• Journal of Microbiology and Biotechnology
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• 제11권5호
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• pp.739-748
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• 2001

A self-organizing fuzzy logic controller using a genetic algorithm is described, which controlled the glucose concentration for the enhancement of flavonoid production in a fed-batch cultivation of Scutellaria baicalensis G. plant cells. The substrate feeding strategy in a fed-batch culture was to increase the flavonoid production by using the proposed kinetic model. For the two-stage culture, the substrate feeding strategy consisted of a first period with 28 g/I of glucose to promote cell growth, followed by a second period with 5 g/I of glucose to promote flavonoid production. A simple fuzzy logic controller and the self-organizing fuzzy logic controller using a genetic algorithm was constructed to control the glucose concentration in a fed-batch culture. The designed fuzzy logic controllers were applied to maintain the glucose concentration at given set-points of the two-stage culture in fed-batch cultivation. The experimental results showed that the self-organizing fuzzy logic controller improved the controller\`s performance, compared with that of the simple fuzzy logic controller. The specific production yield and productivity of flavonoids in the two-stage culture were higher than those in the batch culture.

• 대한의생명과학회지
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• 제15권4호
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• pp.281-286
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• 2009

We found previously that Undaria pinnatifida extract has an effect of lowering blood glucose levels in diabetic rats. Therefore, an effect of Undaria pinnatifida extract on the insulin secretion directly from the pancreas was examined in this study. Neonatal diabetes were induced by intraperitoneal injection of Streptozotocin (100 mg/kg body weight) at age of day 1. Rats were fed a rodent pellet diet until they were grown to adults (age of 7 weeks). Rats having a fasting serum glucose level over 250 mg/dL were used in this feeding study and they were divided into two diet groups as follows; a diet with Undaria pinnatifida extract (5%) and a diet without this extract (control group). Fasting (12 hr) blood glucose and serum insulin levels were measured before and after feeding a diet with Undaria pinnatifida extract for 4 weeks. At the last day of feeding, in vitro pancreas perfusion was performed. Pancreas was stimulated with a perfusate without glucose during a period of 0~10 minutes and with a perfusate containing 200 mg/dL glucose during a period of 11~40 minutes. Insulin amount was measured using a radioimmuno assay. In results, amount of the insulin secreted from the pancreas in the diabetic rats fed Undaria pinnatifida extract was significantly greater than that in the diabetic control group during the periods of the equilibration period (0~10 min) and the first phase (11~20 min) of the insulin secretion (P<0.05). It is concluded that Undaria pinnatifida extract increases insulin secretion from the pancreas in the neonatal diabetic rats. Therefore, the blood glucose lowering effect of the Undaria pinnatifida extract may be elucidated by mechanisms with promoted insulin secretion from the pancreas in diabetic rats.

• Journal of Nutrition and Health
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• 제35권6호
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• pp.643-649
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• 2002

This study was done to investigate effects of ${\gamma}$-irradiated pork feeding on the formation of glutathione S-transferase placental form positive (GST-P$^{+}$) foci, lipid peroxidation, cytochrome P450 system and microsomal glucose 6-phosphatase activity in diethylnitrosamine (DEN)-initiated rat hepatocarcinogenesis. Weaning Sprague-Dawley male rats were fed the diet containing ${\gamma}$-irradiated ground pork at the dose of 0, 3, 10, 30 kGy as a 20％ of protein source for 8 weeks. One week after feeding, rats were intraperitoneally injected twice with a dose of DEN (50 mg/kg BW). As a promote.,0.05％phenobarbital was fed in drinking water from one week after DEN treatment until the end of experiment. At the end of 8th week, rats were sacrificed and hepatic GST-P$^{+}$ foci, microsomal malondialdehyde (MDA) and conjugated diene contents were determined. In addition, cytochrome P450 content and the activities of NADPH cytochrome P450 reductase and glucose 6-phosphatase were also measured. There was no significant effect by gamma irradiation on microsomal MDA content, conjugated diene, cytochrome P450 content and activities of NADPH cytochrome P450 reductase and glucose 6-phosphatase. However with DEN treatment, microsomal MDA content showed a increasing tendency. Cytochrome P450 content was also significantly increased while microsomal glucose 6-phophatase activity was significantly decreased with DEN treatment. However the activity of NADPH cytochrome P450 reductase was not affected. An interesting finding in this study was that the number and area of hepatic GST-P$^{+}$ foci of rats fed gamma irradiated pork were tended to be decreased by high dose of irradiation, but were not significantly different. These results might imply that the consumption of low dose of gamma irradiated pork does not affect the formation of hepatic GST-P$^{+}$ foci and lipid peroxide and membrane stability.ability.

• 한국식품영양과학회지
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• 제28권3호
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• pp.638-645
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• 1999

This study was done to investigate effects of ${\gamma}$ irradiated beef feeding on the formation of gluta thione S transferase placental form positive(GST P+) foci, lipid peroxidation, cytochrome P450 system and microsomal glucose 6 phosphate activity in diethylnitrosamine(DEN) initiated rat hepatocarci nogenesis. Weaning Sprague Dawley male rats were fed the diet containing ${\gamma}$ irradiatied ground beef at the dose of 0, 3, 5kGy as a 20% of protein source for 8 weeks. One week after feeding, rats were intraperitoneally injected twice with a dose of DEN(50mg/kg BW). As a promoter, 0.05% phenobarbital was fed in drinking water from one week after DEN treatment until the end of experiment. At the end of 8th week, rats were sacrificed and hepatic GST P+ foci, microsomal malondialdehyde(MDA) and conjugated diene contents were determined. In addition, cytochrome P450 content and the activities of NADPH cytochrome P450 reductase and glucose 6 phosphatase were also measured. There was no significant effect by gamma irradiation on microsomal MDA content, conjugated diene, cytochrome P450 content and activities of NADPH cytochrome P450 reductase and glucose 6 phosphatase. However with DEN treatment, microsomal MDA content and conjugated diene contents were significantly changed. Cytochrome P450 content was also significantly increased while microsomal glucose 6 phophatase activity was significantly decreased with DEN treatment. However activity of NADPH cytochrome P450 reductase was not affected. An interesting finding in this study was that the number and area of hepatic GST P+ foci of the rats fed gamma irradiated beef were significantly(p<0.05) lower than those of the control. Such a lowering effect on GST P+ foci formation was highest at the dose of 3kGy than others. Overall results suggest that the consumption of low dose of gamma irradiated beef does not affect the formation of lipid peroxide, cytochrome P450 system and membrane stability.

• 한국응용곤충학회지
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• 제48권4호
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• pp.467-477
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• 2009

꽃매미의 식물에 대한 선호도을 조사한 결과, 가죽나무와 포도나무를 가장 선호하였으며, 사과나무, 배나무, 무궁화나무, 소나무와 복숭아 나무는 선호하지 않는 것으로 나타났다. 7종 식물에 대하여 꽃매미 약충과 성충은 가죽나무와 포도나무에서 가장 오래 생존하였고, 다른 식물에서는 생존기간이 짧았다. 과수열매에서는 거의 생존하지 못하였다. 꽃매미의 섭식행동 분석결과, 약충과 성충 모두 가죽나무와 포도나무에서 섭식하지 않는 시간(non-probing time)은 가장 짧았고, 체관부 섭식시간(phloem-feeding time)은 가장 길었다. 이를 제외한 나머지 식물과 열매에서는 체관부 섭식시간이 0분으로 섭식을 하지 못하였다. 5종 식물을 당 분석한 결과, 가죽나무는 sucrose 함량이 가장 높았고 fructose > glucose순으로, 포도나무에는 glucose > fructose > maltose > sucrose > rhamnose순이고, 사과나무는 glucose > fructose, 배나무는 glucose > unknown > fructose, 무궁화나무는 sucrose > glucose 순으로 당 성분이 존재하였다. Parafilm membrane 검정법으로 생존기간을 조사한 결과, 약충과 성충 모두 sucrose 5%용액에서 가장 생존기간이 길었으며, fructose 5%용액이 그 다음이었다. 이를 제외한 나머지 성분에서는 짧은 수명을 나타내었다. 분석된 당 성분의 조합에 의한 검정에서도 약충과 성충 모두 가죽나무와 포도나무의 당 성분조합에서 다른 당 성분조합과 비교하여 긴 수명을 보였다. 당 성분이 꽃매미가 기주를 선택하고 섭식하는데 영향을 미치는 것으로 생각된다.

• Journal of Nutrition and Health
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• 제28권5호
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• pp.375-386
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• 1995

This study was designed to investigate the changes in energy substrates, glucose and non-esterified fatty acid(NEFA), and fatty acid compositions in serum, following physiolgical stress in rats fed diets containing various fatty acids. Forty two Sprague-Dawley strain male rats, weighing 108$\pm$2.1g, were fed 3 different experimental diets for 4 weeks. The diets were composed of 105 fat(w/w) of either corn oil(CO;18:2 n6:57%), plant perilla oil(PO;18:3 n3:59%), or tuna fish oil(FO;20:5 n3:17%%, 22:6 n3:19%). After 4 weeks of feeding, each group wa subdiveided into (a) control, (b) 2 min swim in ice-cold water. Animals wer decapitated 20min after commencing the swim; trunk blood, brain, liver and epididymal fat pad were obtained. The levels of serum corticosterone, glucose, NEFA, triglyceride, fatty acid compositions, brain serotonin and 5-hydroxyindoleacetic acid were determined. Basal levels of corticosterone na NEFA of serum were significantly lower in fish oil fed animals than those of any other oil fed animals. Compared to either perilla oil-fed or corn oil-fed rats, cold swim stress in fish oil fed rats produced significantly smaller NEFA and larger corticosterone responses. However, there was no significant difference in basal levels of serum glucose. Stress increased serum glucose levels slightly, and the amount of increment was larger in fish oil rats than those of any other oil fed rats than those of any other oil fed rats, although all the values were normal level. Dietary fats and stress did not affect serotonin metabolism. In additions, the composition of fatty acids in serum was significantly affected by the dietary compostion of fatty acids and stress. Stress induced decreases in monounsaturated fatty acid and non-polyunsaturated fatty acid concentration in either perilla oil fed or fish group, but did not in corn oil fed group. Stress resulted in changes in fatty acid metabolism similar to that associated with essential fatty acid(EFA) dificiency, when feeding animals n-3 fatty acids in diet. In conclusion, feeding fish oil was more effective to decrease NEFA in serum than feeding perilla oil or corn oil and improved lipid metabolism, when the rats were maintained in normal or exposed to stressful environment. However, the fact that feeding diet containing n-3 fatty acids decreased EFA status under stress suggests that the requirement of n-6 PUFA should be increased in these groups.

• Journal of Microbiology and Biotechnology
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• 제24권1호
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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.

• Advances in Traditional Medicine
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• 제1권2호
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• pp.14-20
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• 2000

This study was designed to investigate the effect of dietary Platycodon grandiflorum on plasma glucose and lipid metabolism in $KK-A^y$ mice and STZ-induced diabetic rats. Both plasma triglyceride and plasma cholesterol levels in STZ-induced diabetic rats were significantly decreased by dietary Platycodon grandiflorum feeding for 4 weeks compared to those of control rats, but there were no marked differences in $KK-A^y$ mice. However, for plasma glucose values, Platycodon grandiflorum feeding resulted in a significant decrease in both STZ-induced diabetic rats and $KK-A^y$ mice. Also, dietary Platycodon grandiflorum slightly decreased the postprandial glucose level at 30 and 60 mins during oral glucose tolerance test in $KK-A^y$ mice. Although there was no statistical significance, the fasting plasma insulin levels of Platycodon grandiflorum dieted $KK-A^y$ mice tended to decrease when compared to that of control mice. Therefore, the present results suggested that dietary Platycodon grandiflorum may have a beneficial effect on preventing hypercholesterolemia and hyperlipidemia.

• Journal of Ginseng Research
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• 제4권1호
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• pp.40-48
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• 1980

This study was to investigate the feeding effects of diet supplemented with 2% ginseng powder on the growth rate and the blood glucose of rats. The Albino rats (48 heads), weighing 98 to 105g, were divided into two different diet groups, which were subdivided into six subgroups for insulin and epinephrine treatment. They were 1) Co group as control, 2) CG group as control group contained 2% ginseng powder, 3) Io group fed on the diet of Co group and treated with insulin, 4) IG group fed on the diet of CG group and treated with insulin, 5) Eo group fed on the diet of Co group and treated with epinephrine, and 6) EG group fed on the diet of CG group and treated with epinephrine. Each animal group was maintained with the corresponding diet for 27 days, and then they were sacrificed. The growth rate of rats and the diet consumption and efficiency ratio of food and protein were determined during the feeding period. After sacrificing of the animals, the weight of some organs and the blood glucose were analyzed. The results obtained are summarized as follows; 1. The gained body weights of the dietary group supplemented with 2% ginseng powder(CG) were less increased in comparison to the corresponding control group(Co). Those of IG were significantly higher than those of to (p<0.01). Those of EG were significantly lower than those of Eo group (p<0.01). 2. It was found that the variations of the efficiency ratio of food and protein showed the similarity in those of the growth of each group. 3. The final weights of liver kidney spleen. and heart were not significantly different between Co and CG. The weights of the liver, kidney, and heart of IG were significantly greater than those of Co (p<0.05). The weights of the liver and heart of EG were significantly lower than those of Eo(p<0.01) 4. The blood glucose of CG was a little higher than that of Co, but not significant. Also it was found that was little difference between IG and Io. It showed that the blood glucose of EG was significantly lower than that of Eo(p<0.0 1).

• Journal of Animal Science and Technology
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• 제59권6호
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• pp.14.1-14.9
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• 2017

Background: Garlic and its constituents are reported to have been effective in reducing methane emission and also influence glucose metabolism in body; however, studies in ruminants using garlic leaves are scarce. Garlic leaves contain similar compounds as garlic bulbs, but are discarded in field after garlic bulb harvest. We speculate that feeding garlic leaves might show similar effect as garlic constituents in sheep and could be potential animal feed supplement. Thus, we examined the effect of freeze dried garlic leaves (FDGL) on rumen fermentation, methane emission, plasma glucose kinetics and nitrogen utilization in sheep. Methods: Six sheep were fed Control diet (mixed hay and concentrate (60:40)) or FDGL diet (Control diet supplemented with FDGL at 2.5 g/kg $BW^{0.75}$ of sheep) using a crossover design. Methane gas emission was measured using open-circuit respiratory chamber. Plasma glucose turnover rate was measured using isotope dilution technique of [$U-^{13}C$]glucose. Rumen fluid, feces and urine were collected to measure rumen fermentation characteristics and nitrogen utilization. Result: No significant difference in rumen fermentation parameters was noticed except for rumen ammonia tended to be higher (0.05 < P < 0.1) in FDGL diet. Methane emission per kg dry matter ingested and methane emission per kg dry matter digested were lower (P < 0.05) in FDGL diet. Plasma glucose concentration was similar between diets and plasma glucose turnover rate tended to be higher in FDGL diet (0.05 < P < 0.1). Nitrogen retention was higher (P < 0.05) and microbial nitrogen supply tended to be higher (0.05 < P < 0.1) in FDGL diet. Conclusion: FDGL diet did not impair rumen fermentation, improved nitrogen retention; while absence of significant results in reduction of methane emission, glucose turnover rate and microbial nitrogen supply, further studies at higher dose would be necessary to conclude the merit of FDGL as supplement in ruminant feedstuff.