Effect of Electron-Beam Irradiation on Functional Compounds and Biological Activities in Peanut Shells.

Peanut shells, rich in antioxidants, remain underutilized due to limited research. The present study investigated the changes in the functional compound content and skin aging-related enzyme inhibitory activities of peanut shells by electron-beam treatment with different sample states and irradiation doses. In addition, phenolic compounds in the peanut shells were identified and quantified using ultra-performance liquid chromatography with ion mobility mass spectrometry-quadrupole time-of-flight and high-performance liquid chromatography with a photodiode array detector, respectively. Total phenolic compound content in solid treatment gradually increased from 110.31 to 189.03 mg gallic acid equivalent/g as the irradiation dose increased. Additionally, electron-beam irradiation significantly increased 5,7-dihydroxychrome, eriodictyol, and luteolin content in the solid treatment compared to the control. However, liquid treatment was less effective in terms of functional compound content compared to the solid treatment. The enhanced functional compound content in the solid treatment clearly augmented the antioxidant activity of the peanut shells irradiated with an electron-beam. Similarly, electron-beam irradiation substantially increased collagenase and elastase inhibitory activities in the solid treatment. Mutagenicity assay confirmed the stability of toxicity associated with the electron-beam irradiation. In conclusion, electron-beam-irradiated peanut shells could serve as an important by-product with potential applications in functional cosmetic materials.

Oat (Avena sativa) Extract against Oxidative Stress-Induced Apoptosis in Human Keratinocytes.

Oat (Avena sativa) is well known for its various health benefits. The protective effect of oat extract against oxidative stress-induced apoptosis in human keratinocytes HaCaT was determined. First, extracts of two varieties of oat, Daeyang and Choyang, were analyzed for fat-soluble antioxidants such as α-tocotrienol, γ-oryzanols, lutein and zeaxanthin using an UPLC system and for antioxidant activity using a DPPH assay. Specifically, an 80% ethanol extract of Daeyang oat (Avena sativa cv. Daeyang), which had high amounts of antioxidants and potent radical scavenging activity, was further evaluated for protective effect against oxidative stress-induced cell death, intracellular reactive oxygen species levels, the phosphorylation of DNA damage mediating genes such as H2AX, checkpoint kinase 1 and 2, and p53 and the activation of apoptotic genes such as cleaved caspase-3 and 7 and poly (ADP-ribose) polymerase in HaCaT cells. The Daeyang and Choyang oat 80% ethanol extracts had 26.9 and 24.1 mg/100 g γ-oryzanols, 7.69 and 8.38 mg/100 g α-tocotrienol, 1.25 and 0.34 mg/100 g of lutein and 1.20 and 0.17 mg/100 g of zeaxanthin, respectively. The oat 80% ethanol extract treatment (Avena sativa cv. Daeyang) had a protective effect on oxidative stress-induced cell death in HaCaT cells. In addition, the oat 80% ethanol extracts led to a significant decrease in the intracellular ROS level at a concentration of 50-200 µg/mL, the attenuation of DNA damage mediating genes and the inhibition of apoptotic caspase activities in a dose dependent manner (50-200 µg/mL). Thus, the current study indicates that an oat (Avena sativa cv. Daeyang) extract rich in antioxidants, such as polyphenols, avenanthramides, γ-oryzanols, tocotrienols and carotenoids, has a protective role against oxidative stress-induced keratinocyte injuries and that oat may a useful source for oxidative stress-associated skin damage.

Oat Extract Avenanthramide-C Reverses Hippocampal Long-Term Potentiation Decline in Tg2576 Mice.

Memory deterioration in Alzheimer's disease (AD) is thought to be underpinned by aberrant amyloid ß (Aß) accumulation, which contributes to synaptic plasticity impairment. Avenanthramide-C (Avn-C), a polyphenol compound found predominantly in oats, has a range of biological properties. Herein, we performed methanolic extraction of the Avns-rich fraction (Fr. 2) from germinated oats using column chromatography, and examined the effects of Avn-C on synaptic correlates of memory in a mouse model of AD. Avn-C was identified in Fr. 2 based on 1H-NMR analysis. Electrophysiological recordings were performed to examine the effects of Avn-C on the hippocampal long-term potentiation (LTP) in a Tg2576 mouse model of AD. Avn-C from germinated oats restored impaired LTP in Tg2576 mouse hippocampal slices. Furthermore, Avn-C-facilitated LTP was associated with changes in the protein levels of phospho-glycogen synthase kinase-3ß (p-GSK3ß-S9) and cleaved caspase 3, which are involved in Aß-induced synaptic impairment. Our findings suggest that the Avn-C extract from germinated oats may be beneficial for AD-related synaptic plasticity impairment and memory decline.

The phosphodiesterase 10 inhibitor papaverine exerts anti-inflammatory and neuroprotective effects via the PKA signaling pathway in neuroinflammation and Parkinson's disease mouse models.

BACKGROUND: Neuroinflammation plays a pivotal role in the pathogenesis of Parkinson's disease (PD). Thus, the development of agents that can control neuroinflammation has been suggested as a promising therapeutic strategy for PD. In the present study, we investigated whether the phosphodiesterase (PDE) 10 inhibitor has anti-inflammatory and neuroprotective effects in neuroinflammation and PD mouse models. METHODS: Papaverine (PAP) was utilized as a selective inhibitor of PDE10. The effects of PAP on the expression of pro-inflammatory molecules were examined in lipopolysaccharide (LPS)-stimulated BV2 microglial cells by ELISA, RT-PCR, and Western blot analysis. The effects of PAP on transcription factors were analyzed by the electrophoretic mobility shift assay, the reporter gene assay, and Western blot analysis. Microglial activation and the expression of proinflammatory molecules were measured in the LPS- or MPTP-injected mouse brains by immunohistochemistry and RT-PCR analysis. The effect of PAP on dopaminergic neuronal cell death and neurotrophic factors were determined by immunohistochemistry and Western blot analysis. To assess mouse locomotor activity, rotarod and pole tests were performed in MPTP-injected mice. RESULTS: PAP inhibited the production of nitric oxide and proinflammatory cytokines in LPS-stimulated microglia by modulating various inflammatory signals. In addition, PAP elevated intracellular cAMP levels and CREB phosphorylation. Treatment with H89, a PKA inhibitor, reversed the anti-inflammatory effects of PAP, suggesting the critical role of PKA signaling in the anti-inflammatory effects of PAP. We verified the anti-inflammatory effects of PAP in the brains of mice with LPS-induced systemic inflammation. PAP suppressed microglial activation and proinflammatory gene expression in the brains of these mice, and these effects were reversed by H89 treatment. We further examined the effects of PAP on MPTP-injected PD model mice. MPTP-induced dopaminergic neuronal cell death and impaired locomotor activity were recovered by PAP. In addition, PAP suppressed microglial activation and proinflammatory mediators in the brains of MPTP-injected mice. CONCLUSIONS: PAP has strong anti-inflammatory and neuroprotective effects and thus may be a potential candidate for treating neuroinflammatory disorders such as PD.

Phenolic compounds and antioxidant activity in sweet potato after heat treatment.

BACKGROUND: The ability of heat treatment with a soaking solvent to increase soluble phenolic compounds due to the liberation or breakdown of the cell matrix has been investigated in various plants. This study investigated the changes in phenolic compounds and antioxidant activities of 12 sweet potato cultivars after heat treatment with distilled water or prethanol A. RESULTS: The highest total polyphenol content (134.67 mg gallic acid equivalents/g extract residue) and flavonoid content (65.43 mg catechin equivalents/g extract residue) was observed in the 'Jami' (JM) cultivar after heat treatment with prethanol A. Higher polyphenol and flavonoid content was generally observed in the purple sweet potato cultivars. Salicylic acid was the major phenolic acid, followed by protocatechuic acid or chlorogenic acid in almost all untreated sweet potato cultivars. The salicylic acid, vanillic acid, gallic acid, and caffeic acid content of the sweet potatoes increased after the heat treatment, whereas the protocatechuic acid and chlorogenic acid content decreased. The highest 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis(3-ethyl benzothiazoline)-6-sulfonic acid (ABTS) radical scavenging activity levels were observed in the JM cultivar subjected to heat treatment with prethanol A (48.15 and 80.00 mg TE/g extract residue, respectively). CONCLUSION: These results suggest that heat treatment with a soaking solvent is an efficient method to enhance the antioxidant characteristics of Korean sweet potato cultivars. © 2019 Society of Chemical Industry.

Anti-inflammatory and anti-oxidant mechanisms of an MMP-8 inhibitor in lipoteichoic acid-stimulated rat primary astrocytes: involvement of NF-κB, Nrf2, and PPAR-γ signaling pathways.

BACKGROUND: Recent evidence suggests that reactive astrocytes play an important role in neuroinflammation and neurodegenerative diseases. Thus, controlling astrocyte reactivity has been suggested as a promising strategy for treating neurodegenerative diseases. In the present study, we investigated whether a matrix metalloproteinase (MMP)-8 inhibitor, M8I, could control neuroinflammation in lipoteichoic acid (LTA)-stimulated rat primary astrocytes. METHODS: The effects of M8I on the expression of inducible nitric oxide synthase, cytokines, and MMPs were examined in LTA-stimulated rat primary astrocytes by ELISA, RT-PCR, and Western blot analysis. The effects of M8I on reactive oxygen species (ROS) generation and phase II antioxidant enzyme expression were examined by the DCF-DA assay, RT-PCR, and Western blot analysis. The detailed molecular mechanisms underlying the anti-inflammatory and antioxidant effects of M8I were analyzed by the electrophoretic mobility shift assay, the reporter gene assay, Western blot, and RT-PCR analysis. RESULTS: Treatment with LTA, a major cell wall component of Gram-positive bacteria, led to astrocyte activation and induced the expression of inflammatory molecules such as iNOS, COX-2, and pro-inflammatory cytokines. In addition, LTA induced the expression of MMPs such as MMP-1, MMP-3, MMP-8, MMP-9, and MMP-13 in rat primary astrocytes. Based on previous reports showing that MMP-8 plays a role as a proinflammatory mediator in microglia, we investigated whether MMP-8 is also involved in inflammatory reactions of reactive astrocytes. We found that treatment of astrocytes with M8I significantly inhibited LTA-induced expression of iNOS, TNF-α, IL-1ß, IL-6, and TLR-2. In addition, M8I inhibited LTA-induced NF-κB, MAP kinase, and Akt activities, while it increased the anti-inflammatory PPAR-γ activities. Moreover, M8I showed antioxidant effects by suppressing ROS production in LTA- or H2O2-stimulated astrocytes. Interestingly, M8I increased the expression of phase II antioxidant enzymes such as hemeoxygenase-1, NQO1, catalase, and MnSOD by modulating the Nrf2/ARE signaling pathway. CONCLUSIONS: The data collectively suggest the therapeutic potential of an MMP-8 inhibitor in neuroinflammatory disorders that are associated with astrocyte reactivity.

Enhanced Antioxidant Activity of Bioactives in Colored Grains by Nano-Carriers in Human Lens Epithelial Cells.

The use of phytochemicals for preventing chronic diseases associated with oxidative stress such as cataracts is hindered by their low bioavailability. The effects of nano-carriers on the antioxidant activities of extracts of black rice with giant embryo (BRGEx) and soybeans (SBx) have been determined in human lens epithelial B3 cells. Scanning (SEM) and transmission electron microscopy (TEM) demonstrated that rGO (reduced graphene oxide) has a flat surface unlike GO (graphene oxide), which has a distinctive wrinkled structure with defects. UPLC analysis revealed 41.9 µg/100 g of γ-oryzanols in water extract of BRGE, and 111.8 µg /100 g of lutein, 757.7 µg/100 g of γ-tocotrienol, 4071.4 µg/100 g of γ-tocopherol in 40% ethanol extract of soybeans, respectively. Even though a low concentration of BRGEx alone did not show any antioxidant activity in B3 cells, co-treatment of BRGEx with rGO together substantially reduced hydrogen peroxide and methylglyoxal-induced DNA damage, as determined by phosphorylated γH2AX. In addition, SBx with rGO also attenuated DNA damage. Furthermore, intracellular reactive oxygen species were significantly decreased by combining extracts of these colored grains with rGO. These results suggest a potential application of nanocarriers for enhancing the bioavailability of phytochemicals.

A correlation between tocopherol content and antioxidant activity in seeds and germinating seeds of soybean cultivars.

BACKGROUND: Tocopherols are crucial lipid-soluble antioxidants and essential nutrients. There is increasing interest in the biofortification of crops with vitamin E for reducing micronutrient malnutrition. However, relatively little is known about the development of soybean cultivars with high levels of tocopherol through combined breeding. RESULT: Tocopherol contents of seeds and germinating seeds of 28 Korean soybean cultivars were analyzed and evaluated for health-promoting activities. Total tocopherol concentrations ranged from 203.9 to 503.1 µg g⁻¹ in seeds and from 20.1 to 230.1 µg g⁻¹ in germinating seeds. The traditional landraces of HaNagari (HN, 503.1 µg g⁻¹), Orialtae (OL, 486.6 µg g⁻¹), SuMoktae (SM, 476.5 µg g⁻¹) and SoRitae (SR, 475.5 µg g⁻¹) showed high levels of tocopherol content. The contents of the four isomers of tocopherol in seeds and germinating seeds were correlated with lipid peroxidation. The γ- and δ-tocopherol contents in seeds were related to 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity (0.434; P < 0.01 and 0.373; P < 0.05). CONCLUSION: Total tocopherol content was higher in soybean landraces as compared with modern cultivars developed by cross-breeding. These results suggest that soybean breeding is necessary to increase tocopherol levels.

Comparative study on the effects of grain blending on functional compound content and in vitro biological activity.

In this study, changes in bioactive compound contents and the in vitro biological activity of mixed grains, including oats, sorghum, finger millet, adzuki bean, and proso millet, with eight different blending ratios were investigated. The total phenolic compounds and flavonoid contents ranged from 14.43-16.53 mg gallic acid equivalent/g extract and 1.22-5.37 mg catechin equivalent/g extract, respectively, depending on the blending ratio. The DI-8 blend (30% oats, 30% sorghum, 15% finger millet, 15% adzuki bean, and 10% proso millet) exhibited relatively higher antioxidant and anti-diabetic effects than other blending samples. The levels of twelve amino acids and eight organic acids in the grain mixes were measured. Among the twenty metabolites, malonic acid, asparagine, oxalic acid, tartaric acid, and proline were identified as key metabolites across the blending samples. Moreover, the levels of lactic acid, oxalic acid, and malonic acid, which are positively correlated with α-glucosidase inhibition activity, were considerably higher in the DI-blending samples. The results of this study suggest that the DI-8 blend could be used as a functional ingredient as it has several bioactive compounds and biological activities, including anti-diabetic activity.

Anti-inflammatory effect of ginsenoside Rg5 in lipopolysaccharide-stimulated BV2 microglial cells.

Microglia are resident immune cells in the central nervous system. They play a role in normal brain development and neuronal recovery. However, overactivation of microglia causes neuronal death, which is associated with neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease. Therefore, controlling microglial activation has been suggested as an important target for treatment of neurodegenerative diseases. In the present study, we investigated the anti-inflammatory effect of ginsenoside Rg5 in lipopolysaccharide (LPS)-stimulated BV2 microglial cells and rat primary microglia. The data showed that Rg5 suppressed LPS-induced nitric oxide (NO) production and proinflammatory TNF-α secretion. In addition, Rg5 inhibited the mRNA expressions of iNOS, TNF-α, IL-1b, COX-2 and MMP-9 induced by LPS. Further mechanistic studies revealed that Rg5 inhibited the phophorylations of PI3K/Akt and MAPKs and the DNA binding activities of NF-kB and AP-1, which are upstream molecules controlling inflammatory reactions. Moreover, Rg5 suppressed ROS production with upregulation of hemeoxygenase-1 (HO-1) expression in LPS-stimulated BV2 cells. Overall, microglial inactivation by ginsenoside Rg5 may provide a therapeutic potential for various neuroinflammatory disorders.

Confirmation of the Applicability of Skeletochronology and Estimating the Age Structure of Kaloula borealis (Microhylidae: Anura) at Lake Sihwa, South Korea.

Despite having some limitations, the use of skeletochronology-age determination by counting lines of arrested growth (LAGs)-in amphibians is increasing. The main limitation of using skeletochronology is identifying the innermost visible line (IVL) and counting the exact number of LAGs. Thus, we tested its applicability to Kaloula borealis, a class II endangered amphibian in South Korea. We reared juveniles in the lab to investigate the process of bone formation. This confirmed the development of one LAG each year. Hence, our study validates skeletochronology for the age determination of this species and recommends it for others that show similar growth patterns. Furthermore, the comparison of threshold diameters with the IVL of wild individuals confirmed no LAG1 resorption. The average age of males and females in this population was 2.75 ± 1.05 and 3.64 ± 3 years, respectively. We estimated sexual maturity at 2 years with rapid growth up to that stage in both sexes. We found a female-dominated sexual size dimorphism. This study offers accurate information on the life history traits and age structure of K. borealis that may help to evaluate population dynamics in other areas, identify vulnerable life stages and sites, assess the causes of population decline, and set conservation priorities.

Effect of Atmospheric-Pressure Plasma on Functional Compounds and Physiological Activities in Peanut Shells.

Peanut (Arachis hypogaea L.) shell, an abundant by-product of peanut production, contains a complex combination of organic compounds, including flavonoids. Changes in the total phenolic content, flavonoid content, antioxidant capacities, and skin aging-related enzyme (tyrosinase, elastase, and collagenase)-inhibitory activities of peanut shell were investigated after treatment in pressure swing reactors under controlled gas conditions using surface dielectric barrier discharge with different plasma (NOx and O3) and temperature (25 and 150 °C) treatments. Plasma treatment under ozone-rich conditions at 150 °C significantly affected the total phenolic (270.70 mg gallic acid equivalent (GAE)/g) and flavonoid (120.02 mg catechin equivalent (CE)/g) contents of peanut shell compared with the control (253.94 and 117.74 mg CE/g, respectively) (p < 0.05). In addition, with the same treatment, an increase in functional compound content clearly enhanced the antioxidant activities of components in peanut shell extracts. However, the NOx-rich treatment was significantly less effective than the O3 treatment (p < 0.05) in terms of the total phenolic content, flavonoid content, and antioxidant activities. Similarly, peanut shells treated in the reactor under O3-rich plasma conditions at 150 ℃ had higher tyrosinase, elastase, and collagenase inhibition rates (55.72%, 85.69%, and 86.43%, respectively) compared to the control (35.81%, 80.78%, and 83.53%, respectively). Our findings revealed that a reactor operated with O3-rich plasma-activated gas at 150 °C was better-suited for producing functional industrial materials from the by-products of peanuts.

Antioxidant and anti-inflammatory effects of Peanut (Arachishypogaea L.) skin extracts of various cultivars in oxidative-damaged HepG2 cells and LPS-induced raw 264.7 macrophages.

This study was performed to investigate the distribution of phenolic compounds in the peanut skins of various cultivars, as well as their antioxidant and anti-inflammatory effect (Arachishypogaea L. cv. K-Ol, cv. Sinpalkwang, cv. Daan, cv. Heuksaeng) and extraction solvent. The major components of red peanut cultivars (K-Ol, Sinpalkwang, and Daan) were identified as proanthocyanidin, catechin, gallic acid, coumaric acid, and hesperidine, whereas the major components of black peanut cultivar (Heuksaeng) were identified as anthocyanin, ferulic acid, and quercetin. The DPPH and ABTS radical scavenging activities, and FRAP values were the highest in Daan followed by Sinpalkwng, K-Ol, and Heuksang. Furthermore, the skin extracts of red peanuts effectively improved cell viability, reactive oxygen species generation, MDA concentration, and antioxidant enzyme activity (GR, GPx, CAT, and superoxide dismutase) in oxidative stress-induced HepG2 cells, and reduced the expression of pro-inflammatory factors (NO, TNF-α, IL-6, and IL-1ß) in LPS-stimulated RAW 264.7 macrophages. These results suggest that red peanut skin extracts could effectively mediate physiological activity and provide valuable information for the use of peanut byproducts as functional food materials.

Physicochemical Characteristics of Starch in Sweet Potato Cultivars Grown in Korea.

The objective of this study was to investigate the structural and physicochemical properties of starch from seven sweet potato cultivars (Shinyulmi, Sinjami, Hogammi, Jeonmi, Jinyulmi, Juhwangmi, and Pungwonmi). Jeonmi and Jinyulmi had amylose contents of 40.04% and 37.39%, respectively, whereas Juhwangmi and Pungwonmihad amylose contents of 30.95% and 32.37%, respectively. As a result of amylopectin polymerization, the seven cultivars were found to have high (>48%) contents of the degree of polymerization (DP) 13∼24 fraction, whereas the DP≥37 fraction content was <3.45%. The level of resistant starch was highest in Jeonmi (>30%) and lowest in Pungwonmi (<5%). The in vitro digestibility of Pungwonmi was greater than that of the other cultivars. Starch X-ray patterns did not differ among the cultivars. The results of this study provide useful information for the food industry regarding the application of sweet potato starches.

Avenanthramide-C Restores Impaired Plasticity and Cognition in Alzheimer's Disease Model Mice.

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive decline and dementia with no effective treatment. Here, we investigated a novel compound from oats named avenanthramide-C (Avn-C), on AD-related memory impairment and behavioral deficits in transgenic mouse models. Acute hippocampal slices of wild-type or AD transgenic mice were treated with Avn-C in the presence or absence of oligomeric Aß42. LTP analyses and immunoblotting were performed to assess the effect of Avn-C on Aß-induced memory impairment. To further investigate the effect of Avn-C on impaired memory and Aß pathology, two different AD transgenic mice (Tg2576 and 5XFAD) models were orally treated with either Avn-C or vehicle for 2 weeks. They were then assessed for the effect of the treatment on neuropathologies and behavioral impairments. Avn-C reversed impaired LTP in both ex vivo- and in vivo-treated AD mice hippocampus. Oral administration (6 mg/kg per day) for 2 weeks in AD mice leads to improved recognition and spatial memory, reduced caspase-3 cleavage, reversed neuroinflammation, and to accelerated glycogen synthase kinase-3ß (pS9GSK-3ß) and interleukin (IL-10) levels. Avn-C exerts its beneficial effects by binding to α1A adrenergic receptors to stimulate adenosine monophosphate-activated kinase (AMPK). All of the beneficial effects of Avn-C on LTP retrieval could be blocked by prazosin hydrochloride, a specific inhibitor of α1A adrenergic receptors. Our findings provide evidence, for the first time, that oats' Avn-C reverses the AD-related memory and behavioral impairments, and establish it as a potential candidate for Alzheimer's disease drug development.

Intracellular Reactive Oxygen Species (ROS) Removal and Cytoprotection Effects of Sweet Potatoes of Various Flesh Colors and Their Polyphenols, Including Anthocyanin.

The flesh color of sweet potatoes varies based on the antioxidant pigments in the cultivar. In this study, the antioxidant characteristics of various flesh color sweet potato cultivars (Jinyulmi, Juhwangmi, Pungwonmi, and Sinjami) were investigated. The polyphenol contents were highest in the purple-fleshed cultivar, Sinjami (39, 68, and 71 µg gallic acid equivalent/g in distilled water, fermented ethanol, and ethanol extracts, respectively). The Sinjami cultivar contained 29 mg/100 g of anthocyanin, which is the major component resulting in increased concentrations of polyphenols. Using 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid), 2,2-diphenyl-1-picrylhydrazyl, and ferric reducing ability of plasma assays, Sinjami showed greater antioxidant activity than the other cultivars. Additionally, the Sinjami extracts could recover cellular reactive oxygen species levels in tert-butyl hydroperoxide-stimulated HepG2 cells to a normal level. In conclusion, anthocyanin-enriched Sinjami has strong antioxidant activities and could improve health by suppressing oxidative damage.

Oat germination and ultrafiltration process improves the polyphenol and avenanthramide contents with protective effect in oxidative-damaged HepG2 cells.

Oat is the nutritious crop containing various compounds with antioxidant properties, such as polyphenols. In this study, we investigated the effect of germination and ultrafiltration process on polyphenol and avenanthramide contents in oat as well as their cytoprotective effect. Germination of oat for 48 hr significantly increased avenanthramide (5.5 to 11.3 mg/g) and polyphenol (115 to 155 mg GAE/g) contents. The compounds were more concentrated after ultrafiltration using 10 kDa membranes (polyphenol, 206 GAE/g; avenanthramide, 18 mg/g). In addition, oat extracts significantly reduced the cellular ROS level against tert-butyl hydroperoxide (t-BHP) stimulation in HepG2 cells. In the mechanistic study, oat extracts induced Nrf2 translocation to the nucleus by inhibition of Keap1 expression, resulting into upregulation of γ-GCS and NQO1. In conclusion, oat germination and ultrafiltration processes increased the polyphenol content, including that of avenanthramide. These extracts protected cells from t-BHP by radical scavenging activities and induced Nrf2 pathway activation. PRACTICAL APPLICATIONS: This study presents the method for avenanthramide-concentrated extract which is unique bioactive compounds in oat. In addition, antioxidant activity and their mechanisms of the avenanthramide-enriched extracts were evaluated. The polyphenol compounds including avenanthramide were found to increase after germination and ultrafiltration, thereby improving the radical scavenging ability. These results can be utilized as data for the development of health-promoting materials using oats.

Black soybeans protect human keratinocytes from oxidative stress-induced cell death.

Black soybeans are functional foods containing a variety of bioactives such as isoflavones, carotenoids, tocopherols, phenolic acid as well as anthocyanins. Here, we examined whether Cheongja#3 black soybean extract has a protective effect on oxidative stress-induced cell death in human keratinocytes HaCaT. First, we identified fat-soluble bioactives in three varieties of soybean extracts (Saedanbaek, Daechan, and Cheongja#3). In particular, black soybean Cheongja#3 had high amounts of lutein than other varieties. We demonstrated that Cheongja#3 extract reduced intracellular reactive oxygen species levels in HaCaT cells. Furthermore, Cheongja#3 protected cells from hydrogen peroxide (H2O2)-induced oxidative stress and triggered cell death determined by cell viabilities and apoptotic caspase activities. Next, we identified the underlying mechanism is due to increased Nrf2 antioxidant system by Cheongja#3, thus increasing the expression of heme oxygenases (HO)-1. These results indicated that Cheongja#3 soybean extract has protective role against oxidative stress by upregulating the Nrf-2 antioxidant system in human keratinocyte HaCaT cells.

Assessment of microbial safety and quality changes of brown and white cooked rice treated with atmospheric pressure plasma.

The microbial and physicochemical properties of brown and white cooked rice treated by atmospheric pressure plasma (APP). APP was produced (250 W, 15 kHz, ambient air) and applied to brown and white cooked rice for 5, 10, and 20 min. The 20-min plasma treatment reduced in bacterial counts by 2.01 log CFU/g when cooked rice were inoculated with Bacillus cereus or Escherichia coli O157:H7. The pH of the brown cooked rice was decreased by the 5-min plasma. The hardness values of APP-treated brown and white cooked rice were lower than untreated samples. The reducing sugar contents of brown and white cooked rice were significantly higher than those in untreated samples. Lipid oxidation of APP-treated brown and white cooked rice were higher compared to untreated samples. These results indicate that APP improves microbial quality, although further studies should be conducted to change the physicochemical qualities of brown and white cooked rice induced by APP.

Suppression of Lipopolysaccharide-Induced Neuroinflammation by Morin via MAPK, PI3K/Akt, and PKA/HO-1 Signaling Pathway Modulation.

Morin is a flavonoid isolated from certain fruits and Chinese herbs and is known to possess various medicinal properties. In this study, we investigated the anti-inflammatory effects of morin on lipopolysaccharide (LPS)-induced microglial activation, both in vitro and in vivo. We found that morin inhibited inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines in LPS-stimulated BV2 microglial cells. Furthermore, morin suppressed the microglial activation and cytokine expression in the brains of LPS-stimulated mice. Subsequent mechanistic studies revealed that morin inhibited the action of LPS-activated mitogen-activated protein kinases (MAPKs), protein kinase B (Akt) phosphorylation, nuclear factor-κB (NF-κB), and activating protein-1 (AP-1). Further, the phosphorylation and DNA binding activity of cAMP responsive element binding protein (CREB) was enhanced by morin. Moreover, morin suppressed the LPS-induced expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits, while it increased heme oxygenase-1 (HO-1) expression and nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Therefore, our data suggest that morin exerts anti-inflammatory effects in LPS-stimulated microglia by downregulating MAPK and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways while upregulating protein kinase A (PKA)/CREB and Nrf2/HO-1 signaling pathways.