• Applied Biological Chemistry
• /
• v.27 no.4
• /
• pp.264-270
• /
• 1984

In order to obtain mutagenic data of enzymatic browning reaction products, we investigated their mutagenicity. The rec-assay with Bacillus subtilis strains $H17(rec^+)$ and $M45(rec^-)$ were carried out with their spores. Detection of double strand breakage in calf-thymus DNA was investigated into sample solution with and without $Cu^{2+}$ by the agarose slab gel electrophoresis. In the rec-assay, catechol, pyrocatechol, DL-dopa, 3,4-dihydroxytoluene, hydroquinone, hydroxyhydroquinone with and without $Cu^{2+}$ in 0.05M ana 0.1M at the enzymatic browning reaction products stowed mutagenic action. And also browning solution of 0.05M hydroxyhydroquinone and catechol with $Cu^{2+}$, hydroquinone with and without $Cu^{2+}$ of 0.1M at the enzymatic browning reaction products were strong mutagenic action. The DNA breakability of the enzymatic browning reaction products of 0.1M pyrogallol was stronger than that of 0.05M pyrogallol browning solution with $Cu^{2+}$ and 3,4-dihydroxytoluene browning solution was stronger than that of 0.01M 3,4-dihydroxytoluene browning solution.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.9
• /
• pp.1235-1241
• /
• 2012

Antioxidant properties and antioxidant compound contents in different parts of 14 commercial mushrooms were evaluated. Methanolic extracts from the entire mushroom, the pileus and the stipe, separately, were screened for their DPPH and ABTS free radical scavenging activities. Total ubiquinones (Coenzyme Qs; CoQs), total phenolic, and flavonoid contents were determined, in order to assess the extract's antioxidant activity. The portion of the mushroom selected had an effect on the results, with pileus methanolic extract exhibiting the greatest antioxidant effect (p<0.05). The analyzed mushrooms contained powerful antioxidants such as phenols (144.5~536.6 mg of gallic acid equivalents, mg GAE/100 g of dried weight, dw), flavonoids (3.7~31.2 mg of quercetin equivalents, mg QE/100 g dw) and ubiquinones (65.6~485.1 ${\mu}g$/100 g dw). Content of CoQ9 and CoQ10 in the 14 commercial mushrooms varied from 23.1 to 256.2 ${\mu}g$/100 g and from 16.1 to 238.3 ${\mu}g$/100 g, respectively. Phellinus linteus showed the highest antioxidant activity among all species due to the contribution of antioxidants such as phenols (530.5 mg GAE/100 g dw) and ubiquinones (308.8 ug/100 g dw). A positive linear correlation was demonstrated between free radical scavenging activity and total phenolic ($R^2=0.79$) and ubiquinone ($R^2=0.59$) contents in the pileus of mushrooms (p<0.05). Our data indicate that commercial mushrooms have potential as dietary sources of CoQs and phenolic antioxidants.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.1
• /
• pp.143-148
• /
• 2016

This study investigated the lignan content, total phenol content, and antioxidant activities [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and oxygen radical absorbance capacity (ORAC)] of fermented sesame by cultivars. The results showed that the lignan contents of fermented and non-fermented sesame ranged from 2.35~6.58 mg/g and 2.17 to 6.58 mg/g, respectively. The highest total phenol contents of fermented and non-fermented sesame were 51.90 mg gallic acid equivalent (GAE)/g and 25.94 mg GAE/g, respectively. DPPH radical scavenging and ORAC value ranged from 37.95 to 82.57% and from 172.34 to $1,067.80{\mu}M$ TE/g in non-fermented sesame and fermented sesame, respectively. Fermented sesame had higher lignan content, total phenol content and antioxidant activities. than those of non-fermented sesame. Fermented sesame subjected to bioconversion showed increased lignan content and high antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.3
• /
• pp.356-362
• /
• 2015

Prickly pear cactus cladodes were extracted with hot water and 70% ethanol, followed by fractionation with n-hexane (HF), ethyl acetate (EF), n-butanol (BF), and distilled water. Total phenolics and total flavonoid contents as well as antioxidative and anti-inflammatory activities were then measured. Total phenolic contents were 784, 452, and 220 mg gallic acid equivalents (GAE)/g, whereas total flavonoid contents were 214, 76, and 113 mg quercetin equivalents (QE)/g in EF, BF, and HF, respectively. DPPH and ABTS radical scavenging activities ($IC_{50}$) were 103 and $105{\mu}g/mL$ in EF, 359 and $379{\mu}g/mL$ in BF, and 469 and $605{\mu}g/mL$ in HF, respectively. Oxygen radical absorbance capacity was highest at $391{\mu}M$ TE in EF (in decreasing order of $117{\mu}M$ TE in BF and $64{\mu}M$ TE in HF), whereas superoxide anion radical scavenging activity ($IC_{50}$) was highest at $40{\mu}g/mL$ in EF (in decreasing order of $69{\mu}g/mL$ in BF and $98{\mu}g/mL$ in 70% ethanol extract). Inhibitory activity ($IC_{50}$) of nitric oxide (NO) production induced by LPS-activated RAW264.7 cells was highest at $62{\mu}g/mL$ in HF (in decreasing order of $104{\mu}g/mL$ in EF and $465{\mu}g/mL$ in BF). The selectivity index (ratio of inhibitory activity of NO production to cell cytotoxicity) was highest at 4.63 in EF (in decreasing order of 3.37 in HF and 2.14 in BF). In conclusion, EF showed potent antioxidant and anti-inflammatory effects with high phenolic and flavonoid contents.

• Korean Journal of Food Science and Technology
• /
• v.47 no.4
• /
• pp.534-538
• /
• 2015

The purpose of this study was to investigate the biological benefits of apple peel. The antioxidant and anti-inflammatory activities of a 70% ethanol extract of apple peel were examined. The total phenolic compound and flavonoid contents of apple peel were $6.8{\pm}0.5mg$ gallic acid equivalent/g of fresh weight and $3.3{\pm}0.3mg$ catechin equivalent/g of fresh weight, respectively. Antioxidant activity was evaluated by measuring 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The DPPH radical scavenging activity of apple peel was $18.9{\pm}1.6$, $46.3{\pm}2.3$ and $58.1{\pm}3.9%$ at concentrations of 0.1, 0.5 and 1.0 mg/mL, respectively (p<0.05). The anti-inflammatory effect was investigated by measuring the inhibition of inflammatory enzymes. Apple peel significantly inhibited secretory phospholipase, cyclooxygenase-1, cyclooxygenase-2, and lipoxygenase activity by up to $53.5{\pm}2.3$, $13.4{\pm}1.8$, $64.8{\pm}5.4$ and $44.4{\pm}4.5%$, respectively (p<0.05). Taken together, these findings suggest that apple peel may act as an antioxidant by radical scavenging and may possess potential anti-inflammatory properties for suppressing the activity of inflammatory enzymes. These results also suggest that apple peel can be utilized as a health functional food ingredient possessing antioxidant and anti-inflammatory activities.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.8
• /
• pp.1055-1061
• /
• 2007

Caesalpinia sappan L. is an indeciduous tree distributed in China, India, Miyanmar and Vietnam. Its heartwood has long been used in oriental folk medicines to treat diseases. In this study, antioxidative activities of Caesalpinia sappan L. and the effect of gamma irradiation on its chemical and biological properties were investigated. The ethyl acetate fraction (EtOAc fr.) of Caesalpinia sappan L. was irradiated with 100 kGy of gamma ray. The dark red color of EtOAc fr. was significantly (p<0.05) removed by irradiation (Hunter L and b values increased and a value decreased). The total phenolic content of EtOAc fr. was 865 mg/g and it was increased to 1195 mg/g by gamma irradiation. DPPH radical and superoxide anion radical scavenging activities and lipid peroxidation inhibitory activity of EtOAc fr. were very high and its activities were also increased by gamma irradiation. EtOAc fr. also inhibited the irradiation-induced DNA damage of lymphocyte as determined by comet assay. In conclusion, EtOAc fr. of Caesalpinia sappan L. extract showed high antioxidative activities in vitro. Furthermore, gamma irradiation on EtOAc fr. ameliorated the color and antioxidative properties. Therefore, it can be suggested that Caesalpinia sappan L. may be a good material for antioxidant function and gamma irradiation may be applied for the improvement of chemical and biological properties of Caesalpinia sappan L.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.5
• /
• pp.545-551
• /
• 2017

Curcuma longa L. (CL) is widely used as a spice and coloring agent in several foods, such as curry and mustard, as well as cosmetics and drugs. In this study, we investigated the protective effects of CL extracted with various solvents [methanol (MC), ethanol (EC), acetone (AC)] on $H_2O_2-induced$ DNA damage in human leukocytes along with total polyphenol contents (TPC) and antioxidant properties. The antioxidant effects of CL were determined by measuring 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (RSA) and superoxide dismutase (SOD)-like activity. The preventive effect of CL on oxidative stress-induced DNA damage and DNA repair capacities were assessed using comet assay. MC showed the highest TPC (11.17 g gallic acid equivalents/100 g) and antioxidant properties among the solvent extracts. The $SC_{50}$ for DPPH RSA was MC: 35.0 > AC: 45.8 > EC: $57.8{\mu}g/mL$ and SOD-like activity was MC: 46.6 > EC: 141.5 > AC: $296.4{\mu}g/mL$. In the comet assay, the $ED_{50}$ value of MC showed the highest inhibition ($86.7{\mu}g/mL$) of $H_2O_2-induced$ DNA damage, followed by AC ($110.0{\mu}g/mL$) > EC ($115.8{\mu}g/mL$). Analysis of the percentage of damaged cells showed that repair capacity significantly decreased at 4, 8, and 12 h from $H_2O_2-induced$ oxidative stress in each extract. After 12 h, level of DNA damage recovery was similar to the negative control level. These results suggest that CL has potential antioxidant activity and a protective effect against oxidation-induced DNA damage, and the methanol extract of CL was the most effective.

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

• Korean Journal of Food Science and Technology
• /
• v.41 no.1
• /
• pp.82-86
• /
• 2009

The objective of this study was to evaluate the effect of various solvents on extraction of bioactive phenolics and to analyze the antioxidant capacity and contents of individual catechins in various grades of green teas organically grown in Boseong, Korea. The organic green teas, based on their harvest seasons, were categorized into five grades such as Woo-Jeon, Se-Jak, Jung-Jak, Dae-Jak, and coarse tea. Solvents used to extract phenolics from these teas included water at $23^{\circ}C$ and $70^{\circ}C$ as well as 80% (v/v) aqueous methanol and ethanol. In general, aqueous organic solvents of methanol and ethanol led to higher extraction yields of phenolics than water at $23^{\circ}C$ and $70^{\circ}C$. Total phenolics and antioxidant capacity of the teas extracted with the aqueous organic solvents were approximately 1.5 to 3.2 and 1.8 to 3.8 times higher than those with water at $23^{\circ}C$ and $70^{\circ}C$, respectively. Coarse tea, the lowest grade of green tea, showed approximately 30-60% lower total phenolics and antioxidant capacity compared with the higher grade ones. Reversed-phase HPLC analysis was performed quantitatively to identify individual catechins, gallic acid, and caffeine in teas extracted with 80% (v/v) aqueous methanol. Based on their dry weights, the organic green teas contained about 1.7 to 2.9% of caffeine. Content (mg/g dry weight) of tea catechins decreased in the following order: Woo-Jeon (155.4) > Se-Jak (147.7) > Jung-Jak (143.2) > coarse tea (135.1) > Dae-Jak (130.5). (-)-Epigallocatechin gallate was the most abundant among the catechins analyzed. The highest grade of green tea, Woo-Jeon, had the highest amount of (-)-epigallocatechin gallate at 77.4 mg/g dry weight. Overall, the higher grade of organic green teas tended to have the higher level of antioxidant capacity and catechins.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.9
• /
• pp.1133-1138
• /
• 2006

Smilax china root has been used as traditional medicinal remedy in China and Korea and reported to have various biological activities such as anti-inflammatory, antimutagenic and antimicrobial activities. In this study, the possibility of development as natural antioxidants of Smilax china root extracts was investigated. For the evaluation of antioxidant activity, aqueous- and 25% EtOH extract from Smilax china root were prepared and six different evaluation assay methods, i.e., measurement of total phenolics, radical scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO) and nitrite $(NO_2)$, reducing power, and inhibitory effect on tyrosinase activity, were used. The total phenolics content of two extracts was high as the level of 36 mg of gallic acid equivalent per 1 g of dried sample tested. The radical scavenging activities of ethanol extract toward DPPH and NO were better than those of aqueous extract (p<0.05). The $NO_2$ scavenging activity of both extracts showed the highest value at pH 1.2 (98%). Especially, the $NO_2$ scavenging activities of EtOH extract were significantly stronger than those of aqueous one at pH 4.2 (51%) and pH 6.0 (32%), respectively. In the reducing power test, both extracts revealed higher ferric ion reducing activity than known antioxidant, vitamin C at the level of $0.05\sim0.1mg/mL$ (p<0.01). The 1 mL of aqueous and 25% EtOH extract showed effective inhibition activity on tyrosinase activity as 45% and 53%, respectively. Therefore, these results suggest that two extracts from Smilax china root may serve as useful natural antioxidants.