• Korean Journal of Pharmacognosy
• /
• v.38 no.4
• /
• pp.358-362
• /
• 2007

From the EtOAc fraction of the MeOH extract of Ulmus davidiana, (-)-catechin (1), (-)-catechin-7-O-${\beta}$-D-apiofuranoside (2), and (-)-catechin-7-O-${\beta}$-D-xylopyranoside (3) were isolated and characterized on the basis of $^1H-and\;^{13}C-NMR$, and FABMS spectral data. Compounds 1-3 showed more strong reducing power activities than ${\alpha}-tocopherol$, a positive control.

• Food Science and Preservation
• /
• v.17 no.4
• /
• pp.541-546
• /
• 2010

Wild-garlic (Allium victorialis L.) is a perennial plant found in worldwide and has been considered as a favorite vegetable due to its particular smell and taste. However, the study of biological activity of wild-garlic and the development of processed food are in rudimentary. In this study, we evaluated several biological activities, including antioxidant, antimicrobial, and inhibitory activities against human thrombin, $\alpha$-amylase and $\alpha$-glucosidase, of Ulrung wild-garlic. Analysis of the composition showed that Ulrung wild-garlic is nutritive although it is perishable. The color of fresh juice was stably maintained during 10 days-storage at $4^{\circ}C$, but rapidly discolored by heat treatment at $70^{\circ}C$ for 1 h. During heat treatment, the contents of total sugar and total polyphenol were decreased to 75% and 50%, respectively, and acidity was increased from 0.069% to 0.111%. In a while, the brix, reducing sugar, and total flavonoids showed minor changes. The fresh juice showed strong DPPH scavenging activity, reducing power and antibacterial and antifungal activity, but the heat-treated juice lost the antioxidant and antimicrobial activities. The inhibitory activities against human thrombin and $\alpha$-amylase and $\alpha$-glucosidase was negligible in both fresh juice and heat-treated juice. These results suggested that the antioxidant and antimicrobial components in wild-garlic are heat-liable and volatile. Based on our results, we propose non-heat treatment products for processed wild-garlic, for example, fresh juice-added beverage or fermented liquors using wild-garlic.

• Natural Product Sciences
• /
• v.28 no.3
• /
• pp.143-152
• /
• 2022

In our study, sixteen known phenolic compounds, including quercetin (1), methyl gallate (2), caesalpiniaphenol C (3), 8S,8'S,7'R-(-)-lyoniresinol (4), 7,3',5'-trihydroxyflavanone (5), sappanchalcone (6), sappanone A (7), taxifolin (8), fisetin (9), fustin (10), (+)-catechin (11), brazilin (12), 3,4,5-trimethoxyphenyl β-ᴅ-glucopyranoside (13), 1-(2-methylbutyryl)phloroglucinol-glucopyranoside (14), (+)-epi-catechin (15), and astragalin (16) and one mixture of two conformers of protosappanin B (17/18) were isolated from the stems of Caesalpinia decapetala var. japonica. Their structures were elucidated based on a comparison of their physicochemical and spectral data with those of literature. To the best of our knowledge, this represents the first isolation of compounds 3, 4, 8, 9, and 10 from C. decapetala and compounds 13 and 14 from the Caesalpinia genus. All the isolated compounds were evaluated for their inhibitory effect against the α-glucosidase enzyme. Among them, two flavonols (1 and 9), one chalcone (6), and one homoisoflavanone (7) exhibited an inhibitory effect on α-glucosidase action with an IC₅₀ range value of 5.08-15.01 μM, stronger than that of the positive control (acarbose, IC₅₀ = 152.22 μM). Kinetic analysis revealed that compounds 1 and 9 showed non-competitive α-glucosidase inhibition, while the inhibition type was mixed for compounds 6 and 7.

• Food Science and Preservation
• /
• v.24 no.3
• /
• pp.483-489
• /
• 2017

Phloridzin is a predominant member of the chemical class of dihydrochalcones and mainly found in apple. The biological activity of phloridzin treated with dielectric barrier discharge (DBD) plasma was evaluated to investigate whether exposure to plasma can be used as a tools to enhance the biological activity of natural resources. DBD plasma treatment of phloridzin was carried out for three different exposure times. The antioxidant effects of degraded phloridzin for different reaction time were evaluated via radical scavenging assay using DPPH radical. In addition, the anti-diabetic and anti-obesity properties of the degraded phloridzin were measured based on ${\alpha}$-glucosidase and pancreatic lipase inhibitory activities. Phloridzin treated for 60 min showed significantly higher radical scavenging, ${\alpha}$-glucosidase and pancreatic lipase inhibitory activities compared to the tested positive controls. Degradation of phloridizin induced by DBD plasma might be responsible for enhancing the biological activity of phloridizin.

• Preventive Nutrition and Food Science
• /
• v.16 no.1
• /
• pp.29-36
• /
• 2011

The purpose of this study was to investigate the phytochemical contents and biological activities, including $\alpha$-glucosidase inhibitory activity and antioxidant activity, from the fruits of Elaeagnus multiflora using different solvent systems. The 50% ethanol extract of this species showed the most potent $\alpha$-glucosidase inibitory activity (88.5%) at a concentration of 1 mg/mL. Moreover, this extract also displayed the strongest antioxidant activity in each assay, showing 96.3% in DPPH scavenging activity, 98.2% in ABTS scavenging activity, and 2.5% in reducing power. The highest total phytochemical contents, including flavan-3-ols, phenolic acids, and flavonoids, were observed in the 50% ethanol extract. Interestingly, flavan-3-ols (3.150 mg/g) were detected at a significantly higher total content than those of phenolic acids (0.380 mg/g) and flavonoids (not detected). Additionally, the contents of individual phytochemicals showed remarkable differences, especially the epicatechin gallate (2.008 mg/g) and gallic acid (0.099 mg/g), which were the predominant constituents of each phytochemical type. Therefore, our results suggest that the 50% ethanol extract of E. multiflora fruits has strong biological activities, which are correlated with high phytochemical contents.

• Journal of Food Hygiene and Safety
• /
• v.13 no.1
• /
• pp.20-23
• /
• 1998

The objective of this study was to evaluate the bifidogenic effect and a-glucosidase inhibitory effect of artificially cultured Phellinus linteus. The water extract of P. linteus promoted the growth of Bifidobacterium breve as well as the decrease of final pH in the media culturing intestinal bacteria. The growth of lactic acid bacteria inhibited effectively the bacterial enzymes, ${\beta}-glucosidase,\;{\beta}-glucuronidase$ and tryptophanase, of intestinal bactetria. The water extract of P. linteus inhibited maltase, sucrase and ${\alpha}-amylase$ of rat intestine.

• Preventive Nutrition and Food Science
• /
• v.16 no.3
• /
• pp.236-241
• /
• 2011

Allium victorialis L. (A. victorialis) is a very popular vegetable in Korea. The most commonly used parts of this vegetable are the bulbs and young leaves. To determine if the mature leaves have any beneficial properties, we investigated antioxidant, anti-${\alpha}$-glucosidase, anti-inflammatory, and anticancer activities of water and ethanol extracts from A. victorialis. Antioxidant activity was evaluated by measuring total phenolic content, DPPH and superoxide radicals scavenging activities. The water extract from A. victorialis ($W{\cdot}A$. victorialis) exhibited higher antioxidant ability than the ethanol extract ($E{\cdot}A$. victorialis). Moreover, the water extract showed strong inhibitory effect on ${\alpha}$-glucosidase. On the other hand, the ethanol extract had greater anti-inflammatory activity on murine macrophage cells (RAW 264.7) and greater anticancer activities against human colon cancer cells (HT-29). These results suggest that mature leaves from E·A. victorialis may have health-enhancing effects.

• Korean Journal of Medicinal Crop Science
• /
• v.25 no.3
• /
• pp.139-145
• /
• 2017

Background: Invasion of these invasive plants in the ecosystem threatens the habitat of endemic species, reduces biodiversity, and causes a disturbance in the ecological system. Hypochaeris radicata L. (Asteraceae), the most invasive plant in Korea, particularly in Jeju Island, invades farmlands, and autochthonous forests, resulting in the establishment of monocultures and modification of the ecosystem structure. Methods and Results: In this study was, we evaluated the biological activity of 70% ethanolic extracts from different parts of Hypochaeris radicata L. The biological activities of 70% ethanolic extracts of different parts, such as flower, leaf, stem, and root, of H. radicata were investigated. The total polyphenol content was highest in flower extracts ($50.82{\pm}3.16mg{\cdot}QE/g$). In addition, the highest flavonoid content was observed in flower extract ($15.19{\pm}2.03mg{\cdot}QE/g$). The flower extract of H. radicata exhibited stronger DPPH radical-scavenging activities, ABTS radical scavenging activities, and reducing power than the other parts. The flower extract of H. radicata was observed to have the highest tyrosinase and ${\alpha}-glucosidase$ inhibitory activities. Conclusions: The flower extracts of H. radicata exhibited remarkable antioxidant activity as well as tyrosinase and ${\alpha}-glucosidase$ inhibitory effects. These activities might be related to the phenolic compounds present in the H. radicata flower extract.

• The Korean Journal of Mycology
• /
• v.40 no.4
• /
• pp.296-298
• /
• 2012

In this study, the biological activities of 33 kinds of wild mushroom methanol extracts were investigated. Boletellus elatus showed the greatest fibrinolytic activity (1.08 plasmin units/mL) in a fibrin plate assay, and the activity of Heterobasidion insulasis was 0.89 plasmin units. The thrombin inhibitory activities of Boletellus elatus and Heterobasidion insulasis were 93.32% and 93.69%, respectively. In a ${\alpha}$-glucosidase inhibitory activity test, Laccaria amethystina showed the greatest inhibitory activity at 81.25%. The antioxidative activities of Gomphus sp. and Geastrum lageniforme were 91.37% and 90.42%, respectively. Since Boletellus elatus and Heterobasidion insulasis have strong fibrinolytic and thrombin inhibitory and antioxidative activities, the two mushrooms can be used as material for the development of biofunctional foods for cardiovascular diseases.

• Journal of Life Science
• /
• v.27 no.11
• /
• pp.1262-1268
• /
• 2017

Lemon myrtle (Backhousia citriodora), a plant in the Myrtaceae family, is native to the semitropical rain-forests of Queensland and is presumably the most commercialized native spice. In Australian thousands of lemon-myrtle trees are under tillage. This study was carried out to investigate the alcohol metabolism, hepatoprotective effects and antidiabetic, tyrosinase inhibitory activity of hot-water (LMW) and 80% ethanol (LME) extracts from lemon-myrtle leaves. The alpha-glucosidase (${\alpha}$-glucosidase) inhibitory activities of the LMW and LME extracts were 7.66% and 40.29% at 1 mg/ml (p<0.05), respectively. The tyrosinase inhibitory activity of the LME extract was about 38.26 % at 1 mg/ml. The effects the LMW and LME extracts had on alcohol-metabolizing activities were determined by measuring the generation of reduced nicotinamide-adenine dinucleotide (NADH) by acetaldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH). The ADH activities of the LMW and LME extracts significantly increased in a dose-dependent manner and were about 154.40% and 192.03% at 1 mg/ml, respectively (p<0.05). The ALDH activities of the LMW and LME extracts also significantly increased in a dose-dependent manner and were about 151.14% and 192.34% at 1 mg/ml, respectively (p<0.05). At $100{\mu}g/ml$, the LMW and LME extracts showed significant protective effects against tacrine-induced cytotoxicity in Hep G2 cells. The results suggested that Backhousia citriodora leaf extracts have the potential to be significant sources for natural health products.