• Food Science and Preservation
• /
• v.31 no.1
• /
• pp.183-196
• /
• 2024

This study investigated the protective effect of the aqueous extract of Eucommia ulmoides leaves (AEEL) against high glucose-induced human colon epithelial HT-29 cells. The 2,2'-azino-bis (3-ethyl benzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activities, ferric reducing/antioxidant power (FRAP), and malondialdehyde (MDA) analyses indicated that AEEL had significant antioxidant activities. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that AEEL increased cell viability against high glucose-, H₂O₂-, and lipopolysaccharide (LPS)-induced cytotoxicity in HT-29 cells. Also, the 2'-7'-dichlorodihydrofluorescein diacetate (DCF-DA) assay indicated that AEEL decreased intracellular reactive oxygen species (ROS) against high glucose-, H₂O₂-, and lipopolysaccharide (LPS)-induced cytotoxicity in HT-29 cells. AEEL showed inhibitory activities against α-glucosidase and inhibited the formation of advanced glycation end products (AGEs). AEEL showed significant positive effects on the viability and titratable acidity of L. brevis. The high-performance liquid chromatogram (HPLC) analysis identified chlorogenic acid and rutin as the major compounds of AEEL. These results suggested that AEEL has the potential to be used as a functional food source to suppress blood glucose levels and protect the gut from high glucose-induced oxidative stress.

• Microbiology and Biotechnology Letters
• /
• v.51 no.3
• /
• pp.280-288
• /
• 2023

In strawberry farming, most parts of strawberry stems but the fruit have been dumped. Therefore, this study attempted to investigate the antioxidant and anti-inflammatory effects of strawberry stems which are thrown away after farming. For this, strawberry stem extracts were obtained, using hot water and 70% ethanol. First, total polyphenol contents of the hot water and ethanol extract were checked (265.4 ± 0.12 mg TAE/100 g, 503.88 ± 0.2 mg TAE/100 g). For analysis of antioxidant activities, electron donating ability (EDA) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity were measured. Both extracts increased in a dose-dependent fashion, and similar effects with vitamin C (control group) were confirmed. In terms of cell viability of the hot water and ethanol extracts of strawberry stems, 'RAW 264.7' was 99% or higher at 500 ㎍/ml. In addition, cell experiments were conducted at 50, 100 and 500 ㎍/ml where cell viability is above 99%. In terms of inhibition of the inflammatory mediator 'nitric oxide (NO)', the hot water and ethanol extracts of strawberry stems were 37.9% and 38.8% respectively, confirming the inhibition of NO production. To check anti-inflammatory activities, protein and mRNA expressions of 'iNOS' and 'COX-2' were measured, using RAW 264.7. Compared to the LPS group, the protein expression of the inflammatory mediators was inhibited in the hot water and ethanol extract-treated groups. The above results confirmed that the hot water and ethanol extracts of strawberry stems are valuable as natural substances with antioxidant and anti-inflammatory activities.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.38 no.1
• /
• pp.57-65
• /
• 2012

In the present study, the antioxidative properties, inhibitory activity on tyrosinase, and active components of Eriobotrya japonica (E. japonica) leaf extract were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract/fraction of E. japonica leaf was in the order 50 % ethanol extract ($22.625{\mu}g/mL$) < ethyl acetate fraction (6.75) < deglycosylated aglycone fraction (5.06). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of fraction/extracton ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescenceassay were investigated. $OSC_{50}$ of the ethyl acetate fraction, deglycosylated aglycone fraction, and ethanol extract were 0.75, 0.79, and $1.61{\mu}g/mL$, respectively. The cellular protective effects of E. japonica leaf extract on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The protective effects of extract/fraction of E. japonica leaf were increased in a in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). Especially, ${\tau}50$ of ethyl acetate fraction at concentrations of $10{\mu}g/mL$ and $50{\mu}g/mL$ showed the most protective effects at 390.8 min and 1471.5 min. The inhibitory effect ($IC_50$) on tyrosinase of E. japonica leaf extracts was higher than arbutin, known as a skin-whitening agent. The order of inhibitory effects was acetate fraction ($75.25{\mu}g/mL$) < 50 % extract (74.1) < deglycosylated aglycone fraction (43.35). TLC of the ethyl acetate fraction showed 7 bands (EJL 1 - EJL 7). HPLC of the aglycone fraction exhibited 2 peaks, kaempferol and quercetin. The amounts of kaempferol and quercetin were 53.7 and 46.3 %. respectively. Therefore, The amounts of kaempferol and its glucoside were a little bit higher than quercetin and its glucoside in E. japonica leaf extract. Accordingly, these findings suggest that extracts/fractions of E. japonica leaf can function as antioxidants in biological systems, especially skin exposed to UV radiation, and protect cellular membranes against ROS. Thus, the extract/fraction of E. japonica leaf may be used in novel functional cosmetics as antioxidants against skin photoaging.

• Applied Chemistry for Engineering
• /
• v.29 no.4
• /
• pp.452-460
• /
• 2018

This study was conducted to investigate the physiological activities of Houttuynia cordata extracts and fractions. H. cordata extracts were extracted with 50% ethanol and the ethyl acetate fractions were obtained from the extracts. Minimum inhibitory concentration (MIC) values of the ethyl acetate fraction for S. aureus and B. subtilis were $78{\mu}g/mL$ and $312{\mu}g/mL$, respectively, indicating the high activity against gram-positive bacteria. The free radical scavenging activity ($FSC_{50}$) for 1,1-diphenyl-2-picrylhydrazyl (DPPH) was higher in the ethyl acetate fraction with $12.00{\mu}g/mL$ compared to that of $27.15{\mu}g/mL$ for 50% ethanol extract. The total antioxidant activity ($OSC_{50}$) values for reactive oxygen species (ROS) produced in $Fe^{3+}-EDTA/H_2O_2$ system by a luminol-dependent chemiluminescence method were 2.91 and $0.983{\mu}g/ml$ for the 50% ethanol extract and ethyl acetate fraction, respectively. To investigate cellular protective effects on the HaCaT cell, the intracellular ROS scavenging activity was measured after UVB irradiation and the ethyl acetate fraction of H. cordata showed the activity in a concentration-dependent from $1.6{\mu}g/mL$ and a reduction rate of 54.3% at a maximum concentration of $12.5{\mu}g/mL$. Also, HaCaT cell protective effect against $H_2O_2$-mediated decreased the cell viability of the ethyl acetate fraction of H. cordata which significantly increased the cell viability from $0.8{\mu}g/mL$ and the maximum cell viability showed 86.9%. The ethyl acetate fraction of the H. cordata extracts was analyzed by TLC and HPLC. As a result, quercitrin, isoquercitrin, hyperoside, chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, rutin and afzelin were identified. From the above results, it was suggested that the extracts and fractions of H. cordata have a potential to be applied in the field of cosmetics as a natural antioxidant/preservative capable of protecting the cell membrane from the oxidative stress by eliminating ROS and exhibiting the antimicrobial effect.

• Journal of Life Science
• /
• v.14 no.1
• /
• pp.1-7
• /
• 2004

The root of Stnchys Sieboldif MIQ was extracted three times with methanol and extract was found to contain 3.02% of polyphenols and 1.97% of flavonoids. DPPH radical scavenging method, ferric thiocyanate method, and nitrite scavenging ability method were employed to investigate the constituents of the extract and to measure their activity on antioxidation. The fraction extracted by ethylacetate showed higher anti oxidation value than that of $\alpha-tocopherol$, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) at the same concentration. UV-VIS spectral data of the extract by ethylacetate that was isolated on a silica gel column proved adsorption maxima in the range of 280∼330 nm. The fraction ES-RS that has $\lambda_{max}(nm)$ of band 1, 325nm and band II, 289nm exhibitd the strongest activity on antioxidation. ES-R5 fraction showed similar pattern to flavones by the analysis of UV-VIS spectral data.

• Food Science and Preservation
• /
• v.22 no.5
• /
• pp.699-707
• /
• 2015

To improve the utilization of the domestic plant Salvia miltiorrhiza Bunge (Danshen), this study investigated changes in the physicochemical qualities of Danshen extracts obtained from low-temperature extraction using the enzymes amylase, cellulase, pectinase, and protease. Changes in the yield, pH, sugar content, and chromaticity were investigated. The changes were found to be highest in the amylase-treated extract with the following values: yield, 58.3%; pH, 6.04; sugar content, $5.97^{\circ}Brix$. With regard to antioxidant properties, Danshen extracts treated with amylase showed the highest DPPH and ABTS scavenging activities of 84.25% and 74.11% at 55 ppm. The total phenolic compound content was highest in the group subjected to enzyme treatment at $60^{\circ}C$. The salvianolic acid B level of the Danshen extract was the highest in the amylase-treated group, with a value of 3,002.6 mg/100 g. Cryptotanshinone level was the highest in the amylase- and protease-treated group with a value of 3.8 mg/100 g. Tanshinone I was the highest in the protease-treated group, with a value of 14.2 mg/100 g. The results showed that the indicator components of Danshen were detected as stable in the extracts after using amylase for low-temperature extraction; therefore, it would be possible to use Danshen industrially as a functional ingredient through mass production. Furthermore, the enzyme-treatment extraction could be utilized for a variety of natural products.

• Journal of Life Science
• /
• v.31 no.2
• /
• pp.229-236
• /
• 2021

This study was carried out to evaluate the antioxidant properties of the dried leaves and branches of Stewartia koreana Nakai. The dried leaf and branch of S. koreana were extracted with 70% ethanol at 80℃. The antioxidant activities of ethanol extracts of S. koreana leaf (EESL) and S. koreana branch (EESB) were analyzed. The total polyphenol contents in EESL and EESB were 162.57±0.9 mg of GAEs/extract g and 59.1±0.9 mg of GAEs/extract g, respectively. The flavonoid contents in EESL and EESB were 59.1±0.9 mg of QEs/extract g and 4.7±0.1 mg of QEs/extract g, respectively. EESL showed a better scavenging ability with DPPH and ABTS than EESB, at 0.4 mg/ml. Moreover, EESL were more effective according to ORAC values than EESL. The toxicity of EESL was investigated using a WST-1 assay on the human skin fibroblast cell line CCD-986sk. Therefore, EESL can be used as a potential source of functional, naturally-sourced material in cosmetics as well as food.

• Journal of Life Science
• /
• v.31 no.11
• /
• pp.1010-1018
• /
• 2021

Although varieties of silkworms, which have recently attracted attention as a health functional food, are being produced, studies on the differences in the functionality of different silkworm varieties are insufficient. Therefore, in this study, the antioxidant activities of different silkworm breeds bred in domestic farms were analyzed, and the potential for their cultivation as specialized varieties with excellent antioxidant function was investigated. To compare antioxidant activity, four varieties of silkworms, white Bakokjam, Golden silk, Yeonokjam, and Hanseongjam, were bred; water and ethanol extracts of these silkworms were prepared on the 3rd and 5th days of the 5th instar larval stage. The highest extraction yield was seen for the water extract from the Golden silk variety on the 3rd day of the 5th instar; the highest total phenolic compound and flavonoid contents were observed for the water extract (86.11±4.04 ㎍/mg GE) and 70% (v/v) ethanol extract (46.70±2.81 ㎍/mg QE). Bakokjam and Yeonokjam exhibited DPPH radical scavenging activity of up to 78% and showed the highest nitrite scavenging activity (85%) at pH 1.2. The maximum SOD-like activity of Yeonokjam was about 47%. Furthermore, 48 ㎍/ml of the Yeonokjam extract showed a reducing power of 0.7 abs, which was the best among the four varieties. Considering these results, the Yeonokjam (on the 3rd day of the 5th instar) had antioxidant activity and represents a silkworm cultivar that would be suitable for cultivation as a health food.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.5
• /
• pp.830-841
• /
• 2015

This study compared the physicochemical characteristics, proximate composition, taste compound and antioxidant properties of Sikhye prepared with pigmented rice. Proximate composition showed a significant difference depending on the type of pigmented rice except crude fat contents and pH, color was a significant difference depending on the type of pigmented rice. The highest brix degree was $15.07^{\circ}Brix$ in red and black rice Sikhye. Each highest value of reducing sugar and free sugar content showed milled rice and brown rice Sikhye. Titratable acidity and total acidity of the pigmented rice Sikhye were highest for black rice Sikhye, free sugar content were highest for green rice Sikhye. Analysis of their relative antioxidative properties indicated that black rice Sikhye had the highest total polyphenol, flavonoid, and anthocyanin content, the highest levels of DPPH radical scavenging ability, and the highest level of reducing power and ferric reducing ability of plasma scores. Principal component analysis suggested that black rice Sikhye had a strong association with antioxidant properties, brown and red rice Sikhye had the strongest association with the sweetness and unique flavor.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.11
• /
• pp.1717-1726
• /
• 2013

Fermentation characteristics and health functionalities of kimchi by inoculating kimchi lactic acid bacteria (LAB) starters were studied. We manufactured single LAB starter kimchi (Lactobacillus plantarum pnuK, Lactobacillus plantarum 3099K, Leuconostoc mesenteroides pnuK), mixed LAB starter kimchi (Lb. plantarum pnu/Leu. mesenteroides pnuK, Lb. plantarum 3099/Leu. mesenteroides pnuK) with inoculum size of $10^6$ CFU/g, as well as naturally fermented kimchi (NK), and fermented them for 6 days at $15^{\circ}C$. The pH and acidity of the early phase of fermentation were not different, but kimchi with the starters showed rapid changes in the pH and acidity from 2 days of fermentation. As the fermentation progressed, the level of total aerobic bacteria and Lactobacillus sp. increased similarly with or without Lb. plantarum (LP) inoculation. However, the level of Leuconostoc sp. was high in kimchi inoculated with Leuconostoc sp. starter. In the sensory evaluation test, kimchi with starters received higher overall acceptability scores than those of NK; mixed starter added kimchi earned the highest score. In DPPH and hydroxyl radical scavenging activity, kimchi with the starters exhibited higher activity than that of NK. In the MTT assay of HCT-116 and HT-29 human colon cancer cells, NK showed inhibition rates of 63.4 and 51.9%, but LPpnuK achieved 77.1 and 68.8%, respectively. This study showed that inoculating starters in kimchi increased in vitro antioxidant and anticancer activities, and single starter (LP) added kimchi revealed higher functionality than the kimchi with mixed starter. Kimchis with the starters effectively up-regulated the gene expressions of the pro-apoptotic gene of Bax, but down-regulated Bcl-2. They promoted expressions of p53 and p21, and suppressed expressions of inflammation-related genes, iNOS and COX-2, compared with NK. Taken together, it is expected that using starters may help manufacture kimchi with improved sensory quality and health functionality.