• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.27-34
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• 2008

This study investigated the anti-hypertensive effect of Phyllostachys pubescens culm extract (PCE) by examining its effects on renal angiotensin-converting enzyme (ACE) inhibition and blood pressure using the spontaneously hypertensive rat (SHR) system. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured weekly for 8 weeks. Also, total antioxidant capacity and protein oxidation of tissues were examined by plasma Trolox Equivalent Antioxidant Capacity assay (TEAC) and hepatic protein carbonyl values, respectively. Twenty male SHR were randomly divided into four groups: PCE50, PCE100, and PCE500 (50, 100, and 500 mg of PCE per kilogram bodyweight daily, respectively), and control group. At week 2, the SBP in all PCE groups appeared to be significantly lower than the control (p<0.05), whereas the DBP were not different until week 4 (p<0.05). At week 8, SBP in the PCE500 was lower by 20% than the control. PCE groups considerably suppressed ACE dose-dependently compared with the control. Plasma TEAC and hepatic protein carbonyl values indicated increased antioxidative activity due to the PCE feed. No adverse effect was observed on the liver of SHR as there was no difference for the GOT and GPT values among the groups. Results of this study suggest that ACE inhibition may be one possible mechanism for the blood pressure lowering effect of PCE; thus, long term consumption of PCE may be beneficial in preventing high blood pressure along with the increased antioxidative status.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1660-1665
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• 2015

Oats (Avena sativa L.) were evaluated in recent years as a promising crop for increasing the nutritional quality of foods, due to their abundance in many bioactive compounds. The objectives of this study were to determine antioxidant compounds and antioxidant activities of nine oat cultivars and investigate the relationships between antioxidant compounds and antioxidant activities in oat cultivars. The contents of total polyphenolics and vitamin E in oat cultivars were analyzed by spectrophotometric methods and normal phase HPLC, respectively. 2,2'-Azino-bis-(3-ethylbenzothiazoline- 6-sulphonic acid) (ABTS) radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities, reducing power, and chelating effects were used to compare the relative antioxidant activities of oat cultivars. In this study, total polyphenolic and vitamin E contents of oat cultivars ranged from 83.41 to 130.59 mg gallic acid equivalents/100 g and 0.54 to 1.90 mg/100 g, respectively. High levels of ABTS radical (116.14 mg Trolox equivalent antioxidant capacity (TEAC)/100 g) and DPPH radical (38.58 mg TEAC/100 g) scavenging activities and reducing power ($A_{700}=0.922$) were found in Daeyang. Significant correlation was evaluated between total polyphenolic contents and their antioxidant activities, namely ABTS and DPPH radical scavenging activities and reducing power. A low correlation was observed between vitamin E contents and their antioxidant activities. The results of this study could have an impact on oat consumption by enhancing consumer awareness of the health benefits of oats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.519-525
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• 2012

Effects of cultivated conditions on antioxidant compounds and antioxidant activities of sweet potatoes (Ipomoea batatas (L.) Lam) were determined. The cultivated variety was Shinyulmi, and they were cultivated in a conventional culture, successful cropped hairy vetch culture, successful cropped barley cultivation, successful cropped rye cultivation, successful cropped mix-seeding of hairy vetch and barley, successful cropped mix-seeding of hairy vetch and rye, and not fertilizer. The brix degree, moisture, protein, and ash content of the sweet potatoes did not significantly change with the cultivated conditions. However amylose, total dietary fiber, and mineral content had significant changes. The total polyphenol, flavonoid, and tannin content of the methanolic extracts of the sweet potato's pericarp showed significant differences from cultivated conditions, however, the sweet potato's sarcocarp did not significantly change. The highest DPPH and ABTS radical scavenging activities of the methanolic extracts of the sweet potatoes were 958.81 and 663.53 mg TE/100 g in the sweet potato's pericarp on the successful cropped hairy vetch culture. Generally, there was a difference in antioxidant compound content and radical scavenging activity on the methanolic extract of sweet potato with cultivated conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.269-275
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• 2008

The avocado is a widely grown and consumed fruit that is high in nutrients and low in calories, sodium, and fats. In this study, antioxidant activities and induction of apoptosis by methanol extracts from sarcocarp, seed and peel of avocado were investigated in vitro. Contents of total polyphenols in methanol extracts from sarcocarp, seed and peel were 13.89, 137.12 and $223.45{\mu}g/mg$ respectively. Radical-scavenging activities of the methanol extracts were examined by using ${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) radicals and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay. The methanol extracts from the peel of avocado showed higher scavenging activities against DPPH, ABTS than those from sarcocarp and seed. Apoptosis in MDA-MB-231 cells mediated by the methanol extracts of avocado was associated with the increase of activation of caspase-3 and caspase-3 target protein, PARP. Therefore, with more researches on identification and action mechanism of active compounds, the methanol extracts from peel and seed of avocado is expected to be a natural source for the developments of functional food and medical agents to prevent human breast cancer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1370-1377
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• 2013

Rice is widely grown in Asia and is one of the major dietary staples in the world. Also, rice contains antioxidants which can prevent from oxidative stress related diseases, including cancer, atherosclerosis, and diabetes. Because the rice is consumed cooked, the effect of the cooking process on the antioxidative and antigenotoxic properties of rice is lacking. The aim of this study was to determine the effects of cooking on the antioxidant and antigenotoxic effects of white rice (WR), brown rice (BR), and germinated brown rice (GBR). The antioxidant activities were measured for total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total antioxidant capacity (TRAP), and oxygen radical absorbance capacity (ORAC). The highest TPC was found in uncooked BR (18.4 mg gallic acid equivalent/100 g). After cooking, the TPC of WR significantly increased, while the TPC of BR and GBR were reduced by 47.7% and 36.7%, respectively. The $IC_{50}$ for DPPH RSA was not significantly different in uncooked rice, while the DPPH RSA of WR and GBR decreased after cooking and the DPPH RSA of BR significantly increased. TRAP values in BR and GBR increased after cooking, while the value of WR decreased. The ORAC values of uncooked WR, BR, and GBR were 5.3, 4.3, and $3.9{\mu}M$ trolox equivalent at the concentration of $50{\mu}g/mL$. After cooking, the ORAC value of BR remained unchanged, while the value of GBR increased and the value of WR decreased. The antigenotoxic activities of WR, BR, and GBR were determined by measuring the inhibitory effects of $H_2O_2$-induced DNA damage on human leukocytes using the comet assay. The results showed that all rice tested showed a significant antigenotoxic effect against oxidative stress, except for the cooked white rice. Overall, our results indicate the addition of brown rice and/or germinated brown rice to cooked white rice is a good option for improving the benefits of rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1316-1326
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• 2017

We evaluated the proximate compositions of raw materials, total polyphenols, total flavonoids, and radical scavenging activities of roasted maize tea according to cultivation period and variety. Proximate compositions of raw materials were significantly different according to cultivation period and variety, and quality characteristics of roasted maize tea extracts were significantly different according to cultivation period. Total polyphenols, total flavonoids, and radical scavenging activities of roasted maize tea were significantly different before and after roasting. The total polyphenol content of Pyeonggangok cultivar sown on April 5th was elevated about 3.60-fold before and after roasting by $3.42{\pm}0.16$ and $12.22{\pm}0.67mg$ gallic acid equivalents/g, respectively. Overall, total polyphenol content was higher in roasted maize tea produced using maize sown on April 5th. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity of Gangdaok cultivar sown on April 5th was elevated about 31.6-fold before and after roasting by $7.61{\pm}1.93$ and $240.37{\pm}8.82mg$ Trolox equivalents (TE)/g, respectively. 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity of Pyeonggangok cultivar sown on April 5th was elevated about 5.5-fold before and after roasting by $153.84{\pm}1.32$ and $843.54{\pm}3.64mg$ TE/g, respectively. The correlation between proximate compositions of raw materials and quality as well as antioxidant characteristics of roasted maize tea showed overall significance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.352-360
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• 2017

This study evaluated the quality characteristics, polyphenolic compounds, and radical scavenging activity of cooked-rice added to commercially available mixed grains. L-value of cooked-rice with various mixed grains decreased compared to that of cooked-white rice; however, a- and b-values increased. Hardness and elasticity of cooked-rice added to various mixed grains were significantly lower in the pressure cooker compared to the electric cooker. There was no significant difference in adhesiveness and stickiness between rice from the electric cooker and pressure cooker. Total polyphenol and flavonoid contents of cooked-rice added to various mixed grains were significantly increased. The average total polyphenol content of cooked-rice added to various mixed grains cooked in an electric cooker and pressure cooker were $16.50{\pm}3.86$ and $15.88{\pm}3.52mg$ gallic acid equivalent /100 g, and flavonoid contents were $1.58{\pm}0.00$ and $1.55{\pm}0.02mg$ catechin equivalents/100 g, respectively. The average of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity was $9.27{\pm}2.62$ and $8.72{\pm}2.41mg$ trolox equivalent (TE)/100 g, and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity was $22.89{\pm}4.60$ and $23.07{\pm}4.49mg$ TE/100 g for cooked-rice added to various mixed grains cooked in an electric cooker and pressure cooker, respectively. Phenol content and radical scavenging activity of cooked rice was in proportion to the amount of added grains, such as brown rice, colored rice, barley, soybean, and sorghum.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.480-485
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• 2019

The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

• Journal of Life Science
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• v.31 no.7
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• pp.617-625
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• 2021

To enhance the applications of apple pomace, which is a by-product of apple, this study analyzed the nutritional components, ursolic acid content, and antioxidant activity of different solvent (distilled water, fermented alcohol, and methanol) extracts. The samples included hot air-dried and freeze-dried apple pomace. The moisture, protein, fat, ash, and total dietary fiber contents of hot air-dried apple pomace were 3.2%, 3.9%, 2.4%, 2.0%, and 28.5%, respectively, and those of freeze-dried apple pomace were 8.2%, 3.4%, 2.4%, 1.8%, and 33.0%, respectively. Ursolic acid was not detected in the distilled water extract of either sample. However, in hot air-dried apple pomace, the methanol extract was 1,753.32 ㎍/ml, and the fermented alcohol extract was 1,532.94 ㎍/ml. In freeze-dried apple pomace, the methanol extract was 1,407.04 ㎍/ml, and the fermented alcohol extract was 1,221.81 ㎍/ml. The total polyphenol and flavonoid contents were 306.7 ㎍/ml and 950.1 ㎍/ml, respectively in methanol extracts of hot air-dried apple pomace and 277.6 ㎍/ml and 925.0 ㎍/ml, respectively in methanol extracts of freeze-dried apple pomace. 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities of hot air-dried apple pomace were 73.3% in methanol extract and 59.4% in fermented alcohol extract, and those of freeze-dried apple pomace were 76.1% in methanol extract and 66.0% in fermented alcohol extract. Both samples had the lowest antioxidant activity in distilled water extracts. Similar to DPPH radical scavenging activity, both samples showed increasing 2,2'-azino-bis(3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) radical scavenging activity in the order of methanol, fermented alcohol, and distilled water. All samples had stronger reducing power than ascorbic acid (311.5 ㎍/ ml) as a positive control.

• The Korean Journal of Food And Nutrition
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• v.36 no.5
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• pp.379-386
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• 2023

The objective of this study was to investigate the distribution of functional compounds in perilla leaves of various genetic resources and their antioxidant activities. A comprehensive analysis of functional compounds was conducted for 90 genetic resources, focusing on total polyphenol content (TPC), total flavonoid content (TFC), individual phenolic content (IPC), and lutein. Their antioxidant activities were then analyzed based on their radical scavenging capacity using ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl). The TPC content exhibited a range of 13.19 to 35.85 mg gallic acid equivalent/g, whereas the TFC content varied from 11.74 to 46.51 mg catechin equivalent/g. Total IPC was detected in a range of 6,310.98 to 40,491.82 ㎍/g. Lutein was detected at levels between 70.97 and 597.97 ㎍/g. ABTS and DPPH radical scavenging activities of perilla leaves ranged from 30.39 to 58.58 mg trolox equivalent (TE)/g and from 7.74 to 46.56 mg TE/g, respectively. Furthermore, correlation analysis demonstrated that rosmarinic acid, a phenolic acid, exhibited a significantly positive correlation with antioxidant activity. These findings suggest that various genetic resource of perilla leaves could effectively mediate antioxidant capacity. Results of this study provide valuable information for use of perilla leaves in Korea as functional food materials.