• KSBB Journal
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• v.14 no.3
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• pp.358-364
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• 1999

The effect of hydrogen peroxide on pretreatment of oakwood was investigated. Reaction temperature was $170^{\circ}C$ and reaction solutions used in pretreatment were aqueous ammonia, sulfuric acid and pure water. When 10% ammonia solution was used, the extents of delignification and hemicellulose recovery were 55% and 26%, respectively. These values were significantly higher as delinigfication and lower as hemicellulose recovery than those of acid hydrolysis. To overcome this problem, hydrogen peroxide was added into ammonia solution stream to increase hemicellulose recovery. But delignification and hemicellulose recovery were not increased as much as hydrogen peroxide loading was increased. And as hydrogen peroxide loading was increased, the decomposition of sugars solubilized from hemicellulose and cellulose were increased. So there were significant differences between the total amount in solid residue and liquid hydrolyzate, and the total amount in the original biomass. It was found that hydrogen peroxide added was reacted with substrate packed mostly in the front part of reactor. In order to increase hemicellulose recovery, it was necessary to treat with acidic solution than with alkali solution. Effect of hydrogen peroxide was higher in water than acid solution.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.655-662
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• 2013

This study was carried out to investigate the changes in the quality properties of red pepper Yukwa (red pepper liquid fermented with lactic acid bacteria was added to the Yukwa) during the storage period. To determine the shelf life of red pepper Yukwa, the rice Yukwa (control) and red pepper Yukwa were stored at 15, 25, and $35^{\circ}C$ for 70 days. Also, the quality properties of red pepper Yukwa, such as acid value, peroxide value, texture, color, and sensory evaluation were measured. Although the acid value of rice Yukwa and red pepper Yukwa increased during storage, the red pepper Yukwa showed a lower acid value score (1.09mg KOH/g) than that (1.19mg KOH/g) of the rice Yukwa. Nevertheless, these values did not exceed the guideline maximum values of 2.0 g KOH/g specified in the Korean Food Code. The peroxide values of samples had significantly increased after 42 days. Especially, the peroxide value scores for the rice Yukwa and red pepper Yukwa were the highest at 146.49 and 126.79 meq/kg at $35^{\circ}C$, respectively. Hardness and brittleness in textural properties increased up to 70 days. The sensory values for the red pepper Yukwa for overall acceptance, taste;texture and appearance were the highest. The results indicated that by using the 'Visual Shelf life Simulator for foods' of the Korea Food and Drug Administration (KFDA) the shelf life of red pepper Yukwa is estimated to be 274.78 days.

• 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 Nutrition and Health
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• v.20 no.4
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• pp.237-245
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• 1987

Young male rats were fed for 10 and 20 days on different low-fat experimental diets ; 4% lard + 4% soybean oil, 4% sardine oil + 4% lard, 4% sardine oil with vitamin E+ 4% lard, 4% sardine oil with vitamin E+ 4% soybean oil. Lipid peroxide levels in liver were significantly higher in the sardine oil groups but the addition of vitamin Ehad no effects on the lipid peroxide values. Serum total cholesterol showed no significant difference among the groups but HDL-cholesterol in serum was increased in the sardine oil groups. However, the contents of serum triglyceride and phospholipid were unaffected by the replacement with sardine oil.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.169-172
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• 1999

The acivity-guided fractionation on the MeOH extract of Bombycis corpus inoculated by Beauberia bassiana 101A led to the isolation of two steroids, 24-ethycholest-4-ene-3,6-dione (1) ergosterol peroxide (2), as active principles. Compounds 1 and 2 exhibited cytotoxicity against cultured human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT-15 with ED50 values ranging from 3.42 to $11.37{\;}\mu\textrm{g}/m$.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.399-408
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• 2001

Tooth bleaching has been prevailing recently for its ability to recover the color and shape of natural teeth without reduction of tooth material. However, it has been reported that bleaching procedure adversely affects the adhesive bond strength of composite resin to tooth. At the same time the bond strength was reported to be regained by application of some chemical agents. The purpose of this in vitro study was to investigate the effect of the removal of residual peroxide on the composite- enamel adhesion and also evaluated fracture mode between resin and enamel after bleaching. Sixty extracted human anterior and premolars teeth were divided into 5 groups and bleached by combined technique using of office bleaching with 35 % hydrogen peroxide and matrix bleaching with 10% carbamide peroxide for 4 weeks. After bleaching, the labial surfaces of each tooth were treated with catalase, 70% ethyl alcohol, distilled water and filled with composite resin. Shear bond strength was tested and the fractured surfaces were also examined with SEM. Analysis revealed significantly higher bond strength values. (p＜0.05) for catalase-treated specimens, but water-treated specimens showed reduction of bond strength, alcohol- treated specimens had medium value between the two groups(p＜0.05). The fracture mode was shown that the catalase group and the alcohol group had cohesive failure but the water sprayed group had adhesive failure. It was concluded that the peroxide residues in tooth after bleaching seems to be removed by gradual diffusion and the free radical oxygen from peroxide prevents polymerization by combining catalyst in the resin monomer. Therefore it may be possible to eliminate the adverse effect on the adhesion of composite resin to enamel after bleaching by using water displacement solution or dentin bonding agent including it for effective removal of residual peroxide.

• Journal of Biosystems Engineering
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• v.42 no.1
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• pp.62-68
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• 2017

Purpose: The storage life of pearl millet-based, deep fried, ready-to-eat snacks, packaged in aluminum-laminated polyethylene having a thickness of $50{\mu}m$ (with and without nitrogen) was evaluated under storage conditions of $38{\pm}2^{\circ}C$ and 90% RH. Methods: The moisture content, free fatty acids (FFA), peroxide value, and crispness of the snack were evaluated throughout the storage period. The moisture content, FFA, and peroxide value increased with an increase in storage period, but the increase was less in packages flushed with nitrogen gas. The crispness decreased with an increase in the storage period, for snacks both with and without nitrogen packages. However, the decrease was less in nitrogen-flushed packages. FFA and peroxide values were strongly correlated with the moisture content of the snack. The storage life of the snack was found to be 60 and 45 days in packages with and without nitrogen respectively. Conclusions: The snack's predicted storage life, for snacks with and without nitrogen packages, was determined as 294 and 254 days respectively.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.84-89
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• 1999

Treatment with the enzyme pectinase has been reported to lower the cationic demand of thermomechanical pulp(TMP) bleached with alkaline peroxide in the laboratory. We have extended this discovery to bleached TMP produced industrially, and shown that commercial enzyme preparations can treat pulp within 15 minutes at the at the temperature and pH values prevalent in paper mills. About half of the cationic demand in the bleached pulp can be destroyed by pectinase. Dynamic drainage jar experiments show that the enzyme treatment improves the effectiveness of several cationic polymers to increase retention in the absence of retention aids or with non-ionic polymers, and does not damage the strength properties of the pulp. Pectinase could be easily incorporated into paper machine stock preparation systems to lower the charges of cationic retention aids needed in furnishes containing peroxide-bleached mechanical pulp.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.21-27
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• 1981

The effects of anti-oxidant of ether extract of red pepper peel were studied to compare with butylated hydroxyl toluene (BHT), citric acid and ascorbic acid. Peroxide and acid values of magarine irradiated with the sunlight were detected. The results were as follows: 1. The extract of red pepper peel influenced as antioxidant of magarine. But the extract was lower anti-oxidative effect than that of BHT at the same concentrations. The anti-oxidative effect increased with the concentration of the extract applied. 2. There was no synergistic and anti-oxidative effects, when the extract was used together citric and ascorbic acids. 3. The peroxide value of fermented magarine was controlled by the addition of the extract and BHT. However acid value of it was not controlled as much as peroxide value.

• Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.175-178
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• 2006

An acidic ent-cyclic peroxide was isolated from a sponge, Plakotis sp., and showed activity against leishmaniasis and pathogenic fungi. To improve the activity of this compound, we coupled the acidic ent-cyclic at the C1 position of ircinol A. Compound 3 exhibited significant activity against Leishmania mexican a and fungi with $IC_{50}$ values of 0.7 and $0.3-34{\mu}g/mL$, respectively. The yield of compound 3 was 98%.