• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.377-384
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• 2020

Paprika is a popular vegetable with high visual appeal and desirable flavor, the health benefits of which are increasingly attracting interest. In this study, the physical qualities, antioxidant content, and activities of six mini paprika cultivars were investigated. Both the edible part (flesh) and the by-products were studied. The average total phenolics and total antioxidant activities were higher in the flesh than in the by-products. The total flavonoids of the flesh and the byproducts were 16.41 and 37.80 mg/100 g FW, respectively. "YW glory" and "Raon yellow" flesh had the highest (245.52 mg/100 g FW) and lowest (179.96 mg/100 g FW) total phenolics among the six cultivars, respectively. However, the "RD glory" cultivar showed the highest total phenolic content (232.70 mg/100 g FW) among the by-product samples. The total phenolics in the flesh and by-products were highly correlated to the ABTS radical scavenging activity, with R=0.961 and 0.984, respectively.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.451-456
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• 2007

The potential antioxidant activities of methanolic extracts from soybean and rice fermented with Monascus sp. were investigated. M. pilosus IFO 480 and M. anka IFO 478 were screened as a suitable strain to promote the antioxidant activities in soybean- and rice- fermentation. The methanol extracts from soybean and rice after fermenting for 20 days at $30^{\circ}C$ resulted in a significant increase in the antioxidant capacities expressed as radical (ABTS and DPPH) scavenging assay and peroxidation inhibition (%) by thiocyanate method and increased (p<0.01) by a 2.6 to 3.1-fold compared with those of the unfermented products. The average antioxidant potentials of Monascus-fermented soybean extracts (MFSE) were significantly (p<0.01) stronger than Monascus-fermented rice extracts (MFRE). A linear correlations between free radical scavenging activity of MFSE and the total phenolics content (r=0.84) and total flavonoids content (r=0.81) were observed. These results indicated that MFSE exhibited stronger (p<0.01) antioxidant activity and contained significantly higher levels (p<0.05) of phenolics than MFRE.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.143-150
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• 2011

Lactic fermented dongchimi naengmyeun broth which has enhanced antioxidative activity was developed. During lactic fermentation of dongchimi naengmyeun broth at $25^{\circ}C$, changes of total lactic acid bacteria, pH, acidity, soluble phenolics, and anthocyanins were investigated. After 72 h of fermentation, the stronger antioxidant activities were observed in dongchimi naengmyeun broth supplemented with purple sweet potato than those of control dongchimi naengmyeun broth which showing 96.80% in DPPH radical scavenging activity, 100.82% in $ABTs^{+{\cdot}}$ scavenging activity, 7.77 in reducing power, and 6.89 in ferric reducing/antioxidant power, respectively. These high antioxidant activities related with higher contents of soluble phenolics and anthocyanins in dongchimi naengmyeun broth supplemented with purple sweet potato. The results suggest that the making of functional dongchimi naengmyeun broth by using high soluble phenolics and anthocyanins supplements such as purple sweet potato powder was possible.

• The Korean Journal of Food And Nutrition
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• v.34 no.6
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• pp.662-668
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• 2021

Aster koraiensis Nakai (A. koraiensis) which has been used as a food and medicinal plant in the past, is valuable as functional food material. Therefore, the aim of this study was to determine the antioxidant properties and major phenolics of A. koraiensis extracts with different ethanol concentrations (0, 50, 70, and 100% aqueous ethanol solution). When ethanol concentration in the extraction solvent was increased, extraction yield decreased; 34.2, 23.2, 21.0, and 5.5% in 0, 50, 70, and 100% ethanolic extracts, respectively. Total phenolics content and antioxidant activities of extracts were increased in an ethanol concentration-dependant manner. The major phenolics in the extracts were chlorogenic acid (21.264~58.666 mg/g), isochlorogenic acid A (10.432~145.353 mg/g), and isochlorogenic acid C(0.239~13.148 mg/g), and these phenolic contents were higher in 70 and 100% ethanolic extracts than other extracts. Significant correlations were observed between ethanol concentration of extraction solvent, antioxidant properties, and major phenolics. These results indicated that the optimal ethanol concentration for extraction was 70%.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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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.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.37-43
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• 1989

Some phenolics were examined as an antioxidant for the autoxidation of soybean oil. Soybean oil was autoxidized under a mild condition (the flow rate of 67ml $O_{2}/min$ and $50^{\circ}C$). The antioxidant effect was estimated by active oxygen method. Phenolics show distinctive antioxidant effect, and the effect is prominent when cupper or iron was added. Phenolics showed a tendency to increase antioxidant effect with an increase of the number of hydroxyl group, and the increasing order was ferulic acid, quinalizarin, sesamol, alizarin, fisetin and purpurogallin. However, the effect was remarkably low in ferulic acid, alizarin and quinalizarin. It was found that the antioxidant effect was dependent on the functional group and geometric molecular structure of phenolics.

• Nutrition Research and Practice
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• v.8 no.2
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• pp.183-191
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• 2014

BACKGROUND/OBJECTIVES: The objective of this study was to measure and/or estimate the total antioxidant capacity of the Korean diet. MATERIALS/METHODS: Eighty-one plant foods that were expected to exhibit rather high antioxidant activities were selected from the Korean diet using the Fifth Korean National Health and Nutrition Survey (KNHANES V). These foods were categorized into 11 food groups: cereals, potatoes, legumes, nuts, vegetables, kimchies, mushrooms, fruits, fruit juices, sea weeds, and oils. The foods were mixed in the proportions specified in traditional Korean recipes and analyzed. The measured indicators for antioxidant capacities were total phenolics, 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), and Trolox equivalent antioxidant capacity (TEAC). RESULTS: Total phenolics were high in the fruit juices, nuts, vegetables, and fruits; and the average DPPH, ORAC, and TEAC values were high in the vegetables, fruits, fruit juices, and nuts. The correlation coefficient between the content of total phenolics of each food and the in vitro antioxidant capacity was relatively high at 0.851. The intake of total phenolics per capita per day in the Republic of Korea was estimated to be 127 mg. The total dietary antioxidant capacity (TDAC) values, which were obtained from the total antioxidant capacity of each food, taking into account the intake of each food, were 20,763, 54,335, and $876.4{\mu}mol$ of Trolox equivalents using the DPPH, ORAC, and TEAC methods, respectively. The food group that contributed the most to the Korean TDAC was cereals at 39.7%, followed by fruits and vegetables at 27.8% and 13.9%, respectively. The contribution of legumes, nuts, fruit juices, and mushrooms was quite minimal at less than 2% each. CONCLUSIONS: The content of total phenolics and the antioxidant capacity of the Korean diet are significantly correlated and the high contributing food groups are cereals, fruits, and vegetables.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.207-213
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• 2019

This study was conducted to investigate the antioxidant contents and activities of twelve vegetable sprouts (broccoli, red radish, radish, mizuna, kale, taatsai, pak choi, Chinese cabbage, turnip, rapeseed, chicory, and alfalfa). The total flavonoid contents of the broccoli, red radish, and radish sprout were $25.36{\pm}0.13$, $25.26{\pm}1.80$, and $25.16{\pm}1.25mg$ CE/100 g FW, respectively, and were significantly higher than those of the other tested vegetables. Radish sprouts had the highest total phenolic content (112.42 mg GAE/100 g FW), followed by red radish and broccoli sprouts. The main polyphenols in the vegetable sprouts were epicatechin and chlorogenic acid, but they varied across sprout varieties. The correlation between total flavonoids and total phenolics for the 12 vegetable sprouts was very high (r=0.926). The total antioxidant activity (DPPH and ABTS radical scavenging activities) was also highly correlated with total flavonoids and total phenolics.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.700-703
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• 2005

Eight edible mushrooms grown in Korea were extracted with ethanol at room temperature for 24 hr. The extracts were investigated for their antioxidant activities as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activities. Among the mushroom extracts evaluated in this study, the ethanolic extracts from Ganoderma lucidum and Pleurotus eryngii showed the greatest potential antioxidant activity, by producing 85 and 88% inhibition in DPPH radical scavenging method and 219 and 165 mg ascorbic acid equivalent antioxidant capacity (AEAC), respectively. Total phenolics and total flavonoids in the ethanolic extracts were determined by spectrophotometric method. Positive correlations were found between total phenolic contents in the extracts and their antioxidant activities, suggesting that phenolic contents in the mushrooms extracts are mainly responsible for their antioxidant activities.

• Horticultural Science & Technology
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• v.35 no.1
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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.