• Journal of the East Asian Society of Dietary Life
• /
• v.19 no.4
• /
• pp.570-578
• /
• 2009

The present study was conducted to investigate the antioxidant and antimicrobial activities of green tea at different harvest time. The leaves were collected in late March(Ilro), early April(Okro and Ujeon), late April(Sejak), and early May(Eoksu and Hanra). The total polyphenol content of Sejak was highest (28.87mg TAE/g). Electron donating abilities toward $\alpha$,$\alpha$-diphenyl-$\beta$-picyryl hydrazyl (DPPH) radical were approximately 80%. SOD-like activities were above 30%, where ujeon showed the highest activity ($38.95{\pm}0.96%$). The nitrite scavenging ability was pH-dependent and shown to be highest at pH 1.2, and lowest at pH 6.0. The inhibitory effects against the angiotensin I converting enzyme were over 85%, except for Okro ($58.22{\pm}4.66%$) and Hanra ($77.96{\pm}3.83%$). The tyrosinase inhibition rate increased with harvest time. Okro showed the highest caffeine content ($3.86{\pm}0.32%$) and had the highest antimicrobial activities against Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Salmonella typhimurium. The combined results of this work revealed that the antioxidant and antimicrobial activities of green tea were independent of harvest time.

• FLOWER RESEARCH JOURNAL
• /
• v.26 no.4
• /
• pp.202-208
• /
• 2018

This experiment was conducted to determine optimal hot-air drying time for producing antioxidative calendula tea. The edible calendula was dried in hot air at $60^{\circ}C$ for 5, 10, 15 hours and Hunter's color value was measured and extracted with 95% ethanol as a solvent. The contents of total polyphenol, total flavonoid, total carotenoid and DPPH (2,2 Dipheny-1-picrylhydrazyl) radical scavenging activity were investigated. The correlation between the amount of antioxidant and antioxidant activity was analyzed. As the treatment time increased, the Hunter values of L, a, and b tended to decrease, and the L value and b value decreased significantly at 15 hours. The color change was occurred in all treatments compared with the control, and the total color difference (${\Delta}E$) was the largest at 15 hours treatment. The contents of total flavonoids, total carotenoids and DPPH scavenging activity increased in the 5 hours, but decreased in the 15 hours compared to the 10 hours. The content of total polyphenol was not changed with different treatment time. A positive correlation ($p{\leq}0.01$, r = 0.610) between carotenoids and DPPH radical scavenging activity was demonstrated. The DPPH radical scavenging activity was increased at 5 and 10 hours compared to the control and decreased at 15 hours. Therefore, 5 hours or 10 hours of treatment is appropriate and further studies are needed to determine the specific treatment time.

• Journal of Digital Convergence
• /
• v.13 no.7
• /
• pp.431-436
• /
• 2015

To determine fusion-complex activity of Camellia extract extracted hot water, this study was conducted. Special catechin was identified at this extract by analysis of catechin. In analysis of antioxidant activity, the extract was contained antioxidant material and flower among the other parts showed high antioxidant activity. flavonoid showed most high content of Camellia. Flavonoid content was found to be $223.29{\pm}0.005mg/g$ to measured most high to stem, a control group was measured Green tea new leaves $126.14{\pm}0.005mg/g$. Total polyphenol content exhibited most high content at new leaves and flavonoid showed most high content at stem. ${\gamma}$-Amino butyric acid (GAVA) among the free amino acid showed highly at all parts.

• Molecules and Cells
• /
• v.39 no.6
• /
• pp.508-513
• /
• 2016

To investigate the potential therapeutic effects of polyphenols in treating Pb induced renal dysfunction and intoxication and to explore the detailed underlying mechanisms. Wistar rats were divided into four groups: control groups (CT), Pb exposure groups (Pb), Pb plus Polyphenols groups (Pb+PP) and Polyphenols groups (PP). Animals were kept for 60 days and sacrificed for tests of urea, serum blood urea nitrogen (BUN) and creatinine. Histological evaluations were then performed. In vitro studies were performed using primary kidney mesangial cells to reveal detailed mechanisms. Cell counting kit-8 (CCK-8) was used to evaluate cell viability. Pb induced cell apoptosis was measured by flow cytometry. Reactive oxygen species (ROS) generation and scavenging were tested by DCFH-DA. Expression level of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-1-${\beta}$ (IL-1-${\beta}$) and IL-6 were assayed by ELISA. Western blot and qPCR were used to measure the expression of ERK1/2, JNK1/2 and p38. Polyphenols have obvious protective effects on Pb induced renal dysfunction and intoxication both in vivo and in vitro. Polyphenols reduced Pb concentration and accumulation in kidney. Polyphenols also protected kidney mesangial cells from Pb induced apoptosis. Polyphenols scavenged Pb induced ROS generation and suppressed ROS-mediated ERK/JNK/p38 pathway. Downstream pro-inflammatory cytokines were inhibited in consistency. Polyphenol is protective in Pb induced renal intoxication and inflammatory responses. The underlying mechanisms lie on the antioxidant activity and ROS scavenging activity of polyphenols.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.11
• /
• pp.1546-1553
• /
• 2012

In this study, sorghum teas were prepared from Sorghum bicolor L. Moench subjected to different types of milling (no milling (0%), minimum milling (5%), and milling (20%)) and pan-firing times (1 to 10 minutes), and its quality characteristics were investigated. With regards to milling type, total polyphenolic, flavonoid, tannin contents, and antioxidant activities of ethanol extracts from both no milling sorghum and its tea were highest, followed by minimum milling and milling in decreasing order. Crude nitrogen content was highest in milling sorghum and its tea regardless of pan-firing time. With regards to pan-firing time, total polyphenolic, flavonoid, tannin contents, and antioxidant activities of sorghum teas increased with increasing pan-firing time regardless of milling type. The highest DPPH and ABTS radical scavenging activities were observed at a pan-firing time between 7 to 9 minutes. In contrast to ethanol extracts of pan-fried sorghum tea, antioxidant activities, chromaticity, and turbidity of hot water leaching liqueur of sorghum tea were highest in milling sorghum tea, followed by minimum milling and no milling sorghum tea.

• Food Science and Preservation
• /
• v.15 no.4
• /
• pp.582-586
• /
• 2008

Total phenolic compounds and antioxidative activities of rooibos tea(Aspalathus linearis) fractions were studied. Three extracts, using hexane, ethyl acetate, and ethanol, were prepared. Total phenolic compounds were 3069.3 mg/100 g extract in the hexane fraction, 18604.4 mg/100 g extract in the ethyl acetate fraction, and 13458.8 mg/100 g extract in the ethanol fraction. Levels of vanillic acid, caffeic acid, syringic acid, 4-coumaric acid, and ferulic acid were analyzed by RP-HPLC, and totals of 3452.6 and 3156.1 mg/100 g of extract were found in the ethanol and ethyl acetate fraction, respectively. In the DPPH assay, the ethanol fraction(82.2% of contol) and the ethyl acetate fraction(78.9%) showed the highest free radical scavenging capacities. The induction period of each tea fraction in the fish oil rancimat assay was measured. When 500 ppm of the ethanol fraction was applied, a 1.19 h induction period was observed. This was 2-fold greater than the induction period of the control.

• Korean journal of food and cookery science
• /
• v.18 no.4
• /
• pp.433-439
• /
• 2002

In order to increase the antioxidant effect and preference of jujube-omija herbal sauce, we added ethanol extracts of 12 kinds of food and 12 kinds of medicinal herb to the sauce, and then evaluated the antioxidant activity and sensory characteristics. The antioxidant activity of the jujube-omija herbal sauces was greatly increased by the addition of ethanol extracts of foods such as green tea, mugwort, mint, lemon, leek, etc. and those of medicinal herbs such as ginseng. pine needle, the root of arrowroot, orange peel, etc.. Due to the high content of phenolic compounds, the ethanol extracts foods and medicinal herbs appeared to be responsible for high electron-donating ability and low hydroperoxide productivity. While the jujube-omija sauce with the extracts of green tea, mugwort, ginseng and pine needle were not preferred by the panels due to bitter taste and aroma, those of lemon, fruit of Chinese quince, orange peel, etc. were preferred with their sweet and a little sour taste and showed a high antioxidant activity. Especially, lemon juice was the best to increase the antioxidant activity and the preference of the jujube-omija herbal sauce.

• Korean Journal of Medicinal Crop Science
• /
• v.20 no.5
• /
• pp.331-338
• /
• 2012

In the present work, mulberry fruit extracts by four extraction processes, namely wet pressing extraction (WPE), hot-water extraction (HWE), enzymatic hydrolysis (EH), and lactic-acid bacteria fermentation (LBF) by Lactobacillus plantarum TO-2100, were analyzed for nutrients and functional compounds. The sugar contents of extracts by WPE, HWE, EH, and LBF were 12.0, 10.9, 14.5, and 14.3 brix, respectively, and the extraction yields by EH and LBF were 1.65 and 1.50 times higher than those by WPE. Among the organic acids, tartaric acid and malic acid contents were the highest in the extracts by WPE. Acetic acid was best extracted by LBF, and citric acid was best extracted by EH. Lactic acid was detected only in LBF. The extracts by EH showed the highest contents of all vitamins with an exception that the extracts by LBF showed the highest contents of the folic acid, vitamin B12, and vitamin C. We also noted that vitamin B group was not detected in the extracts by LBF. The extracts by EH showed the highest contents of all the amino acids, whereas LBF showed the lowest. Polyphenol contents of extracts by EH and LBF were 3.05 and 2.51 times more than those by WPE respectively. Anthocyanin contents were 7.66, 7.14 times higher for EH and LBF compare to WPE. We manufactured mulberry fruit granular teas with different compositions and tested them for their sensory characteristics. We found that 15% mulberry fruit extracts by enzymatic hydrolysis and 85% dextrin composition gave the most satisfactory result.

• The Korean Journal of Food And Nutrition
• /
• v.29 no.4
• /
• pp.557-564
• /
• 2016

This study was performed to develop and evaluate beverage prepared with optimally roasted seoritae to maximize the isoflavone content and antioxidant activities of the beverage. Isoflavone content was maximized at the roasting temperature of $110^{\circ}C$ for 20 min. Both DPPH radical scavenging activity and ABTS radical scavenging activity along with total polyphenol content were highest when seoritae was roasted at $110^{\circ}C$ for 20 min. Western blotting was used to determine the level of nuclear factor of activated T-cells 1(NFATc1) involved in controlling osteoclast differentiation. The results showed that NFATc1 had a concentration-dependent inhibitory effect when the RoS110 (roasted seoritae at $110^{\circ}C$ for 20 min) samples were processed at varying concentrations (10, 50, and $100{\mu}g/mL$). Tea samples were prepared from optimally roasted seoritae by varying brewing times (5~90 min) at $65^{\circ}C$, and tea brewed for 60 min had the highest preference with $65^{\circ}C$ as the preferred temperature for drinking.

• The Korean Journal of Food And Nutrition
• /
• v.27 no.4
• /
• pp.725-731
• /
• 2014

This study aims to find the correlation the low-molecule fucoidan for cancer prevention with an accelerated formation of cotinine. In the presence of fucoidan, a nicotine to cotinine coversion was studied in established assay, direct mixture method and Hep-G2 cell line method. Fucoidan of $1{\mu}g/mL$ showed the potential effect for converting nicotine to cotinine in the direct mixture method compared to control. Increase of conversion rate at the treatment of fucoidan is exhibited as 15 times compared to control. In Hep-G2 cell treatment, fucoidan showed the potential activity for converting nicotine to cotinine as 6 times compared to control. Therefore, fucoidan was shown to be effective in the conversion of nicotine into cotinine even though it is not higher content of polyphenol and flavonoid than its of green tea extract.