• Journal of Nutrition and Health
• /
• v.23 no.7
• /
• pp.504-512
• /
• 1990

In experiment 1, dietary self-selection of the 3 macronutrients, protein, fat, and carbohydrate were examined in male rats given 3 food cups of 80% carbohydrate, 80% protein, and 70% fat diets simultaneously. All the rats showed normal growth pattern and organ weight, which means they have ability to select just right kinds and amounts of nurients in order to support their growth and development. Mean values of caloric intake, body weight gain, serum lipid values and empty carcass compositions were not significantly differ between the upper and lower quartile groups of fat proportion of empty carcass compared to the lower quartile group(LF). Same feeding design was employed in experiment 2 where the effect of mild electric stress on food selection was studied. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The stress group showed higher caloric intake and body weight gain than control group, but no significant effects of stress on serum and empty carcass components was found. Even though normal rats seemed to select macronutrients according to their physiolosical needs, there were individual differences in food selection whether they were exposed to stress or not. Therefore life long individual food selection pattern may have a great influence on nutritional status and chronic degenerative diseases of eldery, and on aging process.

• Korean Journal of Food Science and Technology
• /
• v.26 no.5
• /
• pp.490-495
• /
• 1994

Enzymatic solubilization of tofu-residue was attempted using carbohydrase isolated from Aspergillus niger CF-34. Tofu-residue, by-product of tofu manufacture or soymilk processing was used as the model for plant cell wall. It was found that tofu-residue was rich in nurients: 46.7% carbohydrate, 32.8% protein, the rest being lipid and ashes. Carbohydrate component of tofu-residue consisted of 36.8% cellulose and 62.6% hemicellulose. The carbohydrase was found to consist of pectinase, xylanase, PGase, CMCase, and SFase when tofu-residue and pectin were used as the carbon source. Enzyme induction was maximum at 7days of culture. Optimum reaction pH was 4.0, temperature $50^{\circ}C$. The enzyme was stable to $50^{\circ}C$, above which the stability decreased rapidly.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.7 no.3
• /
• pp.129-139
• /
• 2002

We investigated the outbreak of red tides dominated by harmful dinoflagellates from August to November 1999 in the coastal waters off the southern Saemankeum areas where a huge red tide dominated by Cochlodinium polykrikoides had been first observed in 1998. We took water samples from 2~5 depths of 4 stations (with 3-4 additional stations during red tides) in this study period and then measured the abundance of phytoplankton, water temperature, salinity, and the concentrations of nutrients. In the study period harmful dinoflagellates Alexandrium tamarense, C. polykrikoides, Gymnodnium catenatum, Gyrodinium aureolum, Gymnodnium impudicum were present, and of these G. aureolum and C. polykrikoides formed red tide patches on September 16 and October 18, respectively. The date of the outbreak of red tide dominated by C. polykrikoides in the study area was approximately 50 days later than that off the Kohung areas in 1997 and the surface water temperature when the red tides outbroke in the former area was 6$^{\circ}C$ lower than that fur the latter area. The maximum abundance of C. polykrikoides on September 16, October 7 and 18 were 5, 14, and 463 cells $m\ell$$^{-1}$ , respectively. The growth rate of C. polykrikoides, isolated from the study area, was 0.3~0.4 d$^{-1}$ at 20~$25^{\circ}C$, which enable this species to reach the maximum concentration without being transported from the adjacent waters containing already made red tide patches. The outbreaks of red tides dominated by C. polykrikoides in the study area and off Kohung have occurred when and/or where the concentrations of diatoms were low. This evidence suggests that the outbreak of red tides dominated by C. polykrikoides is adversely affected by the high diatom concentrations or the conditions favorable for the growth of diatoms.