• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.731-743
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• 2018

This study was performed to test the feasibility of thermophilic ($55^{\circ}$) co-digestion of municipal sewage sludge and food wastes. The management variables of co-digestion were the mixed ratios of municipal sewage sludge and food waste hydraulic retention times (HRTs). During the operation of thermophilic co-digestion, the reactor pH ranged from 7.0 to 7.5 and the reactor alkalinity remained above 3,200 to 4,000 mg/L as $CaCO_3$. The volatile fatty acids concentration increased as the HRT shortened from 20 days to 10 days and the mixture ratio increased to 1:4, but did not reach toxic levels for co-digestion of sewage sludge and food wastes. Methane productivity increased gradually as the organic loading rate increased. Maximum methane productivity reached 1.03v/v-d at an HRT of 10 days and at the mixture ratio of 1:4. The TVS removal efficiency decreased from 70.6% to 58.3% as the HRT shortened from 20 days to 10 days. TVS removal efficiency ranged from 57.0% to 77% during the entire operation. It is likely that thermophilic co-digestion of sewage sludge and food wastes is a very effective method both to environmentally treat food waste and to economically produce gas for energy.

• Journal of Ecology and Environment
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• v.44 no.1
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• pp.45-53
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• 2020

Background: The black soldier fly (Hermetia illucens) is gaining attention as an efficient decomposer of food waste. However, recalcitrant compounds such as plastics mixed into food waste may have negative effects on its growth and survival. Moreover, its efficiency of food waste degradation may also be affected by plastics. In addition, salt (NaCl) can also be present in high concentrations, which also reduces the efficiency of H. illucens-mediated food waste treatment. In this study, we assessed the growth of black soldier fly larvae (BSFL) reared on food waste containing polyethylene (PE) and polystyrene (PS) and NaCl. The weight of BSFL was measured every 2-4 days. Survival and substrate reduction rates and pupation ratio were determined at the end of the experiment. Results: The total larval weight of Hermetia illucens reared on food waste containing PS was greater than that of the control on days 20 and 24. However, the survival rate was lower in the group treated with 5% PS, as was substrate reduction in all PS-treated groups. The weight of BSFL reared on food waste containing PE was lower than that of the control on day 6. PE in food waste did not affect the survival rate, but the pupation ratio increased and substrate consumption decreased with increasing PE concentrations. Regardless of the plastic type, the addition of NaCl resulted in decreased larval weight and pupation ratio. Conclusions: Larval growth of black soldier fly was inhibited not by plastics but by substrate salinity. Additional safety assessments of larvae reared on food waste containing impurities are needed to enable wider application of BSFL in vermicomposting.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.65-69
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• 1977

The characteristics of two stage compressor which is constituted of two separated reciprocating compressors was tested measuring the volumetric efficiency of each compressor at suction of both bighandlowpressdresideusillgorificetypeflolrmeters. The volumetric efficiency of low pressure side compressor was lower than that of the high side when they were operating under the same compression ratio. And it tended to reduce obviously by lowering evaporating temperature resulting in a markable reduction of refrigerating capacity at the same time. It is assumed that the falling of volumetric efficiency at low side compressor was directed by the decrease in evaporating temperature which derives the falls of gas pressure at suction, increase in compression ratio, and gas flow resistance at suction and discharge valves.

• Journal of Nutrition and Health
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• v.24 no.1
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• pp.20-29
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• 1991

This study was carried out to compare the protein quality of lamb and beef meat. by feeding to growing rats. Sixty weanling rats, 30 males and 30 females, were blocked into 12 groups(6 gruops of males and 6 groups of females). They were fed casein. beef, or lamb as a protein source at two levels, 6 and 15%, for 5 weeks. The amount of food intake. food efficiency ratio, protein efficiency ratio. body weight gain. and the weights of skeletal muscles and liver were measured. Nitrogen retention, protein content in the liver and skeletal muscles, and the levels of protein and cholesterol in the serum were also assayed. Summarzing the results, there were no significant differences between lamb and beef on the growth and nitrogen utilization in the rats fed same percentage of protein diet. However. rats fed 15% protein diet showed significantly higher growth rate than those fed 6%. Therefore, it can be concluded that lamb is as good a protein food as beef in terms of protein quality.

• Journal of Life Science
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• v.11 no.4
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• pp.298-303
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• 2001

The hypolipidemic effect of the diet containing uncooked food was evaluated in hyperlipidemic rats. Body weightgain, food intake and food efficiency ratio were not significantly different among the diet groups examined. Significant decrease in plasma total cholesterol(8.8%), triglyceride(10.0%) and LCL-cholesterol(34.8%) were observed in uncooked food diet groups, and the liver total cholesterol and triglyceride level to the extent of 8.7% and 16.7%, respectively. Uncooked food groups substantially increased the plasma HDL to total cholesterol ratio(47.2%) and decreased the atherogenic index(37.6%) as well. Gut transit time for uncooked food was significantly higher, up to 104 minutes, compared to that of control diet group. These results suggest that uncooked food may have beneficial effects on blood lipid level and gut transit time in hyperlipidemc rats.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.1
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• pp.1-12
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• 2005

Feed conversion efficiency contributes directly or indirectly on the cost benefit ratio of silkworm rearing and is considered to be an important physiological criterion for evaluating the superiority of silkworm breeds/hybrids. Food intake, assimilation and conversion of indigenous as well as exotic silkworm races are well studied by many researchers. In this review, an attempt has been made to consolidate works on feed conversion aspects of indigenous and exotic silkworm races. The paper also deals with the effect of various factors viz., nutritional, environmental and feeding on food assimilation and conversion parameters of mulberry silkworm.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.610-615
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• 2020

Edible insects might be used as a means to solve food insecurity caused by population growth. Many studies have investigated the biological activity of insects; however, few studies have investigated the nutritional value of insects. Therefore, the aim of this study was to investigate the nutritional value of Allomyrina dichotoma larva protein (ADP) as a source of protein replacement. In vivo studies were conducted to determine the food efficiency ratio (FER), protein efficiency ratio (PER), and true digestibility (TD) of ADP. Experiments were conducted in 3 groups of 8 animals per group using twenty-four 4-week-old SD rats. The experimental groups included the general diet group (Con), in which 20% of the total Kcal in the diet was composed of casein protein, and the ADP group (ADP), in which 20% of the total Kcal was composed of ADP protein, and a non-protein diet group (NP) to measure the protein (metabolic fecal nitrogen) excreted by metabolic processes in the body. As a result of this experiment, we found that the FERs were 0.52 and 0.41 in the casein protein intake (Con) and ADP groups, respectively, thus showing a significantly lower level in the ADP group. The PERs of ADP and Con were 2.39 and 2.63, respectively. The TD of Con and ADP were 91% and 80%, respectively.

• Journal of Food Hygiene and Safety
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• v.10 no.3
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• pp.163-168
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• 1995

The present study has been undertaken to investigate the effects of garlic added to food on the activities of several enzymes in serum of rats fed lard and alcohol. Thirty-five males of Sprague-Dawley strains weighed about 130g were divided into 7 groups, each group receiving a different diet for 10 weeks; i.e. basal diet plus 15% lard, basal diet plus 5% alcohol, basal diet plus 0.5% garlic, basal diet plus 15% lard and 0.5% garlic. Determinations were carried out in the net weight gain, food efficiency ratio, weight of organs, and AST, ALT, lactate dehydrogenase, alkaline phosphatase activities in serum of rats. The results obtained were as follows; Rats given feed containing lard and alcohol showed significant decrease in net weight gain, but garlic caused an increased in food efficiency ratio. Lard supplementation caused an increase in the weight of liver, kidney, spleen, but another groups did not, AST, ALT, ALP, LDH of serum were significantly increased in lard and alcohol containing group but garlic feeding decreased enzyme activities compared to lard and alcohol containing group. The above results suggest that garlic would prevent the metabolic disease of liver by improving hyperlipemia caused by high fat diet.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.3
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• pp.363-371
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• 2010

The purpose of this study was to examine the impact of caffeine on lipid concentrations in ovariectomized rats. Forty-four rats (75${\pm}$5 g) were randomly divided into ovariectomy(ovx) and sham groups, each of which were randomly divided into two subgroups that were fed the control diet or a caffeine-supplemented diet (0.03%/diet). The experimental groups were classified into 1) sham-control, 2) sham-caffeine, 3) ovx-control and 4) ovx-caffeine groups. All rats had been fed on experimental diet and deionized water ad libitum for 6 weeks. Triglyceride concentration and total cholesterol were measured in serum and liver. Serum HDL-cholesterol was measured. Serum LDL-cholesterol and atherogenic index were calculated. Weight gain and food efficiency ratio were higher in ovx groups than in sham groups (p<0.05). Caffeine intake did not affect weight gain and food efficiency ratio. Mean food intake was significantly increased in ovx-caffeine group than other three groups. There were no significant differences in serum triglyceride, total cholesterol, HDL-cholesterol, LDL-cholesterol and atherogenic index between the control diet group and caffeine diet group. In addition, hepatic triglyceride and cholesterol level was unaffected by caffeine intake or ovariectomy. Therefore, we suggest that caffeine (0.03%/diet) intake may not have adverse effects on serum lipid level in ovariectomized rats.

• Journal of Pharmacopuncture
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• v.7 no.1 s.12
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• pp.87-100
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• 2004

Objective : This research was performed to investigate the effect of herbal acupuncture(Atratylodes japonica, Coix lachrymajobi, Ephedra sinica, Atratylodes japonica mixed with Coix lachrymajobi and Ephedra sinica mixed with Green tea) at Pungnyung(ST40) and Umnungchon(SP9) on weight gain, food intake, food efficiency, serum of lipid concentrations, liver function and HDL to total cholesterol ratio of rats fed high fat diet for 5weeks. Method : Experimental groups were divided into normal group(Normal), high fat diet group(Control), high fat diet and Atractylodes japonica-herbal acupuncture group(AJ), high fat diet and Coix lachrymajobi-herbal acupuncture group(CL), high fat diet and Ephedra sinica-herbaI acupuncture group(ES), high fat diet and Atractylodes japonica+Coix lachrymajobi-herbal acupuncture group(AJ+CL), Ephedra sinica+Green tea-herbal acupuncture group(ES+GT). Herbal acupuncture was bilaterally treated at the level of 132.5mg/kg body weight per 2day. Results : Body weight and food efficiency were decreased in AJ, ES, AJ+CL, ES+GT. The level of serum total cholesterol, triglyceride and free fatty acid were increased in AJ, ES, ES+GT. That of serum HDL-cholesterol was increased in AJ. The change of food intake, the level of serum phospholipid and ALP were not significant. The HDL to Total cholesterol ratio was increased in AJ and ES. Conclusion : Atractylodes japonica-herbal acupuncture in ST40 SP9 is effective on Body weight, food efficiency ratio, the level of serum lipid, protection of liver function and prevention cardiovascular risk by obesity induced by high fat diet. Herbal acupuncture mixed Ephedra sinica with Green tea can control the body weight, food efficiency ratio and the level of serum lipid.