• Journal of Marine Bioscience and Biotechnology
• /
• v.14 no.1
• /
• pp.1-8
• /
• 2022

This study examined the growth, fatty acid (FA) content, and carotenoids of a newly isolated freshwater microalga, Mychonastes sp. 246, in various culture media. The appropriate temperature and light intensity for culturing Mychonastes sp. 246 were determined as 18℃-22℃ and 200-250 µmol/m²/s using a high throughput photobioreactor. The microalgal cells were cultivated in 0.5 L bubble column photobioreactors using BG11, Bold's Basal media, and f/2 media. According to the growth results of the microalgae, BG11, among the tested media, showed the highest biomass concentrations (3.5 ± 0.1 g/L in 10 d). To enhance the biomass growth of the microalgae, the N:P ratio in BG11 was manipulated from 45:1 to 7:1 based on the stoichiometric cell composition. The biomass concentrations of Mychonastes sp. 246 grown on the manipulated BG11 (MBG) increased to 38% (4.6 ± 0.3 g/L in d) compared with the original BG11 (3.3 g/L). The FA content of the microalgae grown on the MBG was lower (8.4%) than that of the original BG11 (10.1%) while the FA compositions did not exhibit any significant differences. Furthermore, three kinds of carotenoids were identified in Mychonastes sp. 246, zeaxanthin, lutein, and β-carotene. These results suggest an effective strategy for increasing biomass concentrations, FA content, and carotenoids of microalgae by performing a simple N:P adjustment in the culture media.

• Journal of Aquaculture
• /
• v.21 no.4
• /
• pp.203-212
• /
• 2008

A nutritional demand of oyster, Crassostrea gigas larva as part of research for improving of utilization of microalgae being used for the artificial oyster seed production. The change of body growth and biochemical compositions of larvae were investigated during larvae rearing in hatchery. The larvae were cultured in 60 M/T tank and fed mixture 6 different phytoplankton species, Isochrysis galbana (30%), Cheatoceros gracilis (20%), Pavlova lutheri (20%), Phaeodactylum triconutum (10%), Nannochryis oculata (10%) and Tetraselmis tetrathele (10%). The initial feeding amount was $0.3{\times}10^4cells/mL$ at three times a day to D-shaped larva and the feeding amount had been increased 30% gradually every two day since the larvae were raising. The larvae were developed from D shape to pediveliger stage for 12 days. The daily growth of shell length and hight were $5.8{\sim}30.8\;{\mu}m$ and $8.7{\sim}31.4\;{\mu}m$, respectively and weight gains were changed from D shape to pediveliger as follow: wet weight was $0.52{\sim}15.0\;{\mu}g/larva$, dry weight was $0.2{\sim}6.5\;{\mu}g/larva$, and ash free dry weight was $0.1{\sim}8.5\;{\mu}g/larva$. The larvae growth pattern shown a logarithmic phase from D shape to umbone stage but after that stage shown a exponential growth aspect. The crude protein, crude lipid and nitrogen free extract (NFE) of larvae during rearing periods were analyzed as $6.1{\sim}10.6%$, $0.6{\sim}1.1%$ and 1.0-2.7%, respectively. And the total amino acid contents of the larvae during rearing periods were in order as glutamic acid $1.26{\sim}2.24%$, aspartic acid $0.97{\sim}1.70%$, and methionine $0.12{\sim}0.33%$. Of the total fatty acid in the analyzed larvae, the saturated fatty acid (SSAFA) was decreased from 54.3% (D shaped larvae) to 17.1 % (pediveliger) as larvae development but the total mono-unsaturated fatty acid (${\Sigma}MOFA$) and Poly-unsaturated fatty acid (${\Sigma}PUFA$) were increased from 29.9% and 7.8% to 40.6% and 45.6%, respectively. By the way the each fatty acid of the larvae were composed of palmitic acid $9.89{\sim}36.95%$, oleic acid $12.17{\sim}32.29%$, linoleic acid $1.96{\sim}33.55%$, EPA $2.17{\sim}11.58%$ and DHA $1.95{\sim}4.51%$. As a result of this study, the larvae of oyster were demanded a various nutrients for healthy growth and the feeding control, expecially after umbone stage larvae are a rapidly growing time, is very important for success of artificial seed production.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.7
• /
• pp.980-989
• /
• 2016

In the present study, we compared and investigated the nutritional compositions of Amaranthus cruentus and Amaranthus hypochondriacus baby-leaves cultivated in Korea. Baby-leaves of two amaranthes consisted of more than 92% moisture, and A. cruentus contained a higher amount of moisture than A. hypochondriacus. Meanwhile, A. hypochondriacus contained higher levels of crude ash, crude protein, crude lipid, carbohydrates, and dietary fiber than A. cruentus. The major free sugars of the two amaranth baby-leaves were fructose and glucose. Fructose content of A. hypochondriacus was higher than that of A. cruentus, and glucose content of A. cruentus was higher than that of A. hypochondriacus. Acetic acid, malic acid, and fumaric acid were detected in two amaranth leaves, but succinic acid was not detected. Two amaranth leaves contained 17 amino acids except for methionine, proline, and tyrosine, and leaves contained the highest glutamic acid contents. In addition, A. cruentus and A. hypochondriacus leaves contained high contents of taurine and ${\gamma}$-aminobutyric acid and showed various biological activities. The major mineral and fatty acid of the two amaranth leaves were potassium and linolenic acid (C18:3), respectively. The ${\beta}$-carotene contents of A. cruentus and A. hypochondriacus leaves were $478.72{\mu}g/100g$ and $474.12{\mu}g/100g$, respectively. In vitamin B complex, $B_2$, $B_3$, and $B_5$ were detected in the two amaranth leaves whereas vitamins $B_1$, $B_6$, and $B_{12}$ were not detected. A. hypochondriacus contained higher amounts of vitamin C and E than those of A. cruentus. Overall, amaranth leaves contained high amounts of nutritional components. Therefore, amaranth leaves are expected to be useful for the development of a functional food. Moreover, these results will provide fundamental data for advancing sitological value, breeding new cultivars, and promoting leafy vegetable usage.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.26 no.4
• /
• pp.296-304
• /
• 1993

The effects of pretreatment on the lipid oxidation of korean geoduck muscle during storage at $-20^{\circ}C$ were investigated. In the lipid compositions of geoduck muscle, neutral, glycolipid, and phospholipid contents were $46.1\%,\;4.5\%\;and\;49.5\%$, respectively. And the content of phospholipid decreased to $39.9\%$ by blanching. In the fatty acids composition, $C_{16:0},\;C_{20:5}\;and\;C_{22:6}$ fatty acids were major portions and their contents showed, respectively, $10\%$ of total fatty acids amount or more. $C_{18:0},\;C_{16:1},\;C_{18:1},\;C_{14:0}\;and\;C_{20:1}$ fatty acids were also important fatty acids and their amounts were so much as $5\%$ or more. The polyunsaturated fatty acid contents were relatively high as $39.25\%{\sim}42.60\%$. POV in RM and VM samples increased gradually and showed 3.72meq/kg, or 3.00meq/kg after 90 days storage, respectively. However, in case of samples pretreated by blanching, there was slightly increase of POV throughout storage. From the results above, it was suggested that the pretreatment of blanching was effective in retardation of lipid oxidation for the longterm storage.

• Applied Biological Chemistry
• /
• v.27 no.4
• /
• pp.225-230
• /
• 1984

Chemical composition of dried roots of wild and cultivated Codonopsis lanceolata has been investigated. General composition was similar in both Codonopsis lanceolata. Free sugars from the root were fructose, glucose and sucrose. The contents of the sugars were higher in the cultivated than in the wild. Maltose was detected only in the cultivated and its level was 0.05%.. Free amino acids were consisted of 16 amino acids: lysine, histidine, arginine aspartic acid, threonine, serine, glutamic acid. proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine and phenylalanine. No significant difference in the contents was found between the wild root and the cultivated. Free fatty acids were palmitate, linoleate and linolenate, and the contents of those acids were higher in the cultivated root than in the wild. The contents of crude saponin were 1.5% in the wild root and 1.4% in the cultivated, respectively.

• The Korean Journal of Food And Nutrition
• /
• v.20 no.3
• /
• pp.245-252
• /
• 2007

This study investigated the effects of conjugated linoleic acid(CLA) on the fat deposition, triglyceride levels and the expression of stearoyl-CoA desaturase 1(SCD1) in the livers of male ICR mice that were fed with either soybean oil or beef tallow supplemented with CLA. Mice weighing $25{\sim}30$ g were divided into four groups; soybean oil(SBO), and SBO supplemented with 1% CLA(SBOC), beef tallow(BT) and BT supplemented with 1% CLA(BTC). Each group consisted of 10 mice that were fed the experimental diets for 4 weeks. The experimental diets consisted of 64% carbohydrate, 20% protein, and 16% fat in terms of their contributions to total calories. All other nutrients were identical in the diets. Triglyceride measurements were completed using a kit. Fatty acid compositions were analyzed in the liver using gas chromatography. The levels of SCD1 expression were analyzed by RT-PCR in the liver. No significant differences were found for food intake level, body weight and food efficiency among the experimental groups. However, the weights of epididymal fat pads and plasma triglyceride levels were significantly lower in SBOC and BTC(p<0.05) compared to the SBO and BT groups. These effects were similar in the CLA supplemented groups. The expression level of SCD1 gene and ${\Delta}9$ desaturase index were not significantly different, regardless of the fat used for CLA supplementation. Based on these results, addition of CLA showed decreasing effects on the fat depots weight and the concentration of triglyceride regardless of the fat sources. The SCD1 gene expression and ${\Delta}9$ desaturase index were not influenced by the types of fats with respect to the CLA effects.

• Journal of Animal Science and Technology
• /
• v.50 no.4
• /
• pp.519-526
• /
• 2008

Although beef provides high quality proteins as well as vitamins and minerals, its concentrations of saturated fatty acids and cholesterol give negative impression to some consumers on the other hand. Excess fat, especially cholesterol contents in beef is related with metabolic diseases such as atherosclerosis and hypertension. Unfortunately, the data for the relationship of marbling degree and cholesterol contents in Hanwoo beef is very limited. The objectives of the current study were to provide basic data about cholesterol contents in Hanwoo beef and to compare those among beef cattle breeds using 61 Hanwoo and 15 each of Angus and Wagyu crossbred steers. Samples were collected from M. longissimus area and cholesterol concentrations and fatty acid compositions were analyzed using gas chromatography. Cholesterol concentrations in Hanwoo beef ranged from 32.36 mg/100g to 75.42mg/100g depending on individuals. In Angus, cholesterol contents in lowest marbling degree of “Practically devoid” was 56.84mg/100g, whereas it was 72.85mg/100g in the highest marbling degree of “Abundant” showing increase in cholesterol concentrations as the marbling degree increases. For Wagyu crossbred steers, it was 69.23mg/100g and 78.93 mg/100g for marbling degree of “Practically devoid” and “Abundant”, respectively, showing similar cholesterol concentrations to Angus steers but still much higher than Hanwoo steers. The ratio of unsaturated fatty acids:saturated fatty acids for Hanwoo, Angus and Wagyu Crossbred were 1,48, 1.08 and 1.17, respectively. And the ratio of monounsaturated fatty acids : saturated fatty acids were 1.41, 1.03, and 1.10, respectively showing significantly higher ratios in Hanwoo steers. In conclusion, cholesterol contents and saturated fatty acids in M. longissimus of Hanwoo steers were significantly lower while unsaturated fatty acids were higher comparing to those in Angus or Wagyu Crossbred steers. Further studies, however, considering genetic backgrounds, feeding conditions, slaughtering age, number of samples and location of sampling of experimental animals are necessary.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.11
• /
• pp.1582-1588
• /
• 2005

This study aimed to evaluate the effects of silage additives on the fermentation qualities and residual mono- and disaccharides composition of silages. Forage Oats (Avena sativa L.) and Italian Ryegrass (Lolium multiflorum Lam.) were ensiled with glucose, sorbic acid and pre-fermented juice of epiphytic lactic acid bacteria (FJLB) treatments for 30 days. In both species grass silages, although the respective controls had higher contents of butyric acid (20.86, 33.45g $kg^{-1}$ DM) and ammonia-N/total nitrogen (100.07, 114.91 g $kg^{-1}$) as compared with other treated silages in forage oats and Italian ryegrass, the fermentation was clearly dominated by lactic acid bacteria. This was well indicated by the low pH value (4.27, 4.38), and high lactic acid/acetic acid (6.53, 5.58) and lactic acid content (61.67, 46.85 g $kg^{-1}$ DM). Glucose addition increased significantly (p<0.05) lactic acid/acetic acid, and significantly (p<0.05) decreased the values of pH and ammonia-N/total nitrogen, and the contents of butyric acid and volatile fatty acids as compared with control, however, there was a slightly but significantly (p<0.05) higher butyric acid and lower residual mono- and di-saccharides as compared with sorbic acid and FJLB additions. Sorbic acid addition showed the lowest ethanol, acetic acid and ammonia-N/total nitrogen, and highest contents of residual fructose, total mono- and di-saccharides and dry matter as well as high lactic acid/acetic acid and lactic acid content. FJLB addition had the lowest pH value and the highest lactic acid content, the most intensive lactic acid fermentation occurring in FJLB treated silages. This resulted in the faster accumulation of lactic acid and faster pH reduction. Sorbic acid and FJLB additions depressed clostridia or other undesirable bacterial fermentation, thus this decreased the water-soluble carbohydrates loss and saved the fermentable substrate for lactic acid fermentation.

• Journal of Dairy Science and Biotechnology
• /
• v.16 no.2
• /
• pp.119-136
• /
• 1998

The lipids of milk provide energy and many essential nutrients for the newborn animal. They also have distinctive physical properties that affect the processing of dairy products. Milk fat globules mainly consist of neutral lipids like triacylglycerols, whereas the globule membranes contain the complex lipids mostly, Phospholipids are a small but important fraction of the milk lipids and are found mainly in the milk fat globule membrane and other membranous material in the skim-milk phase. The milk fats of ruminant animals are characterized by the presence of relatively high concentrations of short-chain fatty acids, especially butyric and hexanoic acids, which are rarely found in milks of non-ruminants. The fatty acids of milk lipids arise from de novo synthesis in the mammary gland and uptake from the circulating blood. The fatty acid compositions of milks are usually complex and distinctive, depending on the nature of the fatty acids synthesized de novo in the mammary gland and those received from the diet in each species. The content and composition of milks from different species vary widely; presumably, these are evolutionary adaptations to differing environments. The actual process by which these globules are formed is unkonwn, but there are indications that triglyceride-containing vesicles which bleb from endoplasmic reticulum may serve as nucleation sites for globules. Recent studies on milk have centred on the manipulation of milk lipids to increase specific fatty acids, i.e. 20-carbon omega-3 fatty acids (eicosapentaenoic acid 20:5n3, decosahexaenoic acid 22:6n3) from marine sources because the fatty acids are closely associated with a decreased risk of coronary heart disease.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.1
• /
• pp.30-36
• /
• 1999

Seasonal variation in lipid classes and fatty acid compositions of total lipid (TL) of 12 species of Korean fish muscle, which caught off Tongyeong coast of the Southern Sea (Nam-Hae) from Mar, 1995 to Feb. 1996, was studied. Triglyceride (TG) and free sterol (ST) were prominent lipid classes of neutral lipid in all fish species. The percent of TG rose with increasing TL content by season, but that of ST fell. The prominent lipid classes of phospholipid were phosphatidylcholine (PC) and phosphatidylethanolamine (PE), percents of PC and PE were higher in the fish containing lower lipid. The prominent fatty acids in all fish species were 16:0 ($19.5\pm1.99\%$) 22:6 (n-3) ($16.6\pm7.46\%$), 18:1 (n-9) ($15.8\pm8.39\%$), 20:5 (n-3) ($8.46\pm3.70\%$), 16:1 (n-7) ($7.06\pm3.08\%$) and 14:0 ($3.80\pm2.15\%$). With increasing TL content by season, the percent of monounsaturated fatty acids (MUFA) such as 18:1 (n-9) and 16:1 (n-7) rose, but those of polyunsaturated fatty acids (PUFA) such as 22:6 (n-3) and 20:5 (n-3) fell. There was a negative correlation between the percent of the MUFA and the PUFA of total fatty acids. However, the PUFA content increased as the TL content increased by season. On the other hand, the percent of 16:0 almost unchanged by seasonal variation of lipid content.