation in vitro cultures of E. laui and E. elegans.

• Korean Journal of Weed Science
• /
• v.16 no.3
• /
• pp.221-229
• /
• 1996

This study was carried out to determine the effects of growth regulators, carbon sources and silver nitrate on callus formation and plant regeneration of turfgrass. The results were summarized as fallows : Callus from Korean lawngrass (Zoysia japonica Steud.) and pencross creeping bentgrass (Agrostis palustrir Huds.) induced better in MS medium than in N6 medium and by addition of 2,4-D than by that of NAA. Callus formation from Korean lawngrass and penncross creeping bentgrass was very effective at MS medium adding 1mg/L 2,4-D and at the medium adding 2mg/L 2,4-D, repectively. Growth of callus was good at MS medium containing 2mg/L 2,4-D+0.2mg/L NAA. Callus growth of Korean lawngrass and penncross creeping bentgrass was good when kinetin was added 0.2mg/L and 0.3mg/L, individually, to MS medium containg 2mg/L 2,4-D+0.2mg/L NAA. Regeneration rate from leaf and stock callus of Korean lawngrass was 44% at MS medium adding 2,4-D 2mg/L+NAA 0.2mg/L+kinetin 0.3mg/L and 32% at the medium containing 2,4-D 2mg/L+NAA 0.2mg/L+kinetin 0.3mg/L, each and that from leaf and stock callus of penncross creeping bentgrass was 80% and 67%, each, at the medium adding 2,4-D 2mg/l+NAA 0.2mg/L+kinetin 0.3mg/L. Regeneration rate of Korean lawngrass and penneross creeping bentgrass increased by 3 to 4% and by 10 to 16%, respectively, when added $AgNO_3$ 1~2mg/L to the above-mentioned regeneration medium.

• BMB Reports
• /
• v.41 no.5
• /
• pp.363-368
• /
• 2008

Two genes of temperate mycobacteriophage L5, namely, gp63 and gp64, were hypothesized to be toxic to M. smegmatis. An identical L5 gp64 ortholog (designated hlg1) was cloned from homoimmune mycobacteriophage L1 and characterized at length here. As expected, hlg1 affected the growth of M. smegmatis when overexpressed from a resident plasmid. HLG1 (the protein encoded by hlg1) in fact caused growth retardation of M. smegmatis and the region encompassing its 57-114 C-terminal amino acid residues was found indispensable for its growthretardation activity. Both nucleic acid and protein biosynthesis were severely impaired in M. smegmatis expressing HLG1. Interestingly, HLG1 also affected E. coli almost similarly. This putative delayed early lipoprotein did not participate in the lytic growth of L1.

• BMB Reports
• /
• v.54 no.1
• /
• pp.12-20
• /
• 2021

In the last decade, we have witnessed an unprecedented clinical success in cancer immunotherapies targeting the programmed cell-death ligand 1 (PD-L1) and programmed cell-death 1 (PD-1) pathway. Besides the fact that PD-L1 plays a key role in immune regulation in tumor microenvironment, recently a plethora of reports has suggested a new perspective of non-immunological functions of PD-L1 in the regulation of cancer intrinsic activities including mesenchymal transition, glucose and lipid metabolism, stemness, and autophagy. Here we review the current understanding on the regulation of expression and intrinsic protumoral activity of cancer-intrinsic PD-L1.

• Journal of Korean Medicine for Obesity Research
• /
• v.23 no.2
• /
• pp.69-77
• /
• 2023

Objectives: Atriplex gmelinii C. A. Meyer is a halophyte belonging to the Chenopodiaceae family, and its young leaves and stems are used as fodder for livestock. The aim of the present study was to investigate the effects of A. gmelinii extract and its solvent fractions on lipid accumulation during adipogenesis of 3T3-L1 preadipocytes. Methods: The samples of A. gmelinii were separately extracted using methylene chloride and methanol. Subsequently, they were combined to formulate the initial extract, which was then partitioned based on polarity to prepare solvent fractions. Oil Red O staining was employed to measure lipid accumulation during the differentiation of 3T3-L1 preadipocytes. To verify cytotoxicity in 3T3-L1 cells, MTT assays were conducted. The expression levels of transcription factors in 3T3-L1 preadipocytes were measured through Western blotting analysis. Results: At 50 ㎍/mL, treatment of A. gmelinii extract and its solvent fractions during the differentiation of 3T3-L1 preadipocytes significantly diminished lipid accumulation with no noteworthy cytotoxicity on cell viability. Additionally, when investigating the biochemical pathways that underlie the prevention of lipid accumulation using solvent fractions, it was found that the n-BuOH and n-hexane fractions significantly decreased the expression of key transcription factors involved in the generation of fat, such as peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), and sterol regulatory element-binding protein-1c (SREBP1c). Conclusions: These findings indicate that A. gmelinii can effectively reduce the accumulation of fat in 3T3-L1 adipocytes, making it a potentially valuable material for mitigating and preventing obesity.