• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.487-496
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• 2021

Microalgae is one of the promising biodiesel feedstock with high growth rates compared to those of terrestrial oil crops. Despite its numerous advantages, biodiesel production from microalgae needs to reduce energy demand and material costs further to go to commercialization. During solvent extraction of microalgal lipids, lipid-extracted algae (LEA) cell residue is generated as an organic solid waste, about 80-85% of original algal biomass, and requires an appropriate recycling or economic disposal. The resulting LEA still contains significant amount of carbohydrates, proteins, N, P, and other micronutrients. This review will focus on recent advancement in the utilization of LEA as: (i) utilization as nutrients or carbon sources for microalgae and other organisms, (ii) anaerobic digestion to produce biogas or co-fermentation to produce CH₄ and H₂, and (iii) conversion to other forms of biofuel through thermochemical degradation processes. Possible mutual benefits in the integration of microalgae cultivation-biodiesel production-resulting LEA with anaerobic digestion and thermochemical conversion are also discussed.

• Environmental Engineering Research
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• v.24 no.2
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• pp.202-210
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• 2019

In order to maximize the utilization of sewage sludge, a waste from wastewater treatment facility, the residual sewage sludge generated after lipid and carbohydrate extraction for biodiesel and bioethanol production was used to produce bio-oil by pyrolysis. Thermogravimetric analysis showed that sludge pyrolysis mainly occurred between 200 and $550^{\circ}C$ (with peaks formed around 337.0 and $379.3^{\circ}C$) with the decomposition of the main components (carbohydrate, lipid, and protein). Bio-oil was produced using a micro-tubing reactor, and its yield (wt%, g-bio-oil/g-residual sewage sludge) increased with an increase in the reaction temperature and time. The maximum bio-oil yield of 33.3% was obtained after pyrolysis at $390^{\circ}C$ for 5 min, where the largest amount of energy was introduced into the reactor to break the bonds of organic compounds in the sludge. The main components of bio-oil were found to be trans-2-pentenoic acid and 2-methyl-2-pentenoic acid with the highest selectivity of 28.4% and 12.3%, respectively. The kinetic rate constants indicated that the predominant reaction pathway was sewage sludge to bio-oil ($0.1054min^{-1}$), and subsequently to gas ($0.0541min^{-1}$), rather than the direct conversion of sewage sludge to gas ($0.0318min^{-1}$).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.195-201
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• 1998

Anchor Engraulis japonica was fermented with $10\%$ and $20\%$ salt at $10^{\circ}C$ ($10\%$ 5A) and $20^{\circ}C$ ($20\%$ SA), respectively, and the changes in lipid content, fatty acid composition and lipid oxidation was observed for 105 days. Peroxide value (POV) in $10\%$ SA reached to the maximum (46.4 meq/kg) on 30 days of fermentation, while in $20\%$ SA, it reached the maximum (54.7 meq/kg) on 45 days of fermentation, and then decreased in both samples during fermentation. Thiobarbituric acid values revealed a similar tendency with the change of POV during the fermentation. These results indicated that lipid of the anchovy was oxidized faster in lower salt than high salt in the early stage. Total lipid (TL) content during the fermentation for 105 days decreased approximately $16\%$ in $10\%$ SA and approximately $33\%$ in $20\%$ SA. Phospholipid (PL) content also decreased in both samples and the content of neutral lipid (NL) was unchanged in $10\%$ SA, while it decreased in the same amount as PL in $20\%$ SA. The prominent fatty acids in TL of the anchovy sample were 14 : 0, 16 : 0, 16 : In-7, 18 : in-9, 20 5n-3 and 22 : 6n-3. After fermentation for 105 days, approximately $87\%$ and $67\%$ of the prominent fatty acids remained in $10\%$ SA and $20\%$ SA, respectively, but the kind of the fatty acids was unchanged.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.156-163
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• 2001

Vanadium has been known as environmental polluants resulted from the burning of fossil fuels in nature. It led to toxic responses by prooxidant activity, inducing free radicals and the accumulation in the tissues. Recently, there has been growing interest in an essential nutritional requirement of vandium and especially the treatment of diabetes. But because of its strong toxicity, thease chemicals have narrow safety margin. In order to reduce metal toxicity, and increase absorption and biological activities, metal ions such as selenium and chromium were uptaken in yeast cells. In this study, Vanadium yeast was prepared by uptaking vanadate in yeast cells. Vanadate induced hematological and biochemical changes in the experimental rat blood were inhibited by the treatments of vanadium yeast. Lipid peroxidation and catalase activity were significantly increased in kidney and liver after a single intraperitoneal injection of vanadate to rats. However, these observations were apparently reduced in the vanadium yeast treated group. Vanadium amount in blood, kidney and liver after a single intraperitoneal injection of vanadium yeast was significantly reduced than that of vanadate treated group. In conclusion, vanadium yeast uptaken vanadate in yeast cells could reduce toxic effects of vanadate.

• Environmental Engineering Research
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• v.21 no.4
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• pp.401-408
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• 2016

The aim of this study was to evaluate the biomass and lipid production of Chlorella vulgaris and its nutrient removal capability for treatment of brewery wastewater effluent. The results indicate that the maximum biochemical oxygen demand (BOD) (91.43%) and chemical oxygen demand (COD) (83.11%) were removed by C. vulgaris with aeration in the absence of light. A maximum of 0.917 g/L of dry biomass was obtained with aeration in the dark conditions, which also demonstrated the highest amount of unsaturated fatty acids at 83.22%. However, the removal of total nitrogen (TN) and total phosphorus (TP) with these aeration and light conditions was 9.7% and 11.86% greater than that of other conditions. The removal of BOD and COD and the production of biomass and lipids with aeration in the dark and the TN and TP removal with aeration and light were more effective than other conditions in the brewery wastewater effluent in the presence of C. vulgaris.

• Journal of Nutrition and Health
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• v.20 no.6
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• pp.422-431
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• 1987

Dietary habits and serum lipid composition of 80 hospitalized patients with cerebrovascular disease (CVD) were compared to those of normal subjects. CVD patients were significantly higher in BP, serum cholesterol and triglyceride levels and low4r in HDL-choelsterol which resulted in the higher ratio of serum chol/HDL-chol than normal. Patients were also lower in the relative amount of HDL fraction by electrophoresis but were higher in LDL fraction and the ratio of LDL/HDL . In Korean, the high levels of serum chol, TG and LDL with low level of HDL as well as high BP could be one of the important causing factors of CVD. However, dietary habits of patients were not significantly different from those of normal . There is a possibility that patients might have controlled their dietary habits after they realized the severeness of disease.

• Journal of Nutrition and Health
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• v.19 no.5
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• pp.289-295
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• 1986

Seven day's menus consisting of the Korean traditional dietary patterns were prepared according to the Korean nutrition allowances per capital of whole population. After cooking foods one day's meal was collected, homogenized for one week. Nutrients in each day's meal were analysed. The results of this analysis are as follows ; Lipids contents were about 23% higher than the data obtained nationwide nutrition survey conducted in 1984. This suggests the increasing tendency of the fat the oil consumption . PUFA ratio in lipid was 35%, that the customary Korean cooking include high confirmiry amount of vegetable oils. Daily tocopherol intake was 8.3mg . This results is believed to as one reference to set up Korean R.D.A for tocopherol.

• The Korean Journal of Pharmacology
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• v.5 no.1
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• pp.1-9
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• 1969

Alkaloidal fraction, a principle of ginseng extract was administered to rats orally in the amount of 2.5 mg per day per 100 gm body weight continuously for eight weeks to assess the lipid content of the serum and liver tissue. The findings can be summarized as follows: 1. Total cholesterol contents of serum and liver tissue were found to decrease with the administration of ginseng alkaloidal fraction. 2. Phospholipid contents increased in the serum and decreased in the liver tissue with the administration of ginseng alkaloidal fraction. 3. Triglyceride contents of the serum as well as liver tissue increased with the administration of ginseng alkaloidal fraction during the first 4 weeks but decreased in the second 4 weeks to reach a level below that of the pre-experimental period.

• Preventive Nutrition and Food Science
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• v.5 no.1
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• pp.7-9
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• 2000

Variouss concentrationss of free malonaldehyde were prepared from 1,1,3,3-tetraethoxy propane (TEP). Spectrophoto-metric determination and HPLC analysis of free malonaldehyde instead of malonaldehyde-thiobaribituric acid (MA-TBA) complex were conducted. Malonaldehyde was well separated on a $\mu$Bondapak C18 column. The absorbances at 254 nm and the HPLC peak areas of free malonaldehyde increased with the increase in its concentration. The correlation coefficient between absorbances and peak areas was 0.998. The total time elapsed to conduct the whole procedure was less than 15 minutes. This method directly measured the amount of free malonaldehyde in a short period of time successfully. This procedure is expected to be used as a rapid, accurate and specific means to de-termine the development of lipid oxidation in food.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.1
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• pp.51-58
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• 1996

The effects of allylisothiocyanate on the biosynthesis of various fungus metabolites such as sterigmatocystin, lipid, protein, citrate RNA and AMP from the culture of Aspergillus Parasiticus R-716 were investigated. The content of sterigmatocystin, the precursor of aflatoxin, was lower in the culture added with 50ppm allylisothicoyanate after 48 hours, however was rather higher after 144 hours compared to that of the control. The addition of allylisothiocyanate resulted in the increase of lipid, protein, RNA in mycelium and the content of citrate in the media, but the amount of AMP was low.