• Food Science and Preservation
• /
• v.13 no.5
• /
• pp.629-633
• /
• 2006

Pinus rigida Miller leaf extract (PRLE) showed antimicrobial activity remarkably against food pathogenic and spoilage bacteria at concentrations of $100{\sim}250{\mu}g/mL$. Alcohol-soluble PRLE had higher antimicrobial activity against Staphylococcus aureus and E-coli than any other-soluble PRLE such as butanol, ethyl acetate, ether and water. As PRLE concentration increased alcohol-soluble PRLE increased the remarkable inhibitory zone of microbial growth on the microbial media. PRLE showed good stability against temperature and pH in the range of $40{\sim}150^{\circ}C$ and $4{\sim}11$, respectively. This may indicate that PRLE can be a potential anti-microbial agent for industrial application. In addition, SEM of Listeria monocytogenes suggested that it antimicrobial component would perturb the functions of microbial cell membranes synergistically. In the feeding experiment the formaldehyde content in the serum of formalin-fed and PRLE-treated me decreased remarkably due to the lysis of formaldehyde and the rate of hemoglobin biosynthesis was recovered to the orignal state within a short breeding time.

• Journal of Life Science
• /
• v.33 no.8
• /
• pp.680-691
• /
• 2023

Peak oil, climate change, and microplastics caused by the production and usage of petroleum-based plastics have threatened the sustainability of our daily life, and this has emerged as a recent global issue. To solve this global issue, the production and usage of biodegradable eco-friendly bioplastics such as polyhydroxyalkanoates (PHAs) has been suggested as an alternative. Therefore, in this review, the present status of global PHA manufacturers, the advantages of the production of PHAs using marine-origin microorganisms (with their productivity potential) and further required research and development strategies for cost-competitive production of PHAs using marine-based microorganisms were investigated. In this review, PHAs produced from marine microorganisms were found to have similar physical properties to petroleum-based plastics but with several advantages that can reduce the costs of PHA production. Those advantages include, seawater used in the medium preparation step, and osmotic-based cell lysis technology used in the separation and purification steps. However, the PHA productivities from marine microorganisms showed somewhat lower efficiencies than those from the commercial strains isolated from terrestrial environments. In order to solve the problem, further research strategies using synthetic microbiology-based technology, the development of long-term continuous culture technology, and solutions to improve PHA efficiency are required to meet future market demands for alternative bioplastics.

• Journal of Life Science
• /
• v.28 no.11
• /
• pp.1354-1360
• /
• 2018

The aim of this study was to develop a simple, environmentally friendly synthesis of silver nanoparticles (SNPs) without the use of chemical reducing agents by exploiting the extracellular synthesis of SNPs in a culture supernatant of Bacillus thuringiensis CH3. Addition of 5 mM $AgNO_3$ to the culture supernatant at a ratio of 1:1 caused a change in the maximum absorbance at 418 nm corresponding to the surface plasmon resonance of the SNPs. Synthesis of SNPs occurred within 8 hr and reached a maximum at 40-48 hr. The structural characteristics of the synthesized SNPs were investigated by various instrumental analysis. FESEM observations showed the formation of well-dispersed spherical SNPs, and the presence of silver was confirmed by EDS analysis. The X-ray diffraction spectrum indicated that the SNPs had a face-centered cubic crystal lattice. The average SNP size, calculated using DLS, was about 51.3 nm and ranged from 19 to 110 nm. The synthesized SNPs exhibited a broad spectrum of antimicrobial activity against a variety of pathogenic Gram-positive and Gram-negative bacteria and yeasts. The highest antimicrobial activity was observed against C. albicans, a human pathogenic yeast. The FESEM observations determined that the antimicrobial activity of the SNPs was due to destruction of the cell surface, cytoplasmic leakage, and finally cell lysis. This study suggests that B. thuringiensis CH3 is a potential candidate for efficient synthesis of SNPs, and that these SNPs have potential uses in a variety of pharmaceutical applications.

• Korean Journal of Food Science and Technology
• /
• v.21 no.1
• /
• pp.154-163
• /
• 1989

This studies were designed to improve the productivity of L-lysine by protoplast fusion and immobilized system of fusants using strains of Brevibacterium flavum ATCC 21528, Brevibacterium lactofermentum ATCC 21086 and Corynebacterium glutamicum 820. Mutants were isolated with concentration method of $300{\mu}g/ml$ penicillin-G after treatment of $250{\mu}g/ml$ N-methyl-N-nitro-N-nitrosoguanidine. B. flavum $37-2(Hos^-,\;Kan^r,\;AEC^r)$, B. lactofermentum $6-2(Ile^-,\;Val^-,\;Str^r,\;AEC^r)$ and C. glutamicum 57-5$(Met^-,\;Thr^-,\;Rif^r,\;AEC^r)$ were isolated from mutants. Protoplasts were induced by being incubated with $500{\mu}g/ml$ lysozyme of lysis solution for 6 hr and the ratio of protoplast formation and regeneration were ranging from 97-99% and 33-37%, respectively. Fusion frequencies of fusants of BBFL 21, BCFG 37 and BCLG 59 were shown in the range from $1.25{\times}10^{-6}\;to\;5.83{\times}10^{-7}$ under the optimum conditions. The fusant BBFL 21 showed the highest productivity of $411.1\;ng/ml{\cdot}hr$ L-lysine in the lysine productivity broth at $30^{\circ}C$ for 72hr. In the immobilization systems, fusant BBFL 21 was employed in various polymer matrices such as sodium alginate, polyacrylamide, agar and ${\alpha}-carrageena$. The immobilization of sodium alginate showed the highest productivity of $413\;ng/ml{\cdot}hr$ L-lysine in the batch system. Continuous fermentation of immobilization system by using tube fermentor was produced the highest productivity $416.7\;ng/ml{\cdot}hr $ L-lysine under optimum condition.

• Proceedings of the Ginseng society Conference
• /
• 2007.05a
• /
• pp.23-24
• /
• 2007

Purpose: 인삼이 항당뇨 활성을 가진다는 연구가 많은 연구자들에 의해 진행되었고, 이는 인삼의 구성 성분 중 ginsenoside에 기인한다는 보고가 있다. 본 연구는 ginsenoside의 항당뇨 작용기전을 in vitro에서 알아보고자 3T3-L1 지방세포에서 glucose uptake와 췌장 베타세포인 HIT-T15 세포에서 insulin 분비 효과를 확인하였다. 이를 위하여 인삼을 식초로 처리한 긴삼의 70% MeOH 분획으로부터 protopanaxadiol 계인 ginsenoside $Rb_2$, $Rg_3$ 그리고 protopanaxtriol 계인 $Rg_2$를 분리하여 본 실험에 사용하였다. Method: Ginsenoside $Rb_2$, $Rg_2$, $Rg_3$가 지방 세포에서 glucose uptake에 미치는 효과를 확인하기 위하여 3T3-L1 세포를 DMEM (Dulbecco's Modified Eagle's Medium) 배지에서 분화 유도시켰으며 3T3-L1 preadipocyte가 80% 정도 자라면 분화 유도 배지 (5% fetal bovine serum (FBS), 0.5 mM isobutylmethylxanthine (IBMX), 1 mM dexamethasone 그리고 $10{\mu}g/ml$ insulin가 포함된 DMEM)로 4일, $10{\mu}g/ml$ insulin가 포함된 DMEM으로 2일, FBS만 포함된 DMEM으로 2일 배양하여 총 8일 동안 분화를 유도하였다. 분화 유도된 3T3-L1 adipocytes 에 각각 $Rb_2$, $Rg_2$, $Rg_3$를 $20{\mu}M$로 처리하여 16시간 배양하여 low glucose DMEM에서 3시간 배양한 후에 $37^{\circ}C$에서 insulin 10 ng/ml 과 각각 $Rb_2$, $Rg_2$, $Rg_3$가 포함된 Krebs Ringer Hepes buffer(KRP buffer)에서 20분간 배양하였다. 2-deoxy-D-[$^3H$]-glucose를 넣고 10분 후에 차가운 PBS로 반응을 종결시켜 lysis buffer로 cell을 모은 후 scintillation counter를 이용하여 glucose를 측정하였다. Insulin 분비 효과는 HIT-T15 세포와 일차 배양한 흰쥐 소도세포(islets)를 사용하여 확인하였다. HIT-T15 세포는 24 well plate에 well 당 $2{\times}10^5$ 개씩 분주하여 24시간 동안 배양한 후 시료를 처리하였으며 소도 세포는 Sprague-Dawley rat의 췌장에 collagenase가 포함된 Hanks' Balanced Salt Solution(HBSS)을 주입하여 분리하고 islets을 얻었다. 분리한 소도세포를 $1{\sim}2$일 동안 배양하여 $Rb_2$, $Rg_2$, $Rg_3$가 각각 $20{\mu}M$의 농도로 첨가된 insulin 측정용 buffer인 Krebs-Ringer buffer (KRB+0.3% BSA, KRBB)에 $37^{\circ}C$에서 1시간 incubation 시킨 후 배양액으로 분비된 인슐린의 양을 측정하였다. 한편 ginsenoside의 인슐린 분비 촉진 기전을 알아보기 위한 실험에서는 ATP-sensitive $K^+$ channel opener인 diazoxide (0.5 mM)가 ginsenoside에 의해 촉진된 인슐린 분비를 억제하는지 살펴보았다. Result: glucose uptake assay 에서는 $Rg_2$가 가장 크게 glucose uptake를 증가시켰고 $Rb_2$, $Rg_3$는 그 활성이 크지 않았다. 한편 Insulin 분비 효과는 diol계인 $Rg_3$에서 용량 의존적으로 인슐린의 분비를 촉진시켰으며 $20{\mu}M$ 농도에서 대조군과 비교해 1.5배 이상의 분비 촉진 효과를 보였고 triol계인 $Rg_2$ 에서는 이러한 효과가 나타나지 않았다. $Rg_3$의 인슐린 분비 촉진 기전을 0.5 mM 의 diazoxide를 이용하여 확인한 결과 $Rg_3$에 의해 촉진된 인슐린 분비를 감소시켰다. 이로 미루어보아 $Rg_3$의 인슐린 분비 촉진 기전은 ATP-sensitive $K^+$ 채널의 봉쇄에 의한 것임을 확인할 수 있었다.

• Tuberculosis and Respiratory Diseases
• /
• v.51 no.4
• /
• pp.303-314
• /
• 2001

Background : Matrix metalioproteinase(MMP)-2 and MMP-9 have been known to play an important role in cell migration and the tissue remodeling process by type IV collagen lysis, a major component of the basement membrane. Intra-alveolar fibrosis, secondary to an injury to the basement membrane of the alveolar epithelial lining, is a major process in the pathogenesis of idiopathic pulmonary fibrosis(IPF). Therefore, MMP-2 and MMP-9 was hypothesized to play an important role in IPF pathogenesis. As a result, their level may reflect the activity or prognosis. Method : Forty one progressive IPF patients(age $59.82{\pm}1.73$ years, M:F=23:18), 16 patients with stable IPF for more than one year without therapy(age : $63.6{\pm}2.8$ years, M:F=13:3), and 7 normal controls were enrolled in this study. The MMP-2 and MMP-9 levels in the BAL fluid and alveolar macrophage conditioned media(AM-CM) were measured by zymography and the TIMP-1 level was measured by ELISA. Results : 1) The MMP-2 level in BALF was highest in the progressive IPF group ($1.36{\pm}0.28$) followed by the stable group ($0.46{\pm}0.13$) and the controls ($0.08{\pm}0.09$), which was statistically significant. The MMP-9 level of the IPF ($0.31{\pm}0.058$) and the stable group ($0.22{\pm}0.078$) were higher than that of the control group ($0.002{\pm}0.004$). In the AM-CM, only MMP-9 was detected, which was significantly higher in IPF group ($0.80{\pm}0.1O$) than in the control group($0.23{\pm}0.081$). The TIMP-1 level was also higher in both the IPF ($36.34{\pm}8.62\;{\mu}g/ml$) and stable group ($20.83{\pm}8.53\;{\mu}g/ml$) compared to the control group ($2.80{\pm}1.05\;{\mu}g/ml$) (p<0.05). 3) There was a correlation between the MMP-2 level in the BALF with the total cell number(r=0.298) and neutrophils(r=0.357) (p<0.05), and the MMP-9 level with the number of neutrophils (r=0.407) and lymphocytes (r=0.574)(p<0.05). The TIMP-1 level correlated with the total number of cell (r=0.338, p<0.05) and neutrophils(r=0.449, p=0.059). Conclusion : Both MMP and TIMP appear to play an important role in IPF pathogenesis, and their level may reflect the disease activity.