• Korean journal of food and cookery science
• /
• v.21 no.1 s.85
• /
• pp.94-102
• /
• 2005

The purpose of this study was to investigate the antioxidative effect and quality characteristics of cookies made with Lycii fructus powder(LFP). The cookies were stored at $50^{\circ}C$ for 40 days. The LFP additive increased the moisture, ash, crude protein and volume of the cookies. When LFP was added at $5\%$ into the cookies, the spread ratio was higher than for the control, the $10\%$ and the $20\%$ LFP cookies. As more LFP was added, the L-value decreased, and the a--values and b-values increased for the color values. For the textural characteristics, springiness and cohesiveness of the control cookies were the highest among the samples, the other side, brittleness and gumminess were higher in cookies made with LFP than in the control cookies. Overall, the cookies made with $5\%$ LFP were preferred more than the other cookies, as tested forby sensory evaluation. The cookies made with LFP contained mostly palmitic acid (C16:0) followed by oleic acid (C18: 1) and stearic acid (C18:0). The acid value, peroxide value, and thiobarbituric acid value were lower in cookies made with $5\%$ and $10\%$ LFP than in those cookies made with $20\%$ LFP and the control cookies.

• Journal of the Korean Chemical Society
• /
• v.14 no.3
• /
• pp.213-219
• /
• 1970

In the presence of hydrogen peroxide, the effects of temperature and pH to the catalytic reaction velocity of cupric -thiocyanate and the quantities of reduction products adsorbed on the D.M.E. have been studied by polarographic method. According to these experiments, the following empirical equation has been derived for the relation among temperature $T_i$, concentration of hydrogen ion $pH_i$ and adsorbed cuprous-thiocyanate in moles/$cm^2Z_{ij}$, and rate constant log$K_{ij}$ $$log\;K_{ij}=\frac{1}{T_i}\{A(pH_j)+B\}+C(pH_j)+D$$ $$Z_{ij}=\frac{1}{T_i}\{{\alpha}(pH_j)^{\frac{1}{2}}+{\beta}\}+{\gamma}(pH_j)^{\frac{1}{2}}+{\delta}$$ where, A,B,C,D and {$\alpha},{\beta},{\gamma},{\delta}$ are constants. The Calculated values by both equations are well agreed with empirical values within 8% in the error.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.9
• /
• pp.2657-2662
• /
• 2013

Multiwalled carbon nanotube (MWCNT)-g-poly (aniline-co-2,5-diaminobenzenesulfonic acid) (DABSA) reinforced Nafion$^{(R)}$ nanocomposite membranes were prepared and characterized for direct methanol fuel cells (DMFCs). The nanocomposite membranes with approximately $90{\mu}m$ thickness were prepared by the water assisted solution casting method. To evaluate the properties of nanocomposite membranes for DMFC applications, the nanocomposite membranes were characterized by methanol and water uptake, thermal stability, and ion exchange capacity (IEC). Furthermore, oxidative stability measurements in terms of the hydrogen peroxide decomposition rate that represent the oxidative stability of the membranes were examined. The methanol uptake values of the nanocomposite membranes were dramatically decreased compared to the cast Nafion$^{(R)}$ membranes. The IEC values of the nanocomposite membranes were increased about 30% compared to the cast Nafion$^{(R)}$ membrane.

• Restorative Dentistry and Endodontics
• /
• v.34 no.2
• /
• pp.154-161
• /
• 2009

This clinical study evaluated the whitening effect and safety of polymer based-pen type BlancTis Forte (NIBEC) containing 8.3% carbamide peroxide. Twenty volunteers used the BlancTis Forte whitening agent for 2 hours twice a day for 4 weeks. As a control. Whitening Effect Pen (LG) containing 3% hydrogen peroxide was used by 20 volunteers using the same protocol. The change in shade (${\Delta}E^*$, color difference) was measured using $Shadepilot^{TM}$ (DeguDent) before, during, and after bleaching (2 weeks, 4 weeks, and post-bleaching 4 weeks). A clinical examination for any side effects (tooth hypersensitivity or soft tissue complications) was also performed at each check-up. The following results were obtained. 1. Both the experimental and control groups displayed a noticeable change in shade (${\Delta}E$) of over 2. No significant differences were found between the two groups (p > 0.05), implying that the two agents have a similar whitening effect.2. The whitening effect was mainly due to changes in a and b values rather than in L value (brightness). The experimental group showed a significantly higher change in b value, thus yellow shade, than the control (p < 0.05). 3. None of the participants complained of tooth hypersensitivity or soft tissue complications, confirming the safety of both whitening agents.

• Safety and Health at Work
• /
• v.5 no.2
• /
• pp.91-96
• /
• 2014

Background: Chronic obstructive pulmonary disease (COPD) is an important cause of occupational mortality in miners exposed to coal mine dust. Although the inflammatory mediators involved in COPD have not been defined, many studies have shown that inflammatory mediators such as reactive oxygen and nitrogen species are involved in orchestrating the complex inflammatory process in COPD. Methods: To investigate the relevance of exhaled biomarkers of oxidative and nitrosative stress in participants with COPD, we determined the levels of hydrogen peroxide, malondialdehyde (MDA), and 3-nitrotyrosine (3-NT) in exhaled breath condensate (EBC) in 90 retired elderly coal miners (53 non-COPD and 37 COPD participants). Results: Mean levels of MDA (4.64 nMvs. 6.46 nM, p = 0.005) and 3-NT (3.51 nMvs. 5.50 nM, p = 0.039) in EBC were significantly higher in participants with COPD. The median level of MDA did show statistical difference among the COPD severities (p = 0.017), and the area under the receiver operating characteristic curve forMDA (0.67) for the diagnostic discrimination of COPD indicated the biomarker. The optimal cutoff values were 5.34 nM (64.9% sensitivity and 64.2% specificity) and 5.58 nM (62.2% sensitivity and 62.3% specificity) forMDA and 3-NT, respectively. The results suggest that high levels ofMDA and 3-NT in EBC are associated with COPD in retired elderly miners. Conclusion: These results showed that the elevated levels of EBC MDA and EBC 3-NT in individuals with COPD are biomarkers of oxidative or nitrosative stress.

• Food Science of Animal Resources
• /
• v.21 no.1
• /
• pp.1-9
• /
• 2001

This study was carried out to investigate the extraction yield, the contents of total phenol substances and antioxidative substances, electron donating abilities, nitrite scavenging abilities of water and ethanol extracts from Cassia tora L. and Pueraria thunbergiana and antioxidative activity of water and ethoanol extract from Cassia tara L. Tatal phenol substances of water and ethanol extract from Cassia tora L. and Pueraria thunbergiana showed nearly the same levels, and the antioxidative substances of water and ethanol extract from Pueraria thunbergiana has as much as two times higher than those from Cassia tara L.. The nitrite scavenging abilities were measured at pH 1.2, 3.0, 4.2 and 6.0, respectively. Water and ethanol extracts from Cassia tora L showed 14.9%∼22.3% and 49.1%∼56.7%, and those from Pueraria thunbergiana revealed 57.7%∼61.0% of nitrite scavenging abilities, respectively. Especially the extracts from Pueraria thunbergiana showed higher pH dependence than those from Cassia tora L. The electrol donating abilities of water extract from Cassia tora L. were higher than those from Pueraria thunbergiana, and vice versa in the case of ethanol extracts. In the antioxidative activitiy of extracts from Cassia tora L. against linoleic acid during storage of 20 days at 50$^{circ}C$, peroxide values at the addition level of 5mg and 10mg were consoderably lower than 2mg although peroxide value increased above 375 after 12days of storage compared with the control(BHA-added) of 129 at 8days.

• Mycobiology
• /
• v.51 no.4
• /
• pp.246-255
• /
• 2023

Genus Penicillium comprising the most important and extensively studied fungi has been well-known as a rich source of secondary metabolites. Our study aimed to analyze and investigate biological activities, including in vitro anti-cancer, anti-inflammatory and anti-diabetic properties, of metabolites from a marine-derived fungus belonging to P. levitum. The chemical compounds in the culture broth of P. levitum strain N33.2 were extracted with ethyl acetate. Followingly, chemical analysis of the extract leaded to the isolation of three ergostane-type steroid components, namely cerevisterol (1), ergosterol peroxide (2), and (3β,5α,22E)-ergosta-6,8(14),22-triene-3,5-diol (3). Among these, (3) was the most potent cytotoxic against human cancer cell lines Hep-G2, A549 and MCF-7 with IC₅₀ values of 2.89, 18.51, and 16.47 ㎍/mL, respectively, while the compound (1) showed no significant effect against tested cancer cells. Anti-inflammatory properties of purified compounds were evaluated based on NO-production in LPS-induced murine RAW264.7 macrophages. As a result, tested compounds performed diverse inhibitory effects on NO production by the macrophages, with the most significant inhibition rate of 81.37±1.35% at 25 ㎍/mL by the compound (2). Interestingly, compounds (2) and (3) exhibited inhibitory activities against pancreatic lipase and α-glucosidase enzymes in vitro assays. Our study brought out new data concerning the chemical properties and biological activities of isolated steroids from a P. levitum fungus.

• Food Science and Biotechnology
• /
• v.17 no.5
• /
• pp.971-975
• /
• 2008

This study was to examine the potential disinfection efficiencies of 10 compounds by determining their antimicrobial capacity and ichthyotoxicity. Antimicrobial effects against Vibrio sp., Edwadsiella tarda, Streptococcus sp., and Staphylococcus sp. were tested using 10 different disinfectants; hydrogen peroxide, sodium hypochlorite, chlorine dioxide, povidon iodine, formaldehyde, glutaraldehyde, quaternary ammonium compounds (QACs), didecyl dimethyl ammonium chloride (DDAC), ortho-dichlorobenzen, and copper sulfate. Chlorine dioxide ($ClO_2$) containing 5% $ClO_2$ and copper sulfate had no effects on bactericidal activity, while the other disinfectants resulted in 99.99% bactericidal activity against 4 strains of fish pathogenic bacteria. The ichthyotoxicity of the 10 disinfectants was investigated using 3 kinds of fish species; flounder (Paralichthys olivaceus), rockfish (Sebastes pachycephalus), and black sea bream (Acanthopagrus schlegelii). Median lethal concentration ($LC_{50}$) values of the 10 disinfectants were estimated to determine toxicity ranges of the doses within 24 hr. Among test disinfectant solutions, hydrogen peroxide showed the highest $LC_50$ in flounder (201.3), rockfish (269.7), and black sea bream (139.3 ppm). DDAC revealed the lowest $LC_{50}$ in flounder (2.1), rockfish (1.0), and black sea bream (1.5 ppm). These results suggest that DDAC, quaternary ammonium compounds, glutaraldehyde, and sodium hypochlorite are effective disinfectants for fish and bacterial species examined in this study.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.2
• /
• pp.287-294
• /
• 2013

Influence of Achyranthes japonica Nakai Extract (AJNE) on properties of pork sausages were studied in the present investigation. AJNE was added to sausages alone or in combination with ascorbic acid to obtain a comparative analysis on properties of control and ascorbic acid added-sausages. Results showed that addition of 0.05% AJNE led to a decrease in color $L^*$ and whiteness (W), and an increase in color $b^*$ of pork sausage samples (p<0.05). Although color $a^*$ of pork sausages containing AJNE was not significantly different, ascorbic acid added-sausages were highest amongst other treatments (p<0.05). Sausages containing AJNE had lower non-heme iron values and peroxide value (POV) than control sausages (p<0.05); however, high nitrosomyoglobin content was observed in AJNE added-sausages (p<0.05). Ascorbic acid led to a decrease in residual nitrite concentration of sausages (p<0.05), but no difference was found in AJNE added-sausages. Free radical scavenging analysis showed that AJNE did not affect 1,1-diphenyl -2-picrylhydrazyl (DPPH) activity of sausages, whereas ascorbic acid added-sausages showed relatively higher activity among the samples (p<0.05). Addition of AJNE had no influence on texture properties of sausages. In sensory evaluation, AJNE treatment had significant effects on color (p<0.05), but no significant effects on aroma, flavor, springiness, juiciness, and overall acceptability. In conclusion, the addition of AJNE, as a natural supplement may offer natural antioxidants for pork sausages, and appears to be particularly effective in inducing changes in non-heme iron concentration, POV value and nitrosomyglobin content.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.4
• /
• pp.603-608
• /
• 1998

Lipid oxidation in ascidian was studied when fresh, deshelled and sliced meats were fermented for 50 days at 5$\pm$2$^{\circ}C$ with 8%(w/w) salt and 0.1% papain. Antioxidative effects of butylated hydroxytoluene(BHT) and carotenoid extracts from ascidian tunic on lipid oxidation and oxidationrelated discoloration of ascidian meat during fermentation were investigated. Changes in peroxide value, carbonyl value, thiobarbituric acid value, fatty acids composition, the loss of total carotenoid and sensory evaluation were determined to assess the rancidity. Peroxide and carbonyl values in BHT and carotenoid extract treatments increased less than those of the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control but it increased slowly until 40 days in cases of 0.02% BHT or 0.02% BHT with 0.05% carotenoid added. Fatty acids of fresh ascidian composed of polyenoic acid, saturated acid and monoenoic acid of 51.5%, 28.1% and 20.7%, respectively. Saturated fatty acids(C16:0, C14:0, C18:0) and monoenoic acids(C18:1, C16:1) increased while polyenoic acids(C20:5, C22:6) decreased during fermentation. Carotenoid was markedly degraded and discolored in the control during fermentation. But 0.02% BHT and 0.05% carotenoid treatments had bright color like fresh meat during 40 days. The results of sensory evaluation during the fermentation also convinced the retard of discoloration by the addition of BHT and carotenoid.