• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1613-1618
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• 1999

Extracts of Citrus sudachi juice and peel were obtained by several organic solvents such as hexane, acetone, ethyl acetate and methanol. Their antimicrobial spectrum were determined against 14 strains of gram positive and 4 strains of gram negative bacteria by paper disk method and minimal inhibitory concentration (MIC) was also obtained. Antimicrobial activities of solvent extracts from Citrus sudachi juice showed stronger than those of solvent extracts from peel. Acetone extract from juice showed the strongest antimicrobial activity among extracts, but the hexane extract did not show antimicrobial activities on tested target strains. The MIC was differant among tested strains; i.e. 0.5% (v/v) to Bacillus subtilis, 1% to Pseudomonas fragi, 1.5% to Listeria monocytogenes and Escherichia coli O157:H7, 2% to Propionibacterium acnes and Salmonella typhimurium, and 2.5% to Staphylococcus aureus.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.51-56
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• 2002

This study was carried out to develop a traditional functional beverage by using hot-water extraction of dried peels of Korean tangerine. The pH of the hot-water extracts of dried tangerine peels decreased as the extraction time increased. The acidity and viscosity of the extracts increased as the extraction time increased. The antioxidative activity of the extracts during the extraction was monitored by measuring the electron donating ability. The electron donating abilities of the extracts were in the range of 80.93-83.27%. Extraction time did not affect the antioxidative activity of the extracts. The fibrinolytic activity of the extracts increased as the extraction time increased. The pH of the beverage made with the peel extract was not affected by the extraction time and the kind of sweetener added. The viscosity of the beverage increased as the extraction time increased. In sensory evaluation the highest score was obtained in the beverage samples made with the ones extracted for 180 min and added with sugar. The aboveresults indicate that the dried peel of Korean tangerine can be used as a functional material in beverage industry.

• Journal of Nutrition and Health
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• v.37 no.8
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• pp.633-644
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• 2004

This study was performed to investigate effect of dried powders and ethanol extracts of garlic flesh and peel on antioxidative capacity in 16-month- old rats. Forty Sprague-Dawley male rats weighing 618.1$\pm$6.5g were blocked into five groups according to body weight and raised for 3 months with experimental diets containing 5% (w/w) of dried powders of garlic flesh or peel, or ethanol extracts from equal amount of each dried powder. Total polyphenols, flavonoids, /3 -carotene, vitamin C, vitamin E, and total antioxidant status (TAS) levels were determined in garlic preparations. Thiobarbituric acid reactive substances (TBARS) levels in plasma, liver and VLDL + LDL fraction, oxidative DNA damage (8-hydroxy-2' -deoxyguanosine, 80HdG) in kidney, xanthine oxidase (XO) activities in plasma and liver, superoxide dismutase (SOD) activities in erythrocyte and liver, and carotenoid concentration, and total antioxidant status (TAS) in plasma were measured. Total polyphenols and flavonoids contents in garlic preparations were highest in peel ethanol extract. Vitamin C content was not different significantly among preparations, but peel powder contains slightly more vitamin C. The content of $\beta$-carotene was highest in peel ethanol extract and vitmain E content was highest in flesh ethanol extract. The highest level of TAS was observed in peel ethanol extract. Plasma TBARS levels in all the experimental groups were found to be significantly lower than control group, and TBARS concentration in VLDL + LDL fraction was decreased in all the experimental groups in comparison to control group. Also levels of 80HdG in kidney in experimental groups were lower than that of control group. Plasma and liver XO activities were. decreased in all experimental groups, and erythrocyte and liver SOD activities were higher in experimental groups compared to control group. All experimental groups also showed higher plasma TAS levels than control group. Especially, garlic flesh powder group was significantly lower in plasma and liver XO activities, and significantly higher in erythrocyte and liver SOD activities than control group. Moreover, plasma TBARS level and kidney 8OHdG level were decreased in flesh powder group. In conclusion, garlic diets showed effect of improving antioxidative capacity in 16-month old rats, especially, garlic flesh powder was prominent in inhibiting XO activity, promoting SOD activity and decreasing kidney 8OHdG level among experimental groups.

• Food Science and Preservation
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• v.10 no.3
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• pp.388-393
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• 2003

Citrus peel extract was prepared using 70％ ethanol solution by two extraction conditions (20$^{\circ}C$ for 72 hours and 85$^{\circ}C$ for 3 hours). The effect of gamma-irradiation on the changes of physiological activity also investigated at 0, 5, 10 and 20 kGy of absorbed doses. Color characteristics, DPPH radical scavenging, tyrosinase inhibition and nitrite scavenging activities of the extracts were measured at 41$^{\circ}C$ for 30 days. Color values were different by extraction methods at the initial stage, which heat-extracted sample had lower L$\^$＊/ - but higher a$\^$＊/ - and b$\^$＊/ -values than those extracted at room temperature. Irradiation changed color of the extract lighter by increasing Hunter color L$\^$＊/ - and a$\^$＊/ -values. DPPH radical scavenging, tyrosinase inhibition and nitrite scavenging activities were not affected by either extraction methods or irradiation but significantly reduced by storage time. Therefore, when the cost-effective extraction methods is selected, the citrus peel extracts, which is a major byproduct in citrus processing, could be used as a functional material in various applications.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.31-36
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• 1997

This study was conducted to investigate the physiological functionality of the hot water, 70% acetone and 70% methanol extracts from the pumpkin. Extraction yield and pH of each solvent extract from various parts of pumpkin were investigated. Extraction yield from flesh were from 63.7% for 70% acetone to 68.2% for hot water. pH of 70% acetone extracts and hot water extracts were 5.01∼5.45 and 5.78∼6.22, respectively, and pH of the flesh part was the highest. The content of soluble solid was the highest in methanol extracts. Flesh part contained the highest concentration of soluble solid. Color of the extracts from fiber was higher than that of other parts. The content of the total sugar was in the decreasing order of flesh, fiber and peel. The content of total polyphenol and flavonoid from each solvent extract of peel was higher than that of other parts. Some differences were observed in physiological functionality of each solvent extracts from various parts of pumpkin. The nitrite scavenging ability of hot water extract from flesh, acetone and methanol extract from fiber and edible portion was higher than other parts. The electron donating ability was the highest in acetone and methanol extracts of peel, methanol extracts of flesh and edible portion, and acetone extracts of fiber.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.353-358
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• 2014

Antioxidant activities of ethanol and water extracts of flesh, leaves, and peels of green and purple Kohlrabi were measured by rancimat method, total phenolic compound (TPC), DPPH radical scavenging effect, chelating effect, and reducing power analysis. The highest TPC was observed in ethanol extract from green peel and water extract from purple leaf with 12.00 and 11.70 mg/g of dry sample, respectively. The ethanol extracts from purple Kohlrabi leaf and peel exhibited strong DPPH radical scavenging effects with reducing power while water extracts from purple Kohlrabi leaf and peel also showed strong DPPH radical scavenging with chelating effects. Antioxidant index of ethanol and water extracts from green and purple Kohlrabi measured by rancimat was lower than butylated hydroxytoluene. These results suggest that extracts from purple Kohlrabi leaf and peel exhibited higher antioxidant activities than those of green Kohlrabi, and can be potentially used as proper natural antioxidants.

• Journal of Life Science
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• v.19 no.11
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• pp.1598-1604
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• 2009

In order to determine chemical components of onion flesh and peel, general nutrients, vitamin C, and total flavonoids were measured. Onion peel showed less moisture (14.3%) and no vitamin C compared to onion flesh. Onion peel contained more amounts of total flavonoids compared to onion flesh. In addition, the inhibitory effects of solvent extracts from onion flesh and peel on $H_2O_$-induced oxidative stress and growth of cancer cell lines (AGS human gastric adenocarcinoma and HT-29 human colon cancer cells) were investigated. Acetone with methylene chloride (A+M) and methanol (MeOH) extracts from onion flesh and peel appeared to significantly reduce the levels of intracellular reactive oxygen species (ROS) (p<0.05) and a greater antioxidant effect was observed in onion peel. Among fractions, 85% aq. methanol showed a higher protective activity against oxidative stress in both flesh and peel and there was no effect in the water and hexane fractions. The growth of cancer cells exposed to medium containing extracts and fractions from onion flesh and peel was inhibited dose-dependently. The growth of AGS was inhibited more in both flesh and peel compared to HT-29, and onion peel was more effective than onion flesh. Among fractions, 85% aq. methanol showed the greatest effect on growth inhibition in both flesh and peel. $IC_{50}$ values of 85% aq. methanol fraction from onion flesh and peel on AGS were 0.04 and 0.03 mg/ml, respectively, while those on HT-29 were 0.23 and 0.04 mg/ml. From our results, 85% aq. methanol fraction had an inhibitory effect against oxidative stress and growth of cancer cells, suggesting that it may contain biological active compounds.

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.139-145
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• 2000

To separate anticaries and antiinflammation from Aloe vera peel, we investigated a inhibited effect of Streptococcus mutans JC-2 that was antibiosis, glucosyltransferase activity about aloe-emodin and barbaloin. Aloe-emodin and barbaloin had strong antibiosis activity against Streptococcus mutans JC-2, they were especially antibiosis effect to low growth and prolong lag phase at attachment concentration 100$\mu\textrm{g}$/mL. The reduction rate of a culture fluid became to lessen than the comparison group for aloe-emodin and barbaloin. The intracellular materials of Streptococcus mutans JC-2 were to leakage as much as attachment concentration addition of aloe-emodin and barbaloin but there was no significant difference membrane demage between two active substances. The activity of GTase was inhibited by aloe-emodin and barbaloin and their inhibition rate was respectively 99.8%, 98.4% at the attachment concentration 100$\mu\textrm{g}$/mL.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.598-604
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• 2013

This study was designed to evaluate the usability of the following citrus peel extracts (CPEs): Citrus sinensis (orange), C. unshiu (mandarin orange), C. limon (lemon), and C. paradise (grapefruit) as natural antibrowning agents. Overall, 0.1% of the CPEs were effective in reducing the browning of apple slices. The appearance of apple slices dipped in C. limon peel extracts (LPE) were found to be excellent and their Hunter L and ${\Delta}E$ values were similar to the values obtained when apple slices were dipped in ascorbic acid. The pH values of the different CPEs were not significantly different from each other, but were higher than that of ascorbic acid. LPE was found to possess the highest total phenolic content, flavonoid content, DPPH radical scavenging activity, and copper ($Cu^{2+}$) chelating activity. All these results suggest that citrus peel extracts, especially lemon peel extract, can be used as natural antibrowning agents.

• Journal of Life Science
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• v.18 no.1
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• pp.46-51
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• 2008

This study investigated the effects of Punica granatum L. (PG) ethanol extracts on serum lipid levels in ovariectomized rats. In order to elucidate the effects of PG ethanol extracts on the change of lipid concentration in rats, Sprague-Dawley female rats were randomly assigned to groups as follows: sham-operated rats (sham), ovariectomized control rats (OVX-control), ovariectomized rats supplemented with ethanol extracts of PG seed at 50 mg/kg bw/day (OVX-PS50), ovariectomized rats supplemented with ethanol extracts of PG seed at 200 mg/kg bw/day (OVX-PS200), ovariectomized rats supplemented with ethanol extracts of PG peel at 50 mg/kg bw/day (OVX-PS50), ovariectomized rats supplemented with ethanol extracts of PG peel at 200 mg/kg bw/day (OVX-PP200). PG ethanol extracts were orally supplemented at the level of 1mL per day for 7 weeks. The body weight gain, food intake and food efficiency ratio were not significantly different between groups by t-test. The levels of total-cholesterol and triglyceride in serum were not changed by supplementation of PG ethanol extracts. The level of HDL-cholesterol on serum of the OVX-PS50 and OVX-PS200 groups were similar to the OVX-control group, but the OVX-PP50 and OVX-PP200 groups were higher than sham group. These results suggest that ethanol extracts of PG peel were more effected than those of PG seed.