• Korean Journal of Environmental Agriculture
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• v.7 no.2
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• pp.87-91
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• 1988

To investigate the effects of paper sludge on the seasonal variations of higher fatty acids in paddy soil, paper sludge was applied to pots at the rate of either 300, 600, 900 or 1,200kg/10a. Fractions of the higher fatty acids in the soil were analyzed. 1. Twenty-one kinds of higher fatty acids in the soil were detected. Among them, lauric, myristic, myristoric, palmitic, palmitoleic, stearic, oleic, linoleic, linolenic and arachidic acids were identified. The fatty acid content in the soil of acids, linolonic, myristic, palmitic, and stearic acid increased in ascending order. 2. The total content of higher fatty acids in the soil was increased as the application of paper sludge increased. The formation of the acids was at its highest point at the effective tillering stage. After WARDS the contents of the acids decreased as time elapsed. A positive correlation was observed between the total contents of both higher and volatile lower fatty acids in the soil.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.526-529
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• 1990

Free fatty acids of two brands of domestic butter were isolated directly by a modified silicic acid column chromatography, and were analyzed by gas liquid chromatography. $C_{18}$ FFA congeners $(C_{18_0},\;C_{18:1},\;C_{18:2}\;and\;C_{18:3})$ were the predominant components (52.83% in brand A and 47.50% in brand B), followed by $C_{16}$FFA (29.39% in brand A and 30.52% in brand B) and $C_{14}$FFA (11.85% in brand A and 13.76% in brand B). The other FFA were present as minor components (0.29-3.87%). Concentrations of four FFA $(C_4,\;C_6,\;C_{10}\;and\;C_{12})$FFA which would be expected to contribute strongly to hydrolytic rancidity off-flavors were below individual threshold level, except $C_4FFA$ (56 ppm) in butter B.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.8
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• pp.652-660
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• 2003

T-history method, measuring heat-of-fusion of phase change material (PCM) in sealed tubes, has the advantages of a simple experimental device and no requirements in sampling process. However, a degree of supercooling used in selecting the range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion in the original method, which has been improved in order to predict better results by us. In the present study, the modified method was applied to a variety of PCM such as paraffin and lauric acid having very small or no supercooling with a satisfactory precision. Also the selection of inflection point and temperature measurement position was fumed out not to affect the accuracy of heat-of-fusion significantly. As a result, the method can provide an appropriate means to assess a new developed PCM by cycle test even if a very accurate value cannot be obtained.

• Journal of the Korean Chemical Society
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• v.65 no.2
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• pp.145-150
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• 2021

The present study describes a hands-on experiment to help students understand the concept of phase change or phase transition and its application in a phase change material (PCM). PCMs are substances that have the capability of storing and releasing large amounts of thermal energy. They act as energy storage materials that provide an effective way to save energy by reducing the electricity required for heating and cooling. Lauric acid (LA) was selected as an example of the PCM. Students investigated the temperature change of LA and the temperature (of air) inside the test tube. The differences in the temperatures of the systems helped students understand how PCMs work. A one-group pretest and posttest design was implemented with 34 grade-11 students in science and mathematics. Students' understanding was assessed using a multiple-choice test and a questionnaire. The findings revealed that the designed activity helped students understand the concept of phase change and its application to materials for thermal energy storage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.65-66
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• 2023

This study is aimed to understand the effect of pyrolysis temperature on the biochar synthesis for shape stabilizing the Lauric acid (LA). Three different temperatures (350, 500, and 650 ℃) have been chosen with a soaking time of 1h for synthesizing biochars form sesame plants (SP). The structural characterizations indicate the formation of amorphous biochar at 350 ℃ whereas, a stain of graphene formation has been observed for the biochar synthesized at 500 ℃. Formation of a substantial amount of graphene has been found for the sample, synthesized at 650 ℃. Energy storage performances of the PCMs which are shape stabilized by these three biochars have been discussed in this paper.

• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.294-301
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• 1997

Fatty acid, amino acid and organic acid contents were analyzed by gas chromatography, amino acid analyzer and high pressure liquid chromatography, respectively, in order to compare the chemical constituents of upland wasabi plant propagated by seed and auxiliary bud. Total fatty acid content and fatty acid composition of upland wasabi were not affected by the propagation methods. Generally, fatty acid content of leaf was higher than that of other parts such as enlarged stem, petiole, peduncle and root. In fatty acid composition, leaf had highest content of linolenic acid, 60-63%, in plant propagated by both seed and auxiliary bud, followed by palmitic acid, oleic acid and linoleic acid in the order. Similarly, total amino acid content was not influenced by propagation methods but plant propagated by seed had higher amount of amino acid content in enlarged stem, petiole and root than that by auxiliary bud -propagated plant. A total of 17 amino acids including 7 essential amino acids were identified in both seed and auxiliary bud propagations. Like total fatty acid content and fatty acid composition, leaf contained high amount of amino acids, especially glutamic acid, asparatic acid and leucine. Organic acid contents were similar in both propagation methods. The major organic acid in upland wasabi was acetic acid (60.0-78.2%), followed by succinic acid (9.9-29.7%) and malic acid (2.9-7.9%). Maleic acid content was least (0.5-2.6%). The result indicates that content and composition of fatty acid, amino acid, and organic acid in upland wasabi were not influenced by propagation methods.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.391-399
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• 2011

Free fatty acids (FFAs) are known to have bacteriocidal activity and are important components of the innate immune system. Many FFAs are naturally present in human and animal skin, breast milk, and in the bloodstream. Here, the therapeutic potential of FFAs against methicillin-resistant Staphylococcus aureus (MRSA) is demonstrated in cultures and in mice. Among a series of FFAs, only oleic acid (OA) (C18:1, cis-9) can effectively eliminate Staphylococcus aureus (S. aureus) through cell wall disruption. Lauric acid (LA, C12:0) and palmitic acid (PA, C16:0) do not have this ability. OA can inhibit growth of a number of Gram-positive bacteria, including hospital and community-associated MRSA at a dose that did not show any toxicity to human sebocytes. The bacteriocidal activities of FFAs were also demonstrated in vivo through injection of OA into mouse skin lesions previously infected with a strain of MRSA. In conclusion, our results suggest a promising therapeutic approach against MRSA through boosting the bacteriocidal activities of native FFAs, which may have been co-evolved during the interactions between microbes and their hosts.

• CELLMED
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• v.6 no.2
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• pp.11.1-11.7
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• 2016

The aimed of the presence study was to determine the antiulcer potential of virgin coconut oil (VCO), either extracted by wet process (VCO_A) or fermentation process (VCO_B), and to compare their effectiveness against the copra oil (CO) using the HCl/ethanol-induced gastric ulcer model. Earlier, the oils underwent chemical analysis to determine the free fatty acids composition, physicochemical properties and anti-oxidant capability. In the antiulcer study, rats (n=6) were pre-treated orally for 7 consecutive days with distilled water (vehicle), 100 mg/kg ranitidine (positive group) or the respective oils (10, 50, and 100% concentration). One hour after the last test solutions administration on Day 7^th, the animals were subjected to the gastric ulcer assay. Macroscopic and microscopic analyses were performed on the collected rat's stomachs. From the results obtained, the chemical analysis revealed i) the presence of high content of lauric acid followed by myristic acid and palmitic acid in all oils and; ii) the significant (^*p< 0.05) different in anisidine- and peroxide-value, percentage of free fatty acid, total phenolic content and total antioxidant activity among the oils. The animal study demonstrated that all oil possess significant (^*p< 0.05) antiulcer activity with VCO_B being the most effective oil followed by VCO_A and CO. The macroscopic observations were supported by the microscopic findings. Interestingly, all oils were more effective than 100 mg/kg ranitidine (reference drug). In conclusion, coconut oils exert remarkable antiulcer activity depending on their methods of extraction, possibly via the modulation of its antioxidant and anti-inflammatory activity.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.249-257
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• 2022

The present study investigates the effects of different inclusion levels of a microwave-dried black soldier fly (Hermetia illucens) larvae meal (HILM) on the carcass characteristics, breast meat quality, and fatty acid profiles of leg meat in broiler chickens. A total of 150 male broilers were randomly assigned to three dietary treatment groups (10 replicates·treatment^-1 and 5 birds·replicate^-1). HILM was included at increasing levels (0, 2, and 4%; CON, 2HILM, and 4HILM, respectively) in diets formulated for three feeding phases: starter (1 - 7 d), grower (7 - 21 d), and finisher (21 - 35 d). One bird per replicate was slaughtered at d 35; the carcasses and organs were weighed, and breast and leg meats were excised for a meat analysis. A linear decrease (p < 0.01) was observed for live and carcass weights for the whole period of the experiment, with no difference between the CON and 2HILM groups. Broilers fed HILM showed no significant differences in meat quality parameters, except for an increase in yellowness (b^*) in the 2HILM and 4HILM groups compared to the CON group (p < 0.01). With an increase in the HILM inclusion level, the proportion of saturated fatty acids (SFAs) such as lauric, myristic, stearic, arachidic, and heneicosylic acids showed a linear increase (p < 0.01); however, total SFA, monounsaturated fatty acid, and polyunsaturated fatty acid did not differ among the dietary treatments. Thus, microwave-dried HILM can be considered as a possible alternative ingredient to soybean meal in broiler diets up to a 2% inclusion level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.406-412
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• 1984

Total lipids (TL) from Korean pinenut (Pinuskoraiensis S & Z) were extracted, purified and fractionated into three lipid classes (neutral lipid: NL, glycolipid; GL, phospholipid; PL). Lipid contents(constituent components) and fatty acid composition of three lipid classes were determined by thin layer chromatography and gas chromatography. TL ranged from 69.0% to 69.8% in fresh pinenut and consisted of 95.9% to 96.7% NL, 3.2% to2.5% GL and 0.9% to 0.8% PL. In the NL, triglycerides were predominant (80.8%) with the smaller amounts of sterol, diglycerides, free fatty acids, sterol esters and hydrocarbons. Monogalactosyl diglycerides and esterified steryl glycosides (23.5%) were the major components of GL, but cerebrosides, steryl glycosides and digalactosyl diglycerides were also found as minor components. Of the PL, phosphatidyl choline (40.2%) and phosphatidyl ethanolamine (19.4%) were the major components, comprising over 60% of this class. Phosphatidyl inositol, lysophosphatidyl choline were also present in the PL. The major fatty acids in the NL were linoleic acid (48.6%), oleic acid (28.8%) and arachidic acid(14.4%), The fatty acid composition in the GL was similar to the pattern in the NL, but PL contained a higher percentage of palmitic acid (17.7%) and stearic acid (6.0%) than other lipid classes.