• Journal of Nutrition and Health
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• v.26 no.8
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• pp.933-941
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• 1993

The present study was carried out to investigate the effects of magnesium supplement levels and periods on lipid metabolism in male Sprague-Dawley rats given low protein and magnesium deficient diets. The effect of magnesium supplement levels and periods on lipid metabolism in rats given a low protein and magnesium deficient diet for 2 weeks were investigated. Serum total lipid and triglyceride contents were significantly lower in magnesium supplement group compared with magnesium deficient group. Serum HDL-cholesterol/total cholesterol ratio was significantly increased as magnesium supplement level was increased. Liver total lipid, triglyceride, total cholesterol and phospholipid contents were significantly lower in magnesium supplement group than those in magnesium deficient group. Serum ALP, GOT and GPT activities were significantly decreased in magnesium supplement group compared with magnesium deficient group. In summary, the effect of magnesium supplement on lipid metabolism and enzyme activities were significant and we can see that magnesium supplement level propered to be requirement level(400 mg/kg diet)in the other cases except serum lipid contents.

• Journal of Aquaculture
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• v.12 no.2
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• pp.145-153
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• 1999

This study was conducted to determine the protein requirement of ayu (Plecoglossus altivelis). Two replicate groups of fish initially averaging 6.6 g were fed the five isocaloric diets containing different protein level from 29% to 57% in a flow-through freshwater system for 25 days. White fish meal was used as a sole protein source. Weight gain and feed efficiency of fish increased significantly with dietary protein level up to 43% (P＜0.05) with no additional response above this level. Protein and lipid retention, moisture, protein and lipid contents of body were not affected by dietary protein levels (P>0.05). Daily protein intake increased significantly with dietary protein level, whereas protein efficiency ratio of fish fed the 57% dietary protein decreased (P<0.05). The data obtained in this study indicate that a 43% dietary protein level could be recommended for the optimum growth of ayu.

• Journal of Photoscience
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• v.1 no.2
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• pp.83-88
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• 1994

The synergic effect of iron plus blue light on the peroxidation of membrane lipid was investigated, using liposomes made of phospholipid. While strong irradiation did not affect Fe$^{+2}$-promoted lipid peroxidation that turned out to be O$_2$-dependent, ferric iron in bright light exerted a pronounced effect on the initiation of lipid peroxidation: this combined action of light and Fe$^{+3}$ on liposomal membranes was apparently independent of O$_2$. When liposomal samples containing Fe$^{+3}$ were subjected to irradiation, some portions of Fe$^{+3}$ were converted into Fe$^{+2}$. The extent of the Fe$^{+3}$-Fe$^{+2}$ conversion increased with increasing time of irradiation, which resembled the dependence of Fe$^{+3}$-promoted lipid peroxidation on irradiation. Further, it was observed that the effect of irradiation in liposomal samples containing Fe$^{+2}$ was strikingly mimicked by that of Fe$^{+2}$ addition to the same samples. The obligatory requirement of a suitable Fe$^{+3}$/Fe$^{+2}$ ratio for the genesis of iron-dependent lipid peroxidation, a controversial proposition, was also confirmed by the observation that lipid peroxidation was substantially enhanced by the addition of a mixture of Fe$^{+3}$ and Fe$^{+2}$, as compared to the addition of Fe$^{+3}$ or Fe$^{+2}$ alone. The results obtained in this study not only suggest that light acts as an effector for initiating lipid peroxidation, when Fe$^{+3}$ is present in membrane systems, but also imply that any chemical or physical factor that influences the redox states of iron in membranes can play a role in lipid peroxidation reactions.

• Journal of Nutrition and Health
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• v.43 no.3
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• pp.315-323
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• 2010

The purpose of this study was to establish the selection of indicators for estimating and factors affecting the requirement of vitamin B6. There has been a need to establish the human requirements of vitamin $B_6$ since vitamin $B_6$ is thought to be involved in more than one hundred biochemical reactions as a coenzyme in the metabolism of amino acids, glucose, and lipid, and the synthesis of neurotransmitters. For the review of the literature, this study included from early findings of the sixties to studies of 2009. This study suggests that plasma pyridoxal 5' phosphate (PLP) is the best single indicator of vitamin $B_6$ status for the healthy but not for the non-healthy. Erythrocyte aspartate aminotransferase and alanine aminotransferase activation by PLP as an indirect measure and urinary 4-pyridoxic acid excretion as a direct measure are useful as supporting indicators. Bioavailability, nutrient interaction, physiological need, and chronic diseases may increase the requirement for vitamin $B_6$. However, these effects can not be quantified due to insufficient evidences.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.180-186
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• 1998

A 10-week feeding experiment was conducted to determine the phosphorus requirement of juvenile Korean rockfish (Sebastes schlegeli). Three replicate groups of fish initially averaging 4.2g were fed the semipurified experimental diets containing graded levels of $NaH_2PO_4\;\cdot\;2H_2O$ to provide from $0.1\%$ to $1.32\%$ total phosphorus level in a flow-through seawater system. Korean rockfish muscle and casein were used as the protein sources of the basal diet. Weight gain, feed efficiency and protein retention of fish fed the $0.35\%$ phosphorus were higher than those of fish fed the $0.1\%$ phosphorus, although no significant improvements $(P>0.01)$ were observed above the level. Determined phosphorus requirement using the broken line model was found to be $0.3\%$ for weight gain. Moisture, protein and lipid contents of whole body and muscle were not affected by dietary phosphorus levels $(P>0.01)$. Lipid contents of liver in fish fed the $0.1\%$ phosphorus were lower than those in fish fed the $0.35\%$ and $1.32\%$ phosphorus $(P<0.01)$. Dietary phosphorus increased ash and phosphorus contents of the whole body, while those of bone were not affected $(P>0.01)$. The data obtained in this study indicate that a $0.3\%$ dietaryphosphorus level could be recommended for the optimum growth and efficient nutrient utilization of juvenile Korean rockfish.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.2
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• pp.100-106
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• 2002

The purpose of this study was to investigate the effect of copper and selenium supplementation on lipid contents. Lipid levels in serum and liver were analyzed and compared in rats fed diet with 100, 200 and 400% of copper requirement and 100% and 1000% of selenium requirement for 6 weeks. Feed intake, body weight gain, and feed/weight were not significantly different among the groups. Serum cholesterol was the lowest in the copper-adequate group and sect LDL-cholesterol was significantly lower in the selenium-adequate group compared to the selenium-supplement group. Liver cholesterol was significantly elevated by the supplementation of copper and selenium. Summarizing these results, with the supplementation of copper and selenium, cholesterol levels in serum and liver increased in rats. Therefore, it could be suggested that adequate intake of minerals and well-balanced diet are more desirable than nutrient supplementation.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.1
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• pp.7-12
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• 1988

Twenty cows, by order of calving, were used in a completely randomized $2{\times}2$ factorial experiment. Variables were tow protein levels (14 and 18% crude protein) and concentration of fat (2 and 6% ether extract) in diets. Fat addition, via unprocessed whole sunflower seed, insured forage utilization in diets to meet energy requirement of cows. A total of 36 wks of lactation was subdivided into three 12-wk stages of lactation. Net energy lactation was set at 1.72, 1.57 and 1.42 Mcal/kg for each stage. Higher protein diets improved the efficiency of energy (FCM/net energy intake) which was particularly noted for diets containing high fat (85.7%). However, diets with low protein-high fat resulted in the lowest efficiency (67.7%). No difference in milk yield and butterfat was due to different levels and combinations of protein and lipid in diets. High protein diets depressed blood cholesterol and glucose compared to low-protein counterparts. Relative decline in milk production was slower for lower fat diets than for higher fat groups, especially mid to later stage of lactation. Results of this experiment tend to support our thesis on the synergistic effect of dietary protein and energy (lipid) upon efficiency of lactation.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.1
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• pp.9-19
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• 1998

The purpose of this study was to investigate the effect of calcium intake on lipid contents and enzyme activities in rats of different ages. Lipid levels in serum and liver and GOT, CPK and LDH activities in serum were compared in rats of different ages(4 weeks and 10 months) that were fed various levels of calcium(50, 100, 200% of requirement)for 3 weeks. Body weight gain and feed efficiency ratio were significantly higher in young rats than in adults. Serum calcium level was increased by elevation of calcium intake levels were decreased. Liver phospholipid and triglyceride levels in the high-cal-terol and triglyceride levels were decreased. Liver phospholipid and triglyceride levels in the high calcium group were significantly lower than those in other groups. Serum GOT and LDH activities of adults were significantly higher in low-calcium group than those in adequate/high-calcium groups. However, serum CPK activity of adults was significantly higher in high-calcium group than that in low/adequate-calcium groups. The results of this study suggest that adequate calcium intake may have protective effects ont he alteration of lipid and enzyme activity in rats.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.369-374
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• 2012

A $3{\times}2$ factorial experiment was conducted to determine the effects of dietary protein and lipid levels on the growth and body composition of juvenile far eastern catfish. Six diets were formulated to contain three levels of protein (20%, 30% and 40%) and two levels of lipid (9% and 17%). Triplicate groups of fish (initial body weight of 7.6 g) were hand-fed to apparent satiation for 66 days. Final mean weight was improved with increasing dietary protein and lipid levels, and the highest final mean weight was observed in fish fed the 40/17 (% protein/% lipid) diet. No significant difference was observed in final mean weight for fish fed between 30/17 diet and 40/9 diet. Feed efficiency of fish fed the diets containing over 30% protein levels with 9% and 17% lipid levels were significantly higher than those of fish fed the 20% protein levels. Feed efficiency of fish fed the 30/17 diet was not significantly different from that of fish fed the 40/9 diet or 40/17 diet. Feed efficiency and protein efficiency ratio of fish fed the 20% protein diets with 17% lipid level were significantly higher than those of fish fed 9% lipid diet. Daily feed intake of fish tended to decrease with increasing dietary protein and lipid levels. Moisture content of whole body in fish fed the 9% lipid diets was significantly higher than that of fish fed the 17% lipid diets at the same protein level, but the opposite trends were found for crude lipid content. Significant effects of dietary lipid were observed for most fatty acids, according to their relative values in the diets. The results of this study suggest that the protein requirement for maximum growth of juvenile far eastern catfish may be higher than 40%, and an increase of dietary lipid level from 9% to 17% can improve growth and feed utilization.

• Journal of Aquaculture
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• v.13 no.3
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• pp.207-213
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• 2000

Five diets, containing different levels (0.3-1.5%) of n-3 highly unsaturated fatty acids (n-3HUFA) adjusted by adding different ratio of squid liver oil and soybean oil to 8% lipid, were fed to the rockfish (130 g) for 8 weeks. Mean weight gain and feed efficiency were lowest in the fish fed the diet containing 0.3% n-3HUFA. These values improved with increasing squid liver oil, and showed linear relation up to 0.6% n-3HUFA, Using the brocken line model, the dietary n-3HUFA requirement was estimated as about 0.9 % for optimal weight gain of the fish. Crude lipid levels of the liver in 0.3-0.6%) n-3HUFA diets were significantly higher than in the 1.5% n-3HUFA diet (P<0.05). Fatty acid composition of polar lipid in the liver were directly affected by dietary lipid sources. The level of n-3HUFA of polar lipid in the liver increased with dietary n-3HUFA levels, although 18:2n-6 content decreased. Hence the n-3HUFA requirement of a growing rockfish is 0.6-0.9% of diet.