• Journal of the Korean Society of Food Culture
• /
• v.22 no.3
• /
• pp.353-358
• /
• 2007

This study was conducted to compare the antioxidant activities of fermented soy products such as chungkukjang, meju and doenjang with soybeans. Total phenolic, flavonoids contents and antioxidative activities of the methanol extract of soy and fermented products were compared with specific reference to alpha-diphenyl-2-picryl-hydrozyl (DPPH) radicals scavenging effects, ferric /reducing power (FRAP), inhibition of conjugated diene formation and tyrosinase activities. Total phenolic and flavonoids contents increased in soybeans after fermentation. Fermented soy products also displayed enhanced antioxidative activities in comparison with the non-fermented soybeans. There were linear relationships between total phenolic and flavonoids contents and ferric reducing/antioxidant power of the samples. Overall, the fermented soy products showed a better antioxidant activity than soybeans. Among the 3 kinds of fermented soy products, chungkukjang, meju and deonjang, doenjang exhibited the highest levels of DPPH-free radicals scavenging activity, ferric /reducing power, inhibition of conjugated diene formation and tyrosinase activities. The fermented soy products with longer fermentation time demonstrated the higher antioxidant activities as well as higher total phenols and flavonoids in the order of doenjang > meju > chunghlkjang> soybeans.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.3
• /
• pp.521-528
• /
• 2016

The antioxidant activity of 70% methanol, 70% ethanol and chloroform-methanol (CM, 2:1, v/v) extracts from turmeric (Curcuma longa L.) was investigated in this study. The antioxidant potential of various extracts of turmeric was evaluated by using different antioxidant tests, namely DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, ABTS [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt] radical scavenging activity, ferric reducing antioxidant power and ${\beta}$-carotene bleaching assays as well as total phenol content and total flavonoid content. All extracts exhibited abundant total phenol content, total flavonoid content and strong antioxidant activity. Particularly, higher activity was exhibited by CM extract with $46.32{\pm}0.35mgCAE/g$ and $15.58{\pm}0.39 mgQE/g$ of total phenol content and total flavonoid content. Generally, antioxidant activity of various extracts from turmeric increased in the following order: 70% methanol extract, 70% ethanol extract and CM extract, respectively. Results suggested that turmeric could be widely used as a source of antioxidant and a kind of functional material in food.

• Journal of Environmental Science International
• /
• v.25 no.5
• /
• pp.695-703
• /
• 2016

The purpose of this study was to measure the bioactivity and antioxidant activity of Orostachys japonicus A. Berger. Orostachys japonicus A. Berger have been known to contain functional materials such as kaempferol, hydroquinone, methyl gallate, quercetin, gallic acid etc. To identify the main functional materials of Orostachys japonicus A. Berger, the contents of flavonoid and phenol were measured. We extracted Orostachys japonicus A. Berger powder from four solvents such as chloroform:methanol (CM, 2:1, v/v), distilled water (DW), 70% methanol, 70% ethanol. After that, this study determined tannin, total phenol, flavonoid content, DPPH radical scavenging activity, ABTS radical scavenging activity, ferric reducing antioxidant power and reducing power of Orostachys japonicus A. Berger extracts and as results of comparing each extract. respectively. From the above results shows that antioxidant activity and bioactivity of Orostachys japonicus A. Berger extracts was higher in the order of 70% ethanol, 70% methanol, DW and CM (p<0.05). The results showed that antioxidant activity of Orostachys japonicus A. Berger extracts supposed to affect by the total phenol and flavonoid contents.

• The Korean Journal of Food And Nutrition
• /
• v.35 no.2
• /
• pp.96-105
• /
• 2022

This study compared and analyzed the antioxidant effect of Doenjang prepared from vegetable water, and explored the optimal addition ratio of vegetables of 5 kinds and the possibility of application to Doenjang. The sample is three kinds of vegetable water (VW1, VW2, VW3) prepared by adding different ratios of radish, carrot, green onion, onion and shiitake mushroom and Denjang prepared using it. Doenjang was aged and fermented at about 40℃ for 40 days, and then separated and used only solids. The content of their antioxidant compounds was measured the content of total phenolic acid contents and total flavonoid contents. In addition, the antioxidant effect was measured by electron donating activity, SOD-like activity, ABTs radical scavenging activity and reducing power. The total phenolic acid contents and total flavonoid contents were high at VW3 and that Doenjang made with VW3. Electron donating activity and SOD-liked activity were high at VW2 and Doenjang made with VW2. ABTs radical scavenging activity was high in Doenjang made of VW3, and Reducing power was high in VW3. Therefore, if Doenjang is prepared with vegetable water prepared by properly mixing 5 types of vegetables, the possibility of developing Doenjang with high antioxidant effect was suggested.

• Journal of the Korean Applied Science and Technology
• /
• v.33 no.4
• /
• pp.741-750
• /
• 2016

The acai berry (Euterpe oleracea Mart.) contains vitamin B complex, vitamin C, anthocyanin and so on. Especially acai berry was seen as nutritionally comparable to blueberry and related berries. The acai berry has significant aging-reducing properties. Compounds have been found to have anti-aging and antioxidant components. Acai berry was extracted with 70% methanol, 70% ethanol and CM (chloroform:methanol=2:1, v/v). After sample and reagents of each experiment was reacted, DPPH radical scavenging activity and ABTS radical scavenging activity, ferric reducing antioxidant power, reducing power were measured to determine the antioxidant capacity, and as results of comparing each extract. Ethanol (70%) extraction was measured highest. Anthocyanin, total phenol, flavonoid also appeared similar to the results. In addition, the antioxidant activities of the extraction solvents were increased significantly with increasing concentrations, but showed lower antioxidant activity than the positive control (ascorbic acid). As a result, antioxidant activities of sample supposed to affect by the anthocyanin, phenol and flavonoid contents.

• Food Science and Biotechnology
• /
• v.18 no.6
• /
• pp.1435-1438
• /
• 2009

Hydrothermal treatment of rice hull was hydrothermal carried out at 105, 110, $121^{\circ}C$ for 15, 30, 60 min, respectively, using a conventional autoclave. Antioxidant activity of the hydrothermal treated rice hull extract was evaluated by determining total phenol contents (TPC), 1,1-diphenyl-2-picylhydrazyl (DPPH) radical scavenging activity (RSA), reducing power, and ABTS RSA. TPC, DPPH RSA, reducing power, and 2,2-azinobis(3-ethylenebenzothiozoline-6-sulfonic acid) (ABTS) RSA of the extract were significantly increased with increasing treated temperature and time. For example, hydrothermal extracts at $121^{\circ}C$ for 60 min increased the TPC, DPPH RSA, reducing power, and ABTS RSA to 0.840 mg/mL, 64.77%, 1.437, and 92.11%, respectively, while those of the extracts treated at $105^{\circ}C$ for 60 min were 0.508 mg/mL, 51.23%, 0.819, and 45.22%, respectively. The results indicated that hydrothermal treatment of rice hull was very effective to increase phenolic compounds and antioxidant activity of rice hull extract.

• Korean Journal of Medicinal Crop Science
• /
• v.15 no.5
• /
• pp.335-338
• /
• 2007

Five samples (Bakwoonbae, Chungsilbae, Sandolbae, Dolbae, and Chuwhangbae) of Pyrus species differing in their origin of production were analyzed for total phenolic content, vitamin C content, and antioxidant activities. Two antioxidant activities were measured by the free-radical scavenging activity and reducing power method. Total phenolic content of the Chungsilbae extract (20.35 mg/g) was higher than those of other pears. Vitamin C content in five Pyrus species ranged from $420.32\;{\mu}g/g$ in Sandolbae to $659.75\;{\mu}g/g$ in Bakwoonbae. Chungsilbae also had the highest free radical scavenging activity (76.56%) and reducing power (0.35).

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.10
• /
• pp.1591-1602
• /
• 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.

• Korean Journal of Community Nutrition
• /
• v.13 no.1
• /
• pp.91-99
• /
• 2008

The present study was conducted to examine metabolic risk factors and total antioxidant capacity (TAC) of Korean females living in Seoul and to investigate the relationship between the metabolic risk factors and serum TAC. A total of 353 females aged between 20 and 64 participated in the study. Obesity indicators, blood pressure, serum lipid profile and fasting blood glucose were measured as metabolic risk factors. Ferric reducing antioxidant power (FRAP) assay was employed to determine serum TAC of subjects. Obesity indicators such as body mass index, waist circumference and waist-hip ratio were significantly higher in the participants aged $\geq$ 50 y (older group) than in the participants aged 20-49 y (younger group) (p < 0.001). Blood pressure, serum total cholesterol (TC), triglyceride (TG) and fasting blood glucose were also significantly higher in the older group than in the younger group (p < 0.001), demonstrating significant positive correlations between age and MS risk factors. The association between FRAP and MS risk factors were also investigated. FRAP values showed significant positive correlations with age (p = 0.001), serum TG (p = 0.002) and TC (p = 0.03). A tendency of positive association between FRAP and waist circumference was observed without any significant difference (p = 0.06). Increased serum FRAP with central obesity and serum lipids may be interpreted as results of activation of antioxidant defense system against oxidative stress induced by metabolic syndrome (MS) constituent factors. However, to verify the function of FRAP as a potential biomarker of susceptibility to MS various contributors to the plasma antioxidant capacity and their biological relevance related to MS should be elucidated further.

• Journal of Applied Biological Chemistry
• /
• v.53 no.1
• /
• pp.8-12
• /
• 2010

The antioxidant activity of hawthorn fruit (Crataegus pinnatifida Bunge var. typica Schneider) extracts was investigated by several in vitro antioxidants properties, including DPPH free radical scavenging activity, total phenolic and flavonoid contents, hydroxyl radical scavenging activity, reducing power activity, iron-chelating capacity and nitrite scavenging activity. Among the extracts in this study, the 70% EtOH extract showed higher antioxidant activity than the others. The $IC_{50}$ value of DPPH free radical scavenging activity was $99.26\;{\mu}g/mL$. Furthermore, the 70% EtOH extract also showed significantly high total phenolic and flavonoids contents and reducing power activity. However, the MeOH extract exhibited stronger effects on hydroxyl radical scavenging activity, iron-chelating capacity and nitrite scavenging activity. All the results implicated that, the hawthorn fruit may has the available potential to be utilize as a potential source of natural antioxidant.