• Korean Journal of Medicinal Crop Science
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• v.25 no.1
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• pp.10-15
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• 2017

Background: We investigated the antioxidative and tyrosinase inhibitory activities of 70% ethanol extract, and its fractions, of the root of Rumex japonicus HOUTT. Methods and Results: The total phenolic compound contents of the 70% ethanol extract and ethyl acetate fraction were 168.99 mg/g and 651.78 mg/g, respectively. The antioxidant activity was compared through the DPPH radical and nitric oxide (NO) scavenging assays. The ethyl acetate fraction showed the highest DPPH radical and NO scavenging abilities, which confirmed the antioxidant activity. Specifically, the ethyl acetate fraction showed a higher DPPH radical scavenging ability than ascorbic acid. These results were related to the total phenolic compound content of the ethyl acetate fraction. Moreover, in the tyrosinase inhibition assay, the ethyl acetate fraction exhibited stronger inhibitory activity than arbutin, which was used as the positive control. The cell viability of L929 cells was analyzed by MTT assay after treatment with 70% ethanol extract and all fractions; no changes in viability were observed, which demonstrated the nontoxic nature of the extract and fractions. Conclusions: These results suggested that the extract from the root of R. japonicus and its ethyl acetate fraction could be a novel resource for the development of a cosmetic with antioxidant and tyrosinase inhibitory activity.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.115-122
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• 2014

In order to select the raspberry cultivars that have high contents of bioactive constituents and high antioxidant activities, 7 cultivated and 2 wild raspberries which were selected and cultivated in the Bokbunja Institute were evaluated for their physicochemical characteristics, bioactive constituents, and antioxidant activities. The wild raspberry of Asan was the smallest among the sample raspberries but it had the highest sugar and lowest acid contents among the raspberries. Another wild raspberry of Ulleungdo had the highest total phenolic compound and ellagic acid contents, 182.97, $55.25mg{\cdot}100g^{-1}FW$, respectively, although it was small and had low sugar and high acid contents. Among the widely cultivated raspberry cultivars in Kimhae, 'Wangttal' cultivar was a big raspberry with 12.80% sugar content, and another unknown raspberry cultivar was as small as the wild raspberry with 14.60% sugar content. Although 'Wangttal' and the unknown raspberry cultivars cultivated in Kimhae possess lower contents of total phenolic compound (159.62, $165.94mg{\cdot}100g^{-1}$) and ellagic acid (45.7, $52.1mg{\cdot}100g^{-1}$ ) than the wild raspberry of Ulleungdo, the contents of total flavonoids (14.28, $14.90mg{\cdot}100g^{-1}$) and total anthocyanins (28.69, $30.48mg{\cdot}100g^{-1}$) were higher. Also the wild raspberry of Ulleungdo, 'Wangttal', and the unknown raspberry cultivar of Kimhae had higher antioxidant activities measured by FRAP (Ferric reducing antioxidant power), DPPH (2,2-diphenyl-1-picrylhydrazyl), and ABTS (2,2' azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) assays. The present study shows that three raspberry cultivars could be potent resources for raspberry breeding and functional material development.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.313-318
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• 2010

This study was carried out to evaluate the antioxidant activity of stevia extracts from Stevia rebaudiana Bertoni leaves. Stevia extracts were prepared by three different methods including hot water extraction (HWE) at $120^{\circ}C$ for 4 hr, vacuum extraction (VE) at $65^{\circ}C$ for 4 hr under 0.08 MPa, and fermentation of hot water extract (FHWE) using Lactobacillus buchneri. The antioxidant activities measured by radical scavenging activity, ferric-reducing antioxidant potential ability, and thiobarbituric acid reactive substance showed the highest values in vacuum extract. Also, the antioxidant activities of all extracts were higher than those of stevioside and rebaudioside at the same concentrations, known as the major active components in stevia. To define the antioxidative compound in stevia extracts, the total phenol content was measured, and it was shown that the highest contents of total phenolic compounds were in vacuum extract. These results suggest that the antioxidant activity of stevia extract was due to the phenolic compound components. In addition, vacuum extraction was the proper method to prepare stevia extract with higher antioxidant activity.

• Journal of Life Science
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• v.28 no.8
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• pp.923-930
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• 2018

In this study, Tenebrio molitor (T. molitor) was fermented with Lactobacillus plantarum JBMI F3 (F3), Lactobacillus plantarum JBMI F5 (F5), Lactobacillus gasseri Ba9 (Ba9), Aspergillus kawachii KCCM 32819 (Ak), Saccharomyces cerevisiae KACC 93023 (Sc), and Bacillus subtilis KACC 91157 (Bs). After fermentation, the fermented products were extracted by water, ethanol, and methanol, and their physicochemical and biological properties were investigated. In a DPPH assay, the water extracts of the fermented products of T. molitor showed high antioxidant ability. Among the water extracts, the fermented product by Bs showed the highest DPPH radical scavenging activity. The total contents of phenolic compounds and flavonoids were highest in the fermented products by Ak and Bs, respectively. Reducing activity was detected the most high activity on ethanol extract of fermented product by Bs. The water extract of the fermented product by Bs exhibited strong enzymatic activity for fibrinogen and starch hydrolysis. Based on the observed physicochemical and biological properties, the fermented products of T. molitor by microorgansims can likely be applied as functional materials in various industries.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.1
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• pp.38-43
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• 2008

Pepper plants (Capsicum annuum, cv. Manitta) were subjected to different intensities of UV-B radiation to understand alterations of primary- and secondary-metabolism such as carbohydrates, phenolic compounds and polyamines. UV-B doses with a UV-B lamp ($1.2W\;m^{-2}$) were adjusted between 0 to 9 hr. The soluble sugars and starch contents in pepper leaves were highly influenced by UV-B treatment. The soluble sugars altered from $6.7mg\;g^{-1}\;fw$ to $5.2mg\;g^{-1}\;fw$ after 9 hrs of UV-B exposure. The starch contents after 3 hrs of UV-B exposure changed from $17.7mg\;g^{-1}\;fw$ to $12.3mg\;g^{-1}\;fw$ and then remained unchanged. The absorbance of UV-absorbing compounds reached initially maximum at all wavelengths read. On the basis of this result, we analyzed total phenolics, anthocyanin and simple free phenolic acids. Anthocyanin and free phenolic acids responded sensitively with a steady increase during UV-B treatment, although anthocyanin contents declined highly after 3 hrs of treatment. Whereas, there is no alteration of total phenolics (as gallic acid equivalent) caused by UV-B. Free polyamine levels in leaves increased rapidly and highly when UV-B was treated. The most prominent changes in polyamine induction were putrescine and spermidine (+ 70 %) after 3 hrs and spermine (+ 150 %) after 6 hrs.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.29-36
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• 2007

Five phenolic compounds 1-5 were isolated for the first time from the exudate of geminating peanut (Arachis hypogaea). The structures were fully characterized by analysis of physical and spectral data. All isolated compounds were tested for antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical. Compounds 2, 3, and 5 exhibited a strong scavenging effect on DPPH (2: $IC_{50}\;=\;10.4\;{\um}M$, 3: $IC_{50}\;=\;45.2\;{\mu}M$, 5: $IC_{50}\;=\;5.0\;{\mu}M$), and ABTS (2: $IC_{50}\;=\;9.6\;{\mu}M$, 3: $IC_{50}\;=\;5.5\;{\mu}M$, 5: $IC_{50}\;=\;3.3\;{\mu}M$) radical activity, whereas these compounds had weak hydroxyl radical scavenging activity ($IC_{50}\;>\;200\;{\mu}M$). The total phenolic contents of the extracts using n-hexane, EtOAc, and n-BuOH were found to be 96.4-964.3 mg gallic acid equivalent per g dry material (GAE/g) and n-BuOH fraction showed the highest total phenolic content (964.3 mg GAE/g). These studies suggest that the exudate of geminating peanut may possess possible health related benefits to humans.

• Food Science and Preservation
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• v.21 no.2
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• pp.224-230
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• 2014

Brazil (Monte Alegro) and Ethiopia (Sidamo) coffee beans were roasted at three different roasting levels(light, medium, and dark), and were analyzed for color, total phenolic compound, caffeine, and chlorogenic acid contents. The total phenolic and caffeine contents remained unchanged during roasting. The chlorogenic acid levels of the Brazil and Ethiopia samples decreased with roasting. The antioxidant activities were measured using DPPH and ABTS. The radical scavenging activities of the light-roasted and dark-roasted coffee beans were similar. The flavor patterns of roasted coffee beans were analyzed using an electronic nose system based on gas chromatography. The data revealed that the flavor patterns of the roasted coffee beans could be separated via discriminant function analysis (DFA) method. The taste of the roasted coffee beans was analyzed using an electronic tongue system. The sourness and sweetness were decreased with roasting.

• Preventive Nutrition and Food Science
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• v.19 no.1
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• pp.40-48
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• 2014

Laver is one of the most consumed edible red algae seaweeds in the genus Porphyra. Laver is primarily prepared in the form of dried, roasted, and seasoned products. We investigated the total polyphenol and flavonoid contents of laver products, and evaluated the in vitro antioxidant properties of solvent extracts from commercially processed laver products. Significant differences in the concentration of phenolic compounds were found among differently processed laver. The total phenolic content for laver extracts ranged from 10.81 mg gallic acid equivalent (GAE)/g extract to 32.14 mg GAE/g extract, depending on extraction solvent and temperature. Laver extracts contained very few flavonoids (0.55 mg catechin equivalent/g extracts to 1.75 mg catechin equivalent/g extracts). 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), hydroxyl radical, and superoxide anion scavenging assays were used to determine the radical scavenging capacities of laver extracts. These assays revealed that the processing method and extraction condition affected the antioxidant potentials of laver. Antioxidant activity of dried laver, roasted laver, and seasoned laver increased in a concentration-dependent manner ($100{\sim}1,000{\mu}g/mL$). The radical scavenging activities of $37^{\circ}C$ and $100^{\circ}C$ water extracts were lower than that of a $37^{\circ}C$ 70% ethanol extract. The highest radical scavenging capacity was observed in the $37^{\circ}C$ 70% ethanol extracts of dried laver, roasted laver, and seasoned laver. Overall, these results support that notion that laver contains bioactive compounds, such as polyphenols and flavonoids, which may have a positive effect on health.

• Mycobiology
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• v.38 no.4
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• pp.295-301
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• 2010

We evaluated the antioxidant activity and tyrosinase inhibitory effects of Pleurotus ostreatus fruiting bodies extracted with acetone, methanol, and hot water. The antioxidant activities were tested against $\beta$-carotene-linoleic acid, reducing power, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, and ferrous chelating ability. Furthermore, phenolic acid and flavonoid contents were also analyzed. The methanol extract showed the strongest $\beta$-carotene-linoleic acid inhibition as compared to the other exracts. The acetone extract (8 mg/mL) showed a significantly high reducing power of 1.54 than the other extracts. The acetone extract was more effective than other extracts for scavenging on 1,1-diphenyl-2-picrylhydrazyl radicals. The strongest chelating effect (85.66%) was obtained from the acetone extract at 1.0 mg/mL. The antioxidant activities of the extracts from the P. ostreatus fruiting bodies increased with increasing concentration. A high performance liquid chromatography analysis detected seven phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, naringenin, hesperetin, formononetin, and biochanin-A in an acetonitrile and 0.1 N hydrochloric acid (5 : 1) solvent extract. The total phenolic compound concentration was $188{\mu}g$/g. Tyrosinase inhibition of the acetone, methanol, and hot water P. ostreatus extracts increased with increasing concentration. The results revealed that the methanol extract had good tyrosinase inhibitory ability, whereas the acetone and hot water extracts showed moderate activity at the concentrations tested. The results suggested that P. ostreatus may have potential as a natural antioxidant.

• Journal of Ginseng Research
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• v.37 no.3
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• pp.349-354
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• 2013

Dried ginseng (DG) is in fact the representing ginseng product in the worldwide market. Although it is made in various packages depending on the processing method, size and age of DG, basic scientific data reporting the chemical components are limited. In this study, 4-year-old curved ginseng (CG), one of the domestic DG products, was selected for further investigation. Eighty-six samples of 30 and 50 piece-grade CG, which are the most widely distributed in the market, were collected for 5 yr. Their major components, such as moisture, total sugar, acidic polysaccharides, total phenolic compounds, and saponins, were analyzed to figure out the standard quality characteristics. The moisture content of all CG samples was less than 15%. The total water-soluble sugar contents were 22.9% to 47.8% and 23.2% to 49.5% in the 30 and 50 piece-grade CG, respectively. The acidic polysaccharide contents were 3.6% to 6.7% and 2.9% to 6.9% in the 30 and 50 piece-grade CG, respectively. The total phenolic compound content was 0.4% to 0.5% in CG, regardless of the piece-grade. The crude saponin content, which represents the active component of ginseng, was over 2% in all samples. In 30 piece-grade CG samples, the contents of major ginsenosides, Rb1, Rf, and Rg1, were 2.2 to 4.7 mg/g, 0.4 to 1.3 mg/g, and 1.6 to 4.0 mg/g, respectively. The ginsenoside contents in 50 piece-grade CG samples were 2.1 to 3.9 mg/g (Rb1), 0.5 to 1.2 mg/g (Rf), and 1.3 to 3.4 mg/g (Rg1). Overall, since there were relatively high standard deviation and coefficient of variation in all the chemical component contents that were assessed, we found some difficulties in showing the CG standard chemical component characteristics by average, standard deviation, and other statistical analysis factors.