• Nutrition Research and Practice
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• v.18 no.1
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• pp.33-45
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• 2024

BACKGROUND/OBJECTIVES: Onion, particularly onion peel, is a quercetin-rich food with, anti-inflammatory and immunomodulatory effects. However, the effect of onion peel extract (OPE) in humans is unclear. Thus, the present study aimed to investigate whether OPE improves natural killer (NK) cell activity and cytokine concentration in a randomized double-blind placebo-controlled trial. SUBJECTS/METHODS: Eighty participants aged 19-64 yrs old with a white blood cell count of 4,000-10,000 cells/µL, symptoms of upper respiratory infection at least once within the previous 12 mon, and perceived stress scale (PSS) over 14 were included. Participants were randomly assigned to take either 1,000 mg/day OPE or a placebo for 8 weeks. RESULTS: Compliance were 87.4 ± 8.6% and 86.9 ± 79.0% in OPE and placebo groups. Compared to the placebo, OPE supplementation improved "Hoarseness" (P = 0.038) of the Wisconsin Upper Respiratory Symptom Survey (WURSS)-21 symptom, and stress scores (P = 0.001; 0.021) of PSS. Supplementation of OPE had no significant effect on NK cell activity and concentrations of cytokines such as interleukin (IL)-2, IL-6, IL-12, IL-1β, interferon-γ, and tumor necrosis factor-α. At baseline, the WURSS-21 symptom and PSS score (P = 0.024; 0.026) were higher in the OPE group than the placebo group. Among participants with higher than median WURSS-21 symptom score, OPE supplementation increased NK cell activity (P = 0.038). Supplementation of OPE had no significant effects on safety measurements and adverse events. CONCLUSIONS: The present study suggested that OPE supplementation improves NK cell activity in participants with moderate upper respiratory symptoms without any significant adverse effects.

• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1029-1039
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• 2024

This study explores beneficial bacteria isolated from the roots and rhizosphere soil of Khao Rai Leum Pua Phetchabun rice plants. A total of 315 bacterial isolates (KK001 to KK315) were obtained. Plant growth-promoting traits (phosphate solubilization and indole-3-acetic acid (IAA) production), and antimicrobial activity against three rice pathogens (Curvularia lunata NUF001, Bipolaris oryzae 2464, and Xanthomonas oryzae pv. oryzae) were assessed. KK074 was the most prolific in IAA production, generating 362.6 ± 28.0 ㎍/ml, and KK007 excelled in tricalcium phosphate solubilization, achieving 714.2 ± 12.1 ㎍/ml. In antimicrobial assays using the dual culture method, KK024 and KK281 exhibited strong inhibitory activity against C. lunata, and KK269 was particularly effective against B. oryzae. In the evaluation of antimicrobial metabolite production, KK281 and KK288 exhibited strong antifungal activities in cell-free supernatants. Given the superior performance of KK281, taxonomically identified as Bacillus sp. KK281, it was investigated further. Lipopeptide extracts from KK281 had significant antimicrobial activity against C. lunata and a minimum inhibitory concentration (MIC) of 3.1 mg/ml against X. oryzae pv. oryzae. LC-ESI-MS/MS analysis revealed the presence of surfactin in the lipopeptide extract. The crude extract was non-cytotoxic to the L-929 cell line at tested concentrations. In conclusion, the in vitro plant growth-promoting and disease-controlling attributes of Bacillus sp. KK281 make it a strong candidate for field evaluation to boost plant growth and manage disease in upland rice.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.118-123
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• 2017

This study was conducted to determine the antioxidant activities of ethanol and water extracts of Sargassum hemiphyllum. Antioxidant activities were evaluated by assessing total phenolic contents, 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, chelating effect, reducing power, and using the rancimat method. Total phenolic contents in the ethanol and water extracts were 17.91 and 13.44 mg gallic acid equivalents/g, respectively. Ethanol extract showed higher DPPH radical scavenging activity than water extract and similar activity to that of BHT. The reducing power of ethanol and water extracts increased in a concentration-dependent manner. Particularly, ethanol extract was more effective than water extract. Water extract showed a higher chelating effect compared to ethanol extract. The antioxidant index measured by rancimat was lower than those in BHT, but the ethanol extract showed a higher value than the water extract. The ethanol extract showed higher antioxidant activity than the water extract, except for the chelating effect. These results suggest that the ethanol extract of Sargassum hemiphyllum has more potent antioxidant activity and may be used as a source of natural antioxidants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1086-1095
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• 2013

This study investigated the quality characteristics, oxidative stability, and antioxidative activity of a Korean fried rice cake, Gaeseong-Juak (doughnut of waxy rice) to which Prunus yedoensis Matsumura (PYM) extract, vitamin C, and BHT were added and stored at $60^{\circ}C$ for 4 days. Gaeseong-Juak was prepared by adding PYM extract at 0, 0.5, 1, and 2% of waxy rice powder. It was found that as the content of PYM extract increased, L-values significantly decreased while a-value and b-value significantly increased (P<0.001). The hardness and adhesiveness were increased with an increase in PYM extract, and as the storage period increased. In the sensory evaluations, the sample containing 0.5% and 1.0% PYM extract gave good scores. In the Gaeseong-Juak with PYM extract, the acid value, peroxide value, and p-anisidin value of PYM extract groups were found to have a higher oxidative stability than those of 0% PYM extract group (P<0.05). The antioxidative activity of Gaeseong-Juak to which PYM extract was added increased as the content of PYM extract increased (P<0.001). It was suggested that the shelf life of Gaeseong-Juak could be extended by the use of natural antioxidants, reducing the deterioration of the quality of Gaeseong-Juak.

• The Korea Journal of Herbology
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• v.20 no.2
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• pp.27-33
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• 2005

Objectives : This is the study of the application as the ingredients of cosmetics through the examination of the function for physiological activity of Chestnut inner shell. Methods : Chestnut inner shell, which had been extracted, concentrated, and freeze drying with water and ethanol, have been used for the experiment. The effects on electronic donating ability, SOD-like activity, xanthine oxidase inhibition, whitening effect, nitric oxide inhibition have been investigated in the physiological activity measurement of function experiment. Results : We used BHA and kogic acid for the comparative. As a result of testing electron donating ability, at over 100ppm of water extract and ethanol extract, BHA showed relatively high donating ability by more than 90%. And as a result of measuring SOD like activity, 1000ppm of water extract showed an effect of 30% and ethanol extract showed an effect of 40%, BHA showed an effect of 30%. In the xanthine oxidase inhibition test, 1000ppm of water extract showed an effect of 70% and ethanol extract showed an effect of 63%, BHA showed an effect of 100%. In the tyrosinase inhibition test, 1000ppm of water extract showed an effect of 55% and ethanol extract showed an effect of 87%, Kogic acid showed an effect of 98%. In the anti-inflammatory test, the water extract and ethanol extract inhibited the generation of nitric oxide. Conclusions : The results indicated that extract of Chestnut inner shell can be used as a natural ingredients with biological function in cosmetics ingredients.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.444-448
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• 1993

Flavor compounds of pentane, hexane, hexanal and total volatiles formed during $65^{\circ}C$ storage of ramyon fried in palm oil with ${\alpha}-tocopherol$, RHA, TRHQ, rosemary extract or defatted ricebran extract were determined by static headspace gas chromatography. The levels of the antioxidants used in the frying oil were 100 or 200 ppm, and an additional level of 300 ppm was employed in the case of ${\alpha}-tocopherol$ ${\alpha}-Tocopherol$ decelerated the formation of all the flavor compounds when used at 100 or 200 ppm, and the former was more effective than the latter. However, 300 ppm of ${\alpha}-tocopherol$ accelerated the flavor compound formation in ramyon during storage. One hundred ppm of BHA and TBHQ contributed to the reduction in flavor compound formation in the stored ramyon, whereas 200ppm level accelerated the compound formation. Rosemary extract and defatted ricebran extract lowered the flavor compound formation in ramyon when used at 100 or 200 ppm in palm oil. Their lowering effects were similar to that of ${\alpha}-tocopherol$, and superior to that of TBHQ. suggesting a possible utilization of defatted ricebran extract as a new natural antioxidant.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.432-439
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• 2007

This study was performed to investigate the physicochemical properties and antioxidative activities of water or methanol extracts of Bokbunja (Rubus coreanus), and pork patties containing bokbunja extract at various levels. The total phenolic content of methanol extract (6.76 g/100 g, dry base) was higher than that of water extract (3.38 g/100 g, dry base). In addition, methanol extract had higher 1,1'-diphenyl-2-picrylhdrazyl (DPPH) radical scavenging activity than water extract at low concentrations (0.025-0.1%). However, no significant differences were found at high concentrations (0.2% or higher) (p>0.05). The DPPH radical scavenging activities of methanol and water extracts were 76.97% and 74.87% at 0.2% level, respectively. The lightness and yellowness values of pork patties containing Bokbunja extract decreased with increasing concentrations. The thiobarbituric acid reactive substances (TBARS) in pork patties with Bokbunja extract were lower than that of the control (p<0.05). The antioxidative activities increased with increasing concentrations of Bokbunja extract. In conclusion, Bokbunja extract might be used as a natural antioxidant in meat products, however levels lower than 3% will be required to prevent quality defects in pork patties.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.361-364
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• 2002

This study was performed to establish a simple and accurate method for the determination of oxygen that is a processing aid in various beverage. The quantitative determination of dissolved oxygen (DO) contents in 30 cases of samples were performed by traditional titration method and polarography. As a result of the study, the analysis of DO contents in fruit-extract beverages containing oxygen by titration method was time consuming and large sample volumes were needed. Besides, serious interferences with compounds such as hydroxylamine and nitric oxide were observed, leading to false response. Although the polarography is easily affected by $H_2S$, proteins, and various organic compounds, it is a simple and practical method that provides inexpensive and relatively rapid analysis. The polarography is best suited to the routine determination of DO in a large number of samples and it is expected that the polarography can directly be applied to the quality control of the beverages containing added oxygen. The analysis results of DO contents in various fruit-extract beverages with oxygen and without oxygen were as follows: 23.10 ppm to 32.60 ppm for various frutis extract beverages with oxygen, 0.70 pp to 2.54 ppm for mixed beverages without oxygen, 7.63 ppm to 8.28 ppm for drinking water.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.374-380
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• 2006

In this study, glucose, sucrose, and dextrin were found to be better carbon sources for the production of pullulan by Aureobasidium pullulans HP-2001. Maximal production of pullulan with 200 g/l sucrose as a carbon source was 54.2 g/l. The highest yield of pullulan from sucrose was 0.40, when the sugar concentration was 100 g/1. Optimal conditions for the continuous production of pullulan by A. pullulans HP-2001 in a 7-1 bioreactor were determined by studying the effects of composition of feed solution, dilution rate, and concentration of sucrose in the feed solution. Pullulan concentration and productivity with 100 g/l glucose and 2.5 g/l yeast extract were 38.1 g/l and 0.53 g/l h for 72 h, respectively, in a batch culture of A. pullulans HP-2001. When the substituted medium contained 100 g/l sucrose, 2.5 g/l yeast extract, and mineral salts, which is the same composition as the medium for the production of pullulan, the pullulan concentration and productivity were 74.9 g/l and 0.55 g/l h for 120 h, respectively. The production of pullulan at the steady state increased with a dilution rate up to 0.015/h, and its concentration was 78.4 g/l with a weight average molecular weight ($M_w$) of $4.0{\times}10^5$. Unlike a batch culture, however, the decline of the $M_w$ and the number average molecular weight ($M_n$) of pullulan was not found in the continuous culture of A. pullulans HP-2001. When the concentration of sucrose in the feed solution was 200 g/l, 113.5 g/l of pullulan was obtained at the steady state. The steady state was maintained longer in the continuous culture fed with the feed solution containing 200 g/l sucrose than when fed with the feed solutions containing either 100 or 150 g/l sucrose.

• Journal of dental hygiene science
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• v.13 no.1
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• pp.45-52
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• 2013

Antimicrobial activity of extract from some traditional oriental medicinal plants were evaluated for their antimicrobial activity against six oral pathogens, Streptococcus salivarius, Streptococcus oralis, Streptococcus mutans, Streptococcus sanguinis, Lactobacillus acidophilus and Lactobacillus casei, which are associated with caries disease. The antimicrobial activity was examined by determining the inhibition zone using the disc diffusion assay. In antibacterial activity test, extracts of Scutellaria baicalensis, Chrysanthemum indicum, Kochia scoparia, Hydnocarpus anthelmintica and Caesalpinia sappan showed inhibitory effects (40 mg/ml) against tested caries bacteria. Especially, the C. sappan extract showed the strongest activity on S. oralis (40 mm), L. casei (35 mm) and S. mutans (28 mm). Thus, this result suggests that C. sappan may be applicable to preventing dental caries.