• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.3
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• pp.154-159
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• 2006

It is essential to understand the decomposition characteristics for developing the optimum anaerobic digestion system of organic wastes. In this study, BMP (Biochemical Methane Potential) test using serum bottle was conducted to evaluate the anaerobic degradability of fish offal. 3 different groups of fish offal including waste from mackerel and hairtail handling except viscera and fish viscera were chosen for the substrates. Grinded fish offal was transferred anaerobically to serum bottle in amounts of 50 ml, 100 ml and 150 ml, respectively. BMP test was carried out in triplicate. Cumulative methane production and methane production rate depending on incubation time were evaluated. These results varied depending on substrate characteristics. The average values of ultimate methane yield ranged between $420ml{\cdot}CH_4/g{\cdot}VS$ and $490ml{\cdot}CH_4/g{\cdot}VS$, and the methane production and degradation rate of viscera were higher than those of other parts of fish offal. According to the analysis of elemental composition, average C/N ratio of fish offal used in this study was 5.2. Theoretical ultimate methane yield calculated from elemental composition was $522ml{\cdot}CH_4/g{\cdot}VS$. Biodegradability was calculated as 0.847.

• Korean Journal of Environmental Agriculture
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• v.36 no.1
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• pp.29-35
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• 2017

BACKGROUND: This study was carried out to assess a biochemical methane potential of giant miscanthus (Miscanthus sacchariflorus) which was a promising candidate energy crop due to a high biomass productivity, in order to utilize as a feedstock for the biogas production. METHODSANDRESULTS: Giant miscanthus was sampled the elapsing drying time of 6 months after harvesting. TS (Total Solid) and VS (Volatile Solid) contents were 94.7 and 90.8%. And CP (Crude Protein), EE (Ether Extracts), and CF (Crude Fiber) contents of giant miscanthus were 1.4, 0.46, and 46.12%, respectively. In the organic composition of giant miscanthus, the NDF (Neutral Detergent Fiber) representing cellulose, lignin, and hemicellulose contents showed 86.88%, and the ADF (Acid Detergent Fiber) representing cellulose and lignin contents was 62.91%. Elemental composition of giant miscanthus showed 47.75%, 6.44%, 41.00%, and 0.28% for C, H, O, and N, respectively, and then, theoretical methane potential was obtained to $0.502Nm^3kg^{-1}-VS_{added}$. Biochemical methane potential was assessed as the range of $0.154{\sim}0.241Nm^3kg^{-1}-VS_{added}$ resulting the lower organic biodegradability of 30.7~48.0%. CONCLUSION: Therefore the development of pretreatment technology of the giant miscanthus was needed for the improvement of anaerobic digestability.

• Nutritional Sciences
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• v.9 no.3
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• pp.190-194
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• 2006

Silajit is a blackish brown pitch-like gummy substance. It is an important Unani and Ayurvedic medicine widely used in the treatment of many diseases and as nutritional supplement It is found in certain mountainous regions of Pakistan, Afghanistan, India, Nepal, Australia and Russia. Silajit samples of Pakistani origin were obtained from different sources and analyzed for their physical characteristics and biochemical & elemental composition. X-ray diffraction studies on Silajit showed that it is an amorphous substance and has no crystalline structure. Also, pH studies of Silajit (2 g/L of water) indicated that it was slightly acidic in nature and ranged from 3.45 to 7.23. Conductivity ranged from 157.7 to 330. Amino acid analysis revealed that Silajit contained lysine and alanine in higher amounts than all other amino acids and ranged from 1456 to 2240 and 68 to $1615{\eta}mole/g$, respectively. Mean concentration of arsenic, mercury, cadmium, lead, copper and zinc was 73.15, 104.92, 0.496, 3.89, 4.04 and 17.23 ppm, respectively. Silajit samples were also analyzed for calcium, potassium and sodium.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.340-347
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• 2001

Seasonal variation of the elemental and biochemical composition of the suspended particulate matter (SPM) was investigated in terms of quantity and quality of diets for suspension feeders from July 1999 to August 2000 in two coastal bay systems of Gosung and Kangjin Bays in Korea. No clear patterns in the seasonal variations of SPM concentration were found in these two bay systems. The results indicated that the seasonal variation of SPM could not be considered the variation of food available to suspension-feeders. The simultaneous peaks in chlorophyll a and biochemical components in summer indicated that the quantity of the particulate organic matter primarily depended on phytoplankton productivity. However, no correlation between chlorophyll a and biochemical components [particulate protein (PPr), carbohydrate (PCHO) and lipid] were found, indicating that other processes might also contribute to the particulate organic matter in the period when the phytoplankton biomass was low. High C: Chl a and C:N, and carbohydrate peaks during the autumn to spring period suggested that resuspension of surface sediments was a probable process to supply the particulate organic matter. The food material, represented by summing up the total quantity of three biochemical components, was highest in spring with minor peaks during the period from autumn to the next spring, The food index, calculated as the ratio of food material to total SPM, did not generally exceed $6\%$ with short peaks during the year. Therefore, nutritional quality of SPM in the bays are relatively poor than in other more productive coastal waters in the world. Our results confirm that the measurement of a single chemical variable cannot describe fully the nutritive value of the seston available to suspension-feeders as previously proposed, and the biochemical composition of SPM can provide effective information on its origin and nutritive Quality.

• Journal of Marine Bioscience and Biotechnology
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• v.9 no.2
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• pp.22-29
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• 2017

A unicellular green alga was axenically isolated from the Port of Jeongja, Ulsan, Korea. Morphological, molecular, and biochemical analyses revealed that the isolate belonged to Heterochlorella luteoviridis. This is the first report of this species in Korea. The microalgal strain was named as H. luteoviridis MM0014 and its growth, lipid composition, and biomass properties were investigated. The strain thrived over a wide range of temperatures ($5-30^{\circ}C$) and withstood up to 0.5 M NaCl. The results of gas chromatography/mass spectrometry analysis showed that the isolate was rich in nutritionally important polyunsaturated fatty acids. Its major fatty acids were linoleic acid (35.6%) and ${\alpha}$-linolenic acid (16.2%). Thus, this indigenous marine microalga is a potential alternative source of ${\omega}3$ and ${\omega}6$ polyunsaturated fatty acids, which are currently obtained from fish and plant oils. Ultimate analysis indicated that the gross calorific value was $19.7MJ\;kg^{-1}$. In addition, the biomass may serve as an excellent animal feed because of its high protein content (51.5%). Therefore, H. luteoviridis MM0014 shows promise for applications in the production of microalgae-based biochemicals and biomass feedstock.

• Clean Technology
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• v.25 no.3
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• pp.223-230
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• 2019

This research was performed to evaluate the characteristics of food waste from 5 areas in Gangwon Province, Korea and to predict the $CH_4$ gas production rate. Food wastes were sampled in July and September, 2017. The amount of methane gas generation was evaluated through the biochemical methane potential (BMP) test and a calculation method using chemical composition. Average bulk density and pH of the food wastes were in the range of $0.758{\sim}0.850g\;cm^{-3}$ and 4.29 ~ 4.75, respectively. By physical composition, vegetables were the highest with 56.43 ~ 72.81% with fruits recording 5.31 ~ 8.95%, cereals 1.60 ~ 18.73%, fish and meat 4.47 ~ 12.11%, and filtrate 1.76 ~ 3.64%. The average water content was 69.30 ~ 75.87%, and VS and ash content were 22.50 ~ 27.98% and 1.63 ~ 2.48%, respectively. In addition, $BOD_5$, $COD_{Cr}$, and $COD_{Mn}$ were in the ranges of $17,690.3{\sim}33,154.9mg\;L^{-1}$, $106,212.3{\sim}128,695.5mg\;L^{-1}$, and $51,266.1{\sim}63,426.3mg\;L^{-1}$, respectively. The NaCl content ranged from 0.81 to 1.17%. The results of elemental analysis showed that the contents of C, H, O, N, and S were 44.87 ~ 48.1%, 7.12 ~ 7.57%, 40.13 ~ 43.78%, 3.22 ~ 4.14%, and 0.00 ~ 0.02%, respectively. In a comparison of the methane production yield per VS mass of food waste, there was no significant difference between the cumulative amount (${0.303{\sim}0.354m_{CH4}}^3\;{kg_{VS}}^{-1}$) by the BMP test and the theoretical amount (${0.294{\sim}0.352m_{CH4}}^3\;{kg_{VS}}^{-1}$) calculated by chemical composition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.57-69
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• 2001

The chemical, elemental and biochemical components of the suspended particulate matter (SPM) were investigated in order to quantify particulate organic matter (POM) and assess diet quality for suspension feeders in the southern coastal bay systems of Korea where the marine farming of the suspension feeders are most active, The intense field observation program was carried out seasonally in the three coastal bay systems of Chinhae, Gosung and Kangjin bays, The SPM was characterized as collective properties of organic carbon (POC), nitrogen (PON), phosphorus (PP) and more refined collective properties of protein (PPr), carbohydrate (PCHO) and chlorophyll a (Chl a) compound. Although the three coastal bays are regarded as phytoplankton based ecosystem, the SPM is not composed entirely with phytoplankton cells. Due to the shallow water depth, resuspension of bottom sediment contributes significantly to some of the regions. Therefore, concentration of SPM in the surface water did not co-vary with Chl a or PPr, PCHO. In general, temporal variation of POC, PON and Chl a contents in seawater were closely associated with phytoplankton biomass in the three coastal bays, However, PPr and PCHO contents in seawater were higher in Chinhae bay than in Gosung and Kangjin bays and Chl a PPr-N ratio was higher in Chinhae bay than in Kosung and Kangjin bays, since Chinhae bay is more eutrophicated than other bays. Average C : N ratios from regressions of POC and PON of SPM were 6.6, 6.6 and 5.0 in Chinhae, Gosung and Kangjin bays, respectively. SPM in Chinhae and Gosung bays appears to be made of largely phytoplankton cells and SPM in Kangjin bay appears to be contributed from the bacterial biomass due to the shallow water depth. N : P ratios from regressions of PON and PP of SPM were 10.8 and 14.7 in spring, and 18.2 and 24.6 in Chinhae and Gosung bays, respectively. With respect to the hypothetical Redfield molecule, phytoplankton appears to be limited by the lack of N and f in spring and summer, respectively, in the two bays, In Kangjin bay, N : P ratios from regressions of PON and PP of SPM were varied from 6.3 to 12.8 throughout the year. The low N : P ratio with resepct to the hypothetical Redfield molecule, phytoplankton growth appears to be limited by the lack of N-nutrients.