• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.587-595
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• 2019

Pharmacological research on (CHA), a marine-derived quinazolinone alkaloid with significant cytotoxic activity, is restricted by low yields and is a problem that needs to be settled urgently. In this work, the selection of additional nitrogen sources and the optimization of additional concentrations and longer fermentation times using ammonium acetate, were investigated. CHA production was optimized to 62.1 mg/l with the addition of 50 mM ammonium acetate at 120 h of the fermentation in the shaker flask. This feeding strategy significantly increased 3-deoxy-arabino-heptulosonate-7-phosphate synthase activity and transcript levels of critical genes (laeA, dahp, and trpC) in the shikimate pathway compared with the non-treatment group. In addition, the selection of the feeding rate (0.01 and $0.03g/l{\cdot}h$) was investigated in a 5-L bioreactor. As a result, CHA production was increased by 57.9 mg/l with a $0.01g/l{\cdot}h$ ammonium acetate feeding rate. This work shows that the strategy of ammonium acetate supplementation had an effective role in improving CHA production by Aspergillus fumigatus CY018. It also shows that this strategy could serve as an important example of large-scale fermentation of a marine fungus in submerged culture.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.185-195
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• 2015

Glucoamylase is an important industrial enzyme. Glucoamylase production by industrial Aspergillus niger strain featured with two major problems: (i) empirical substrate feeding methods deteriorating the fermentation performance; and (ii) the high raw materials cost limiting the economics of the glucoamylase product with delegated specification. In this study, we first proposed a novel three-stage varied-rate substrate feeding strategy for efficient glucoamylase production in a 5 L bioreactor using the standard feeding medium, by comparing the changing patterns of the important physiological parameters such as DO, OUR, RQ, etc., when using different substrate feeding strategies. With this strategy, the glucoamylase activity and productivity reached higher levels of 11,000 U/ml and 84.6 U/ml/h, respectively. The performance enhancement in this case was beneficial from the following results: DO and OUR could be controlled at the higher levels (30%, 43.83 mmol/l/h), while RQ was maintained at a stable/lower level of 0.60 simultaneously throughout the fed-batch phase. Based on this three-stage varied-rate substrate feeding strategy, we further evaluated the economics of using alternative carbon sources, attempting to reduce the raw materials cost. The results revealed that cornstarch hydrolysate could be considered as the best carbon source to replace the standard and expensive feeding medium. In this case, the production cost of the glucoamylase with delegated specification (5,000 U/ml) could be saved by more than 61% while the product quality be ensured simultaneously. The proposed strategy showed application potential in improving the economics of industrial glucoamylase production.

• Journal of Periodontal and Implant Science
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• v.30 no.1
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• pp.91-104
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• 2000

Many synthetic bone materials have been studied for their potential of regenerative effects in periodontal tissue. Safflower seeds have been traditionally used as a drug for the treatment of fracture and blood stasis in oriental medicines. The purpose of this study was to assess and compare the osseous responses in rat calvarial defects between bone substitutes such as calcium carbonate and bovine-derived hydroxyapatite and feeding of safflower seeds. The calvarial defects were made with 8 mm trephine bur in 24 Sprague-Dawley rats. Two graft materials were implanted in each experimental groups, whereas the control and safflower seed feeding groups were sutured without any other treatment. And then the rats of safflower seed feeding group were supplied with 3 g/day of safflower seeds. Each group was sacrificed at 4 weeks and 8 weeks. To study a histopathology related to bone healing and regeneration, Goldner's Masson Trichrome stain was done at each weeks. The tissue response was evaluated under light microscope. There were more osteoblastic activity, new bone formation, dense bony connective tissues in bovine-derived hydroxyapatite group compared to other groups at 8 weeks. The osseous defect area of safflower seed feeding group was filled with prominent fibrous tissues, where less inflammatory infiltration and new capillary proliferation. In the early phase of bone healing, safflower seed feeding reduces the inflammatory response and promotes the proliferation of connective tissue. These results suggest that natural bovine-derived HA and safflower seed feeding could enhance the regenerative potential in periodontal defects.

• Journal of Oriental Neuropsychiatry
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• v.9 no.2
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• pp.53-69
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• 1998

This experiment was done to investigate the effects of GAMIKWYBICHONGTANG(GKCT) on the blood and brain tissues of aged rats. The experimental groups were divided into three groups and treated as follows for ten days before administration of scopolamine ; Non treated group(Normal), Distilled water feeding group (Control), GKCT feeding group(GKCT). After feeding them each, Control and GKCT were injected scopolamine for 5 days.We examined the changes of blood cell(WBC, RBC, platelet), blood serum(BUN, creatinine, glucose, uricacid), erythrocyte hemolysis, the activities of cholinesterase, and measured the amounts of malondialdehyde of the blood serum and checked the activities of catalase, SOD of the brain tissues.The results were as follows;1. GKCT showed significant increase of the number of WBC, but those of RBC and platelet didn't significantly changed in comparison with Control.2. GKCT showed significant decrease of BUN, creatinin, glucose, uric acid in blood serum in comparison with Control.3. Erythrocyte hemolysis were decreased significantly in GKCT in comparison with Control.4. About the activity of cholinesterase of blood serum, GKCT showed no significant increase in comparison with Control.5. In TBA reaction to measure the amount of MDA, oxidant material of blood serum of rats, GKCT showed significant decrease in comparison with Control.6. About the activity of catalase of brain tissue, GKCT showed no significant change in comparison with Control.7. About the activity of SOD of brain tissue, GKCT showed significant increse in comparison with Control.According to the above results, GKCT can reduce the formation of free radical and the accumulation of antioxidant materials, it is suggested that GAMIKWYBICHONGTANG(GKCT) has some effects on antiaging. It is also needed more following studies.

• Nutritional Sciences
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• v.7 no.4
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• pp.189-195
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• 2004

1bis study investigated the antioxidative effect in kidney of senescence-accelerated prone SAMP8 mice with calorie restriction. 4-weeks-old SAMP8 female mice were divided into 4 groups according to the experimental feeding period: for 4, 8, 12 month, and at natural death. Each group was subdivided into 2 groups, with thirteen mice each one, as ad libitum group and as dietary restriction group (60% of ad libitum feeding amount). After feeding for a given period, the mice were sacrificed to get the following results: among the experimental groups, there wereno significant differences in xanthine oxidase (XOD) activity in their kidney tissues. The contents of cytochrome $P_{450}$ decreased in ad libitum group and dietary restriction group by age. The activity of NADPH-cytochrome $P_{450}$ reductase showed a trend similar to cytochrome $P_{450}$. Superoxide radical content increased with age. At the 4th, 8th and 12 months of the experimental period, the activity in the dietary restriction group was less than that of ad libitum group by as much as 17% 14% and 14% respectively. For hydrogen peroxide, the contents were increased in the ad libitum group with age, while no correlation between content and age was observed in the dietary restriction group. In the 8th and 12th months of the experimental period, the were in the dietary restriction group less than that of ad libitum group counterpart as much as 17% and 20o/c, respectively. For the cellular membrane stability of the kidney, no significant correlation with age was observed in either the dietary restriction group or the ad libitum group. However at the 12th month of the experiment, however, the stability in the dietary restriction group was 11 % higher than that in the ad libitum group. In conclusion, with these results obtained from the SAMP8 mouse model, we demonstrate that dietary restriction has the effects of anti-oxidation and anti-senescence in the kidney.

• Journal of Nutrition and Health
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• v.12 no.3
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• pp.33-39
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• 1979

The antithiamin activity(ATA) and tannin content were determined for 10 kinds of herbal teas popular in Korea, also on the urinary thiamin excretion and growth rate of rats provided with certain of these teas replacing water. The results are summarized as follows: 1) The tea bag and IT-A had higher ATA (mg thiamin destroyed/g tea), while GT-A and Omiza-tea had lower activity. Different brands of the teas refulted in extremelw different ATA ana tannin content. 2) The body meight gain in the feeding groups of GT-B and GE-B were a little lower than that of the feeding groups of water, LT and IT-A, but these differences were not significant. 3) The food consumption, the food efficiency and the drink consumption of all groups for the total feeding term were not significant. 4) The thiamin excretion was higher in the LT, GT-B groups but lower in the If-A group -when compared to the water group, none of these results were significant.

• Journal of Aquaculture
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• v.10 no.2
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• pp.213-218
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• 1997

Experiments on the feeding activity and environmental tolerance of geoduck clam, Panope japonica caught at the coastal water of Kangwon province located in the East Sea of Korea were performed from January to December, 1994. Twenty genera and 33 species of plankton were found in the digestive tract, and most of them are phytoplankton. In spring, 21 species of planktonic foods were indentified, but in sumer, only 11 species were identified. Nitzschia longissima and Rizosolenia alata were present evey month. Weight of the digestive tract was fluctuate seasonally : higher winter and spring, and lower summer. Adult geoduck clams could be tolerated within the range of 5 to $20^{\circ}C$ water temperature, and they could tolerated considerably well temperature than higher temperature within the range.

• Korean Journal of Ichthyology
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• v.31 no.1
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• pp.54-61
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• 2019

A study on the diel activities and feeding habits of Pseudobagrus brevicorpus living in the Daegacheon Stream of Nakdonggang River was conducted in September 2017. Diel activity took place during the night, just after sunset and just before sunrise. Pseudobagrus brevicorpus swam in the middle depths, and when they found prey organisms, approached and consumed them immediately. Fish were divided by age into three groups. Prey organisms whose index of relative importance in the stomach contents exceeded 1% belonged to the orders Ephemeroptera (80.8%), Diptera (8.6%), and Trichoptera (8.5%). An index of relative importance by age showed that the Ephemeroptera are very important prey organisms, and the sizes of prey organisms increase with fish growth.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.175-182
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• 2010

Two insecticides, fenobucarb (36, 12 ppm) and imidacloprid (0.7, 0.4 ppm) were treated on rice seedling roots by root uptake method with different dipping time (1, 4, 8, 12, 16, 20, 24 hrs). This study was performed to elucidate the correlation between insecticidal activity and feeding behavior of Nilaparvata lugens using EPG (electrical penetration graph). EPG waveforms are recorded for 4 hours and classified into six waveforms. In the correlation between root uptake and corrected mortality, both insecticides showed higher corrected mortality as higher doses and as longer root uptake times. In the analysis of waveforms, N. lugens showed longer nonprobe time but shorter phloem feeding time at a higher dose. It was also showed the same result as longer the root uptake times. Therefore, it showed the correlation between insecticidal activity by root uptake time and both EPG waveforms (non-probing time and phloem feeding time).

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.124-135
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• 2003

In order to prevent pollution from animal waste, the excretion of nutrients should be reduced through proper nutritional management. Among the many nutrients of concern, such as N, P, Cu, Zn and K, P is one of the most concerned nutrients to be managed. Seven feeding trials, three with layers and four with broilers, were conducted to determine if microbial phytase supplementation can reduce non-phytate phosphorus (NPP) level in diets and results in concomitant reductions of P excretion. The results showed that microbial phytase can be successfully used to achieve these purposes. Activity of natural phytase in certain plant feedstuffs is high enough to be considered in feed formulation. Three experiments have been conducted to study the characteristics of plant phytase and its application to feeding of broilers. Selected brands of wheat bran could be successfully used as a source of phytase in broiler feeding.