• Food Engineering Progress
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• v.13 no.2
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• pp.138-146
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• 2009

The crude polysaccharide fraction from fruit body of Auricularia auricula were obtained by using hot water extraction and ethanol precipitation. As the crude polysaccharide fraction contained the brownish dark colored compounds, the adsorption study of pigments from the crude polysaccharide using activated carbon was carried out. The pigment compounds showed an absorption characteristic with $\lambda_{max}$ of 230 nm and the absorbance at 230 nm was taken as color intensity. Adsorption capacity of pigment depended on increase of the activated carbon to sample loading ratio. The adsorption capacity increased with increase of pH and temperature in the pH range of 3.0-7.0 and temperature range of 25-40$^{\circ}C$, but decreased in the temperature range of 40-70$^{\circ}C$. The optimum capacity was obtained at addition of 16.7 mg activated carbon per mL sample solution (concentration = 3 mg/mL) at pH of 7.0 and temperature of 40$^{\circ}C$. Treatment for 10 min was sufficient to achieve the 80% decolorization and 1.25 fold purification of polysaccharide. Langmuir isotherm and pseudo second-order kinetic model provided the best fitting for adsorption of the brownish dark colored compounds onto powdered active carbon. The activation energies of adsorption from the Langmuir isotherm parameter in the ranges of 25-40$^{\circ}C$ and 40-70$^{\circ}C$ was -2.54 and 4.38 kcal/g, respectively. The results of low activation energy also indicated that the adsorption process was a physical adsorption which was controlled by diffnsion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.251-260
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• 1994

Lipophilic brown pigments produced during the fermentation of domestic Meju and Doenjang were fractionated by column and thin -layer chromatography (TLC). Each of the fractions was tested for the antioxidant activity and then characterized by spectroscopic analysis. The lipophilic brown pigments were separated into chloroform -soluble and methanol-soluble parts in which Meju resulted the higher content of chloroform-soluble part than that of methanol-soluble part ; however, Doenjang exhibited the opposite result to that of Meju. More strong antioxidant activity was found in the methanol-soluble part than the chloroform-soluble part. Four and five fractions were separated from chloroform-soluble and methanol-soluble parts respectively. by silicagel TLC. The fraction that exhibited the high antioxidant activity showed a strong absorption at 260nm caused by amino compounds in UV spectrum The other fractions which did not have antioxidant activity absorbed at 240nm by carbonic acid and it ester,. IR spectrum of each fraction commonly showed absorption at 3400cm-1 , 2800cm-1 , 1700cm-1, 1600cm-1, 1400cm-1 , 1300cm-1 and 1100cm-1. Especially , the fraction which had a strong antioxidant activity showed absorption at 2800cm-1, 1400cm-1, 1600cm-1 suggesting that the fraction contain Schiff's base and primary amine structure.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.604-613
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• 1994

Hydrophilic brown pigments(HBPs) produced during fermentation and aging the domestic Meju and Doenjang were separated by dialysis and chromatography , and their antioxidant activity were measured . The chemical properties of HBP were determined by UV and IR spectrophotometry. HBPs contents were found to be 93.1 mg/g and 183.2mg/g in Meju fermentated for 30 days and 80 days , respectively. The ratio of dialysate to diffusate of the HBPs were appeared to be 70 : 30 and 87 :13 in the Meju fermented for 30 days and 80 days, respectively. and the rtio in the Doenjang aged for 60 days was 91 :9 , indicating that dialysate slowly days, respectively, and the ratio in the Doenjang aged for 60 days was 91 : 9, incidatin that dialysate slowly increased by the fermentation . Both portion exhibited strong antioxidant activity, but more stronger antioxidant activity was found in the dialysate. DEAE-celluose column chromatography showed that dialysate contained more materials eluted by 0.01-0.03M HCI solution than 0.01M acetate buffer, but diffusate showed opposite results. The degree of browning reaction and antioxdiant activity found in the fraction eluted by HCI solution was stronger than that of the fraction eluted by acetate buffer. The fraction eluted from DEAE-cellulose column chormatogrphy was further fractionaged by TLC and found that strong antioxidant activity was present in the fractions which did not possess fluorescenece and showed a negative ninhydrin reaction. TLC fractions of HCI eluant in Meju exhibited a strong absorbance at 260-280nm, but most of other fractions did not show any absorbance at UV region. TLC fractions from dialysate and diffusate showed fairly identical IR spectrum with absorbance at 3400cm-1, 2800cm-3000cm -1, 1600cm, -1 1400cm-1 and 1100 cm-1 , however, in addition to these absorbances, the spectrum from HCI eluant of Meju exhibited a strong absorbance at 1750cm , indicating the carbonic acid or carbonate ester.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.246-252
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• 1996

Changes in physicochemical properties of the defatted sesame meals at various roasting temperature and time have been studied. The roasting temperatures were $190^{\circ}C,\;210^{\circ}C,\;and\;230^{\circ}C,$ whereas roasting times were 5, 10, 20 and 30 minutes, The protein content of defatted sesame meals decreased during roasting and the oil content of the meals roasted at$210^{\circ}C$ for 10 minutes was 8.4%. The yields of sesame mea]s and oil, when roasted at $210^{\circ}C$ for 10 minutes, were 50.1% and 46.9%, respectively. The amino acids in sesame meals gradually decreased as roasting conditions became severe. Sucrose (162.6 mg%), glucose (37.7 mg%) and fructose (18.7 mg%) were detected in the raw sesame meals. The color of roasted sesame seeds and oils extracted from them became darker as the roasting temperature and time increased and the change in lightness greatly affected the total color change. The browning pigment of the sesame meal roasted at $190^{\circ}C$ was separated into a fraction I, II and III. When roasted at $230^{\circ}C$ for longer than 10 minutes, the soluble browning pigment decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.17-22
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• 1977

In the present paper, the effect of sodium sulfite treatment on tile inhibition of browning reactions occurring in the storage of dried oyster was tested and the supplementary effect of antioxidantsaddedwasalsomentioned. Dried oysters treated with sodium sulfite solutions as described in the previous paper(Lee and Choi, 1977) were stored in the bottles with silica gel bags at room temperature with or without the application of antioxidants. The ethanol solution of an antioxidant mixture(BHA, BHT, plus, synergists) was sprayed on the surface of cooked oyster before drying. The density of brown pigment was determined spectrophotometrically by measuring the absorbance at 420 and 440 nm of both fractions of pigment extract, namely chloroform-methanol and water soluble fractions, which represent the brown color developed by fat oxidation and Maillard reactions respectively. TBA value was also measured for the oxidative rancidity in oysters during the storage. It appeared from the results that the 0.5 M sodium sulfite-60minute treated samples showed better effect after 150 day storage at room temperature. Controlling tile pH of treating solutions, did not reveal so much different in inhibitory effect in the aspect of color but a more reduction of tyrosine and reducing sugar was resulted with acidic solution than with alkaline solution. The development of brown color in dried oyster seemed to be leaded rather by the oxidative rancidity of lipids than sugar-amino reactions particularly in a long-term storage since the browning of chloroform-methanol fraction progressed more rapidly than of water. soluble fraction. The application of antioxidant, therefore, could largely retard the browning of the product as appeared in the results that sodium sulfite treated oyster with addition of antioxidant kept the best color during the storage.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.968-974
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• 2003

Twenty-three cultivars of colored rice were collected from inside and outside Korea to determine the contents of pigments and phenolic compounds, and also to compare their correlations with antioxidativity and antimutagenicity. The pigment content decreased in the order of LK 1-3-6-12-1-1>LK 1D 2-7-12-1-1>Elwee>Mutumanikam>IR 1544-38-2-2-1-2-2>wx 124-163-45-7-1-1-1, LK 1A-2-12-1-1. Polyphenolic content was the greatest in IR 17491-5-4-3-3 with a ratio of 0.244 g per 100 g brown rice, followed by LK 1-3-6-12-1-1>LK 1D2-12-1>Elwee>Mutumanikam 7 IR 1544-38-2-2-1-2-2, LK 1A-2-12-1-1. The pigment contents for each colored rice cultivar showed a highly positive correlation with polyphenolics in colored rice seeds. For chromaticity, a positive correlation was exhibited between the lightness and hydroxyl radical scavenging activity. In contrast, a negative correlation was observed between the redness and the inhibitory effect of lipid peroxidation.

• Korean Journal of Remote Sensing
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• v.15 no.3
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• pp.227-238
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• 1999

In advance of launch, simulated radiances of the Ocean Scanning Multispectral Imager (OSMI) will be very useful to guess the real imagery of OSMI and to prepare for data processing of OSMI. The data processing system for OSMI which is one of sensors aboard Korea Multi-Purpose Satellite (KOMPSAT) scheduled for launch in 1999 is developed based on the SeaWiFS Data Analysis System (SeaDAS). Simulation of radiances requires information on the spectral band, orbital and scanning characteristics of the OSMI and KOMPSAT spacecraft. This paper also describes a method to create simulated radiances of the OSMI over the oceans. Our method for constructing a simulated OSMI imagery is to propagate a KOMPSAT orbit over a field of Coastal Zone Color Scanner (CZCS) pigment concentrations and to use the values and atmospheric components for calculation of total radiances. A modified Brouwer-Lyddane model with drag was used for the realistic orbit prediction, the CZCS pigment concentrations were used to compute water-leaving radiances, and a variety of radiative transfer models were used to calculate atmospheric contributions to total radiances detected by OSMI. Imagery of the simulated OSMI radiances for 412, 443, 490, 555, 765, 865nm was obtained. As expected, water-leaving radiances were only a small fraction (below 10%) of total radiances and sun glint contaminations were observed near the solar declination. Therefore, atmospheric correction is critical in the calculation of pigment concentration from total radiances. Because the imagery near the sun's glitter pattern is virtually useless and must be discarded, more advanced data collection planning will be required to succeed in the mission of OSMI which is consistent monitoring of global oceans during three year mission lifetime.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.4
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• pp.294-299
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• 1987

Lipid composition of dried grasshopper which the most significant factor of quality deteriorioration for processing and storage were studied. Also brown pigment formation and its effect of lipid autoxidation were studied. Lipid contents of matured female grasshopper were revealed 5.12% and composed of high content of unsaturated fatty acid. The phospholipid comprised 27.35% of the total lipid. On sun ana hot ai' drying, carbonyl values were greatly increased but peroxide values were not determined. On freeze drying, lipid peroxide and carbonyl compounds in grasshopper lipids were nearly not accumulated. Peroxide values were increased during early stage of storage, but carbonyl values were steadly increased for 98 days. Hydrophilic brown pigments which caused by sugar-amino reaction were higher than that of lipophilic. In the water soluble fraction of the browning products has some autioxidative activity, but in liposoluble fraction has not.

• Journal of the Korean Society of Food Science and Nutrition
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• v.2 no.1
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• pp.41-47
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• 1973

In the present work, the quality stability of sun-dried Alaska pollack, Theragra chalcogramma, was discussed in the aspects of non-enzymatic discoloration as a function of relative humidity during storage at room temperature$(20^{\circ}C)$. Frozen Alaska pollack was dressed, filleted, dried for 48 hours in the open air, and finally stored in cylindrical acrylic chambers which contained saturated specific salt solutions proposed by Rockland(1960) for humidity control. The color development of the product was analyzed by spectrophotometry at 10 day-intervals during the storage. Lipid oxidation was measured as TBA value at wavelength of 538nm. And browning pigments were extracted, divided into two fractions and measured at 460nm: one was chloroform-methanol (2:1 v/v)soluble fraction attributed to lipid oxidation, and the other was water dialyzed fraction caused by so called Maillard reaction. The TBA value showed a maximum on 30 day storage, hereafter, intended to decrease gradually. On the other hand, the rate of brown pigment development in water dialyzed fractions as well as in chloroform-methanol soluble fractions was lower at 34 to 45%RH than at any other case, and propagation of lipid oxidation was also diminished at the same levels of humidity. From the facts described previously, it is recognized that storage at 34 to 45%RH provides higher quality stability for sun-dried Alaska pollack.

• KSBB Journal
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• v.29 no.5
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• pp.343-352
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• 2014

In the present study, antioxidant activities of two crude pigments (acetone and MeOH) and their solvent fractions (n-hexane, 85% aq.MeOH, n-BuOH, and water fractions) from red crab shell were evaluated by measuring 1,1-diphenyl-2-picryl hydrazyl (DPPH), peroxynitrites, and degree of production of reactive oxygen species (ROS) in HT 1080 cells as well as the extent of oxidative damage of genomic DNA purified from HT 1080 cells. From comparative analysis, 85% aq.MeOH fraction showed the strongest scavenging effect on both peroxynitrite in vitro and intracellular ROS in HT 1080 cells. Protective activities of these samples against hydroxyl radical-mediated genomic DNA damage were also investigated. 85% aq.MeOH and n-BuOH fractions significantly inhibited oxidative damage of purified genomic DNA. On the other hand, we investigated their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells. All samples significantly reduced NO production. Among the samples, n-hexane and water solvent fractions most effectively inhibited NO.