• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.515-525
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• 2023

This research aimed to examine the effects of grapefruit seed extract (GSE) at various concentrations on the microbial safety and physicochemical characteristics of onion puree (0.01~0.1%). The onion puree was kept at 4℃ for 14 days. The results of the study indicated that the addition of GSE did not cause any significant changes in the sample's brix degree and viscosity in onion puree (p<0.05). However, as the concentration of GSE increased, the pH level decreased. On the other hand, as GSE was added, the lightness of the onion puree increased, while the redness and yellowness decreased. Compared to pure onion puree, the GSE-incorporated onion puree had higher levels of total flavonoid and total polyphenol content, indicating that it helps to maintain antioxidant activities. Based on the microbial safety test, aerobic bacteria, yeast, and mold were absent until day 14 of storage. In conclusion, the study suggests that the addition of GSE to onion puree increases its antioxidant activity and shelf-life.

• Food Science and Preservation
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• v.16 no.1
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• pp.82-86
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• 2009

By analysis of pyruvic acid and sugar levels in bulbs, leaf sheaths, and leaves, and with regard to phyllotaxis, it was shown that the lower portion of each plant component had the greatest pyruvic acid content, the upper portion less, and the middle portion the lowest. When bulb scales were examined, pyruvic acid content was lowest in the second bulb scale from the papery scale. Pyruvic acid level increased toward the inner portion of the bulb. Pyruvic acid levels in leaf sheaths and leaves were greater than those in the bulb during the early stages of bulb growth. However, at harvest, the pyruvic acid content of bulbs increased slightly, whereas those of leaf sheaths and leaves decreased markedly. Tissue sugar contents were similar at the beginning of bulb growth. However, bulb sugar content increased greatly as the bulb grew, and sugar contents of leaf sheaths and leaves decreased. With respect to phyllotaxis, outer older leaves had the lowest total sugar and pyruvic acid contents. Young leaves showed a tendency to have less pyruvic acid and sugar compared with mature leaves.

• The Plant Pathology Journal
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• v.39 no.6
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• pp.600-613
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• 2023

Fusarium oxysporum is the main pathogen causing Fusarium basal rot in onion (Allium cepa L.), which incurs significant yield losses before and after harvest. Among management strategies, biological control is an environmentally safe and sustainable alternative to chemical control. In this study, we isolated and screened bacteria for antifungal activity against the basal rot pathogen F. oxysporum. Isolates 23-045, 23-046, 23-052, 23-055, and 23-056 significantly inhibited F. oxysporum mycelial growth and conidial germination. Isolates 23-045, 23-046, 23-052, and 23-056 suppressed the development of Fusarium basal rot in both onion seedlings and bulbs in pot and spray inoculation assays. Isolate 23-055 was effective in onion seedlings but exhibited weak inhibitory effect on onion bulbs. Based on analyses of the 16S rRNA and rpoB gene sequences together with morphological analysis, isolates 23-045, 23-046, 23-052, and 23-055 were identified as Bacillus thuringiensis, and isolate 23-056 as Bacillus toyonensis. All five bacterial isolates exhibited cellulolytic, proteolytic, and phosphate-solubilizing activity, which may contribute to their antagonistic activity against onion basal rot disease. Taken together B. thuringiensis 23-045, 23-046, 23-052, and 23-055 and B. toyonensis 23-056 have potential for the biological control of Fusarium basal rot in onion.

• 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.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.41-47
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• 2000

This study was conducted to evaluate development of seed pellet technique such as pellet polymer search, the shape formation and hardness, the germination and emergence rate of the pellet seeds for labor-saving and reducing production cost in onion(Allium cepa L.) cultivation. The pellet seeds shape formation was good such as kaolin, clay, ash, and gypsum, and clay was good shape formation but surface of pellet seed was cracked during the drying. PG(pearlite + gypsum) as pellet material and PVA as binder were the best among the material in consideration with shape and hardness together. The hardness of the pellet seeds was affected by polymers, the kinds and concentration of binders, and that degree was large at polymer. The high hardness polymers were gypsum and coal ash, but burned lime was the lowest hardness among the pellet material. The germination(GP) and emergence percentage(EP) of pellet seed with PG in vitro were the highest among the material, and that was 93.6, 91.8%, respectively. The EP of pellet seed with PG at 20, $25^{\circ}C$ were 91.3, 92.0%, respectively, The EP of pellet seed were over the 91%, and those did not show difference with field moisture capacity , and that of 5 and 6mm size seed were the highest as 92%, respectively. and other size seeds showed over 90%, too. The EP of pellet seed with PG was decreasing as increasing the sowing depth, and that of at 10mm sowing depth was the highest as 92.7%. The time to 50% emergence of that under 70% field moisture capacity was 158h, and that was delayed at 20h compare to control seed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.4
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• pp.223-231
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• 2017

This study was conducted to determine the impact of elevated temperature based on climate change scenario on growth and bulb quality of extremely early-maturing onion (Allium cepa L. cv. Singsingball) in the temperature gradient tunnels. There were treated with 3 groups, one is a control group (ambient temperature, mean temperature at $9.8^{\circ}C$), another ambient temperature $+2^{\circ}C$ (mean temperature at $12.0^{\circ}C$), and the other ambient temperature $+5^{\circ}C$ (mean temperature at $14.3^{\circ}C$). Compared with the control, plant height, neck diameter, leaf area, top fresh weight and dry weight were significantly increased at ambient $+2^{\circ}C$ temperature. Bulb diameter and bulb weight was highest at ambient $+2^{\circ}C$ temperature (mean temperature at $12.0^{\circ}C$) during the growth period. Bulb/neck diameter ratio, over 2.0 a good indicator of development of bulb, increased rapidly at ambient $+2^{\circ}C$ temperature. This result suggests that extremely early-maturing onion (Allium cepa L. cv. Singsingball) could maintain the higher productivity and bulb quality at ambient $+2^{\circ}C$ temperature. On the contrary, $5^{\circ}C$ higher than atmospheric temperature shows negative effects on yields under a future climate change scenario.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.88-89
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• 2011

• Food Industry And Nutrition
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• v.12 no.2
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• pp.44-50
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• 2007

양파(노란색, 붉은색, 흰색)의 열수 추출물이 DNCB로 감작된 4주령 BALB/c mouse 암컷에 유도된 접촉성 피부염의 억제효과를 조사하였다. 림프절, 비장 및 흉선의 무게는 양파 투여군이 DNCB 대조군보다는 낮게 나타났다. 양파 추출물을 투여한 군에서 귀의 무게는 양파 추출물의 농도가 높을수록 감소하는 경향을 보였으며, 대조군과 비교하여 무게에 함량 변화가 있었다. 양파추출물을 1,000 mg/kg 농도로 투여하면 귀의 무게는 대조군과 유사한 수준까지 낮아졌으며, 귀의 두께는 양파추출물을 투여한 군에서 시간이 경과할수록 두께가 감소하는 경향을 나타내었다. MDA 함량은 DNCB대조군과 양파 투여군을 비교하였을 경우에, 간 조직에서 차이가 나타나지 않았으나, 염증이 발생한 귀 조직에서는 차이가 나타났으며, NO 함량은 모든 양파그룹에서 염증이 억제되어 대조군에 유사하게 측정되었다.

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.195-196
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• 2012

• Food Science and Preservation
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• v.18 no.6
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• pp.954-960
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• 2011

The antioxidant activities of the ethanol, methanol, and water extracts of black onion were investigated. The highest extraction yield (28.56%) and total polyphenol content (13.5 mg/g) were found in the water extract. The water extract also showed the highest protective effect on the RAW 264.7 cell anti-inflammatory activity, and the water and ethanol extracts showed the highest reducing power. The water extract showed higher DPPH and ABTS radical scavenging activities (65.98 and 89.69%, respectively) than the other solvent extracts (ethanol, 47.77%; methanol, 66.12%). Hence, black onion can be used as a potent natural antioxidative source.