• Journal of Food Hygiene and Safety
• /
• v.11 no.4
• /
• pp.227-234
• /
• 1996

This study was designed to characterize endotoxin-induced prostaglandin production in primary cultured rat vascular smooth muscle cells (VSMC). The time course for prostaglandin synthesis in lipopolysaccharide (LPS)-stimulated VSMC showed that the maximum production was reached in 12 hours. LPS induced prostaglandin H2 synthase (PGHS) activity in VSMC and the time course profile in the changes of PGHS activity paralleled that of total prostaglandin production. Differential treatment showed that 4 hours' exposure to LPS was enough for the maximum effect on the prostaglandin production and this effect was completely inhibited by the co-treatment of actinomycin D, a transcription inhibitor. These results suggest that LPS effect might be determined within 4 hours. Actinomycin D increased PGHS activity without affecting prostaglandin production if added 4 hours after LPS treatment. On the other hand, cyclogeximide, a translation inhibitor, augmented LPS-induced prostaglandin production if treated during first four hours, but it inhibited LPS-induced PGHS activity regardless of treatment schedule. These results suggest the existence of multiple regulating mechanisms in the LPS-induced prostaglandin synthesis.

• Journal of Korean Institute of Industrial Engineers
• /
• v.23 no.2
• /
• pp.403-420
• /
• 1997

In this paper, we examine the effect of production uncertainty to production control policies. First, we examine two famous production control policies, namely, MRP and JIT from the view point of shop floor control perspective, and analyze the differences between them due to demand fluctuations and activity time variations. Second, we conduct simulation studies on MRP and JIT to draw out the effects of demand fluctuations and activity time variations. Demand fluctuations are further classified into demand lumpiness and demand irregularity. And, activity time variations are further classified into stationary time variations and non-stationary time variations. Experimental results show that, in terms of demand fluctuations, MRP is affected by demand lumpiness, but JIT by demand irregularity. And we also see that both MRP and JIT are influenced by stationary time variation with respect to activity time variations.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.416-421
• /
• 2001

The domestic reinforcement concrete works have mainly worked the process of re-bar fabrication/assembly on site and re-bar works affected by structural safety, durability, and schedule with form work. Accordingly, This study analyzes the process of re-bar fabrication/assembly on site to apply lean production principles to construction Value Stream Analysis(VSA) is analyzed into value-adding activity and non-value-adding activity on construction process through value analysis and Value Stream Mapping(VSM). In the results, non-value-adding activity generates waste such as the activity steps, labors, equipments, materials, time, and so on. Additionally, push-driven production is investigated making low productivity from the overproduction and so on. To resolve the problems in the process, The purpose of this paper eliminates waste factor through maximizing the value-adding activity generating value added and minimizing non-value adding activity. Particularly, it makes flow production and pull-driven production through minimizing work-in-process(WIP ).

• YAKHAK HOEJI
• /
• v.47 no.1
• /
• pp.31-36
• /
• 2003

To investigate the effect of protein kinase on melanin production via cAMP-dependent pathway, we measured the melanin amount and tyrosinase activity in B16 melanoma cells stimulated by alpha-melanocyte stimulating hormone (MSH), forskolin and 8-Br-cAMP. MSH, forskolin and 8-Br-cAMP significantly increased both melanin production and tyrosinase activity in B16 cells. Melanin production and tyrosinase activity by MSH are significantly inhibited by cyclic AMP-dependent protein kinase inhibitor (KT5720) and protein kinase C down-regulation treated with PMA. Bisindolmaleimide (1$\mu$M), protein kinase C inhibitor, significantly inhibited melanin production and tyrosinase activity stimulated by MSH, forskolin and 8-Br-cAMP with the following order of potency: MSH＞forskolin＞8-Br-cAMP. Tyrosine kinase inhibitor, genistein and DHC, significantly inhibited both, but the inhibitory effect was more potent in 8-Br-cAMP-stimulated B16 cells than MSH-stimulated cells. NFkB inhibitor (parthenolide) significantly inhibited melanin production and tyrosinase activity. Neither melanin production nor tyrosinase activity induced by MSH, forskolin and 8-Br-cAMP were affected by KN-62 (calmodulin-dependent protein kinase II inhibitor), PD098059 (mitogen-activated protein kinase inhibitor, MAPKK) and worthmannin (phosphatidylinositol 3-kinase inhibitor). These results suggest that both protein kinase C and tyrosine kinase are involved in melanin production by cyclic AMP-dependent pathway and NFkB pathway may play an important role in cyclic AMP-dependent melanin production in B16 melanoma cells.

• The Korea Journal of Herbology
• /
• v.36 no.4
• /
• pp.23-30
• /
• 2021

Objectives : The purpose of this study was to investigate the antioxidant activities and nitric oxide (NO) production in RAW 264.7 macrophages in extract of Alisma orientale Juzep (EAOJ) and fermented extract (FAOJ) by Paenibacillus kribbensis AM49 (P. kribbensis AM49). Methods : The Alisma orientale Juzep was fermented with P. kribbensis AM49 at 37℃ for 72 hours. We measured total polyphenol and total flavonoid, DPPH radical scavenging activity, FRAP activity and reducing power by spectrometric assay in EAOJ and FAOJ at concentrations at 0.5, 1, 5, 10 mg/㎖. Positive control was used ascorbic acid. Furthermore, we examined effect of EAOJ and FAOJ on the cell viability and NO production in RAW 264.7 macrophages. Results : The total polyphenol and total flavonoids content of FAOJ were increased 9.16 mg/g, 2.59 mg/g to 12.58 mg/g, 3.45 mg/g. DPPH radical scavenging activity, FRAP activity and reducing power were dose dependently increased according to the treatment concentration (0.5, 1, 5, 10 mg/㎖) of EAOJ and FAOJ. In particular, DPPH radical scavenging activity, FRAP activity of FAOJ was significantly increased at 5, 10 mg/㎖. Reducing power of FAOJ at 10 mg/㎖ was similar to ascorbic acid at 0.1 mg/㎖. In addition, the cell viability and NO production in RAW 264.7 macrophages were significantly increased at the concentrations of 250, 500, 1000 ㎍/㎖. Conclusions : These results suggest that FAOJ by P. kribbensis AM49 has effects to antioxidant activity. In addition, the cell viability and NO production in RAW 264.7 macrophages were significantly increased.

• YAKHAK HOEJI
• /
• v.47 no.6
• /
• pp.398-403
• /
• 2003

To investigate the relationship between structure and biological activity of phenylpropanoids, we measured effects of phenylpropanoids on anti-oxidant and whitening activity, In DPPH radical scavenging activity, caffeic acid analogues showed the significant anti-oxidant activity. Although phenylpropanoids did not inhibit purified-tyrosinase activity, they significantly inhibited tyrosinase activity and melanin production in MSH-stimulated B16 melanoma cells. However, phenylpropanoids did not affect tyrosinase expression in MSH-stimulated B16 melanoma cells, which suggest that inhibition of MSH-induced melanin production was due to tyrosinase inhibition mediated via other signal pathways but not expression of tyrosinase. Phenylpropanoids also significantly inhibited both hyaluronidase and elastase activity, suggesting that phenylpropanoids may be used as whitening, hydration and anti-wrinkling agents. Hydroxyl residue of aromatic ring in phenylpropanoids plays an important role in anti-oxidant and whitening activity.

• Journal of Animal Science and Technology
• /
• v.63 no.5
• /
• pp.1159-1168
• /
• 2021

Ovotransferrin (OTF), an egg protein known as transferrin family protein, possess strong antimicrobial and antioxidant activity. This is because OTF has two iron binding sites, so it has a strong metal chelating ability. The present study aimed to evaluate the improved immune-enhancing activities of OTF hydrolysates produced using bromelain, pancreatin, and papain. The effects of OTF hydrolysates on the production and secretion of pro-inflammatory mediators in RAW 264.7 macrophages were confirmed. The production of nitric oxide (NO) was evaluated using Griess reagent and the expression of inducible nitric oxide synthase (iNOS) were evaluated using quantitative real-time polymerase chain reaction (PCR). And the production of pro-inflammatory cytokines (tumor necrosis factor [TNF]-α and interleukin [IL]-6) and the phagocytic activity of macrophages were evaluated using an ELISA assay and neutral red uptake assay, respectively. All OTF hydrolysates enhanced NO production by increasing iNOS mRNA expression. Treating RAW 264.7 macrophages with OTF hydrolysates increased the production of pro-inflammatory cytokines and the phagocytic activity. The production of NO and pro-inflammatory cytokines induced by OTF hydrolysates was inhibited by the addition of specific mitogen-activated protein kinase (MAPK) inhibitors. In conclusion, results indicated that all OTF hydrolysates activated RAW 264.7 macrophages by activating MAPK signaling pathway.

• Journal of Microbiology and Biotechnology
• /
• v.8 no.4
• /
• pp.341-346
• /
• 1998

Optimization for the production of Pest an was followed by the Plackett-Burman Design, using modified Czapek-dox medium as the starting point. At the flask level, $K_2HPO_4$, $MgSO_4{\cdot}7H_2O$, and aeration variables positively affected the Pestan production, DCW (dry cell weight), apparent viscosity, and flocculating activity response. KCI and $FeSO_4{\cdot}7H_2O$ negatively affected the Pestan production, DCW, apparent viscosity, and flocculating activity response. Aeration variable was shown to have a positive effect on only the flocculating activity response among Pestan production, DCW, and apparent viscosity responses. In comparison of the positive and negative variables media conditions, Pestan production and flocculating activity differed by about 9 and 125 times, respectively. In particular, at the jar fermentor level, the aeration variable was the most important factor of the all responses (pestan production, DCW, apparent viscosity, flocculating activity, and anionic charge density). The flocculating activity and apparent viscosity of Pestan were closely related to the molecular chain length and charge density.

• Environmental and Resource Economics Review
• /
• v.23 no.2
• /
• pp.349-364
• /
• 2014

This study analyzed Granger causality between power consumption and production activity in manufacturing sector, by using error correction model. It found that there exists the connection between power consumption and production activity in manufacturing sector. By reflecting the industrial characteristics, it found not only the bilateral causality (power consumption ${\leftrightarrow}$ production activity) in power non-intensive industry, high value-added industry and low value-added industry, but also one-way causality (power consumption ${\rightarrow}$ production activity) in power-intensive industry. These results imply that power demand management policy focusing on efficiency improvement is necessary primarily to minimize negative impacts on production activity, and also stable power supply system is required to meet the increase of power demand.

• YAKHAK HOEJI
• /
• v.47 no.6
• /
• pp.404-409
• /
• 2003

To investigate the effect of chitosan oligosaccharide on melanin synthesis, we measured tyrosinase activity and melanin production in B16 melanoma cells. Chitosan oligosacchaide itself did not have any anti-oxidant activity in DPPH radical scavenging, and did not affect the proliferation of B16 melanoma cells. Chitosan oligosaccharide dose-dependently increased melanin production in the absence or presence of MSH. However, chitosan oligosaccharide did not have any influence on the tyrosinase activity and tyrosinase expression in B16 melanoma cells. These results suggest that chitosan oligosaccharide-induced melanin production may be independent on tyrosinase activity in B16 melanoma cells. From the above results. chitosan oligosaccharide dose-dependently appears to increase melanin production in B16 melanoma cells, suggesting that chitosan oligosaccharide may be used as a tanning agent.