• Applied Biological Chemistry
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• v.41 no.1
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• pp.67-72
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• 1998

As a part of basic investigation for utilizing by-products derived from seafood processing as a food source, a chemical characteristics of fish bones (cod bone, Alaska pollack bone, yellowfin sole bone, hoki bone, conger eel bone and mackerel bone) were investigated. The crude protein (40.7% on the dry basis) and collagen contents (5.86%, on the dry basis), imino acid composition (189 residues/1,000 residues) of hoki bone were higher than those of the other fish bones, but were lower than those of the animal bone. The crude lipid contents and EPA and DHA compositions of yellowfin sole, conger eel and mackerel bones were $22.8{\sim}43.9%$ on the dry basis and $15.6{\sim}23.8%$, respectively and were lower than those of squid viscera. The major ash components of the fish bones were found to be calcium and phosphorus and the contents in 100 g crude ash were $37.1{\sim}38.6%$ and $18.0{\sim}18.5%$ respectively. The calcium and phosphorus contents in 100 g crude ash of cod and Alaska pollack bones were more than those of the animal bones, as well as the others. It may be concluded, front these results, hoki bone can be effectively utilized as a processing materal of collagen or gelatin and cod and Alaska pollack bones as a calcium source.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.140-145
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• 2002

The performances of a parallel current air driven type foam separator were evaluated in the pilot-scale recirculating aquaculture system. The system was stocked with Nile tilapia (Oreochromis niloticus) at an initial rearing densities of $2\%$, $5\%$ and $7\%$ of water volume of rearing tank and reared for 15, 30, 35 days, respectively. The condensated volume of effluent foam was increasing with increased rearing density. As increasing rearing density from $2\%$ to $7\%$, the protein concentration in rearing tank was increased from 16.6 g/$m^3$ to 21,9 g/$m^3$ and the removal amount of protein through foam separator as increased from 0.99 g/day to 2.5 g/day. But protein concentration ratio in the foam was decreased from 3.2 to 1.9. Changes of the removal amount and the concentration ratios of total suspended solid (TSS) and chemical oxygen demand (COD_cr.) were similar to proteins. The highest concentration ratios of TSS and COD_cr. were 10.2 and 8.4 at 2$2\%$ of rearing density.

• Membrane and Water Treatment
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• v.6 no.6
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• pp.501-512
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• 2015

A laboratory-scale submerged membrane bioreactor (MBR) was continuously operated for 100 d at an infinite sludge retention time (SRT) with the aim of identifying possible relation between the filterability of mixed liquor and sludge properties, such as extracellular polymeric substances (EPS), soluble microbial products (SMP), viscosity of mixed liquor, zeta potential of flocs and particle size distributions (PSD). Research results confirmed that MBR can operate with a complete sludge retention ensuring good treatment performances for COD and $NH_3-N$. However, the long term operation (about 40 d) of MBR with no sludge discharge had a negative influence on sludge filterability, and an increase in membrane fouling rates with the time was observed. There as a strong correlation between the sludge filterability and the fouling rate. Among the different sludge properties parameters, the concentration SMP and EPS had a more closely correlation with the sludge filterability. The concentrations of SMP, especially SMP with MW above 10 kDa, had a strong direct correlation to the filterability of mixed sludge. The protein fractions in EPS were biodegradable and available for microorganism metabolism after about 60 days, and the carbohydrates in EPS had a significantly negative effect on sludge filterability in MBR at an infinite SRT.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.2
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• pp.43-50
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• 2021

Growth tests on the Yuldo, Supum1 and Supum2 cultivars of Pyropia dentata were performed at the Eoran and Imha aquafarm, Haenam in Jeollanamdo, from October to December in 2017. The mean water temperature ranged from 5.4 to 26.4 ℃. In Eoran aquafarm (flating raft method), dissolved total nitrogen (DTN), dissolved total phosphorus (DTP), total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD) ranged from 0.091 to 0.181 mg/L, 0.007 to 0.019 mg/L, 0.114 to 0.187 mg/L, 0.008 to 0.033 mg/L and 0.200 to1.000 mg/L, respectively. In Imha aquafarm (fixed pold method), DTN, DTP, TN, TP and COD ranged from 0.118 to 0.276 mg/L, 0.005 to 0.024 mg/L, 0.155 to 0.305 mg/L, 0.009 to 0.042 mg/L and 0.300 to1.400 mg/L, respectively. In order to investigate the number of conchospores attached on the Pyropia net, which was cut into about 4cm long. The mean number of conchospores of Yuldo, Supum1 and Supum2 cultivars were 39.5, 26.5, 72.5, respectively. Young thalli were harvested two times at Eoran aquafarm, and three times at Imha aquafarm. In eoran aquafarm, the mean thallus length of Yuldo, Supum1 and Supum2 cultivars were 49.9, 46.0, 42.0 cm on October and 163, 126.0, 263.0 cm on November, respectively. The mean thallus width of Yuldo, Supum1 and Supum2 cultivars were 5.8, 4.6, 11.5 cm on October and 20.9, 11.5, 14.0 cm on November, respectively. In Imha aquafarm, the mean thallus length of Yuldo, Supum1 and Supum2 cultivars were 119.0, 60.9, 71.0 cm on October, 196.0, 132.0, 262.0 cm on November and 187.0, 281.0, 296.0 cm on December, respectively. The mean thallus width of Yuldo, Supum1 and Supum2 cultivars were 4.2, 3.4, 3.1 cm on October, 8.9, 6.2, 6.6 cm on November and 11.7, 11.6, 9.4 cm on December, respectively. In eoran aquafarm, contents of moisture, crude ash, crude lipid, crude protein and carbohydrate of three cultivars ranged from 11.64 to 20.15, 19.54 to 21.19, 0.00 to 0.18, 29.78 to 37.81, 29.16 to 29.71, respectively. In Imha aquafarm, contents of moisture, crude ash, crude lipid, crude protein and carbohydrate of three cultivars ranged from 8.43 to 9.15, 11.42 to 17.49, 0.00 to 0.00, 31.90 to 37.54, 36.30 to 42.24, respectively.

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.147-153
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• 2010

A study was carried out to examine the effect of water temperature on daily pattern and rate of total ammonia nitrogen (TAN) excretion in juvenile Pacific cod Gadus macrocephalus (mean body weight: $36.5{\pm}0.8\;g$) under fasting and feeding conditions. Fish were acclimated over 10 days under three different water temperatures (9, 11 and $13^{\circ}C$), and transferred to TAN measuring system under each water-temperature condition. After 72 hours of starving, fasting TAN excretion was measured at each temperature. To investigate post-prandial TAN excretion, fish were hand-fed with a commercial diet containing 40.6% crude protein for 7 days, two times daily at 08:00 and 16:00 h. Water was sampled from both the inlet and outlet of the fish chamber every 2 h over a 24-h period. Both fasting and post-prandial TAN excretion increased with increased water temperatures (p<0.05). Mean fasting TAN excretion rates at 9, 11 and $13^{\circ}C$ were 9.3, 11.0 and $11.9\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$, respectively. The value of $9^{\circ}C$ was lower than those of 11 and $13^{\circ}C$ (p<0.05), but there was no significant difference between $11^{\circ}C$ and $13^{\circ}C$. Mean post-prandial TAN excretion rates at 9, 11 and $13^{\circ}C$ were 23.0, 31.6 and $45.4\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$, respectively. A peak value of post-prandial TAN excretion rate occurred after 2 h from each feeding, and the second value is always higher than the first value. Maximum post-prandial TAN excretion rate occurred after 10 h from the first feeding at $9^{\circ}C$ (mean $38.0\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$), $11^{\circ}C$ ($52.9\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$) and $13^{\circ}C$ ($77.5\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$), respectively. The TAN loss for ingested nitrogen at $9^{\circ}C$ (43.9%) was lower than those of $11^{\circ}C$ (46.4%) and $13^{\circ}C$ (48.4%). The overall results indicate that water temperature exhibits a significant effect on the nitrogen excretion of juvenile Pacific cod.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.2
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• pp.89-97
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• 2007

In this study, thermalpretreatment was used to solubilize organic matter contained in sewage sludge before acid fermentation. By thermal pretreatment, solubilization of particulate CODcr, carbohydrate and protein increased. By thermal treatment at $120^{\circ}C$ for 30 minutes, CODcr solubilization efficiency of the primary sludge reached 8.3%. Meanwhile, for the secondary sludge, CODcr solubilization efficiency reached 16.5% because of high solubilization ratio of protein under the same pretreatment conditon. The results of anaerobic biodegradability test showed that both VFAs conversion ratio and hydrolysis rate of organic compounds in sewage sludge were improved by thermal pretreatment. Meanwhile, the optimum thermal pretreatment condition was varied with composition of organic compounds in sludge. In this study, the optimun thermal pretreatment condition of the primary sludge, containing high concentration of carbohydrate, was $80^{\circ}C$ for 30 minutes. Meanwhile, for the secondary sludge, mainly composed of protein, the sludge treated at $120^{\circ}C$ for 30 minutes showed the effective organic removal and VFAs production.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.519-524
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• 1996

The kinetics of growing microalga, Spirulina platensis was investigated to treat swine wastes with optimum growth conditions. Temperature was varied from 15 to 40$\circ$C at three different light intensities, 6 W/m$^{2}$, 12 W/m$^{2}$ and 24 W/m$^{2}$. The specific growth rate was increased as temperature increased up to 30$\circ$C. The activation energy was estimated as 13.5 kcal/mol by an Arrhenius relationship. 0.24 (1/day) of specific growth rate was obtained from batch cultivation with 30% swine wastes, compared to 0.31 (1/day) from clean culture. It was found that Spirulina platensis was able to reduce 70-93% of PO$_{4}$$^{3-}$ -P, 67-93% of inorganic nitrogen, 80-90% of COD and 37-56% organic nitrogen by adding various concentrations of swine wastes for 12 days of batch cultivation. Rate constants for removing nitrates and phosphates in treating swine wastes were estimated as 0.17 (1/day) and 0.14 (1/day) in the first order reaction, respectively. 1.52 (g/L) of maximum cell density was maintained at 0.20 (1/day) of dilution rate in continuous culture, adding 20% swine wastes for 30 days. The chemical composition of the biomass obtained from the process showed 58.7% of protein, 11.0% of lipid and 15.6% of ash.

• Archives of Pharmacal Research
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• v.19 no.5
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• pp.374-380
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• 1996

Sprague-Dawley male rats (150 g) were chronically treated with 5 v/v % ethanol admixed with nutritionally complete liquid diet and fed ad libitum for 3 weeks. One half of each group was exposed to cold stress at 4 ^{\circ}C either for 24 h (for determination of mRNA by in situ hybridization) or for 48 h (for determination of enzyme activity). Chronic ethanol treatment (ethanol) did not affect tyrosine hydroxylase(TH) mRNA level in locus coeruleus(LC) of brain and adrenal medulla(AM) compared to controls. Cold stress showed strong increase of TH mRNA level in LC and AM compared to controls. Pretreated ethanol reduced the increased TH mRNA level by cold stress in LC and AM. Ethanol did not affect TH activity in LC and adenal glands(adrenals). Cold stress increased TH activity in LC but not in adrenals. Pretreated ethanol did not reduce the increased TH activity by cold stress in LC but this result was not shown in adrenals. Phenylethanolamine-N-methyltransferase(PNMT) activity in $C_{1}$$C_{2}$ and adrenals increased only in ethanol treated group. THese results suggest that ethanol does not affect TH mRNA level and activity in LC and adrenals, but increases PNMT activity in $C_{1}$$C_{2}$ and adrenals in normal rat. It is also suggested that pretreated ethanol reduces the magnitude of cold stress response, that is induction of TH mRNA in LC and AM, and does not reduce the protein activation of TH that is also cold stress response in LC.

• Advances in nano research
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• v.8 no.2
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• pp.183-190
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• 2020

The objectives of this research were the reduction of membrane fouling and improvement of sludge properties by using synthesized H-ZSM-5 and NH₄-ZSM-5 zeolites. These two nano zeolites were synthesized and added to the membrane bioreactor (MBR). Three similar MBRs with the same operational condition were used in order to evaluate their effect on the mentioned matters. The evaluated parameters were trans-membrane pressure (TMP), Fourier-transform infrared spectroscopy (FTIR), particle size distribution (PSD), soluble microbial product (SMP), extracellular polymeric substances (EPS) and, excitation-emission matrix (EEM). The MBR₀ was without any additional zeolite while 0.4 g/L of H-ZSM-5 and NH₄-ZSM-5 were added to MBR_HZSM-5 and MBR_NH4ZSM-5, respectively. The COD removal of the MBR₀, MBR_H-ZSM-5 and MBR_NH4-ZSM-5 were 87.5%, 93.3% and 94.6%, respectively. The TMP of the MBR_H-ZSM-5 was 45% less than MBR₀ whereas the reduction for MBR_NH4-ZSM-5 was 65.5%. Also results showed that both H-ZSM-5 and NH₄-ZSM-5 caused reduction in protein and polysaccharide related EPS but the NH₄-ZSM-5 had better performance toward the elimination of organic compounds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.398-404
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• 1984

This study was attempted to investigate variation of the bacterial flora in waste water treatment of fish meat paste plant by batch and continuous culture. The results of the experiment are as follows : 1. The removal rate of BOD in waste water treatment by activated sludge of continuous culture was above $90\%$. 2. In the process of nitric acidification of protein waste water, $NH_4-N\;and\;NO_2-N$ increased untill the lapse of 48 hours from culture, but $NO_3-N$ showed little change. 3. In activated sludge obtained from acclimation by batch culture for 10 days, bacteria good in capacity of nitric acidification were not appeared. 4. Among 120 strains of isolated bacteria, the most predominantly appeared bacterial flora were Enterobacteriaceae ($28\%$) and Pseudomonas spp. ($25\%$), In the latter term of aeration during which ammonia originates in abundance, Pseudomonas spp. was decreased but Enterobarteriaceae was increased. 5. Fifty percent of the isolated strains were able to grow in $0\%,\;3\%$ NaCl and $75\%$ artificial sea water, Therefore, it is suggested that sea water can be used as dilution water instead of tap water during the treatment of waste water.