Structural Evidence for Antihypertensive Effect of an Antioxidant Peptide Purified from the Edible Marine Animal Styela clava.

This study investigated the antihypertensive effects of an antioxidant peptide, Leu-Trp-His-Thr-His (LWHTH), purified from Styela clava peptic hydrolysate, to assess the bioactivity of the peptide and verify the value of S. clava as a health-promoting food. Also, the study presented structural evidence for the effects of LWHTH. The inhibitory effect of LWHTH on angiotensin I-converting enzyme (ACE) was assessed using enzyme reaction methods and the simulation methods in computational space. LWHTH inhibited ACE with an IC50 value of 16.42 ± 0.45 µM. The LWHTH structure was stable, and its ACE inhibitory effect was retained under simulated gastrointestinal conditions. In silico simulations revealed that LWHTH binds the active site of ACE, with residues LW making the ACE-LWHTH complex stable and residues HTH making the complex strong. Furthermore, LWHTH significantly reduced blood pressure in spontaneously hypertensive rats. These results demonstrate that LWHTH has the potential to be a healthy functional food with antihypertensive effects. Therefore, S. clava consumption may be beneficial for human health.

Investigation on preferably oriented abnormal growth of CdSe nanorods along (0002) plane synthesized by henna leaf extract-mediated green synthesis.

The theme of this work is to highlight the significance of green plant extracts in the synthesis of nanostructures. In asserting this statement, herein, we report our obtained results on the synthesis of hexagonal CdSe nanorods preferably oriented along (0002) plane through henna leaf extract-mediated reaction along with a discussion about the structural, morphological and optical properties of the synthesized nanorods. The possible mechanism for the synthesis of CdSe nanorods was explored. The formation of nanorods along (0002) plane was confirmed by the relatively high intensity of the (0002) peak in X-ray diffraction pattern. To account for the experimentally realistic condition, we have calculated the surface energies of hexagonal CdSe surface slabs along the low indexed (0002), [Formula: see text] and [Formula: see text] plane surfaces using density functional theory approach and the calculated surface energy value for (0002) surface is 802.7 mJ m-2, which is higher than [Formula: see text] and [Formula: see text] surfaces. On realizing the calculated surface energies of these slabs, we determined that the combination of [Formula: see text] and [Formula: see text] planes with lower surface energies will lead to the formation of CdSe nanorods growth along (0002) orientation. Finally, we argue that the design of new greener route for the synthesis of novel functional nanomaterials is highly desired.

Anti-oxidant and anti-adipogenic effects of acorn (Quercus acutissima CARR.) shell extracts via regulation of wnt signaling in 3T3-L1 cells.

Acorn (Quercus acutissima CARR.) is a nut from the Fagaceae family that has been used in traditional medicine for many years. However, shells from acorns are regarded as a by-product and are mostly discarded. Anti-adipogenic activities of acorn shells were investigated using 3T3-L1 cells and methanol shell extracts (AE-M). AE-M demonstrated Cu2+-chelation activities and anti-oxidant activities via reduction of oxidative stress levels induced using AAPH. Six days after adipocyte differentiation, 50 and 100 µg/mL AE-M completely suppressed 3T3-L1 adipogenesis and the anti-adipogenic effect was stronger than for the positive control 50 µM quercetin. Treatment with AE-M in 3T3-L1 cells reduced mRNA expression levels of adipogenic genes. AE-M-inhibition was found in pre-adipogenic, early, and intermediate stages of adipogenesis in 3T3-L1 cells. The Wnt/ß-catenin signaling pathway is required for AE-M-inhibition of 3T3-L1 adipogenesis.

Neuroprotective activity of Viola mandshurica extracts on hydrogen peroxide-induced DNA damage and cell death in PC12 cells.

This study was conducted to examine the neuroprotective effects of acetone extracts from Viola mandshurica (VME). The effect of VME on hydrogen peroxide (H(2)O(2))-induced DNA damage in PC12 cells was evaluated by the comet assay where VME (100 and 250 microg/mL) was a dose-dependent inhibitor of DNA damage induced by 500 micromol/L of H(2)O(2). The protective effect of VME against H(2)O(2)-induced oxidative damage on PC12 cells was investigated by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] reduction assay and lactate dehydrogenase (LDH) release assays. After 3 h of cell exposure to 500 micromol/L of H(2)O(2), a marked reduction in cell survival was observed. However, the reduction was significantly prevented by 100 and 250 microg/mL of VME. H(2)O(2) also induced severe apoptosis of the PC12 cells, which was indicated by Hoechst 33342 staining. Interestingly, the H(2)O(2)-stressed PC12 cells that were incubated with 100 and 250 microg/mL of VME had greatly suppressed apoptosis. The results suggest that VME could be a new antioxidant candidate against neuronal diseases.

Antioxidative and antigenotoxic activity of extracts from cosmos (Cosmos bipinnatus) flowers.

The Cosmos bipinnatus has been used in a traditional herbal remedy for various diseases such as jaundice, intermittent fever, and splenomegaly. The present study describes the preliminary evaluation of antioxidant activities and antigenotoxic effect of Cosmos bipinnatus flowers according to four different colors (white, pink, orange, and violet). The antioxidants properties were evaluated by determining TPC, DPPH RSA, ABTS RSA, and RP. The highest TPC of methanolic CFE (at concentration of 1 mg/ml) showed in violet colored CF (1,013 microM), and IC(50) of DPPH RSA, ABTS RSA, and RP were also the lowest in violet colored CFE with values of 0.61, 1.48, and 0.82 mg/ml, respectively. The antigenotoxic effect of the CFE on DNA damage induced by H(2)O(2) in human leukocytes was evaluated by Comet assay. Pretreatments with CFE produced significant reductions in oxidative DNA damage at the concentration of 500 microg/ml, except for violet colored CFE. The ED(50) value of white colored CFE has shown the highest inhibition (0.40 mg/ml) on H(2)O(2) induced DNA damage, followed by orange > pink > violet color. These results suggested that Cosmos bipinnatus has significant antioxidant activity and protective effect against oxidative DNA damage.

Effect of storage in juice with or without pulp and/or calcium lactate on the subsequent survival of Escherichia coli O157:H7 in simulated gastric fluid.

A study was conducted to evaluate the effect of storing Escherichia coli O157:H7 in fruit or vegetable juices with or without pulp and/or calcium lactate, on the bacterial resistance to a simulated gastric fluid (SGF, pH 1.5). Apple, carrot, orange, and tomato juices containing pulp or freed from pulp by filtration were used in this study. Calcium lactate at about 1.4 g/l was added to juices to obtain calcium supplemented juices. Juices with or without pulp and/or calcium lactate were inoculated with E. coli O157:H7 and then were stored at 7 degrees C for 0, 1, 2, or 4 days. The acid resistance of cells stored in juices with or without pulp and/or calcium lactate was determined by incubating in SGF for 90 or 240 min at 37 degrees C. Cells stored in apple juice for 4 days, carrot juice for 2 days, and orange juice for 4 days with pulp only had greater acid resistance, while all cells stored in tomato juice with pulp had greater acid resistance than cells stored in juice without pulp. The D-values of cells stored in supplemented apple and orange juices with calcium lactate declined 1.7-3.5 fold, whereas D-values of cells stored in supplemented tomato juice decreased by about 1.4-fold when compared to cells stored in juice without calcium lactate after exposure in SGF. These results indicate that storing E. coli O157:H7 in juices with pulp had little or no effect on the acid resistance of cells during subsequent exposure in SGF. Calcium lactate supplemented into juices could dramatically decrease the ability of E. coli O157:H7 to survive in SGF, possibly reducing the risk of foodborne illness by juice products.

Antioxidative and anticancer activity of extracts of cherry (Prunus serrulata var. spontanea) blossoms.

Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 microg/ml) showed the highest total phenol content (104.30 microM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE on DNA damage induced by H(2)O(2) in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by 200 microM of H(2)O(2), methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 microg/ml showed 38.8% inhibition against growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive materials.

Application of far-infrared irradiation in the manufacturing process of green tea.

Seven kinds of green tea leaves were manufactured with far-infrared (FIR) irradiation, and the physicochemical characteristics of the green tea were determined. Appropriate FIR irradiation during the manufacturing process significantly increased the polyphenolic content of green tea. FIR irradiation at 90 degrees C for 10 min, replacing the roasting step, and of the fully processed green tea leaves (GTP3) increased the total phenol content of green tea from 475.6 to 811.1 mg/g and the total flavanol content from 175.7 to 208.7 mg/g, as compared to the control. Epigallocatechin and epigallocatechin gallate increased from 57.68 and 9.60 mg/g in a nonirradiated control to 89.88 and 16.33 mg/g in GTP3, respectively. Ascorbic acid, caffeine, and nitrite scavenging activities were also increased in GTP3. However, the overall color change of GTP3 was negligible. These results indicate that the chemical properties of green tea are significantly affected by FIR irradiation at specific stages of the manufacturing process of green tea leaves and that this FIR irradiation results in high-quality green tea.

Effect of heat treatment on the antioxidative and antigenotoxic activity of extracts from persimmon (Diospyros kaki L.) peel.

Heat treatment of persimmon peel (PP) increased the antioxidative activity of the 70% ethanolic extract (EE) and water extract (WE) from PP. EE and WE both prevented H2O2-induced DNA damage to human peripheral lymphocytes. The antioxidative and antigenotoxic activities of the PP extracts were significantly affected by heating.

Antioxidant activity of far-infrared radiated rice hull extracts on reactive oxygen species scavenging and oxidative DNA damage in human lymphocytes.

The antioxidant activities of methanolic extracts of far-infrared irradiated rice hull (FRH) and non-irradiated intact rice hull (IRH) were determined. The antioxidant effects against reactive oxygen species (ROS) were evaluated by measuring scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide, hydrogen peroxide (H2O2), and nitric oxide radical and capacity for chelating metals. Except for H2O2 scavenging activity, FRH showed higher scavenging activity than IRH; for example, the 50% inhibitory concentration (mg/mL) values for DPPH radical scavenging of FRH and IRH were 0.067 and 0.085, respectively, as compared with 0.362 and 0.012 for butylated hydroxytoluene and alpha-tocopherol, respectively. The effect of rice hull extract on DNA damage induced by H2O2 in human lymphocytes was also evaluated by comet assay. The protective effect of rice hull extract increased as its concentration increased from 12.5 to 50 microg/mL, as indicated by DNA strand breakage decreasing from 38% to 22% with FRH and from 49% to 28% with IRH as compared with H2O2-treated positive controls. When human lymphocytes were post-incubated with rice hull extract for 30 minutes after exposure to H2O2, the protective ability of the rice hulls remained unchanged. These results suggest that methanol extracts of rice hulls possess significant ROS scavenging and metal chelating activities and protective effect against oxidative DNA damage.

Effect of far-infrared irradiation on catechins and nitrite scavenging activity of green tea.

The processed green tea leaves were irradiated by far-infrared (FIR) at eight temperatures (80, 90, 100, 110, 120, 130, 140, and 150 degrees C) for 10 min. After FIR irradiation, green teas were prepared by soaking the leaves in boiling water, and the physicochemical characteristics of the green tea were determined. FIR irradiation at 90 degrees C increased total phenol contents of green tea from 244.7 to 368.5 mg/g and total flavanol contents from 122.0 to 178.7 mg/g, compared with non-irradiated control. FIR irradiation also significantly affected the amounts of epigallocatechin and epigallocatechin gallate. Nitrite scavenging activity also increased with increasing FIR irradiation until the temperature reached 110 degrees C. However, the overall color changes of green tea irradiated with FIR at 90 and 100 degrees C were negligible. These results indicate that the chemical quality of green tea is significantly affected by FIR irradiation temperature of the green tea leaves.

Effect of far-infrared irradiation on the antioxidant activity of defatted sesame meal extracts.

To determine the effect of far-infrared (FIR) irradiation on the antioxidant activities of sesame meal, half of sesame seeds were FIR-irradiated and then oil was extracted from the seeds. The resulting defatted sesame meal (DSM) was extracted with methanol, and the antioxidant activities of methanolic extract were determined. FIR irradiation of sesame seeds for 30 min increased the total phenol content from 34.0 to 59.0 muM and radical scavenging activity of DSM extracts from 26.40 to 68.76%. The induction time of lipid oxidation of oil added to extracts was also retarded from 0.82 to 0.96 h. According to the gas chromatography-mass spectrometry analysis, several low molecular weight phenolic compounds, such as p-hydroxy benzoic acid, vanillic acid, p-coumaric acid, isoferulic acid, and o-coumaric acid, were frequently detected in FIR-irradiated DSM extracts as compared to unirradiated ones. These results indicated that FIR irradiation of sesame seeds increased the antioxidant activity of methanolic extracts of DSM.

Effect of heat treatment on the antioxidant activity of extracts from citrus peels.

The effect of heat treatment on the antioxidant activity of extracts from Citrus unshiu peels was evaluated. Citrus peels (CP) (5 g) were placed in Pyrex Petri dishes (8.0 cm diameter) and heat-treated at 50, 100, or 150 degrees C for 10, 20, 30, 40, 50, and 60 min in an electric muffle furnace. After heat treatment, 70% ethanol extract (EE) and water extract (WE) (0.1 g/10 mL) of CP were prepared, and total phenol contents (TPC), radical scavenging activity (RSA), and reducing power of the extracts were determined. The antioxidant activities of CP extracts increased as heating temperature increased. For example, heat treatment of CP at 150 degrees C for 60 min increased the TPC, RSA, and reducing power of EE from 71.8 to 171.0 microM, from 29.64 to 64.25%, and from 0.45 to 0.82, respectively, compared to non-heat-treated control. In the case of WE from CP heat-treated at the same conditions (150 degrees C for 60 min), the TPC, RSA, and reducing power also increased from 84.4 to 204.9 microM, from 15.81 to 58.26%, and from 0.27 to 0.96, respectively. Several low molecular weight phenolic compounds such as 2,3-diacetyl-1-phenylnaphthalene, ferulic acid, p-hydroxybenzaldoxime, 5-hydroxyvaleric acid, 2,3-diacetyl-1-phenylnaphthalene, and vanillic acid were newly formed in the CP heated at 150 degrees C for 30 min. These results indicated that the antioxidant activity of CP extracts was significantly affected by heating temperature and duration of treatment on CP and that the heating process can be used as a tool for increasing the antioxidant activity of CP.

Far-infrared radiation increases the antioxidant properties of rice hull extract in cooked turkey meat.

To determine the antioxidant effects of rice hull extract exposed to far-infrared radiation, the added extracts were compared with sesamol in cooked turkey breast. Rice hull extract showed antioxidant properties in cooked turkey breast by reducing lipid oxidation and volatile aldehydes. Far-infrared radiation increased significantly the antioxidant activities of rice hull extracts. Rice hull extract irradiated by far-infrared (FRH) had lower TBARS values and fewer volatile aldehydes (hexanal, pentanal, and propanal) than a non-irradiated extract (IRH) during the 3 days of aerobic storage. Addition of FRH at 0.2% (w/w) in turkey meat could reduce the amounts of volatile hexanal to 18-47% of the control during the storage. However, the antioxidant activities of rice hull extracts did not last as long as those of pure sesamol due to the relatively low concentration of phenolics, and the extracts had some peculiar odor. Addition of rice hull extracts also increased both a and b values of the samples due to its brown intensity.

Effect of far-infrared radiation on the antioxidant activity of rice hulls.

After far-infrared (FIR) radiation onto rice hull, a methanolic extract was prepared for the determination of antioxidant ability. After 30 min of FIR treatment, the radical scavenging activity and total phenol contents of rice hull extracts increased from 47.74 to 79.63% and from 0.12 to 0.19 mM, respectively, compared to control. Inhibition of lipid peroxidation in extracts was also increased from 41.07 to 47.96%. According to the GC-MS analysis, more phenolic compounds (p-coumaric acid, 3-vinyl-1-oxybenzene, p-hydroxybenzaldehyde, vanillin, p-hydroxybenzoic acid, and 4,7-dihydroxyvanillic acid) were detected in FIR-irradiated rice hull extract. These results indicated that FIR radiation onto rice hull could liberate and activate covalently bound phenolic compounds that have antioxidant activities.

Stabilization of retinol through incorporation into liposomes.

Chemical and photochemical processes during storage and preparation rapidly degrade retinol, the most active form of vitamin A. Therefore, the efficacy of incorporation into liposomes in order to modulate the kinetics of retinol degradation was investigated. Retinol was readily incorporated into multilamellar liposomes that were prepared from soybean phosphatidylcholine; the extent of the incorporation was 98.14 +/- 0.93% at pH 9.0 at a ratio of 0.01 : 1 (wt : wt) retinol : phospholipid. It was only marginally lower at higher retinol concentrations. The pH of the hydration buffer had a small effect. The incorporation efficiency ranged from 99.25 +/- 0.47% at pH 3 to 97.45 +/- 1.13% at pH 11. The time course of the retinol degradation in the aqueous solution in liposomes was compared to that of free retinol and free retinol with alpha-tocopherol under a variety of conditions of pH (3, 7, and 11), temperature (4, 25, 37, and 50 degrees ), and light exposure (dark, visible, and UV). The retinol that was incorporated into the liposomes degraded significantly slower than the free retinol or retinol with alpha-tocopherol at pH 7 and 11. At pH 3, where the free retinol degrades rapidly, the degradation kinetics were similar in liposomes and the presence of alpha-tocopherol. At pH 7.0 and 4 degrees in the light, for example, free aqueous retinol was completely degraded within 2 days, while only 20% of the retinol in the liposomes were degraded after 8 days. In general, the protective effect of the liposome incorporation was greater at low temperatures, at neutral and high pH, and in the dark. The results suggest that protection is greater in the solid, gel phase than in the fluid liquid crystalline phase lipids. These results indicate that the incorporation into liposomes can extend the shelf-life of retinol under a variety of conditions of temperature, pH, and ambient light conditions.