• 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.

• Applied Chemistry for Engineering
• /
• v.21 no.1
• /
• pp.63-70
• /
• 2010

Transition metal based spent catalysts (Ni-Mo and Co-Mo), which were scrapped from the petrochemical industry, were reused for the removal processes of volatile organic compounds (VOCs). Especially the optimum regeneration procedures were determined using the removal efficiency of VOCs. In this work, the spent Ni-Mo and spent Co-Mo catalysts were pretreated with different physic-chemical treatment procedure: 1) acid aqueous solution, 2) alkali solution, 3) chemical agent and 4) steam. The various characterization methods of spent and its regenerated catalysts were performed using nitrogen adsorption, X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with an energy dispersive spectrometry (EDS). It was found that all spent catalysts were found to be potentially applicable catalysts for catalytic oxidation of benzene. The experimental results also indicated that among the employed physico-chemical pretreatment methods, the oxalic acid aqueous (0.1 N, $C_2H_2O_4$) pretreatment appeared to be the most efficient in increasing the catalytic activity, although the catalytic activity of spent Ni-Mo and spent Co-Mo catalysts in the oxidation of benzene were greatly dependent on the pretreatment conditions. The pretreated spent catalysts at optimum condition could be also applied for removing other aromatic compounds (Toluene/Xylene).

• Applied Chemistry for Engineering
• /
• v.19 no.6
• /
• pp.668-673
• /
• 2008

The objective of this study is to optimize the leaching conditions of sequential leaching and extracting processes for selective Ni recovery from spent Ni-Mo-based catalyst. The selective Ni recovery process consists of two processes of leaching and extracting process. In this 2-step process, Ni component is dissolved from solid spent Ni-Mo-based catalyst into leaching agent in leaching process and sequentially extracted to Ni complex with an extracting agent in the extracting process. The solutions of nitric acid ($HNO_3$), ammonium carbonate ($(NH_4)_2CO_3$) and sodium carbonate ($Na_2CO_3$) were used as a leaching agent in leaching process and oxalic acid was used as an extracting agent in extracting process. $HNO_3$ solution is the most efficient leaching agent among the various leaching agent. Also, the optimized leaching conditions for the efficient and selective Ni recovery were the leaching temperature of $90^{\circ}C,\;HNO_3$ concentration of 6.25 vol% and elapsed time of 3 h. As a result, Nickel oxalate having the highest yield of 88.7% and purity of 100% was obtained after sequentially leaching and extracting processes under the optimized leaching conditions.

• Korean Journal of Food Science and Technology
• /
• v.6 no.3
• /
• pp.147-157
• /
• 1974

This study was undertaken to observe the effect of sesame in the diet of rats (Splague Dowley). Comparisons were made of weight gains, organ weights and the cholesterol, phospholipid and triglyceride content of the blood serum and liver tissue. Rats weighing 67-80 g were used for the study, while rats weighing 160-165 g were used in the study. In the both studies, the experimental animals were fed on sesame mixtures for 24 weeks. The study was conducted to determine the effect of sesame hulls which are known to contain a high proportion of oxalic acid and phytic acid, which are toxic substances causing various physical disorders. The rats were divided into four groups, a control group which was fed on a standard diet and three groups fed with 20%, 10% and 5% mixtures of sesame seed hulls respectively. The study was designed to observe the same effect, but in this case the rats were divided into two groups, one fed with a 5% mixture of whole sesame seeds and the other with a 5% mixture of dehulled seeds. The results are as follows: 1) An examination of weight gains showed that group I and II which were fed on 20% and 10% mixture of sesame hulls were significantly retarded in comparison with the control group(P<0. 05). 2) Comparisons of organ weights, group I (20% mixture) showed relatively lower weights(P<0.05). 3) The cholesterol content of the blood serum and liver tissue of group I (20% mixture) and group II (10% mixture) were significantly higher than that of the control. 4) The group fed on the whole sesame seed diet and that fed on the dehulled seed diet differed significantly from each other. 5) With the results stated above, the investigators could observe that a high content of sesame hulls in the diet caused retardation in growth and might be the cause of many physical disorders. Though these effects are not important in Korea at present, the increasing intake of sesame seeds and oils indicates that it may become an important problems.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
• /
• 2003.10a
• /
• pp.154-154
• /
• 2003

국내산 홍화씨를 부위별(Whole, Coat and Endosperm)로 분리한 후 추출용매, 볶음조건, 효소가수분해 등의 처리조건을 달리하여 추출된 추출물의 이화학적특성과 기능성성분 함량을 분석, 비교하였다. 홍화씨 부위별추출물의 고형분함량은 60%에탄올배유부분추출물이 11.29%로, 19$0^{\circ}C$, 30분 볶음처리배유추출물이 14.53%로, amyloglucosidase 처리배유추출물이 24.21%로 높은 고형분이 추출되었다. 총페놀함량은 추출용매의 에탄올농도가 증가함에 따라 증가하는 경향이었고, 80% 에탄올점질추출물이 965mg%로 가장 높았으며, 21$0^{\circ}C$, 30분 볶음처리껍질추출물이 756 mg%로, celluase처리껍질추출물이 1170mg%로 높은 함량이었다. 총플라보노이드함량은 80%에탄올전체추출물이 317 mg%로, 21$0^{\circ}C$, 30분 볶음 처리배유추출물이 488 mg%로, $\beta$-amylase 처리전체추출물이 554 mg%로 높은 함량이었다. 유리당 중 sucrose함량은 21$0^{\circ}C$, 10분 볶음처리배유추출물이 123.4 mg%로, 60%에탄올배유추출물이 57.0 mg%로, Celluase 처리배유추출물이 67.1 mg%로 가장 높은 함량이었고, 또한 glucose, fructose, xylose 및 arabinose 등도 함유하고 있었다. 유기산 중 citric acid 함량은 20%n 에탄올배유추출물이 243.3 67.1 mg%로, 21$0^{\circ}C$, 30분 볶음처리전체추출물이 76.3 mg%로, amyloglucosidase 처리배유추출물이 699.3 mg%로 가장 높은 함량이었고, 또한, oxalic, malic, succinic, acetic 및 fumaric acid 등도 확인되었다. Serotonin 화합물 중 serotonin- I 함량은 100% 에탄올껍질추출물이 431 mg%로, 21$0^{\circ}C$, 10분 볶음처리껍질추출물이 192 mg%로, amyloglucosidase 처리껍질추출물이 256 mg%로 가장 많았다. 또한, Serotonin-II함량은 100%에탄올껍질추출물이 763 mg%로, 17$0^{\circ}C$, 10분 볶음처리전체추출물이 312 mg%로, amyloglucosidase 처리껍질추출물이 456 mg%로 가장 많았다. Acacetin 함량은 80%에탄올배유추출물이 34.9 mg%로, 21$0^{\circ}C$, 30분 볶음처리배유추출물이 221.0 mg%로, amyloglucosidase 처리배유추출물이 27.8 mg%로 가장 많았다.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.5
• /
• pp.568-572
• /
• 1999

Coating with chitosan ($2\%$, pH: 5.0) had a beneficial effect such as less weight loss, flesh firmness and maintenance of sugar content of tomatoes stored at the normal temperature. The weight loss of chitosan-coated tomatoes was $4.8\%$ during the storage-period (18days) while that of control was $10.2\%$. When it was stored for 18 days, the tomatoes coated with chitosan showed higher in firmness (1.63 kg) and pectin content ($0,58g\%$) than the control (1.03 kg, $0.44g\%$). For the total soluble acid and pH, the tomatoes coated with chitosan were higher in oxalic acid ($0.17 g\%$) than the control ($0.15 g\%$) and the latter were higher in the pH than the former, when they were stored for 18 days.

• Resources Recycling
• /
• v.13 no.5
• /
• pp.37-44
• /
• 2004

In this study, neodymium oxalate powders were prepared by injecting oxalic acid to the neodymium chloride solution resulted from the acid leaching solution of NdFeB magnet scrap. The effect of experimental conditions on the characteristics of neodymium oxalate powders were investigated. Neodymium oxalate was aggregated by primary particles formed by nucleation, and average size of aggregates was affected by experimental conditions. In a constant volume, increase of reactants affected the average size of aggregate formed by collision of primary particles. In a constant concentration of reactants, agitation speed decreased the size of aggregate due to breakage of particles attached on the surface of aggregate. The number of primary particles decreased with increasing reaction temperature, and the size of aggregates decreased due to the decrease of collision probability. From the results of decomposition behavior of neodymium oxalate, oxalate decomposed from $400^{\circ}C$, and neodymium oxide began to crystallize at above $620^{\circ}C$.

• Korean Journal of Food Science and Technology
• /
• v.42 no.3
• /
• pp.298-303
• /
• 2010

This study was carried out to compare the physicochemical characteristics of Korean traditional wine fermented from foxtail millet and nuruk at different mixing rates. The alcohol contents of fermented wine ranged from 12.70 to 13.38%. Two kinds of commercial nuruks, SH and BS nuruk, were used. The brix degrees of foxtail millet wine fermented by SH and BS nuruks were 21.6 and $22.4^{\circ}Bx$, respectively. The pH, total acidity, and turbidity of the wines fermented by SH and BS nuruks were 3.74 and 3.40, 1.40 and 1.51%, and 0.441 and 0.149, respectively. With an increase in the amount of foxtail millet, brix degree, pH, turbidity, b-value and L-value decreased, and total acidity and a-value increased. Total color difference (${\Delta}Eab$) parameter of the wine fermented by SH nuruk were 8.58, 22.59 and 22.55, while those by BS nuruk were 0.35, 4.08 and 7.16 in 30, 70 and 100% addition rates of foxtail millet, respectively. With an increase in the amount added of foxtail millet, glucose content decreased. The organic acids such as lactic acid and acetic acid were predominantly detected in the fermented wine. Finally, based on sensory evaluations, the wine fermented by BS nuruk showed the best overall quality at the 30% addition rate of foxtail millet.

• Journal of the East Asian Society of Dietary Life
• /
• v.26 no.1
• /
• pp.88-98
• /
• 2016

The pharmacological effects of ginseng berry have been known to improve psychological function, immune activities, cardiovascular conditions, and certain cancers. It is also known that fermentation improves the bioavailability of human beneficial natural materials. Accordingly, we investigated the optimal fermentation conditions of ginseng berry extract with strain isolated from conventional foods. We also analyzed the fermentation product and its antioxidant activity. The bacterium isolated from fermented kimchi was identified as Lactobacillus sp. strain KYH. To optimize the process, fermentation was performed in a 5 L fermenter containing 3 L of ginseng berry extract at 200 rpm for 72 hr. Under optimized conditions, batch and fed-batch fermentations were performed. After fermentation, organic acids, amino acids, sugars, ginsenosides, and antioxidant activity were evaluated. The optimum fermentation conditions were determined as pH 7.0 and a temperature of $30^{\circ}C$, respectively. After fermentation, the amounts and compositions of organic acids, amino acids, sugars, ginsenosides, and antioxidant activity were altered. In comparing the distribution of ginsenosides with that before fermentation, the ginsenoside Re was a major product. However, amounts of ginsenosides Rb1, Rc, and Rd were reduced, whereas amounts of ginsenosides Rh1 and Rh2 increased. Total phenol content increased to 43.8%, whereas flavonoid content decreased to 19.8%. The DPPH radical scavenging activity and total antioxidant activity increased to 27.2 and 19.4%, respectively.

• Analytical Science and Technology
• /
• v.12 no.4
• /
• pp.290-298
• /
• 1999

A study on the application of impedance phase angle for redox titration, acid-base titration, chelate titration and precipitation titration has been carried out. A constant alternating current was passed between two platinum electrodes. One of them was a polarizable micro-electrode of $0.1cm^2$ or $0.026cm^2$ surface area and the other a non-polarizable large electrode of $1cm^2$ surface area dipped in the solution to be titrated. The impedance and the phase angle of the titration cell were measured with lock-in amplifier to obtain well behaved titration curve respectively. In titration of oxalic acid vs. potassium permanganate, the end-point was obtained successfully from the phase angle titration curve. In this experiment, the concentration of 0.0005 M to 0.05 M, the current of $50{\mu}A$ and the frequency of near 50 Hz were used. In titration of phosphoric acid vs. sodium hydroxide, the first end-point was obtained successfully on the optimum experimental condition of 0.001 M concentration, $50{\mu}A$ current and 25~97 Hz frequency. However, the end-point in titration of cupric sulfate vs. disodium-EDTA couldn't be obtained clearly. The end-point was obtained with the out-of-phase impedance curve on the experimental condition of 0.01 M concentration, $100{\mu}A$ current, 5~35 Hz frequency range. In titration of sodium chloride vs. silver nitrate, the end-point was obtained successfully on the experimental condition of 0.1 M concentration, $100{\mu}A$ current and 5~47 Hz frequency range. This study showed that the impedance phase angle was applicable for the detection of the end-points in redox titration curve, acid-base titration curve, chelate titration curve and precipitation titration curve.