• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.199-205
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• 2004

The effect of chitosan on enzymatic activities and on bioactive compounds was characterized during germination at $25^{\circ}C$ for 7 days to search for a method to produce a germinated black rice. The germination rate was reduced by the addition of lactate and chitosan. The rotting rate was greatly decreased by chitosan, suggesting that the addition of chitosan into a germination solution might be an effective method for controlling fungal contamination during the germination of cereals. The addition of 100 and 200 ppm chitosan increased $\alpha$-amylase activity after 7 days by up to 152 % and 197 %, respectively. The activities of $\beta$-amylase and $\beta$-glucosidase were lower with 200 ppm chitosan than in distilled water and 100 ppm lactate. The amount of total soluble phenolics and total flavonoids decreased rapidly for four days and thereafter remained constant until the seventh day. The antioxidant activity of germinated black rice, in terms of hydrogen-donating activity, increased slowly and did not correspond to the changes of total soluble phenolics and total flavonoids. The amount of phytic acid was reduced by the addition of 200 ppm chitosan compared to distilled water, indicating that chitosan could be used as an elicitor for the increase of phytase activity during the germination of black rice.

• 미생물학회지
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• 제47권2호
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• pp.143-150
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• 2011

기능성이 밝혀져 있는 자색고구마를 첨가하여 기호성과 영양뿐만 아니라 인체에 유익한 기능성 동치미 냉면육수 개발을 위한 연구를 수행하였다. 자색고구마를 첨가한 동치미 냉면육수 발효 과정에서 젖산균, pH, 산도, 유기산, 수용성 phenolics, anthocyanin, 및 항산화 활성 변화를 조사하였다. 특히, 자색고구마를 첨가한 경우 발효종기(72시간)에 수용성 phenolics 및 anthocyanins 함량은 각각 1.26 g/L 및 8.59 g/L로 대조실험과 비교하여 각각 5배 및 34배 높았다. DPPH 라디칼 소거 활성 96.80%, $ABTs^{+{\cdot}}$ 라디칼 소거활성 100.82%, 환원력 7.77 ($OD_{700}$), FRAP 6.89 ($OD_{593}$)로 대조실험과 비교하여 각각 4배, 1.2배, 2배 및 3.6배 높은 항산화 활성을 나타내었다. 이상의 결과로부터 동치미 냉면육수의 항산화 활성은 자색고구마의 수용성 phenolics와 anthocyanins과 밀접한 관련이 있는 것으로 판단되었으며, 항산화 활성이 증가된 기능성 동치미 냉면육수 제조가 가능하였다.

• Preventive Nutrition and Food Science
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• 제15권1호
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• pp.36-43
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• 2010

The purpose of this study was to investigate the phenolic acid, proanthocyanidin (PAs), and flavonol glycoside contents, as well as the antioxidant activities of pine needle extracts from six species of young pine trees. The extracts were prepared from Section Pinus (Diploxylon): P. densiflora, P. sylvestris, P. pinaster and P. pinea, and Section Strobus (Haploxylon): P. koraiensis and P. strobus. Phenolics were extracted from pine needles with 80% acetone to obtain the soluble free fraction, and insoluble residues were digested with 4 M NaOH to obtain bound ethyl acetate and bound water fractions. Phenolics were analyzed by HPLC, and the hydrophilic antioxidant activity was measured using oxygen radical absorbance capacity (ORAC). Total phenolic and flavonoid contents of the soluble free fraction were higher than those of the bound ethyl acetate and bound water fractions. The main phenolics were monomers and polymers of PAs in the soluble free fraction, and phenolic acids and flavonol glycosides in bound ethyl acetate fraction. Flavonol glycosides found in different species of pine needles were qualitatively similar within fractions, but composition varied among Pinus sections. High levels of kaempferol arabinoside and an unknown compound were present in all Strobus species. The soluble free fraction had the highest antioxidant activity, followed by bound ethyl acetate and bound water fractions.

• 한국식품저장유통학회지
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• 제13권6호
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• pp.732-739
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• 2006

볶음처리한 새송이버섯의 마이크로웨이브 추출조건, 즉 에탄올 농도, 추출시간 및 마이크로웨이브 power에 따른 품질특성을 살펴보았다. 총 페놀성 화합물 함량, 전자공여능 및 pH 1.2에서의 아질산염소거능은 50% 에탄올로 추출한 경우 높게 나타났다. SOD 유사활성은 75% 에탄을 농도로 추출하였을때 가장 높은 활성을 나타났다. 가용성 고형분 및 총 페놀성 화합물 함량은 추출시간이 증가할수록 증가하다가 7분일 때 가장 높게 나타났으며, 전자공여능은 추출시간이 증가할수록 감소하는 것으로 나타났으며, SOD유사활성 및 아질산염소거능의 경우추출시간에 따른 유의적인 차이가 없는 것으로 나타났다. 마이크로웨이브 power 의 경우 100 W로 추출하였을 때 가용성 고형분, 총 페놀성화합물 함량 및 전자공여능 가장 높게 나타났다. SOD 유사 활성은 25 W일 때 높은 활성을 나타내었다. 그러나 아질산염 소거능은 마이크로웨이브 power에 영향을 많이 받지 않는 것으로 나타났다.

• Current Research on Agriculture and Life Sciences
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• 제28권
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• pp.53-62
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• 2010

원적외선 조사가 포도씨 기능성분의 변화에 미치는 영향을 알아보고자 가열출력(0, 900, 1800 W) 및 가열시간(0, 20, 40 min)을 달리하여 원적외선 조사 후 마이크로파를 이용하여 포도씨 추출물을 제조하고 기능성분으로서 가용성 고형분, 기계적 색도, 카테킨, 총 페놀, 총 플라보노이드 함량 및 전자공여능과 아질산염 소거능을 각각 측정하였다. 가용성 고형분 함량 및 백색도 및 적색도는 유의적인 차이가 없는 것으로 나타났다. Cathechin류는 가열시간에 따라 catechin, procyanidin $B_2$, epicatechin 함량의 변화가 있음을 확인하였으며, 총 catechin 함량은 총 카테킨 함량은 900 W 및 20분 처리 시 가장 높게 나타났다. 총 페놀성화합물 및 플라보노이드 함량 또한 가열출력 900W 및 가열시간 20분 일 때 가장 높게 나타났다. 그에 따라 전자공여능도 가열출력 900 W 및 가열시간 20분 일 때 가장 높은 것으로 나타났다. 이상의 결과는 원적외선 처리에 의해 총 페놀성 화합물 함량, 총 플라보노이드 함량이 증가됨을 볼 수 있었으며, 특히 cathechin류의 변화가 있음을 확인할 수 있었다. 또한 이로 인해 항산화능도 증가됨을 알 수 있었다. 또한 포도씨의 원적외선 가열처리 최적조건을 설정하고자 가열출력 및 가열시간을 달리하여 중심합성실험계획으로 반응표면분석한 결과 가열출력 621.82~818.18 W, 가열시간 16.3~19.83 min의 범위가 최적 가열조건범위로 설정되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1591-1602
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• 2019

Objective: The present study was conducted to evaluate the antioxidant potential of paneer, a soft cheese supplemented with various water soluble date extracts during storage. Further, the whey obtained from all the paneer samples was also investigated for its antioxidant potential. Methods: The date cultivars were evaluated for their physico-chemical characteristics and date extracts were assessed for their antioxidant potential. Physico-chemical evaluation, microbiological quality and further antioxidant potential of the prepared paneer were carried out during storage period (0 to 8 days, $5^{\circ}C$). Results: All the date extracts were found to have considerable antioxidant activity due to presence of total phenolics and flavonoids. Owing to the presence of phenolics and flavoinds in date extracts, supplemented paneer showed higher trolox equivalent antioxidant capacity, reducing power and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than control paneer. Paneer supplemented with Rabi extracts had the highest total phenolics ($190.7{\mu}g$ gallic acid equivalent/g paneer), DPPH radical scavenging activity ($928.1{\mu}mol$ equivalent of Trolx/g paneer) and trolox equivalent antioxidant capacity ($9.2{\mu}mol$ equivalent of Trolx/g paneer). The whey obtained from control paneer showed lower values of total phenolics, total flavonoids, DPPH, trolox equivalent antioxidant capacity and reducing power as compared to the values of whey obtained from paneer supplemented with date extracts. Conclusion: Paneer supplemented with date extracts and its whey may offer potent antioxidant activity.

• 원예과학기술지
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• 제35권1호
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• pp.88-97
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• 2017

This study explored the physicochemical and nutritional changes associated with storage duration of fresh tomatoes. Fruits of the 'TY Megaton' and 'Yureka' tomato cultivars were harvested at the pink stage and stored at $12^{\circ}C$ for 20 days. During storage, firmness, weight loss, skin color (Hunter L, a, b, a / b values), soluble solids content (SSC), titratable acidity (TA), pH, antioxidant contents (lycopene, ascorbic acid, and total phenolics) and antioxidant activity were evaluated. Firmness was above the minimum marketable limit and fresh weight loss was below maximum acceptable weight loss after 3 weeks of storage, and no deleterious effect on antioxidant contents or activities were observed. Significant differences in SSC, TA, and pH were seen between varieties, but not between fruits stored for different durations. In both varieties, Hunter a values increased more than five-fold after 8 days of storage; this correlated with a more than four-fold accumulation of lycopene after two weeks of storage. The antioxidant activity of tomatoes was highest at the beginning of the storage period, likely because of the effective DPPH - reducing power of ascorbic acid and total phenolics. Antioxidant activity increased after 12 days of storage because of increasing lycopene content. Hence, this study indicates that pink - stage tomatoes may be stored at $12^{\circ}C$ for up to 3 weeks without affecting marketability or nutritional value.

• Preventive Nutrition and Food Science
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• 제14권1호
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• pp.43-48
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• 2009

Current study investigated phytochemical compositions and antioxidant capacity of Korean leafy vegetables including chajogi, gomchwi, meowi and sseumbagwi. ${\beta}$-carotene, total soluble polyphenol, total flavonoids contents were determined, and antioxidant capacity were evaluated by various methods. ${\beta}$-carotene, total soluble polyphenol, total flavonoids contents in gomchwi were significantly higher (as much as 19 folds) compare to other vegetables (p<0.05). Sseumbagwi extract ($100{\mu}g/mL$) was removed 78.6% of superoxide radicals in xanthin-xanthin oxidase system measured by EPR. Gomchwi showed the highest nitrate scavenging activity as 94.3% at pH 1.2. In SOD-like activity, chajogi, gomchwi, and meowi were evaluated in the range of $12.6{\sim}24.5%$. All samples were revealed to prevent the reaction of ferrous chloride during 9 days, which were comparable ability with 125 mg/100 g of ${\alpha}$-tocopherol. The rich phytochemical contents of gomchwi and sseumbagwi influenced to high antioxidant capacity.

• Food Science and Biotechnology
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• 제16권5호
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• pp.740-746
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• 2007

Fruit juices such as grape juice are associated with healthy products by consumers because of the many health benefits they provide. Farm produced (FPGJ) and commercially produced grape juice (CPGJ) in South Korea were compared and studied through the evaluation of their physicochemical, functional, and sensory properties. The results of this study show that FPGJ's physicochemical properties are more varied than CPGJ. The pH, titratable acidity, and total soluble solids of FPGJ were higher than CPGJ. FPGJ had a higher mean value for total phenolics ($2,558.20{\pm}50.06\;mg/L$ GAE), total flavonoid ($3,236.80{\pm}56.11\;mg/L$), total anthocyanin ($559.88{\pm}3.51\;mg/L$), and radical scavenging activity (86.48%) than CPGJ, although the differences were significant only with regard to total flavonoid and total anthocyanin. This study also demonstrates that CPGJ is preferred in terms of sensory evaluation. These properties may be used as a basis for the optimization of processing to produce a higher quality grape juice.

• Food Science and Biotechnology
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• 제18권4호
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• pp.996-1000
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• 2009

Sapium japonicum was extracted by a pressurized liquid. Operating parameters such as the type and the ratio of solvent to water, temperature, pressure, and number of extractions were investigated as the main variables that influence the extraction efficiencies of total phenolics (TP). MeOH extracted the highest level of TP as 50.4 mg GAE/g compared to 48.8 and 27.2 mg GAE/g with $H_2O$ and EtOH, respectively. $EtOH:H_2O$ (40:60, v/v) was found to be the best solvent for TP extraction as 90.3 mg GAE/g compared to 85.0 and 84.3 mg GAE/g in 40:60 and 60:40 of $MeOH:H_2O$, respectively. TP were increased with the increase of the number of extraction steps. TP content was increased by 11% as the extraction temperature was increased from 40 (97.4) to $50{\circ}C$ (108.3 mg GAE/g). The optimum extraction conditions of TP were; extraction solvent, $EtOH:H_2O$ (40:60, v/v); temperature, $50{\circ}C$; pressure, 10.2 MPa; 2 extraction steps.