• Development and Reproduction
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• v.5 no.1
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• pp.1-8
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• 2001

Golden hamsters show the reproductive activity that is determined by the photoperiod (length of light per day). Photoperiod is an environmental factor that is predictable through an entire year. The hamsters are sexually active in summer during which day length exceeds night time. The critical length is at least 12.5 hours of light in a day where reproductive function is maintained. The information of photoperiod is mediated by the pineal gland because removal of pineal gland blocks the influence of photoperiod on reproductive activity. The hamsters without pineal gland maintain sexual activity and promote it in a situation that suppresses gonadal activity. The pineal gland secretes melatonin that reflects the photoperiod. The appropriate administrations of melatonin into both pineal intact and pinealectomized hamsters lead to a gonadal reression. The results suggest that melatonin constitutes a part of control mechanism whereby environmental information is transduced to neuroendocrine signal respensible for the functional integrity of the reproductive system. Despite of the intense studies, the action site of melatonin is on the whole unknown. It is mainly due to the lack of acute efffct of melatonin on the secretion of reproductive hormones. However, sexually regressed animals display the low levelsof gonadotropins and the augmentation of the hypothalamic gonadotropin-releasing hormone (GnRH) content, implying that the antigonadotropic effects either by photoperiod and/or by the treatment of melatonin are mediated by the GnRH neuronal system. The action mechanism by which melatonin exerts its effect on GnRH neuron needs to be investigated. Recent cloning of melatonin receptor will contribute to examine various and putative potencies of melatonin via its anatomical identification and the action mechanism of melatonin on target tissues at the molecular level.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.228-233
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• 2009

This study was conducted to examine the changes in the molecular structure and physiological activities of silk fibroin by gamma irradiation. The results of gel permeation chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the molecular weight of fibroin was increased depending upon the irradiation dose. Secondary structure of fibroin determined by using circular dichroism revealed that the ratio of $\alpha$-helix was increased up to 10 kGy and then decreased depending upon the irradiation dose. Whereas, the ratio of $\beta$-sheet, $\beta$-turn, and random coil were decreased and then increased with an alteration in the $\alpha$-helix secondary conformation. The 2.2-diphenyl-1-picryl-hydrazil (DPPH) radical scavenging activity of fibroin was increased by gamma irradiation at 5 kGy, but was decreased above 10 kGy depending upon the irradiation dose. Also, the inhibition activities of tyrosinase and melanin synthesis of fibroin were increased by gamma irradiation. These results indicated that gamma irradiation could be used as an efficient method to make fibroin more suitable for the development of functional foods and cosmetics.

• Korean Journal of Food Science and Technology
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• v.47 no.3
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• pp.373-379
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• 2015

This study aimed to investigate the anti-amnesic effect of perilla oil against trimethyltin (TMT)-induced learning and memory impairment in ICR mice. Perilla oil (2.5 mL/kg of body weight) and soybean oil (2.5 mL/kg of body weight) were administered orally to mice for 3 weeks, and at the end of the experimental period, cognitive behavior was examined by Y-maze and Morris water maze (MWM) tests. Behavioral tests showed that the mice treated with perilla oil had improved cognitive function compared to that in mice administered soybean oil. Analysis of brain tissue showed that perilla oil significantly lowered acetylcholinesterase activity and malondialdehyde (MDA) levels. Oxidized glutathione (GSH)-to-total GSH ratio also decreased from 10.4% to 5.3% in perilla oil-treated mice, but superoxide dismutase (SOD) activity increased from 11.7 to 14.2 U/mg protein. Therefore, these results suggest that the perilla oil could be a potential functional substance for improving cognitive function.

• Journal of The Korean Society of Integrative Medicine
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• v.1 no.2
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• pp.23-35
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• 2013

Purpose : We intend to make the study date for an effect of therapy by comparing the functional level both before and after conducting handwriting training and strength training as a part of treatment to improve muscle strength and function of the patient's non-dominant hand. Method : 8 subjects in writing training group conducted hand writing training 30 minutes at once and three times a week for 4 weeks in total 12 times, and 8 subjects in muscle training group conducted muscle training program of putty and Rolyan ergonomic hand exerciser for 15 minutes respectively in sum up 30 minutes at once and three times a week for 4 weeks in total 12 times. 8 subjects in control group are not applied any training for 4 weeks. Results : It was much more effective in handwriting training than muscle strength training by Grooved pegboard because this study showed the speed decrease from 67.11 to 58.26 seconds in handwriting compared with muscle strength training which showed 5.22 seconds decrease from 67.54 to 62.32(P<.05). It showed about 1.34 muscle strength improvement from 6.60 to 7.94 in handwriting training and 0.92 improvement of muscle strength from 7.04 to 7.96 in muscle strength training by 3-jaw chuck pinch, so handwriting training was more effective(P<.05). It showed 11.58 seconds decrease in handwriting training from 26.62 to 18.01 seconds and 10.93 seconds decrease from 27.43 to 16.50 seconds in muscle strength training, so it was significantly shortened both in handwriting and muscle strength training(P<.05). Conclusion : Dexterity, muscle strength, and handwriting ability of non-dominant hand could improve both the handwriting training and the muscle strength training.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.367-375
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• 2013

Kalopanax pictus has pharmacologically anti-inflammatory and analgesic effect and is known to respond to treatment of backache, knee pain and etc. In this study, we investigated the effects on gastric lesions of Kalopanax pictus both from Korea (KPK) and China (KPC) compared with their related origin, Znthoxylum ailanthoide both from Korea (ZAK) and China (ZAC), and Korean Bombax malabaricum (BMK). In preliminary screening, KPK and KPC shown effective inhibition of HCI EtOH-induced gastritis in rats. To elucidate their protective effects on gastric lesions, we assessed inhibition of H. pylori colonization, 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging activities, reducing power test, and inhibition of lipid peroxidation. KPK was the most effective from antioxidant assays. KPK also shown the inhibition of indomethacin-induced gastric ulcer in rats. Gastric secretion in rats, KPK reduced the secretion of gastric juice and total acidity and raised pH. Therefore, it is possible that KPK can be developed as health functional food and natural medicine. In addition, it can contribute to the standardization with objectivity and reliability for KPK through the criteria establishment of the precise origin of medicine, the prevention of indiscriminate distribution of imitation, and the rising rate of dependence on imports of medicinal herbs, and mixing prevention of low-quality goods.

• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.337-341
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• 2013

After it was known that an antioxidant function was associated with a reducing risk of cancer and cardiovascular disease, a large number of plant have been investigated for their antioxidant activity. However, lacking of the extensive antioxidant data in vegetables, a few natural antioxidant was used in the food industry. Therefore, this study was carried out to provide some scientific antioxidant activity data in the various vegetables. The samples (n = 275) including 24 kinds of vegetables were examined for antioxidant activity. Total Phenol Contents (TPCs) were measured colorimetric determination method using the Folin-Ciocalteu reagent by gallic acid as the control group. DPPH radical scavenging activity were also investigated using calculation of $IC_{50}$(concentration of extracted needed to inhibit 50% of the DPPH radical). The contents of TPCs were $0.32{\sim}49.26{\mu}g/kg$ and DPPH radical scavenging activity ($CI_{50}$) was 0.0~2.43 mg/mL in vegetables. The best antioxidant effect was shown in Garlic for both antioxidant assay methods.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.180-185
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• 2003

Rats(Sprague-Dawley) were randomly assigned to the following four groups, control, exercise only, exercise and the intake of DNA, exercise, and the intake of DNA plus crude catechin. 0.4% of DNA from salmon egg and 0.1% crude catechins from Puerariae thunbergiana roots were fed to the rats. The exercise group was exercised in a treadmill at 20 m/min speed for 6 wks. Body weight and body fat weight of 4 groups were investigated, and the body fat composition and antioxidant activity were evaluated by measuring the weight of organs and biochemical test. After 6 wks, body weight did not show any significant differences among those 4 groups, but body fat weight in exercised groups was significantly decreased. The weight of liver, epididymal adipose tissue(E.A.T) and perirenal adipose tissue(P.A.T) were significantly decreased in groups of exercise only, exercise and the intake of DNA, exercise and the intake of DNA plus crude catechin(p<0.05). Phospholipid, cholesterol and triglyceride levels of serum were decreased by exercise, but HDL-cholesterol level of serum was significantly increased(p<0.05). GOT, GPT and glucose levels in serum were slightly decreased by crude catechin, but serum NEFA levels were significantly increased by crude catechin(p<0.05). Results indicated that excercise with the intake of crude catechin would be helpful for the functional development of the compositions in blood lipid.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.257-262
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• 2006

This experiment was carried out to investigate the effect of hypoglycemic yogurt as a clinical test with person both who have diabetes and who don't have diabetes. Diabetes is a disease caused by unused and accumulated glucoses produced via the foods digestion due to the lack of insulin or lower tissue reaction to insulin. Patients with diabetes or complications of diabetes are on the rise annually. For the therapy and prevention of diabetes, a yogurt made from functional materials such as insulin-resistant FK-23 lactic acid bacteria, Pinitol, edible fiber which delays glucose-absorption, extract powder of glucose-absorption-inhibitory white bean and low-caloric Erythritol and banaba extract is effective for reduce or restrain the blood glucose levels. The blood glucose levels after a meal of non-diabetic persons were lower after drinking a hypoglycemic yogurt than they after drinking general yogurt. The blood glucose levels after a meal of 10 diabetic patients were checked after drinking the yoghurt. As a result, 19 mg/dL, 30 mg/dL, 31 mg/dL of blood glucose levels decreased in 30 min, 60 min and 120 min respectively after drinking the yogurt. Blood glucose inhibition rates of 80 % of the tested patients also decreased. The blood glucose level of the diabetic patients having drunk the yogurt for 30 days consistently decreased into 59 mg/dL in 120 min after a meal.

• Journal of Dairy Science and Biotechnology
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• v.34 no.4
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• pp.263-270
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• 2016

This study was carried out to evaluate the antioxidant activity and total polyphnol content of Greek-style yogurt in 12% solid content with added stevia leaf extracts. Stevia leaf extracts used as sweetener in preparing Greek-style yogurt were prepared in hot water ($100^{\circ}C$ for 6 h 3 times, and by 70% fermented ethanol for 24 h at room temperature 3 times). The antioxidant activities were measured by assessing the radical scavenging effect through DPPH, ABTS, and FRAP assays. To identify the compounds present, total polyphenol content was evaluated using a Folin-Dennis assay. The capability to scavenge free radicals and total polyphenolic content were the highest in Greek-style yogurt containing 1% stevia extract and fermented in 70% ethanol. According to the results, antioxidant activities significantly increased when high concentration of stevia extracts were added to the yogurt (p<0.05). Therefore, these results suggest that stevia leaf extracts can be used as a source of functional compounds in Greek-style yogurt. We also suggest that fermented ethanol extraction can be used to obtain stevia leaf extracts.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.605-610
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• 2013

Gamma-aminobutyric acid (GABA) is a non-protein amino acid widely present in organisms, which has shown several important physiological functions such as neurotransmission, hypotension induction, as well as diuretic and tranquilizer effects. They have also been extensively used in food industry. GABA contents in the grain and brown rice are about 1~4 mg/100 g and 4~8 mg/100 g, respectively but it is difficult to expect physiological activity from such low amounts of natural food intake. We investigate the effects of GABA-coated rice on the secretion of melatonin and serotonin which both have been used as sleep inductive compounds. As a result, the secretion of melatonin and serotonin from mice were found to be $3.578{\pm}0.158pg/mL$, $5.918{\pm}0.169ng/mL$ respectively. The melatonin and serotonin in mice increased significantly up to the 8.7 and 22.8 times respectively, when compared to that of the rice, but there was no cumulative effects. Due to the continuous intake of GABA-coated rice, which was developed as a functional food nutrient, inductive effects of melatonin and serotonin from general rice could be achieved and also the similar effect as taking up directly 25 mg/mL of GABA could be obtained.