• The Korean Journal of Food And Nutrition
• /
• v.37 no.3
• /
• pp.152-161
• /
• 2024

This study investigated the influence of incorporating chestnut inner shell powder (CISP) at varying levels (0%, 3%, 6%, 9%, and 12% w/w) on the quality, antioxidant potential, and consumer preference of garaetteok, a Korean rice cake. Findings revealed a decrease in moisture content and pH with increasing CISP content. Color analysis indicated a reduction in lightness (L) and yellowness (b) values, while redness (a) values increased. Textural properties displayed an increase in hardness, chewiness, and gumminess, but a decrease in springiness, adhesiveness, and cohesiveness with increasing CISP levels. Sensory evaluation for appearance, taste, flavor, texture, and overall preference revealed the sample containing 6% CISP to be the most favorable. Moreover, the antioxidant activity of the garaetteok exhibited a positive correlation with increasing CISP content. In conclusion, incorporating 6% CISP resulted in improved quality characteristics for garaetteok development, offering enhanced nutritional value, antioxidant properties, and overall consumer preference.

• Journal of the East Asian Society of Dietary Life
• /
• v.21 no.6
• /
• pp.838-843
• /
• 2011

The objective of this study is to evaluate antioxidant activities of Rehmanniae Radix Preparata (RRP) prepared from dried root through nine repeated steaming-drying cycles. The total phenolic content of the final cycle of RRP increased to 165.2% compared with that of the 1st cycling product. Antioxidant activities which were determined by ferric-reducing antioxidant potential (FRAP), 2,2'-azinobis(3 ethybenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picrydrazyl (DPPH), and hydroxyl radical scavenging activities, increased remarkably as the number of steaming-drying cycles increased. Especially, FRAP value increased to 89.1%. Further, $IC_{50}$ values for DPPH and hydroxyl radical scavenging activities of the final 9th-cycling product decreased to 58.3% and 67%, respectively. Based on these results, it was observed that the antioxidant activities of RRP improve according to an increased number of steaming-drying cycles.

• Preventive Nutrition and Food Science
• /
• v.22 no.3
• /
• pp.216-222
• /
• 2017

Antioxidant rich green leafy vegetables including garden spinach leaf, water spinach leaf, Indian spinach leaf, and green leaved amaranth were selected to evaluate the effects of water boiling and oil frying on their total phenolic content (TPC), total flavonoid content (TFC), reducing power (RP), and antioxidant capacity. The results revealed that there was a significant increase in TPC, TFC, and RP in all the selected vegetables indicating the effectiveness of the cooking process on the antioxidant potential of leafy vegetables. Both cooking processes enhanced significantly (P<0.05) the radical scavenging ability, especially the oil fried samples showed the highest values. There is a significant reduction in the vitamin C content in all the vegetables due to boiling and frying except in the Indian spinach leaf. However, the present findings suggest that boiling and frying can be used to enhance the antioxidant ability, by increasing the bioaccessibility of health-promoting constituents from the four vegetables investigated in this study.

• Food Science and Biotechnology
• /
• v.17 no.5
• /
• pp.1086-1091
• /
• 2008

The antioxidant activities of the extracts of dangyuja (Citrus grandis Osbeck) leaves were evaluated. The highest phenolic content was obtained from the ethyl acetate fraction (EF) (202.1$\pm$0.8 mg GAE/g dried extract) and it exhibited the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. The cytoprotective effects of EF on oxidative damage induced by tert-butyl hydroperoxide (t-BHP) in a human hepatoma cell line, HepG2 cells, were investigated to understand the intracellular antioxidant mechanisms. Treatment of HepG2 cells with EF prior to oxidative stress was found to inhibit reactive oxygen species (ROS) generation, lipid peroxidation, and DNA damage in a dose-dependent manner. Gas chromatography-mass spectrometry (GC-MS) studies on EF resulted in tentative identification of 19 compounds representing 94.3% of the total content. Taken together, these results demonstrated that EF has excellent antioxidant activities and thus dangyuja leaves have great potential as a source for natural antioxidant which can be applied in food products.

• Korean Journal of Medicinal Crop Science
• /
• v.19 no.5
• /
• pp.341-346
• /
• 2011

The objective of this study was to evaluate antioxidant activities of Rehmannia glutinosa (Raw Jihwang) by traditional method. The total phenol content of Rehmannia radix Preparata (the final cycle of Jihwang) was increased to 205%, compared with Rehmannia glutinosa. Antioxidant activities, determined by ferric-reducing antioxidant potential (FRAP), 2,2'-azinobis(3 ethybenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, 1,1-diphenyl-2-picrydrazyl (DPPH) and hydroxyl radical scavenging activities, increased remarkably as the number of steaming-drying cycles increased. Especially, FRAP value increased 285%. Also, $IC_{50}$ values for DPPH and hydroxyl radical scavenging activities of the final 9th-cycling product, decreased 48.4% and 76%, respectively, compared with those of Rehmannia glutinosa. Our result was suggested that antioxidant activities of Rehmannia radix Preparata improve according to the increasing number of steaming-drying cycles.

• Journal of Applied Biological Chemistry
• /
• v.60 no.1
• /
• pp.35-39
• /
• 2017

Turkey has a very rich fungal flora due to its phytogeographical position. The screening of chemical content and active substances of mushrooms becomes an important subject not only for Turkey but also for all over the world. In the last decade, Analyses on phytochemical and biological activity of fungi have gradually increased as a result of improvement in the number and quality of facilities. In the scope of the present research, four medicinal mushrooms; Morchella elata, Lactarius volemus, Cantharellus cibarius and Tricholoma terreum were analyzed for their fatty acid compositions and antioxidant capacities. The fungal species have been found with unsaturated fatty acid/saturated fatty acid ratio of 6.73 for Morchella elata, 4.12 for Lactarius volemus, 5.21 for Cantharellus cibarius, 3.73 for Tricholama terrum. In addition, the concentration of malondialdehyde which was an indicator of lipid peroxidation was also determined in these species. According to the results, free radical scavenging activity of Morchella elata and Lactarius volemus were found higher than the other species. Any of the mushroom species investigated were found having very high metal chelating activity. The results showed that the extract of Morchella elata and Lactarius volemus exhibited significant antioxidant activities. Hence, the mushrooms have a potential to be a natural antioxidant in food industries as antioxidant agent.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.63 no.3
• /
• pp.219-228
• /
• 2018

Weedy rice (Oryza sativa) is a semi-wild rice grown in paddy fields and is more adapted to the environment than cultivated rice. Therefore, it is expected that the seeds of weedy rice might contain some chemicals related to its environmental adaptation, such as antioxidants, which may be useful for nutritional and medicinal purposes. This study was carried out to investigate the antioxidant activities of weedy rice compared to a Korean-bred rice cultivar, Sindongjin (SDJ), and to screen lines that show higher antioxidant activity in 199 accessions of weedy rice germplasm collected in Korea. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity ranged from 31.0 to 91.7%, with an average of 82.5%, and 19 accessions that showed more than 91% antioxidant activity were selected. The 19 accessions were re-screened against non-germinated brown rice (BR) and germinated brown rice (GBR) using four assays, total phenol determination, DPPH radical scavenging, ABTS radical scavenging, and reducing power activities. The results showed that accession 'WD3' had the highest antioxidant capacity in both BR and GBR, suggesting that WD3 is a promising potential source of antioxidants and could be developed as a potentially functional substance material.

• Korean Journal of Medicinal Crop Science
• /
• v.21 no.3
• /
• pp.191-196
• /
• 2013

The effect on the antioxidant activity and Nitric Oxide activity production inhibitory activity of Taraxacum has not been known. Therefore, phenolics and flavonoid contents were investigated from the ethanol extracts of five different Taraxacum species. The results showed that, among the five Taraxacum, T. hallaisanensis contains the highest total phenolic and flavonoid contents. When the antioxidant activity was measured by DPPH, $ABTS^+$ and reducing power activity, the free radical scavenging activity of T. hallaisanensis was also the highest among five Taraxacum species. However, measurement by CCK-8 assay in Raw264.7 cells indicated that the extracts of Taraxacum species have no effect on cell viability. Moreover, we also investigated the effect of Taraxacum species on NO scavenging activity in lipopolysaccharide (LPS)-stimulated Raw264.7 cells. The results clearly showed that Taraxacum species inhibited NO production, and the inhibitory effect of T. hallaisanensis was the strongest. The above results suggested that Taraxacum species affected the antioxidant and NO scavenging activity, and among the five species, antioxidant and NO scavenging activity assay of T. hallaisanensis was significantly higher than those of other four Taraxacum species. Therefore, T. hallaisanensis could be used as a potential drug with anti-oxidant and anti-inflammatory effect.

• KSBB Journal
• /
• v.23 no.1
• /
• pp.96-100
• /
• 2008

In this work, we describes analysis of the antioxidant potential of Korean green tea phenolics using an high-performance liquid chromatography (HPLC) on-line $ABTS^{+}$ antioxidant screening method. In conjunction with the analysis of their 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) radical scavenging ability, the extraction of catechine compounds from Korean green tea were performed by various temperature and time. The optimum operating conditions were experimentally determined to analyze the catechine compounds in the pretreatment extracts. From the results, the extraction temperature $60^{\circ}C$, time 3 min was selected as an optimal antioxidant activity condition. The analysis by $C_{18}$ column was performed, the flow rate of mobile phase and UV wavelength was fixed at 1.0 ml/min and 254 nm, respectively. the mobile phase was composed from acetonitrile and water, and the gradient elution mode were applied.

• Korean journal of food and cookery science
• /
• v.28 no.3
• /
• pp.311-318
• /
• 2012

The correlation between osteoporosis and reactive oxygen species (ROS)-induced oxidative stress was investigated. Thus, interest in food and plants with antioxidant effects that can reduce damage caused by ROS during bone metabolism is heightening. In this study, the antioxidant effect of Taraxacum mongolicum on proliferation and differentiation of MC3T3-E1 cells under H2O2-induced oxidative stress was studied to investigate its protective effect against oxidative stress and its availability as an antioxidant material related to bone diseases. As a result, total polyphenol and total flavonoid contents of T. mongolicum were 33.65 mg/g and 4.45 mg/g, respectively. The T. mongolicum extract increased proliferation of both MC3T3-E1 cells and differentiated osteoblasts under $H_2O_2$-induced oxidative stress conditions. In addition, two differentiation markers, alkaline phosphatase activity and mineralization level in the T. mongolicum extract, tended to increase. These results indicate that T. mongolicum extract suppressed the damage to osteoblasts under oxidative stress and that it is potential antioxidant materials for preventing bone diseases.