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  • 1.

    【2hr】Comparative Examination of Antioxidant Capacity and Fingerprinting of Unfractionated Extracts from Different Plant Parts of Quinoa (Chenopodium quinoa) Grown under Greenhouse Conditions

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    机译 温室条件下藜麦（Chenopodium quinoa）不同植物部位未分级提取物的抗氧化能力和指纹图谱的比较检查
    摘要：Integrated surveys of metabolic profiles and antioxidant capacity from Chenopodium quinoa have been limited and have particularly focused on an examination of seeds and leaves. According to this, the main aim of the present study was to address an evaluation of the antioxidant activity of crude ethanolic extracts from different plant parts (leaves, stems, roots, flowers, and seeds) harvested at different times during growth and processed by two distinct drying methods: Air-drying and freeze-drying. In order to characterize the resulting extracts, the total content of phenolics (TPC) and flavonoids (TFC) was then measured through the Folin–Ciocalteu method, while antioxidant capacity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH•) free radical scavenging and ferric-reducing antioxidant power (FRAP) methods. Parallel to this evaluation, extracts were profiled by LC-DAD-ESI-MS. Data analysis was supported by statistics. Most of the extracts obtained from freeze-dried samples showed higher TPC values ranging from 6.02 to 43.47 milligram of gallic acid equivalents per gram of plant material and a TFC between 1.30 and 12.26 milligram of quercetin equivalents per gram of plant material. After statistical analysis, a low correlation between TPC and TFC values was observed regarding antioxidant capacity from DPPH and FRAP measurements of both drying methods. A multivariate analysis showed that antioxidant components and antioxidant capacity in C. quinoa changed during growth and between plant parts and drying methods. These changes need to be taken into consideration when comparing the production/accumulation of beneficial bioactive compounds in this pseudocereal.
  • 2.

    【2hr】Fucoxanthin—An Antibacterial Carotenoid

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    机译 岩藻黄质—一种抗菌类胡萝卜素
    摘要：Fucoxanthin is a carotenoid produced by brown algae and diatoms. This compound has several biological properties such as antioxidant, anti-obesity, anti-diabetic, anticancer, and antimicrobial activities. Unfortunately, until now the latter effect has been poorly confirmed. The aim of this study was an evaluation of fucoxanthin activity against 20 bacterial species. Antimicrobial effect of fucoxanthin was determined by using the agar disc-diffusion and micro-dilution methods. The studied carotenoid acted against 13 bacteria growing in aerobic conditions. It was observed to have a significantly stronger impact on Gram-positive than Gram-negative bacteria. Mean zones of growth inhibition (ZOIs) for Gram-positive bacteria ranged between 9.0 and 12.2 mm, while for Gram-negative were from 7.2 to 10.2 mm. According to the agar disc-diffusion method, the highest activity of fucoxanthin was exhibited against Streptococcus agalactiae (mean ZOI 12.2 mm), Staphylococcus epidermidis (mean ZOI 11.2 mm), and Staphylococcus aureus (mean ZOI 11.0 mm), and in the microdilution test towards Streptococcus agalactiae with the minimal inhibitory concentration (MIC) of 62.5 µg/mL. On the other hand, fucoxanthin was not active against strict anaerobic bacteria.
  • 3.

    【2hr】Phlorotannins with Potential Anti-Tyrosinase and Antioxidant Activity Isolated from the Marine Seaweed Ecklonia stolonifera

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    机译 从海藻Ecklonia stolonifera中分离出具有潜在抗酪氨酸酶和抗氧化活性的环戊宁
    摘要：Compounds were isolated from Ecklonia stolonifera Okamura, a marine brown alga widely consumed as food. Among the isolated compounds, 974-A was demonstrated for the first time to be a potent competitive inhibitor of mushroom tyrosinase activity towards l-tyrosine and l-DOPA (IC50 values = 1.57 ± 0.08 and 3.56 ± 0.22 µM, respectively). Molecular docking simulations clarified that the hydroxyl residues of the isolated compounds formed hydrogen bonds with residues at the catalytic and allosteric sites of tyrosinase, while other residues participated in hydrophobic interactions. Moreover, 974-A, phlorofucofuroeckol-A and eckol reduced the cellular melanin content and tyrosinase activity, and downregulated the expression of melanogenesis enzymes including tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 in B16F10 melanoma cells. These compounds also effectively scavenged radicals at the cellular level. Thus, our results revealed that compounds isolated from E. stolonifera are potent tyrosinase inhibitors with potential applications in the cosmetic industry for treatment of hyperpigmentation and for the anti-browning effect in the agricultural field.
  • 4.

    【2hr】The Health-Benefits and Phytochemical Profile of Salvia apiana and Salvia farinacea var. Victoria Blue Decoctions

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    机译 Salvia apiana和Salvia farinacea var的健康益处和植物化学特征。维多利亚蓝十进制
    摘要：Salvia apiana and Salvia farinacea var. Victoria Blue decoctions were screened for diverse bioactivities, including the ability to counteract oxidative and inflammatory events, as well as to act as cytotoxic and antimicrobial agents. Both extracts showed good activities and that of S. apiana origin was particularly effective regarding the ability to prevent lipid peroxidation and to prevent nitric oxide (NO●) production in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cell line (EC50 = 50 μg/mL). Moreover, it displayed high cytotoxic capacity against hepatocellular carcinoma HepG2, cervical carcinoma HeLa, and breast carcinoma cells MCF-7, but comparatively low effects in porcine liver primary cells, which highlights its selectivity (GI50 = 41–60 μg/mL vs. 362 μg/mL, respectively). Further, it exhibited inhibitory and lethal potential against a panel of Gram-positive and Gram-negative bacteria. It is possible that the bioactive properties of the two Salvia extracts are associated to their phenolic components and, in the particular case of S. apiana, to its richness in phenolic terpenes, namely in rosmanol, hydroxycarnosic acid and a derivative of sageone, which were found in the extract.
  • 5.

    【2hr】Optimization of Ultrasound-Assisted Extraction of Antioxidant Polyphenols from the Seed Coats of Red Sword Bean (Canavalia gladiate (Jacq.) DC.)

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    机译 超声波辅助提取红剑豆种皮中抗氧化多酚的工艺优化（Canavalia gladiate（Jacq。）DC。）
    摘要：The seed coat of red sword bean (Canavalia gladiata (Jacq.) DC.) is rich in antioxidant polyphenols. It is often discarded as a byproduct with the consumption of red sword bean, since it is very thick and not consumed by people. The aim of this study was to develop an ultrasound-assisted extraction method to extract natural antioxidants from the seed coats. The extraction process was optimized by using response surface methodology. After the single-factor experiments, three key factors, including ethanol concentration, liquid/solid ratio, and extraction time, were selected and their interactions were studied using a central composite design. The optimal extraction condition was 60.2% hydroethanol, a liquid/solid ratio of 29.3 mL/g, an extraction time of 18.4 min, an extraction temperature of 50 °C, and ultrasound power of 400 W. Under the optimal conditions, antioxidant activity of the extract was 755.98 ± 10.23 μmol Trolox/g dry weight (DW), much higher than that from maceration (558.77 ± 14.42 μmol Trolox/g DW) or Soxhlet extraction (479.81 ± 12.75 μmol Trolox/g DW). In addition, the main antioxidant compounds in the extract were identified and quantified by high-performance liquid chromatography–diode array detection–tandem mass spectrometry (HPLC–DAD–MS/MS). The concentrations of digalloyl hexoside, methyl gallate, gallic acid, trigalloyl hexoside, and digallic acid were 15.30 ± 0.98, 8.85 ± 0.51, 8.76 ± 0.36, 4.27 ± 0.21, and 2.89 ± 0.13 mg/g DW. This study provides an efficient and green extraction method for the extraction of natural antioxidants from the bean coat of red sword bean. The extract of antioxidants might be added into functional foods or nutraceuticals with potential beneficial functions.
  • 6.

    【2hr】Analysis of Olive (Olea Europaea L.) Genetic Resources in Relation to the Content of Vitamin E in Virgin Olive Oil

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    机译 初榨橄榄油中橄榄（Olea Europaea L.）遗传资源与维生素E含量的关系分析
    摘要：Virgin olive oil (VOO) is the main source of lipids in the Mediterranean diet and one of the main contributors to its proven protection against diseases associated with chronic inflammation states. This oil is rich in antioxidant compounds such as tocopherols, which together constitute the vitamin E stock of the oil. The purpose of the present work was to conduct a study on the diversity of the contents of vitamin E in the olive species (Olea europaea L.), and to know how the season climatic conditions and the degree of fruit ripening stage influences the final content of this vitamin in VOO. Data showed that the content of vitamin E in VOO is highly dependent on the olive cultivar, displaying a wide variability (89–1410 mg tocopherol/kg oil) in the olive species, and that is also dependent, to a lesser extent, on the crop year climate and the stage of fruit ripening. In addition, the suitability of cultivar crosses for breeding programs to obtain new cultivars with improved vitamin E content in VOO has been assessed. Our findings demonstrated that a single cross of olive cultivars may provide sufficient variability to be used in the selection of new cultivars.
  • 7.

    【2hr】Effect of Sterigmatocystin or Aflatoxin Contaminated Feed on Lipid Peroxidation and Glutathione Redox System and Expression of Glutathione Redox System Regulatory Genes in Broiler Chicken

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    机译 曲霉毒素或黄曲霉毒素污染饲料对肉鸡脂质过氧化和谷胱甘肽氧化还原系统及谷胱甘肽氧化还原系统调控基因表达的影响
    摘要：Authors studied the effect of sterigmatocystin from infected corn (STC), purified sterigmatocystin (PSTC), and aflatoxin B1 from infected corn (AFB1) on lipid peroxidation and glutathione redox parameters, including the expression of their encoding genes in a sub-chronic (14 days) trial. A total of 144 three-week-old cockerels was divided into four experimental groups (n = 36 in each). Control feed was contaminated with STC or PSTC (1590 µg STC/kg or 1570.5 µg STC/kg feed), or with AFB1 (149.1 µg AFB1/kg feed). Six birds from each group were sampled at day 1, 2, 3, 7 and 14 of mycotoxin exposure. As parameters of lipid peroxidation, conjugated dienes (CD) and trienes (CT) were measured in the liver, while malondialdehyde (MDA) concentration was determined in blood plasma, red blood cell hemolysate and liver. Reduced glutathione (GSH) concentration and glutathione peroxidase (GPx) activity were determined in the same samples, and expression of glutathione peroxidase 4 (GPX4), glutathione synthetase (GSS) and glutathione reductase (GSR) genes was measured by RT-PCR in the liver. STC, PSTC or AFB1 caused a slight, but not significant, increase in CD and CT levels; however, in the case of MDA, no increase was found in the liver. Glutathione redox system was activated in the liver by AFB1, but less markedly by STC/PSTC. PSTC and AFB1 resulted in a higher expression of GPX4, while GSS expression was down-regulated by AFB1 on day 1, but up-regulated by STC on day 2 and by both mycotoxins on day 7. However, on day 14, GSS expression was down-regulated by PSTC. Expression of GSR was low on day 1 in AFB1 and PSTC groups, but later it was up-regulated by AFB1. The observed changes regarding gene expression strengthen the hypothesis that the mild oxidative stress, caused by the applied STC doses, activates the glutathione redox system of broiler chickens.
  • 8.

    【2hr】Antioxidant Activity of Thyme Waste Extract in O/W Emulsions

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    机译 百里香废弃物提取物在O / W乳液中的抗氧化活性
    摘要：Thymus vulgaris (thyme) is an aromatic plant and its essential oil has been applied as antimicrobial and antioxidant due to the presence of phenolic compounds. However, after steam distillation, the deodorized plant material is rejected, despite the possible presence of bioactive compounds. Ethanolic thyme waste extract revealed the presence of benzoic acid, 4-hydroxybenzoic acid, ferulic acid, caffeic acid, and sinapic acid. This waste thyme extract had the capacity for preventing the formation of primary and secondary lipid oxidation products in emulsions O/W (oil in water), constituted by diverse proportions of wheat and almond oils, without interfering with the viscosity parameters, for 10 weeks, at 37 °C. The increasing proportion of almond oil (≥50%) in the emulsion increases its resistance to oxidation, which is improved with the presence of an optimal concentration of tested thyme waste extract (0.02% and 0.04%). The waste thyme extract can, therefore, be used as an antioxidant either in food or pharmaceutical emulsions O/W, replacing the synthetic antioxidants.
  • 9.

    【2hr】Nutritional Composition, Total Phenolic Content, Antioxidant and α-Amylase Inhibitory Activities of Different Fractions of Selected Wild Edible Plants

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    机译 野生食用植物不同部位的营养成分，总酚含量，抗氧化和α-淀粉酶抑制活性
    摘要：Wild plants are considered the richest source of essential nutrients and other beneficial phytochemicals. Hence, the objective of this study was to evaluate the nutritional composition, antioxidant- and α-amylase inhibition activities of leaves and roots of selected Bangladeshi wild plants. These wild plants were found to have high fiber (13.78–22.26 g/100 g), protein (7.08–21.56 g/100 g) and ash (8.21–21.43 g/100 g) contents. The total phenolic and total flavonoid contents were significantly higher in the leaves than the roots. Additionally, antioxidant activity was evaluated using ferric-reducing antioxidant power, 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH) and trolox equivalent antioxidant capacity assays and was strongly correlated with phenolic compounds. The leaf extracts of the selected plants also exhibited potent α-amylase inhibition (~71%) and were significantly higher than their root counterparts. Thus, the study findings concluded that the investigated plants were good sources of fiber, protein, mineral, natural antioxidant compounds and α-amylase inhibitors, and their increased intake could provide health benefits. The principal component analysis (PCA) of analyzed variables divided the samples into three clear groups, and the first two principal components accounted for 86.05% of the total data set variance.
  • 10.

    【2hr】Sex-dependent Differences in the Bioenergetics of Liver and Muscle Mitochondria from Mice Containing a Deletion for glutaredoxin-2

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    机译 性别和动物的肝脏和线粒体的生物能学差异从谷胱甘肽2的删除。
    摘要：Our group recently published a study demonstrating that deleting the gene encoding the matrix thiol oxidoreductase, glutaredoxin-2 (GRX2), alters the bioenergetics of mitochondria isolated from male C57BL/6N mice. Here, we conducted a similar study, examining H2O2 production and respiration in mitochondria isolated from female mice heterozygous (GRX2+/−) or homozygous (GRX2−/−) for glutaredoxin-2. First, we observed that deleting the Grx2 gene does not alter the rate of H2O2 production in liver and muscle mitochondria oxidizing pyruvate, α-ketoglutarate, or succinate. Examination of the rates of H2O2 release from liver mitochondria isolated from male and female mice revealed that (1) sex has an impact on the rate of ROS production by liver and muscle mitochondria and (2) loss of GRX2 only altered ROS release in mitochondria collected from male mice. Assessment of the bioenergetics of these mitochondria revealed that loss of GRX2 increased proton leak-dependent and phosphorylating respiration in liver mitochondria isolated from female mice but did not alter rates of respiration in liver mitochondria from male mice. Furthermore, we found that deleting the Grx2 gene did not alter rates of respiration in muscle mitochondria collected from female mice. This contrasts with male mice where loss of GRX2 substantially augmented proton leaks and ADP-stimulated respiration. Our findings indicate that some fundamental sexual dimorphisms exist between GRX2-deficient male and female rodents.
  • 11.

    【2hr】Antioxidant Activities and Total Phenolic Content of Malaysian Herbs as Components of Active Packaging Film in Beef Patties

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    机译 作为牛肉饼活性包装膜成分的马来西亚草药的抗氧化活性和总酚含量
    摘要：Active packaging containing natural extracts is a promising innovation to prolong the shelf life of perishable food. The objective of this work was to develop a bioactive edible film from semi-refined carrageenan (SRC) and glycerol (G) as plasticizer incorporated with natural extract. Five Malaysian herbs were evaluated to determine their total phenolic content (TPC) and antioxidant activities. The Persicaria minor (PM) extract demonstrated the highest TPC (1.629 mg GAE/L sample) and radical scavenging activity evaluated by the radicals 2,2’-azinobis [3-ethylbenzothiazoline-6-sulfonic acid] (27.166 mg TE/L sample), 2,2-diphenyl-1-picrylhydrazyl (719.89 mg eq. Trolox/L sample) and α,α′-Azodiisobutyramidine dihydrochloride (5.81 mg TE/L sample). Thus, PM extract was selected for active packaging film at concentrations of 0.4, 1.0 and 2.0% and compared with 0.4% Butylatedhydroxianisole in 2% SRC and 0.9% G film formulation. The meat patties were wrapped in the films and stored under refrigeration (4 ± 2 °C) for 14 days. The film with 2% PM exhibited significantly lower lipid deterioration analysed by the thiobarbituric acid reactive substance assay (p < 0.05) and small changes in % metmyoglobin value which indicated the minimum development of brown colour (p < 0.05). Hence, this film can be used as a packaging material to improve meat quality characteristics.
  • 12.

    【2hr】Changes in the Antioxidant Properties of Extra Virgin Olive Oil after Cooking Typical Mediterranean Vegetables

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    机译 烹调典型地中海蔬菜后特级初榨橄榄油抗氧化性能的变化
    摘要：Extra virgin olive oil (EVOO), water, and a water/oil mixture (W/O) were used for frying, boiling and sautéeing Mediterranean vegetables (potato, pumpkin, tomato and eggplant). Differences in antioxidant capacity (AC) (2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric iron (FRAP), 2,2-azinobis-(3-ethylbensothiazoline)-6-sulphonic acid (ABTS)), total phenolic content (TPC) and individual phenols (high-performance liquid chromatography (HPLC)) in unused and used EVOO and water were determined. The water used to boil tomatoes showed the highest TPC value, whilst the lowest was found in the EVOO from the W/O used for boiling potatoes. After processing, the concentrations of phenols exclusive to EVOO diminished to different extents. There was a greater transfer of phenols from the vegetable to the oil when eggplant, tomato and pumpkin were cooked. W/O boiling enriched the water for most of the phenols analysed, such as chlorogenic acid and phenols exclusive to EVOO. The values of AC decreased or were maintained when fresh oil was used to cook the vegetables (raw > frying > sautéing > boiling). The water fraction was enriched in 6-hydroxy-2,5,7,8–tetramethyl-chroman-2-carboxylic acid (Trolox) equivalents following boiling, though to a greater extent when EVOO was added. Phenolic content and AC of EVOO decreased after cooking Mediterranean diet vegetables. Further, water was enriched after the boiling processes, particularly when oil was included.
  • 13.

    【2hr】Optimization of Ultrasound-Assisted Extraction of Polyphenols from Myrtus communis L. Pericarp

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    机译 超声波辅助提取桃金娘多酚的工艺优化
    摘要：Response surface methodology (RSM) was used to optimize the extraction of phenolics from pericap of Myrtus communis using ultrasound-assisted extraction (UAE). The results were compared with those obtained by microwave-assisted extraction (MAE) and conventional solvent extraction (CSE) methods. The individual compounds of the optimized extract obtained by UAE were identified by ultra-high-performance liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (UHPLC-DAD-ESI-MSn). The yield of total phenolic compounds (TPC) was affected more significantly by ethanol concentration, irradiation time, liquid solvent-to-solid ratio (p < 0.0001) and amplitude (p = 0.0421) and optimal parameters conditions set by the RSM model were 70% (v/v), 7.5 min and 30%, respectively. The experimental yield of TPC (241.66 ± 12.77 mg gallic acid equivalent/g dry weight) confirmed the predicted value (235.52 ± 9.9 mg gallic acid equivalent/g dry weight), allowing also to confirm the model validity. Under optimized conditions, UAE was more efficient than MAE and CSE in extracting antioxidants, which comprised mostly myricetin glycosides. Globally, the present work demonstrated that, compared to MAE and CSE, UAE is an efficient method for phenolic extraction from M. communis pericarp, enabling to reduce the working time and the solvent consumption.
  • 14.

    【2hr】Optimization of Ultrasound-Assisted Extraction of Phenolic Compounds from Black Locust (Robiniae Pseudoacaciae) Flowers and Comparison with Conventional Methods

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    机译 超声辅助提取刺槐花中酚类化合物的工艺优化及与常规方法的比较
    摘要：The aim of this study was to optimize the ultrasound-assisted extraction of phenolic compounds from black locust (Robiniae pseudoacaciae) flowers using central composite design. The ethanol concentration (33–67%), extraction temperature (33–67 °C), and extraction time (17–33 min) were analyzed as the factors that impact the total phenolic content. The liquid-to-solid ratio of 10 cm3 g−1 was the same during extractions. The optimal conditions were found to be 59 °C, 60% (v/v) ethanol, and extraction time of 30 min. The total phenolic content (TPC = 3.12 gGAE 100 g−1 dry plant material) and antioxidant activity (IC50 = 120.5 µg cm−3) of the extract obtained by ultrasound-assisted extraction were compared with those obtained by maceration (TPC = 2.54 gGAE 100 g−1 dry plant material, IC50 = 150.6 µg cm−3) and Soxhlet extraction (TPC = 3.22 gGAE 100 g−1 dry plant material, IC50 = 204.2 µg cm−3). The ultrasound-assisted extraction gave higher total phenolic content and better antioxidant activity for shorter extraction time so that it represents the technique of choice for the extraction of phenolic compounds. The obtained extract, as the source of antioxidants, can be applied in the pharmaceutical and food industries.
  • 15.

    【2hr】Ectopic or Over-Expression of Class 1 Phytoglobin Genes Confers Flooding Tolerance to the Root Nodules of Lotus japonicus by Scavenging Nitric Oxide

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    机译 第1类植物珠蛋白基因的异位表达或过量表达通过清除一氧化氮赋予莲花莲根结节耐水性
    摘要：Flooding limits biomass production in agriculture. Leguminous plants, important agricultural crops, use atmospheric dinitrogen gas as nitrogen nutrition by symbiotic nitrogen fixation with rhizobia, but this root-nodule symbiosis is sometimes broken down by flooding of the root system. In this study, we analyzed the effect of flooding on the symbiotic system of transgenic Lotus japonicus lines which overexpressed class 1 phytoglobin (Glb1) of L. japonicus (LjGlb1-1) or ectopically expressed that of Alnus firma (AfGlb1). In the roots of wild-type plants, flooding increased nitric oxide (NO) level and expression of senescence-related genes and decreased nitrogenase activity; in the roots of transgenic lines, these effects were absent or less pronounced. The decrease of chlorophyll content in leaves and the increase of reactive oxygen species (ROS) in roots and leaves caused by flooding were also suppressed in these lines. These results suggest that increased levels of Glb1 help maintain nodule symbiosis under flooding by scavenging NO and controlling ROS.
  • 16.

    【2hr】Isolation of Strong Antioxidants from Paeonia Officinalis Roots and Leaves and Evaluation of Their Bioactivities

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    机译 Pa药根和叶中强抗氧化剂的分离及其生物活性评价
    摘要：Paeonia officinalis extracts from leaves and roots were tested for their antioxidant potential using in vitro chemical (Folin-Ciocalteu, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), oxygen radical absorbance capacity (ORAC), hydroxyl radical antioxidant capacity (HORAC), hydroxyl radical scavenging capacity HOSC)) and cellular antioxidant activity (CAA) assays. Leaf extracts were stronger antioxidants than root extracts, while methanol was a more effective solvent than water in chemical assays. However, the selected water extract of leaves was a stronger antioxidant in CAA than the methanol extract (0.106 vs. 0.046 µmol quercetin equivalents/mg). Twenty compounds were identified by ultra performance liquid chromatography-quadrupole-time-of-flight (UPLC-Q-TOF) mass spectrometer, while on-line screening of their antioxidant capacity by high performance liquid chromatography (HPLC) with a DPPH•-scavenging detector revealed that gallic acid derivatives are the major peony antioxidants. Root water and leaf methanol extracts inhibited α-amylase in a dose dependent manner. The IC50 value for the strongest inhibitor, the methanol extract of leaves, was 1.67 mg/mL. In addition, the cytotoxicity assessment of extracts using human Caco-2 cells demonstrated that none of them possessed cytotoxic effects.
  • 17.

    【2hr】Sesamol Inhibited Ultraviolet Radiation-Induced Hyperpigmentation and Damage in C57BL/6 Mouse Skin

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    机译 芝麻酚抑制C57BL / 6小鼠皮肤中紫外线辐射诱导的色素沉着和损伤
    摘要：Melanin is synthesized through a series of oxidative reactions initiated with tyrosine and catalyzed by melanogenesis-related proteins such as tyrosinase, tyrosinase-related protein-1 (TRP-1), dopachrome tautomerase (TRP-2), and microphthalmia-associated transcription factor (MITF). Our previous study demonstrated that sesamol inhibited melanin synthesis through the inhibition of the melanocortin 1 receptor (MC1R)/MITF/tyrosinase pathway in B16F10 cells. In this study, sesamol was applied to C57BL/6 mouse skin to understand its activity with respect to skin pigmentation. The results indicated that ultraviolet (UV) B-induced hyperpigmentation in the C57BL/6 mouse skin was significantly reduced by topical application of sesamol for 4 weeks. Sesamol reduced the melanin index and melanin content of the skin. In addition, sesamol elevated the brightness (L* value) of the skin. Sesamol also reduced UVB-induced hyperplasia of epidermis and collagen degradation in dermis. In immunohistochemical staining, topical application of sesamol reduced UVB-induced tyrosinase, TRP-1, TRP-2, and MITF expression in the epidermis of the skin. These results demonstrated that sesamol is a potent depigmenting agent in the animal model.
  • 18.

    【2hr】First Apocarotenoids Profiling of Four Microalgae Strains

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    机译 四种微藻菌株的首个Apocar​​otenoids分析
    摘要：Both enzymatic or oxidative carotenoids cleavages can often occur in nature and produce a wide range of bioactive apocarotenoids. Considering that no detailed information is available in the literature regarding the occurrence of apocarotenoids in microalgae species, the aim of this study was to study the extraction and characterization of apocarotenoids in four different microalgae strains: Chlamydomonas sp. CCMP 2294, Tetraselmis chuii SAG 8-6, Nannochloropsis gaditana CCMP 526, and Chlorella sorokiniana NIVA-CHL 176. This was done for the first time using an online method coupling supercritical fluid extraction and supercritical fluid chromatography tandem mass spectrometry. A total of 29 different apocarotenoids, including various apocarotenoid fatty acid esters, were detected: apo-12’-zeaxanthinal, β-apo-12’-carotenal, apo-12-luteinal, and apo-12’-violaxanthal. These were detected in all the investigated strains together with the two apocarotenoid esters, apo-10’-zeaxanthinal-C4:0 and apo-8’-zeaxanthinal-C8:0. The overall extraction and detection time for the apocarotenoids was less than 10 min, including apocarotenoids esters, with an overall analysis time of less than 20 min. Moreover, preliminary quantitative data showed that the β-apo-8’-carotenal content was around 0.8% and 2.4% of the parent carotenoid, in the C. sorokiniana and T. chuii strains, respectively. This methodology could be applied as a selective and efficient method for the apocarotenoids detection.
  • 19.

    【2hr】Effect of Manitoba-Grown Red-Osier Dogwood Extracts on Recovering Caco-2 Cells from H2O2-Induced Oxidative Damage

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    机译 曼尼托巴生长的红腰山茱wood提取物对H2O2诱导的氧化损伤中恢复Caco-2细胞的作用
    摘要：Red-osier dogwood, a native species of flowering plant in North America, has been reported to have anti-oxidative properties because of abundant phenolic compounds; this could be promising as a functional food or a feed additive. In the present study, an oxidative damage model using 1.0 mM hydrogen peroxide (H2O2) in Caco-2 cells was established to evaluate the antioxidative effects of red-osier dogwood extracts (RDE). The results showed that 1.0 mM H2O2 pre-exposure for 3 h significantly decreased cell viability, and increased interleukin 8 (IL-8) secretion and the intracellular reactive oxygen species (ROS) level. Caco-2 cells were treated with 100 µg/mL RDE for 24 h after pre-exposure to H2O2. It was found that the decreased cell viability caused by H2O2 was significantly restored by a subsequent 100 µg/mL RDE treatment. Furthermore, the IL-8 secretion and ROS level were significantly blocked by RDE, accompanied by the enhanced gene expression of hemeoxygenase-1 (HO-1), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), and the enhanced protein expression of the nuclear factor (erythroid-derived 2)-like 2 (Nrf-2). Moreover, RDE improved barrier functions in Caco-2 cells. Using RDE reduced the diffusion of fluorescein isothiocyanate (FITC)-dextran and increased the transepithelial resistance (TEER) value. The relative mRNA level of tight junction claudin-1, claudin-3, and occludin was elevated by RDE. These extracts also repaired the integrity of zonula occludens-1 (ZO-1) damaged by H2O2 and increased the protein expressions of ZO-1 and claudin-3 in the H2O2-pretreated cells. These results illustrated that RDE reduced the ROS level and enhanced the barrier function in oxidative-damaged epithelial cells.
  • 20.

    【2hr】Structure–Antioxidant–Antiproliferative Activity Relationships of Natural C7 and C7–C8 Hydroxylated Flavones and Flavanones

    包量

    机译 天然C7和C7-C8羟基化黄酮和黄酮的结构-抗氧化-抗增殖活性关系
    摘要：Common food flavonoids: chrysin, apigenin, luteolin, diosmetin, pinocembrin, naringenin, eriodictyol, hesperetin, and their analogues with an additional hydroxyl group at the C-8 position obtained via biotransformation were tested for antioxidant activity using the ABTS, DPPH, and ferric ion reducing antioxidant power (FRAP) methods. They were also tested for antiproliferative activity against selected human cancer cell lines—MV-4-11 (biphenotypic B myelomonocytic leukemia), MCF7 (breast carcinoma), LoVo (colon cancer), LoVo/DX (colon cancer doxorubicin resistant), and DU 145 (prostate cancer)—and two normal human cell lines—MCF 10A (breast cells) and HLMEC (lung microvascular endothelial cells). Flavonoids with a C7–C8 catechol moiety indicated much higher antioxidant activity compared with the C7 hydroxy analogues. However, because they were unstable under the assay conditions, they did not show antiproliferative activity or it was very low.
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