Antioxidant Activity of Aralia elata Seeds Fractions

Weicheng Hu,Myeong-Hyeon Wang 한국원예학회 2009 Horticulture, Environment, and Biotechnology Vol.50 No.3

Aralia elata is the edible vegetable and has been used for medicinal purposes. The present study investigated the in vitro antioxidant potential of dichloromethane (CH₂Cl₂), ethyl acetate (EtOAc), n-butanol (n-BuOH) and water (H₂O) fraction of 70% methanolic (MeOH) extract of A. elata seeds using different antioxidant tests, such as total phenolic content, 1,1-diphenyl-2-pricylhydrazyl (DPPH) radical-scavenging assay, hydroxyl-radical (ㆍOH) scavenging assay, reducing power assay, metal-chelating activity and lipid peroxidant assay. Among these fractions, EtOAc fraction exhibited higher antioxidant potency than other fractions in DPPH free radical-scavenging, hydroxyl radical-scavenging activity, reducing power assay and lipid peroxidant assay. It was concluded that the A. elata seeds fractions obtained from 70% MeOH extract are highly suitable for medical application due to their efficient antioxidant properties.

Antioxidant and Anti-inflammatory Activity of Kalopanax pictus Leaf

Hu, Weicheng,Heo, Seong-Il,Wang, Myeong-Hyeon The Korean Society for Applied Biological Chemistr 2009 Applied Biological Chemistry (Appl Biol Chem) Vol.52 No.4

Kalopanax pictus is a deciduous tree used in traditional medicine. The leaves have been consumed as a vegetable in Korea. In this study, we examined the antioxidant and anti-inflammatory capacity of the extracts from K. pictus leaves in vitro using hydroxyl radical scavenging assay, DNA nicking assay, metal chelating assay, reducing power assay, DPPH free radical scavenging assay, and nitric oxide inhibition assay. The effect of the hot water extract was stronger than that of the methanolic and ethanolic extracts in all of the assays. Moreover, the total phenolic contents in the extracts were measured by spectrophotometry. Meanwhile, a regression analysis revealed a correlation coefficient between the content of phenolics and antioxidant activity. Overall, our data suggest that K. pictus leaves possess significant antioxidant properties.

Antioxidant Activities of Various Extracts of Hovenia dulcis Thunb Fruits

Hu, Weicheng,Lee, Kab-Yeon,Wang, Myeong-Hyeon The Plant Resources Society of Korea 2010 한국자원식물학회지 Vol.23 No.3

Hovenia dulcis Thunb fruits were successively extracted with hot water, water, methanol, ethyl acetate, and chloroform. The crude extracts were investigated for potential antioxidant by measuring scavenging against DPPH free radicals, reducing power, superoxide radicals, and protection of protein damage and cultured cells from a lethal dose of hydrogen peroxide ($H_2O_2$). In all chemical assays used, the hot water extract of H. dulcis fruits, which contained $61.14{\pm}2.57$ (Tannic acid mg/g extract, n=3) of total phenolic compounds contents exhibited highest activity in in vitro models of DPPH free radical scavenging activity, reducing power assay, superoxide radical scavenging activity and protection of protein damage. In addition, the hot water extract protected cultured RAW 264.7 macrophages from a lethal dose of $H_2O_2$ and reduced reactive oxygen species level in RAW 264.7 cells.

Chemical Composition, Antioxidant and Cytoprotective Activities of Lotus Receptacle

Weicheng Hu,Gongcheng Wang,Ting Shen,Yuning Wang,Boran Hu,Xinfeng Wang,Lei Wu,Pengxia Li,Lilian Ji 한국원예학회 2015 Horticulture, Environment, and Biotechnology Vol.56 No.5

The nutritional composition (ash, protein, fat, crude fiber, and carbohydrate) and antioxidant activity of lotus receptacles (LRs) were studied. The LRs contained 88.25% carbohydrates, 22.90% crude fiber, 5.79% crude ash, 0.77% crude protein content, and 5.19% crude lipid on a dry weight basis. The ethanolic extract of lotus receptacle (ELR) exerted strong scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, hydroxyl radical (•OH), superoxide anion (O2-), and hydrogen peroxide (H2O2), as well as high reducing power. ELR pretreatment effectively elevated cell viability and decreased malondialdehyde (MDA) levels in H2O2-treated RAW 264.7 cells. Additionally, ELR had high phenolic and flavonoid contents with values of 318.15 mg gallic acid equivalent/g and 239.06 mg rutin equivalent/g, respectively. Moreover, the bioactivity-guided study of ELR resulted in the isolation and identification of quercetin-3-O-β-D-glucopyranoside (QOG), a dietary flavonoid. QOG exhibited strong DPPH free radical scavenging activity, with an IC50 value of 24.26 μM; docking studies revealed that QOC formed one hydrogen bond with LYS263 in the active site, suggesting it is, in part, responsible for the free activity of LR.

Free Radical Scavenging Activity and Protective Ability of Methanolic Extract from Duchesnea indica Against Protein Oxidation and DNA Damage

Hu, Weicheng,Shen, Wei,Wang, Myeong-Hyeon The Korean Society of Food Science and Nutrition 2009 Preventive Nutrition and Food Science Vol.14 No.4

The antioxidant potency of methanolic extract of Duchesnea indica (MDI; Indian strawberry) was investigated by employing various established in vitro systems, such as total phenolic content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, reducing power assay, metal chelating assay, superoxide radical scavenging activity and protective ability of DNA damage and protein oxidation. MDI inhibited metal chelating by 75.57% at 2 mg/mL, scavenged 50% DPPH free radical at 29.13 ${\mu}$g/mL, and eliminated approximately 46.21% superoxide radical at the concentration of 1 mg/mL. In addition, MDI showed strong ability on reducing power, DNA damage protection and protein oxidation protection. Overall, results suggested that MDI might be beneficial as a potent antioxidant and effectively employed as an ingredient in food applications.

Antioxidant and Cytoprotective Activity of Castor-aralia (Kalopanax pictus) Leaves

Weicheng Hu,Seong-Il Heo,Myeong-Hyeon Wang 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.6

The present study was to investigate the in vitro antioxidant potential of hot water extract and its fractions from dichloromethane (CH₂Cl₂), ethyl acetate (EtOAc), n-butanol (n-BuOH), and water (H₂O) of castor-aralia (Kalopanax pictus) leaves using different antioxidant tests. Among these crude extract and fractions, EtOAc fraction exhibited higher antioxidant potency than others in 1,1-diphenyl-2-pricylhydrazyl (DPPH) free radical scavenging, reducing power assay, and reactive oxygen species (ROS) scavenging activity. However, CH₂Cl₂ fraction showed higher hydroxyl radical scavenging and DNA damage protective activity. This work demonstrates the potential of castor-aralia leaves as antioxidant functional food ingredients.

Antioxidant and Antiproliferative Activities of Methanolic Extract from Celandine

Weicheng Hu,Myeong-Hyeon Wang 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.1

Celandine (Chelidonium majus, family Papaveraceae) is an herb used extensively in traditional Korean medicine. To investigate its antioxidant and antiproliferative activities, the methanolic extract of celandine was introduced. The antioxidant properties of the extract were tested using various in vitro systems, including hydroxyl radical scavenging assay, DNA damage protection assay, 1,1-diphenyll-2-2-pricylhydrazyl (DPPH) free radical scavenging activity, metal chelating activity, and reducing power assay. The extract exhibited stronger antioxidant activity (IC??=7.92 ㎍/㎖) against hydroxyl radicals in the Fenton system than butylated hydroxyanisole (IC??=51.46 ㎍/㎖) and α-tocopherol (IC??=67.48 ㎍/㎖). Likewise, damage to the plasmid pBR 322 induced by hydroxyl radicals was found to be protected by the extract at a concentration of 400 ㎍/㎖. Cellular proliferation and the induction of apoptosis were also examined by a cellular proliferation assay, flow cytometry, and mRNA expression analysis. Taken together, the extract significantly inhibited the growth of HT-29 cells in a concentration- and time-dependent manner, and gradually increased both the proportion of apoptotic cells and the expression of caspase-3. Overall, our research suggests that celandine possesses antioxidant and antiproliferative properties.

The antidiabetic effects of an herbal formula composed of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng in the streptozotocin-induced diabetic rats

Weicheng Hu,Jin-Hee Yeo,Yunyao Jiang,Seong-Il Heo,Myeong-Hyeon Wang 한국영양학회 2013 Nutrition Research and Practice Vol.7 No.2

A folk prescription consisting of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng has been used in the treatment of diabetes mellitus. The aim of the present investigation was to evaluate the antidiabetic effects of the herb formula extract (HFE) composed of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng in the streptozotocin (STZ)-induced diabetic rats. The HFE was mixed in the food supply of the healthy and STZ-induced diabetic male Sprague-Dawley rats, and its effects on the body weight, water and food intake, hyperglycemia, hypolipidemic and islet structure were studied. The treatment of the rats with STZ for 6 weeks resulted in marasmus, polydipsia, polyphagia, hyperglycemia and hypoinsulinemia. In addition, the diabetic rats showed an apparent decrease in the insulin immunoreactivity and the number of β-cells in the pancreas. The addition of the HFE to the rats’ food supply significantly lowered the serum glucose and the serum triglycerides level and preserved the normal histological appearance of the pancreatic islets. These results indicate that the HEF have a strong antidiabetic potential along with the significant hypoglycemic and hypolipidemic effects, which may be applicable in the pharmaceutical industry.

Diarylheotanoid from Alnus hirsuta Improves Glucose Metabolism via Insulin Signal Transduction in Human Hepatocarcinoma (HepG2) Cells

Weicheng Hu,왕명현 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.1

Alnus hirsuta is a deciduous, broad-leaved tree that thrives in damp locations, and the bark of the Alnus species has been used in traditional oriental medicine as a remedy for hemorrhage, fever, diarrhea, and alcoholism. Two diarylheptanoids, 1,7-bis-(3,4-dihydroxyphenyl)-heptane-3-one-5-O-β-D-xylopyranoside (Compound I) and 1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-β-D-xylopyranoside (Compound II), were isolated from the stem bark of A. hirsuta. In the present study, the investigations of two diarylheptanoids on insulin signaling were performed in insulin-responsive human hepatocarcinoma (HepG2) cells co-treated with high glucose. As the results, the insulin metabolic effect of glucose uptake was inhibited by high glucose. However, treatment of Compound I enhanced the glucose uptake ability in HepG2 cells, whereas, Compound II did not affect glucose incorporation noticeably. In addition,we demonstrated that treatment of HepG2 cells with Compound I improved the mRNA expression level of insulin receptor (IR) and insulin receptor substrate-1 (IRS-1).

Biological Activity and Inhibition of Non-Enzymatic Glycation by Methanolic Extract of Rosa davurica Pall. Roots

Weicheng Hu,Woong Han,Yunyao Jiang,Myeong-Hyeon Wang,Young-Mee Lee 한국식품영양과학회 2011 Preventive Nutrition and Food Science Vol.16 No.3

The methanolic extract of Rosa davurica Pall. roots exhibited strong antioxidant activity in a 1,1-diphenyl-2- picryl-hydrazyl (DPPH) radical scavenging assay and was found to be a dose-dependent inhibitor of non-enzymatic formation of advanced glycation end products (AGEs), which are relevant to diabetes complications. HPLC-diode array detector (DAD) analysis of the R. davurica Pall. root extract led to the identification of four compounds: hydrocaffeic acid, catechin, epicatechin, and ellagic acid. Catechin was present in the largest amount and exhibited high antiglycation activity. A CYP3A4 assay was used to investigate potential interactions between drugs and the extract, and results suggest that the R. davurica Pall. root extract had moderate potential for interfering with drug metabolism. The R. davurica Pall. extract did not display anti-inflammatory activity on the level of that for tumor necrosis factor-α (TNF-α) in a lipopolysaccharide (LPS)-stimulated macrophage assay; however, the extract did exhibit low to moderate immunostimulatory activity in a pro-inflammatory macrophage assay. Therefore, we conclude that R. davurica Pall. root is a promising anti-AGE agent with low to moderate risks of associated inflammation or drug interaction.