• Korean Journal of Food Science and Technology
• /
• v.47 no.2
• /
• pp.191-197
• /
• 2015

We investigated the physicochemical properties and volatile flavor compounds in Taiwan Apple Mango (TAM) and Philippines Carabao Mango (PCM). The volatile flavor compounds were extracted using solid-phase microextraction (SPME) and analyzed by GC/MS. TAM and PCM have significantly different chemical composition, except for their crude ash. The moisture and crude fat contents were higher in TAM, whereas the crude protein and carbohydrate contents were higher in PCM. The major free sugars in order of concentration were sucrose, fructose, and glucose. We identified 56 and 59 volatile flavor compounds in TAM and PCM, respectively. Terpenes and their derivatives comprised 94.42% of the volatile flavor compounds in TAM, but only 63.79% of those in PCM. The acidic compound contents were higher in PCM than in TAM. ${\delta}$-3-Carene was the dominant flavor compound in these two mango cultivars. ${\alpha}$-Copaene, ${\alpha}$-guaiene, germacrene D, ${\alpha}$-bulnesene, and ${\gamma}$-gurjunene were found only in TAM, whereas ${\beta}$-myrcene, ${\alpha}$-phellandrene, ${\beta}$-phellandrene, ${\alpha}$-terpinolene, and cis-3-hexenyl butyrate were identified in PCM. Based on the results, we suggest that these compounds might contribute to the distinguishing flavor properties in different varieties of mango.

• Korean Journal of Microbiology
• /
• v.42 no.1
• /
• pp.47-53
• /
• 2006

A streptomycete strain was isolated from the soil samples from Korea. The chemotaxonomy and 16S rDNA sequencing confirmed that the strain belonged to the genus Streptomyces and we named it Streptomyces sp. AO-0511. Two antibiotics, herbimycin A and dihydroherbimycin A produced by this strain were tested for their physico-chemical and biological characteristics. Both compounds were stable under acidic pH. Dihydroherbimycin A was more heat-stable and polar compared with herbimycin A. Only weak antibacterial activities were detected against Bacillus subtilus ATCC 6633 and Micrococcus luteus ATCC 9341. However, herbimycin A and dihydroherbimycin A showed strong inhibitory activities on lung cancer cells (A549 cells) and leukemia cells (HL-60). The cytotoxicity was determined using L5178Y and P388 cell lines. The results showed that herbimycin A and dihydroherbimycin A had lower toxic effects on the cells compared with the standard compounds, comptothecin and cyclosporin A. Therefore, both compounds could be good candidates for the development of new anticancer drugs.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.19 no.6
• /
• pp.547-554
• /
• 1990

The precursor substance and volatile components of cooked flavor of squid meat were studied. Volatile components were trapped by simultaneous distillation-extraction method, and these were fractionated into the neutral, basic, phenolic and acidic fraction. Volatile flavor components in these frations were analyzed by GC and GC-MS. 80％ methanol solution was the most effective solvent for extraction of the precursor substance for cooked flavor. The neutral and basic fraction, by organoleptic test, seem to have a major effect on squid-like flavor. Forty-four compounds, including 2 hydorcarbons, 10 alcohols, 5 aldehydes, 1 ketone, 1 furan, 3 sulfide compounds, 7 pyrazines, 2 pyridines, 1 amino, 2 phenols and 10 acids, identified as cooked flavor compounds of squid meat.

• Clean Technology
• /
• v.9 no.2
• /
• pp.63-69
• /
• 2003

The metal finishing industry generates a variety of pollutants such as acidic or alkaline wastewater, chromic compounds, cyanide, heavy metals, and toxic materials. Especially, zinc plating process is one of the processes which cause serious environmental problems. In this study, we applied the proven optimum technology to important unit processes in terms of implement effects through the process diagnosis and analysis. This study aimed to improve the working environment and the environmental pollutions in zinc plating process.

• KSBB Journal
• /
• v.15 no.3
• /
• pp.293-298
• /
• 2000

${\beta}$-Glucan a kind of polysaccharide which is particularly abundant in Agaricus blazei is known as the bioactive materials especially anticancer agents. The process development of the isolation and the purification process of water soluble ${\beta}$-glucans from A. blazei was achieved. and the process operation variables were optimized. Crude polysaccharides (CR.PS) were obtained from A. blazei by hot water extraction filtration solvent precipitation dialysis and freeze drying. Neutral and acidic fraction of polysaccharides were separated from crude polysaccharides by ion chromatography and then high molecular weight and low molecular weight fraction were separated from neutral fraction by gel chromatography. Quantitative and qualitative analysis of each compounds were performed with FT-IR NMR spectroscopy. Based on these analysis the optimal conditions of temperatures operating time organic solvent volume for precipitation and dialysis time were determined.

• Journal of Ginseng Research
• /
• v.37 no.1
• /
• pp.117-123
• /
• 2013

Polyphenol oxidase (PPO) was purified from fresh ginseng roots using acetone precipitation, carboxymethyl (CM)-Sepharose chromatography, and phenyl-Sepharose chromatography. Two isoenzymes (PPO 1 and PPO 2) were separated using an ion-exchange column with CM-Sepharose. PPO 1 was purified up to 13.2-fold with a 22.6% yield. PPO 2 bound to CM-Sepharose, eluted with NaCl, and was purified up to 22.5-fold with a 17.4% yield. PPO 2 was further chromatographed on phenyl-Sepharose. The molecular weight of the purified PPO 2 from fresh ginseng was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was about 40 kDa. The optimum temperature and pH were $20^{\circ}C$ and 7.0, respectively, using catechol as a substrate. Pyrogallol showed the highest substrate specificity. The effect of a PPO inhibitor showed that its activity increased slightly in the presence of a low concentration of citric acid. High concentrations of acidic compounds and sulfite agents significantly inhibited purified ginseng PPO 2.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2003.05a
• /
• pp.89-90
• /
• 2003

Fermented fish (jeotkal) has been used as a method of preserving perishable fish and marine products. Recently, however, high salted jeotkal (20% and more) has avoided from consumer by reasons of organoleptic quality (high salinity), health value (degenerative chronic disease), and hygienic safety. Among these jeotkals, meanwhile, sikhae (lactic acid fermented fishes) has been traditionally favored in the eastern coastal area of Korea, which contain below 10% of salt content with acidic range (pH4∼5). (omitted)

• Analytical Science and Technology
• /
• v.13 no.5
• /
• pp.549-557
• /
• 2000

FRIR-ATR spectrometry has been used to monitor the aqueous reactions of compounds without distinct chromophores in ultraviolet and visible regions. For example, hydrolysis reactions of ${\alpha}$-cyclodextrin and ${\gamma}$-cyclodextrin in acidic aqueous solution were studied. FTIR-ATR method has been used for the monitoring of cyclodextrin hydrolysis in 1.0 M. 0.5 M, and 0.1 M HCl solutions, respectively. We also found that the hydrolysis of ${\alpha}$-cyclodextrin produced glucose, but the hydrolysis of ${\gamma}$-cyclodextrin proceeded further to give more fragmented products than glucose.

• Food Science and Biotechnology
• /
• v.18 no.6
• /
• pp.1495-1499
• /
• 2009

The volatiles formed from the reactions of L-ascorbic acid with L-alanine at 5 different pH (5, 6, 7, 8, or 9) and $140{\pm}2^{\circ}C$ for 2 hr was performed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis were identified to be 25 different kinds. The reaction between L-ascorbic acid and L-alanine led mainly to the formation of pyrazines. Many of these were alkylpyrazines, such as 3-ethyl-2,5-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine, 3,5-diethyl-2-methylpyrazine, methylpyrazine, 2-ethyl-6-methylpyrazine, and 2,3-diethyl-5-methylpyrazine, other compounds identified were furans, phenols, benzoquinones, 2,4,6-trimethylpyridine, and 2-methylbenzoxazole. The studies showed that furans, such as furfural and benzofuran were formed mainly at acidic pH. In contrast, higher pH values could promote the production of pyrazines.

• Journal of the Korean Home Economics Association
• /
• v.23 no.3
• /
• pp.85-101
• /
• 1985

1. Nitrate and nitrite may contribute via nitrosation to the human exposure to N-nitroso compounds, especially nitrosamines, which are suspectd to be human carcinogens. 2. Since certain foods contain traces of nitrosamines, one should take the several points into consideration in evaluating the risk. 3. Nitrites, which can appear in the because of natural occurrence or deliberate addition, can react under the acidic conditions of the normal stomach with secondary amines to form nitrosamine. 4. Among the foods esamined, nitrate-nitrite treated meat products cooked bacon, and salted and dried fish are the main contributors of nitrosamines in our diet. 5. Consequently, in order to minimize human exposure to these chemicals, it is obviously essential to develop the alternative sources of nitrite in cured meat products. Thus the emphasis should be placed upon the most effective use of nitrite in curing with the use of acceptable inhibitors of nitrosation such as ascorbc acid or $\alpha$-tocopherol.