• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.19 no.3
• /
• pp.227-233
• /
• 1986

The compositions and seasonal variations of free sugars and non-volatile organic acids of brown algae, such as Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides were investigated by gas chromatography. Four kinds of free sugars, such as xylose, glucose, galactose and floridoside were identified. The most abundant one was floridoside marking 118.7 mg/100 g, 90.9 mg/100 g and 70.0 mg/100 g in Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinguishable seasonal variations in the contents of free sugars in all the samples. In the case of organic acids, nine kinds were identified in Ecklenia cava and major ones were succinic, citric, malic, fumaric, oxalic and lactic acid, of which succinic acid was the most abundant one marking $30.6\%$ of total organic acids. In Sargassum ringgoldianum and Myagropsis myagroides, eight kinds were identified, which major ones were succinic, citric and malic acid in both samples, and they marked $68.4\%$ and $61.1\%$ of total organic acids in Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinct changes in the content of total organic acids according to seasons in all the samples examined. The contents of total organic acics in Ecklonia cava was a little more than Sargassnm ringgoldianum and Myagropsis myagroides.

• Food Science and Preservation
• /
• v.24 no.6
• /
• pp.802-812
• /
• 2017

This study was conducted to investigate the quality properties depending on the cultivation methods (general, organic, pesticide-free) of yuza and its various parts (peel, pulp, seed). The contents of hesperidin were the highest in yuza feel grown by pesticide-free method (13.23 mg/g). The contents of naringin presented a higher content in the peel, especially which of the general (4.62 mg/g) showed the highest value. Vitamin C analysis showed the highest content in the peel, significantly varied according to the cultivation method and various parts (p<0.05). Vitamin C value was significantly highest in organic peel, which was 770.02 mg/100 g, whereas among the peel, the pulp and the seed were it the lowest in the seed. The content of total polyphenols were the highest in general peel (0.85 mg/g). Flavonoid content of pesticide-free seed was significantly higher than those of the other yuja samples which was 0.89 mg/g (p<0.05). The DPPH radical scavenging activity was relatively more active in the peel among the above-mentioned three parts, especially the pesticide-free peel was most active, which was 73.94%. The ABTS radical scavenging activity of organic peel was significantly active among the samples, which was 84.47% (p<0.05). Based on these results, it can be said that yuja has variety of useful components in the pulp and the seed as well as the peel: and thus it's hight recommended to develop more varied yuja products.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.8
• /
• pp.1037-1043
• /
• 2008

In this experiment, citrus juice was fermented by Gluconacetobacter hansenii TF-2, an isolate from tea fungus to develop a new type of acidic beverage. The juice broth is made by fermenting of $11{\sim}17%$ (v/v) juice and sweetened with sucrose (initial sucrose $10^{\circ}Brix$). The fermentation by G. hansenii TF-2 was initiated by adding 5% (w/v) of seed gel (pellicle, tea fungus) which was previously cultured in the same medium (fresh juice broth) and the fermentation was carried out in a dark incubator at $28{\sim}30^{\circ}C$ for about 15 days. During the fermentation a pellicle grew on the surface of the fermenting fluid and acids were produced. Fermented fluid (beverage) was centrifuged at 7,000 rpm for 15 min for further analyses. The highest amount of the other metabolites including organic acids were observed in 5 to 10 days. Major acids were acetic acid (fermented citrus beverage, CB). After 15 days of fermentation, organic acid content such as acetic acid in fermented beverage was measured to be $183.5{\sim}186.6\;ppm$. Free sugars content in CB were 56.8%, 35.1%, 40.7% and 63.2% of unfermented sucrose, glucose, fructose and sorbitol, respectively. When the growth rate of inhibitory effect of the fermented beverage was measured by using several species of food-related bacteria, the beverage fermented with CB exhibited the strongest inhibition against gram-negative (E. coli and Sal. Typhimurium). Its inhibition rate was between $71.9{\sim}94.0%$ at CB. Fermented beverage has shown effectiveness for antimicrobial activity against some species of food-related bacteria.

• KSBB Journal
• /
• v.17 no.2
• /
• pp.182-188
• /
• 2002

Enterococcus faecalis RKY1 cells were immobilized in an asymmetric hollow fiber bioreactor for application to the continuous production of succinic acid. The media was fed into shell-side of the module using a peristaltic pump, and the products were collected through lumen-side outlet. The number of hollow fibers within the module did not affect the bioreactor efficiency in the transverse operated hollow fiber bioreactor. The steady state at the outlet of hollow fiber bioreactor was reached after 24 hr cultivation at flow rate of 0.25 mL/mim, 12 hr at 0.5 L/min, and 9 hr at 1.0 mL/mm, respectively. The succinate and fumarate concentrations within the hollow fiber bioreactor, however, were as changeful as increasing the flow rate. During continuous operation with the flow rates between 0.5 and 2.0 mL, the productivity of succinate was 8.0-10.9 g/L $.$ hr at 30 g/L fumarate, 4.9-14.9 g/L hr at 50 g/L fumarate, and 7.2-17.1 g/L hr at 80 galL fumarate, respectively.

• Korean Journal of Food Science and Technology
• /
• v.26 no.2
• /
• pp.157-161
• /
• 1994

The pigments of acetylshikonin and isobutylshikonin isolated from the roots of Lithospermum erythrorhizon were determined over a period of storage for their stabilities influenced by mono- and disaccharides and acids. In general. sugars and acids caused an increase in stability of acetylshikonin at the various concentrations. These studies indicated that acetylshikonin and isobutylshikonin can be used in foods as the natural colorant under selected conditions.

• The Korean Journal of Food And Nutrition
• /
• v.16 no.1
• /
• pp.29-34
• /
• 2003

Prunus mume has been used for the folk medicine by many old civilizations to treat food-borne diseases or enteric disorders. This study was carried out to examine the antimicrobial effect of juice from Prunus mume against pathogens such as Escherichia coli, Salmonella enteritidis, Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus. The juice of Prunus mume had the strongest antimicrobial activity to Sal. enteritidis. The concentrations of Prunus mume juice for the formation of clear zone were 1% for Sai. enteritidis(15.0mm), 3% for Lis. monocytogenes(14.7mm), and 5% for Bac. cereus(14.75mm), Esc. coli(13.45mm) and Sta. aureux(11.9mm). The growth of all tested microorganisms was inhibited apparently in tryptic soy broth containing 3% and 4% Prunus mume juice. And it was found that the Prunus mume juice showed the highest antimicrobial properties, followed by Sal. enteritidis, Bac. cereus, Sta. aureus, Lis. monocytogenes, Esc. coli.

• Journal of The Korean Society of Inherited Metabolic disease
• /
• v.12 no.1
• /
• pp.23-34
• /
• 2012

Purpose: Acute symptomatic seizures are caused by structural changes, inflammation or metabolic changes of brain, such as tumor, stroke, meningitis, encephalitis and metabolic disorders. Inherited metabolic disorders that can cause seizures are organic acidopathies, lysosomal storage disorders, peroxisomal disorders and mineral disorders. We have done this study to find out the importance of organic acidopathies causing seizure disorders in Korean childhood and adolescent patients. Method: Retrograde analysis for 1,306 patients with seizure disorders whose clinical informations are available and have done urine organic acid analysis for 5 years period, between Jan. 1st 2007 to Dec. 31th 2011. Statistical analysis was done with Student's t test using SPSS. Result: Out of 1,306 patients, 665 patients (51%) showed abnormalities on urine organic acid analysis. The most frequent disease was mitochondrial respiratory chain disorders (394, 30.1%), followed by mandelic aciduria (127, 9.7%), ketolytic defects (81, 6.2%), 3-hydroxyisobutyric aciduria (19, 1.4%), glutaric aciduria type II (10, 0.8%), ethylmalonic aciduria (4), propionic aciduria (4), methylmalonic aciduria (3), glutaric aciduria type I (3), pyruvate dehydrogenase deficiency (3), pyruvate carboxylase deficiency (3), isovaleric aciduria (2), HMG-CoA lyase deficiency (2), 3-methylcrotonylglycinuria (2), fatty acid oxidation disorders (2), fumaric aciduria (1), citrullinemia (1), CPS deficiency (1), MCAD deficiency (1). Conclusion: On neonatal period, mandelic aciduria due to infection was found relatively frequently. Mitochondrial disorders are most frequent etiologic disease on all age group, followed by ketolytic defects and various organic acidopathies. The number and diversities of organic acidopathies emphasize meticulous evaluation of basic routine laboratory examinations and organic acid analysis with initial sample on every seizure patient.

• Applied Biological Chemistry
• /
• v.13 no.1
• /
• pp.1-27
• /
• 1970

The process of the forced aging of flue-cured tobacco leaves were studied extensively from various scientific points of view. The Flue-cured tobacco leaves were inoculated and fermented with nicotine resistant Hansenula yeast, or the leaves were subjected under simple forced aging. The above two processes of forced aging were studied from the summarized points of microbiology, physics, chemistry, and biochemistry, and the resulted products ware compared in their physical, chemical and biochemical quality determining factors with that of raw material tobacco leaves (dried-tobacco leaves) and 2 years aged high quality tobacco leaves. The summary results were as follows. 1) The Korean flue-cured tobacco leaves, were forcedly aged under the basic optimum aging condition, temperature $40^{\circ}C$, moisture contents 18%, relative humidity 74%. It was found that this aging condition was the best in bringing the quality of forcedly aged tobacco leaves to the utmost state. 2) Under this optimum temperature and moisture condition of forced aging in about 20 days the forcedly aged tobacco leaves both with yeast inoculation and without yeast inoculation showed the equivalent tobacco qualities comparable with that of more than 2 years aged tobacco leaves. 3) The forcedly aged tobacco leaves both with and without yeast inoculation under $40^{\circ}C$ temperature and $74^{\circ}C$ relative humidity achieved the necessary quality determining physical and chemical changes in about 20 days. 4) The microbial changes during the forced aging were as follows. The population of yeasts and bacteria increased until to 15 days of aging, then decreased thereafter. Whereas the molds grew continously until the end of fermentation. 5) The tobacco quality determing physico-chemico-properties of yeast inoculated aged and simple forcedly aged tobacco leaves, progressed as the follows in time. As the forced aging progresses, swelling and combustibility properties were improved. The pH, total reducing materials, total sugars, alkaloids contents decreased. The contents of organic and ether extractable materials increased. The total nitrogen, protein, crude fiber, ash contents showed no changes. The color properties, excitation purity, luminance, main wave length, showed equivalent changes comparable with that of 2 years aged tobacco leaves. 6) The changes in chemical components in yeast treated and simple forcedly aged tobacco leaves during $15{\sim}20{\;}days$ of forced aging were as follows. The following chemical components decreased as the aging. Sugars-sucrose. rhamnose, glucose. Pigments-chlorophyll, carotenes, xanthophyll and violax anthine. Polyphenols-rutin, chlorogenic and, coffeic acid. Organic acids-iso-butylic, crotonic, caprylic, galacturonic, tartaric, succinic, citric acid. Alkaloids-nicotine, nornicotine. The following components increased as the forced aging progressed. Sugars-frutose, maltose, raffinose. Amino acids-proline, cystine. Organic acids-formic, acetic, propionic, n-butyric, iso-valeric, n-valeric, malic, oxalic, malonic, ${\alpha}-ketoglutaric$, fumaric, glutaric acid. 7) During the forced aging of tobacco Leaves the oxygen-uptake decreased gradually. The enzyme activities of polyphenol oxidase, ${\beta}-amylase$ ${\alpha}-amylase$ decreased gradually. The activities of the enzymes, catalase, and invertase increased once then decreased at the later stage.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.15 no.4
• /
• pp.298-302
• /
• 1982

In order to elucidate the taste compounds of wild common carp, Cyprinus carpio, and Korean snakehead, Channa argus, organic acids, sugars ana minerals were analyzed as a part of the study on the taste compounds of fresh-water fishes. Among organic acids, the contents of succinic acid, butyric acid, propionic acid and valeric acid were fairly high, while those of oxalic acid, fumaric acid, maleic acid, tartaric acid and citric acid were trace. As for the sugars, glucose was found to be the most predominant monosaccharide of the species. Extremely small amounts of fructose and arabinose were also detected and inositol and ribose were trace in content. Among minerals, $K^{+},\;Na^{+},\;PO_{4}^{3-}\;and\;Cl^{-}$ were found to be the major ions and small amounts of $Ca^{2+}\;and\;Mg^{2+}$ were detected.

• Microbiology and Biotechnology Letters
• /
• v.11 no.1
• /
• pp.53-58
• /
• 1983

Sik-hae is a traditional Korean fermented fish product which is made from flat-fish, garlic, salt, red pepper and millet. The changes in chemical composition, pH, acidity and the contents of Amino-N, VBN, TMA and organic acids were investigated during the fermentation of Sik-hae. The changes in the microflora, enzyme activity and the sensory quality including textural characteristics were also evaluated. The changes in the contents of crude protein, crude fat and moisture during Sik-hae fermentation were negligible. The pH of the product tended to decrease in the course of fermentation and it showed the minimum value of 4.5 after 7 days of fermentation. On the other hand the acidity continued to increase up to 2300mg % by 4 weeks of fermentation. Lactic acid was the major organic acid. The content of Amino-N in sik-hae gradually increased up to 673.6mg % by 2 weeks of fermentation, and then slightly decreased. The content of VBN increased rapidly during the first 2 weeks of fermentation, while little changes in TMA content was observed. The number of proteolytic bacteria increased slightly for the first 2 weeks and then rapidly decreased. The number of yeast and acid forming bacteria increased rapidly from the 4th day to the 14th day of fermentation and then decreased. Both lipase and protease activities showed the maximum at the 11th day of fermentation. The texture softening of the fish occurred after 1 week of fermentation and the adhesiveness appeared after 2 weeks of fermentation. Summarizing these results, the optimum fermentation time for Sik-hae from flat fish were 2 weeks at 2$0^{\circ}C$ and the quality of the product could be kept for up to 4 weeks in refrigerator.