• Journal of Applied Biological Chemistry
• /
• v.51 no.3
• /
• pp.111-116
• /
• 2008

Aralia elata seeds were successively extracted with water, methanol, ethanol, acetone and chloroform. The crude extracts were investigated for antioxidant and antidiabetic activities. The antioxidant properties of various extracts were evaluated by antioxidant tests, such as DPPH free radical-scavenging activity, hydroxyl radical-scavenging assay, metal-chelating activity, lipid peroxidation inhibition activity and reducing power assay. The 70% methanol extract exhibited the highest activity in the in vitro models of DPPH free radical-scavenging activity, metal-chelating activity, and reducing power assay. Acetone extract showed good effects on lipid peroxidation inhibition and hydroxyl radical-scavenging assay at a low concentration. In addition, the $\alpha$-glucosidase inhibition assay showed that 70% methanol extract had the highest activity. These results indicate the high possibility of using A. elata seeds for medical application due to their efficient antioxidant properties.

• The Korean Journal of Pesticide Science
• /
• v.7 no.2
• /
• pp.92-99
• /
• 2003

A 96-well plate was applied to determine the DPPH free radical scavenging activity using 107 plant-specific enzyme inhibitors and 100 unknown plant-originated extracts. The final optimum volume was $250{\mu}L$ containing $100{\mu}M$ DPPH ethanolic solution at pH 7.8. In this condition, the radical scavenging activities were significantly increased by two known antioxidants consisting of ascorbate and a-tocopherol in a concentration-dependent manner. Among the 107 inhibitors, ampicillin and gallic acid showed 90.2% and 92.6% antioxidant activity at $100{\mu}M$, respectively, and these results were consisted with previous findings. In the tested 100 natural materials at $50{\mu}g/mL$, antioxidant activity of AT-407 resulted in the highest of 90.1%, and 10 extracts including AT-388 and AT-443 showed over 70%. Our results suggest that the use of 96-well plate for determining DPPH free radical scavenging activity would be a suitable method to select antioxidant-like substances of both synthetic compounds and natural products.

• Natural Product Sciences
• /
• v.9 no.2
• /
• pp.80-82
• /
• 2003

Since reactive oxygen radicals play an important role in carcinogenesis and other human diseases including neurodegenerative states, antioxidants present in natural products have received considerable attention for alleviation of these disease states. Therefore, in order io identify antioxidants in plant extracts, fifty-seven methanolic extracts derided from indigenous Korean plants were primarily assessed for potential to scavenge stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. As a result, nine plant extracts were found to exhibit the DPPH free radical scavenging activity in the criteria of $IC_{50}<40\;{\mu}g/ml$. In particular, the extracts of Melioma oldhami $(IC_{50}=0.1\;{\mu}g/ml)$, Myrica rubra $(IC_{50}=16.2\;{\mu}g/ml)$, Sympolocos paniculata $(IC_{50}=23.0\;{\mu}g/ml)$, Carpinus laxiflora $(IC_{50}=25.1\;{\mu}g/ml)$, and Cleyera japonica $(IC_{50}=26.2\;{\mu}g/ml)$ showed a potent radical scavenging activity. Further study for the identification of active compounds from these lead extracts might be warranted.

• Preventive Nutrition and Food Science
• /
• v.14 no.1
• /
• pp.86-89
• /
• 2009

In this study, we investigated the free radical [1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (${\cdot}OH$) and superoxide anion (${O_2}^-$)] scavenging activity of MeOH extract and 3 fractions of Citrus junos. Of the tested fractions, the BuOH fraction showed the strongest DPPH scavenging activity, showing the $IC_{50}$ values of 63.4 mg/mL. Therefore, we continuously carried out DPPH, ${\cdot}OH$ and ${O_2}^-$ scavenging activity tests of BuOH fraction of Citrus junos. The BuOH fraction of Citrus junos inhibited DPPH radical to 97.5% at a concentration of 1000 mg/mL and the scavenging activities were increased concentration-dependently. In addition, BuOH fraction from Citrus junos also scavenged ${\cdot}OH$ in a concentration dependent manner from 5 to 1000 mg/mL. Furthermore, BuOH fraction showed about 56% ${O_2}^-$-scavengimg activity at 25 mg/mL concentration but, the scavenging activities were not enhanced in a dose dependent manner. The present results suggest that BuOH fraction of Citrus junos would have the protective potential from oxidative stress induced by free radicals.

• Food Engineering Progress
• /
• v.15 no.3
• /
• pp.221-229
• /
• 2011

Optimization study of the hot water extraction for enhancing antioxidative activity from Auricularia auricula was performed by Taguchi approach using orthogonal matrix $L_9(3^4)$ method. The correlation between DPPH radical scavenging activity and the components of samples extracted from different extraction conditions were also analyzed. The correlation coefficient between DPPH radical scavenging activity and melanin content of A. auricula were 0.93, indicating 'good correlation'. The optimum extraction conditions was obtained at the extraction time of 1 hr. temperature of $85^{\circ}C$, solid: water ratio of 1: 40(w/v) and frequency of 2 times. Under these conditions, values of maximum DPPH free radical scavenging activity and melanin contents of A. auricula were $67.21{\pm}2.17$ and $52.94{\pm}2.10 mg/g$, respectively. Melanin content of 1.6 times and DPPH free radical scavenging effect of 130% were enhanced by optimization.

• Korean Journal of Plant Resources
• /
• v.26 no.5
• /
• pp.548-556
• /
• 2013

The objective of this study was to determine the effect of antioxidant enzyme activity and radical scavenging activities of cucumber grown greenhouse. The analytic method of antioxidant activities were measured by estimating DPPH free radical scavenging, nitrite scavenging ability activity and ABTS radical scavenging ability. The DPPH free radical scavenging activity of Jangjukcheongjang was the highest in most of the growth stage. The Nitrite scavenging ability at pH 1.2 was more than 40% in all cultivars and growth stages. The ABTS radical scavenging ability of Jangjukcheongjang and Nulpureuncheongjang showed relatively little higher than Janghyeongnakhap and Sinjoeunbaekdadagi. The SOD activity showed higher activity than 95% in all cultivars and growth stages. The activity of CAT was highest in the Nulpureuncheongjang of 2 (12~16cm) growth stage, and the APX activity of Nulpureuncheongjang and Janghyeongnakhap showed a relatively high activity. The POX activity showed distinctly different trends depending on the growth stage, and that is, the activity at harvest stage was significantly reduced. These results suggest that the cucumber had the potent biological activities, and that in the future, the availability of cucumber will be increase in the field of high-value cosmetic and food products.

• Journal of the Korean Dietetic Association
• /
• v.25 no.2
• /
• pp.105-114
• /
• 2019

This study examined the quality characteristics of brown rice Sulgidduk containing acorn powder and the optimal mixing rate (0%, 5%, 10%, and 15%). The moisture contents of brown rice Sulgidduk increased with increasing amount of acorn powder. The DPPH free radical scavenging activities (16.15%~28.06%) and ABTS free radical scavenging activities (22.98%~42.81%) of the brown rice Sulgidduk increased with increasing acorn powder content. The L value of the Hunter's color value decreased with increasing amount of acorn powder. The hardness and chewiness of brown rice Sulgidduk increased with increasing amount of acorn powder. The brown rice Sulgidduk containing 10% acorn powder showed the highest score with regard to the sensory characteristics. These results suggest that the most desirable amount of acorn powder is 10% and the addition of acorn powder could contribute positively toward the quality characteristics of brown rice Sulgidduk.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.211.1-211.1
• /
• 2003

On the purpose of develcpement of antioxidative compound from natural sources, medicinal plants known to have antioxidant actuvity have been examined concening DPPH radical scavenging activity and SOD-liked activities. Among 8 plants exhibiting the activity, Houttuynia cordata THUNB was selected as resources to search for active compounds due to rareness of study. The antioxidative compounds from Houttuynia cordata THUNB,quercitrin was assayed using a DPPH free radical. The DPPH radical scavenging activity of quercitrin was similar to that of BHA and Ascorbic acid

• Preventive Nutrition and Food Science
• /
• v.14 no.4
• /
• pp.277-282
• /
• 2009

The antioxidant potency of methanolic extract of Duchesnea indica (MDI; Indian strawberry) was investigated by employing various established in vitro systems, such as total phenolic content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power assay, metal chelating assay, superoxide radical scavenging activity and protective ability of DNA damage and protein oxidation. MDI inhibited metal chelating by 75.57% at 2 mg/mL, scavenged 50% DPPH free radical at 29.13 ${\mu}$g/mL, and eliminated approximately 46.21% superoxide radical at the concentration of 1 mg/mL. In addition, MDI showed strong ability on reducing power, DNA damage protection and protein oxidation protection. Overall, results suggested that MDI might be beneficial as a potent antioxidant and effectively employed as an ingredient in food applications.

• Archives of Pharmacal Research
• /
• v.26 no.7
• /
• pp.535-539
• /
• 2003

The EtOAc soluble fraction from the stem of Sorghum bicolor showed a strong free radical scavenging activity. Five major compounds were isolated from this fraction. They were identified by spectral data as methyl ferulate (1), methyl p-hydroxycinnamate (2), p-hydroxybenzaldehyde (3), tricin (4), and quercetin 3,4 -dimethyl ether (5). Among these compounds, 1 exhibited a strong, free radical scavenging activity on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) with an $IC_50$ value of 0.7 $\mu$M. We further studied the effects of these isolated compounds on the lipid peroxidation in rat liver microsomes induced by non-enzymatic method. All five compounds showed anti-lipid peroxidation activity ($IC_50$ values of 0.5, 0.4, 0.3 and 0.3 $\mu$ M, respectively).