Antioxidant and anti-inflammatory polyphenols in ultrasound-assisted extracts from salvilla (Buddleja scordioides Kunth)

Salvilla is a widely distributed plant used in treatments against gastrointestinal disorders due to its phenolic antioxidant and anti-inflammatory potential. Major yield and quality of bioactive polyphenols must be obtained with no degradation during suitable processes such as Ultrasound-Assisted Extraction (UAE), which allows an efficient extraction of metabolites at appropriate parameter conditions. Salvilla extractions were made using UAE and aqueous ethanolic solutions. Variables used in UAE were sonication time, wave amplitude and percentage of ethanol in solvent. Extracts were tested for total flavonoids, antioxidant activity (ABTS, FRAP and ORAC) and an identification and quantification of phenolic compounds was carried out by UPLC-PDA-ESI-MS/MS. Once elected the better extraction conditions, an anti-inflammatory test was performed for this treatment. As a result, total flavonoids content in extracts was 147 to 288 µg catechin equivalents/mg of dry salvilla extract. All extracts have shown good antioxidant activity (86 to 280 mM Trolox eq/mg dry salvilla extract). Flavonoids contents by chromatography were higher than hydroxybenzoic and hydroxycinnamic acids specially the flavone, flavanol and flavanone groups. Treatment T6 (75% ethanol, 30% amplitude and 10 min extraction time) was the best extract in terms of significant flavonols, antioxidant activity, and higher anti-inflammatory potential.     

Effect of high hydrostatic pressure on phenolic compounds,ascorbic acid and antioxidant activity in cashew apple juice

The cashew apple is native to Brazil, but there is insufficient information regarding the nutritional properties of this fruit. The objective of this study was to evaluate the impact of high pressure processing (HPP) at room temperature (25 °C) on phenolic compound and ascorbic acid contents and antioxidant capacity of cashew apple juice. This study showed that HPP at 250 or 400 MPa for 3, 5 and 7 min did not change pH, acidity, total soluble solids, ascorbic acid or hydrolysable polyphenol contents. However, juice pressurized for 3 and 5 min showed higher soluble polyphenol contents. Antioxidant capacity, measured by the ferric-reducing antioxidant power method, was not altered by HPP, but when treated at 250 MPa for 3 min, it resulted in an increased value when 2,2-diphenyl-1-picrylhydrazyl was used. These data demonstrate that HPP can be used in the food industry for the generation of products with higher nutritional quality.     

Remarks on the order parameter of the cuprate high temperature superconductors

A large body of spectroscopic data on the cuprate high temperature superconductors (CHTSC) is reviewed in order to determine their order parameter. ASJ, INS, B_2g Raman spectra, optical data, NIS “dips”, ARPES “dips” and ARPES “kinks” all show the same excitation energy (40 meV for OP95 systems), proportional to the superconducting transition temperature, and it is therefore identified with the order parameter.     

Effect of solvent polarity on the Ultrasound Assisted extraction and antioxidant activity of phenolic compounds from habanero pepper leaves (Capsicum chinense) and its identification by UPLC-PDA-ESI-MS/MS

Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS⁺ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g⁻¹ dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS⁺ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with “ε” values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the “ε” of the solvents for future metabolomic studies.     

Extraction of bioactive compounds from defatted passion fruit bagasse (Passiflora edulis sp.) applying pressurized liquids assisted by ultrasound

Passion fruit bagasse is a rich source of phenolic compounds, including piceatannol, a stilbene to which several biological activities are conferred. This work reports the application of pressurized liquid extraction (PLE) assisted by ultrasound (US) to intensify the extraction of phenolic compounds from defatted passion fruit bagasse (DPFB). PLE at different temperatures (65–75 °C) without and with different US powers (240–640 W) was performed to investigate the mechanism of the assisted process. The extracts were evaluated in terms of global, total phenolic (TP), piceatannol and total reducing sugar yields. The antioxidant capacity of the extracts was determined by FRAP and ORAC assays. PLE assisted by US increased the yields, resulting in 60% more TP and piceatannol. The observed yields suggest that the main mechanism driving PLE assisted by US from DPFB was the rise in temperature caused by the ultrasonic waves. Pearson coefficient revealed a strong correlation between antioxidant capacity and total phenolics and piceatannol yield. The three-line spline model was adequately fitted to the experimental curves, showing three extraction periods in which the recovery of TP and piceatannol was higher than 70% at the end of the falling extraction rate period. PLE assisted or not by US showed to be clean, efficient and green alternatives for the recovery of phenolic compounds. The findings of this work indicate that PLE assisted by US has a great potential to improve the extraction of bioactive compounds from natural products.     

Impact of ultrasound-assisted extraction on quality and photostability of the Pothomorphe umbellata extracts

Pothomorphe umbellata (L.) Miq. is a Brazilian shrub with therapeutic and economic applications. There are some reports on the technological development of P. umbellata preparations; however, there are no studies on the influence of non-conventional extraction procedures on the quality of P. umbellata extracts. The aim of this study was to evaluate the effects of the ultrasound-assisted extraction (UE) parameters upon the extraction yield (EY%) of 4-nerolidylcatechol (4-NC) and the antioxidant activity of P. umbellata extracts using a factorial design and response surface methodology. Extracts obtained by UE and percolation were compared, and the photostability of 4-NC was evaluated via the exposure of UVA and visible light to the samples. The most influential variables observed for the UE were the ethanol-to-water and drug-to-solvent ratios. UE improved the extraction kinetics of 4-NC from plant material and improved the antioxidant activity of the extracts. Some of the ultrasound extracts showed an antioxidant activity that was not proportional to their 4-NC concentration, which suggests the presence of other active antioxidant compounds in these P. umbellata extracts. There was no significant difference in the photostability of 4-NC between the percolated and ultrasound extracts. Surprisingly, the isolated 4-NC material was significantly more stable when exposed to UVA-visible light compared to 4-NC in the plant extracts.     

Ultrasound-alkaline combined extraction improves the release of bound polyphenols from pitahaya (Hylocereus undatus 'Foo-Lon') peel: Composition,antioxidant activities and enzyme inhibitory activity

In this study, ultrasound-assisted alkaline hydrolysis was used to extract polyphenols from pitahaya peel. The effects of sonication time, ultrasonic density, NaOH concentration and the liquid–material ratio on the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of the extracts were studied. The composition and content difference of the extracts were analyzed and the inhibitory effect of α-amylase and α-glucosidase was measured. The results of single-factor analysis showed that when the sonication time was 45 min, the ultrasonic density was 32 W/L, the NaOH solution concentration was 6 M and the liquid–material ratio was 30 mL/g, the release of phenolic compounds was the largest and the antioxidant activity was the strongest. An UPLC-QTOF-MS/MS method was used to analyze the components and contents of the extracts. We found that there was a great difference in the component content of the free polyphenol extract and the bound polyphenol extract. From the results, we concluded that there was a strong correlation between the type and content of phenolic compounds and antioxidant activities, indicating that phenolic compounds were the main compounds of these biological activities. Moreover, the bound polyphenol extracts showed a significant inhibitory effect on α-amylase and α-glucosidase was stronger than that of the free polyphenol extracts. In addition, scanning electron microscopy showed that ultrasound-assisted extraction is crucial to the destruction of the cell wall and the release of bound polyphenols. Therefore, the pitahaya peel has the potential for therapeutic, nutritional, and functional food applications, and ultrasound-assisted alkaline hydrolysis is an effective means to release phenolic compounds.     

Comments on possible “B-site” disorder in A15 (β-W type) compounds

In a recent paper evidence for “preferential B-site disorder” in A15 compounds was presented. It can be shown, however, that the data in this paper lead to serious disagreements between predicted and observed phase compositions. Thus, the methods used are of doubtful validity and it is suggested that a more accurate knowledge of the phase compositions is needed.     

Synthetic metals: Applications of the Mössbauer effect and other methods

A review is given about the current activities in the field of the “synthetic metals”. This nomenclature is used for materials which consist basically of non-metallic components, but reach metallic conductivities by doping or intercalation reactions with additional components acting as donors or acceptors. Typical examples are conducting polymers like doped polyacetylene or graphite intercalation compounds. The contributions of Mössbauer studies in understanding the electronic, magnetic, and structural properties of such systems are outlined. Comparison with other spectroscopic methods is given in selected cases.     

4f-ionization of atomic cerium

The binding of the 4f electron in a cerium atom is investigated for general shapes of the 4f wave function. There is no activation barrier for 4f-ionization, in contradiction to an earlier calculation by Schlüter and Varma, who assumed a hydrogenic form. The existence of a second stationary electronic structure with extended 4f electrons and the “bistability model” developed from it to explain spectroscopic data in Ce compounds can be ruled out on energetic grounds.     

The photoelectron spectra of anti- and syn-[2.2](2,6)-azulenophanes

The He(Iα) photoelectron spectra of the title compounds are almost superposable, as predicted on the basis of a simple LCMO model which takes account of the “through-space” and “through-bond” interactions between the two azulene moieties. This observation, i.e., that the interaction of the two “layers” (decks) of the azulenophane molecule is independent of their relative orientation, may seem surprising in view of the fact that azulene is a polar molecule. However, the observed result indicates once more that azulene is essentially a perturbed [10]annulene rather than a “strongly” non-alternant hydrocarbon, a conclusion which had already been reached by the analysis of other spectroscopic properties of this molecule.     

Hot and Heavy Matters in the Foundations of Statistical Mechanics

Are the generalizations of classical equilibrium thermodynamics true of self-gravitating systems? This question has not been addressed from a foundational perspective, but here I tackle it through a study of the “paradoxes” commonly said to afflict such systems. My goals are twofold: (a) to show that the “paradoxes” raise many questions rarely discussed in the philosophical foundations literature, and (b) to counter the idea that these “paradoxes” spell the end for gravitational equilibrium thermodynamics.     

Multi-spectroscopic and molecular docking studies on the interaction of new phthalimides with calf-thymus DNA: In vitro free radical scavenging activities

ABSTRACT

In this study, we report the synthesis and biological evaluation of novel phthalimide based Schiff base derivatives as promising antioxidant and DNA-binding agents. The structural investigation of the synthesized compounds was determined by spectral and elemental analysis. In vitro DNA-binding studies of title compounds were carried out by UV–Vis, fluorescence, circular dichroism spectroscopic techniques, cyclic voltammetry, thermal denaturation studies, and hydrodynamic measurements to investigate their potential as DNA-binding agents. The DNA binding constant (K_b) of target compounds was obtained from absorption studies between 1.2 × 10⁵ M^?1 and 1.27 × 10⁵ M^?1, respectively, suggesting that the test compounds have shown good affinity toward calf-thymus DNA. The experimental results of DNA-binding studies reveal a non-intercalative mode of binding between DNA and the synthesized compounds, most probably groove binding. In addition, molecular docking techniques were performed to rationalize the observed binding affinities with the target DNA. Furthermore, antioxidant and free radical scavenging activities of the synthesized compounds were carried out to find out their pharmacological potential. The results indicate that the title compounds displayed good antioxidant activity against DPPH (IC₅₀: 0.727 and 0.656 mg/mL) and H₂O₂ radicals (IC₅₀: 1.072 and 0.911 mg/mL) comparable to standard ascorbic acid.     

铁苋菜不同提取物的抗氧化性及抑菌活性

研究了铁苋菜甲醇、70%乙醇、水3种提取物清除羟自由基(.OH)和超氧阴离子自由基(O-2·)的能力与总抗氧化能力(T-AOC)及其抑菌活性。结果表明:3种提取物中70%乙醇提取物的抗氧化活性最强,它对·OH和O-2·的清除能力以及T-AOC均高于甲醇和水提取物。3种提取物对大肠杆菌、金黄色葡萄球菌、表皮葡萄球菌、枯草芽孢杆菌、绿脓杆菌均有一定的抑制作用,抑菌圈直径均显著高于对照组,对表皮葡萄球菌的抑制作用最弱。水提取物对枯草芽孢杆菌的抑制作用弱于甲醇和70%乙醇提取物,甲醇提取物对大肠杆菌抑制作用强于70%乙醇和水提取物,3种提取物对金黄色葡萄球菌和绿脓杆菌的抑制效果无差异。     

基于支持向量机的玉米苗期田间杂草光谱识别

田间全面积均匀喷施除草剂不经济,还污染环境,精准喷施除草剂意义重大,其关键是正确识别杂草。用便携式野外光谱仪,在田间测量了玉米、马唐和稗草植株冠层在350～2 500 nm波长范围内的光谱数据,经过数据预处理,数据分析波长选为350～1 300和1 400～1 800 nm。数据处理采用支持向量机(SVM)模式识别方法。SVM具有可实现对小样本建模结构风险最小化、结果最优化、泛化能力强的优点。用线性、多项式、径向基和多层感知核函数对玉米和杂草建立二分类模型,结果表明,三阶多项式核函数SVM分类模型的正确识别率最高,达到80%以上,且支持向量比例较小。以二分类模型为基础,利用投票机制,建立了玉米、马唐和稗草的一对一多分类SVM模型,正确识别率达80%。田间光谱测量受光照、背景和仪器测量精度等条件的影响较大,但结果仍表明SVM结合光谱技术在田间杂草识别中应用潜力很大,此研究为田间杂草识别及传感器的建立提供了一种研究思路和应用基础。     

Ultrasonication-assisted synthesis of alcohol-based deep eutectic solvents for extraction of active compounds from ginger

An ultrasonication-assisted synthesis of alcohol-based deep eutectic solvents (DESs) is described. Several DESs were synthesized simultaneously under the same conditions. The prepared DESs were used for the extraction of gingerols from ginger powder via ultrasonication-assisted extraction. Notably, some of the prepared DESs exhibited superior extraction performance than those in traditional organic solvents. The viscosity of the DESs, which was suggested to be typically lower than 100 mPa*s had a critical effect on extraction performance. However, the higher gingerol contents in the extracts did not translate to higher active antioxidant abilities. The extraction temperature was found to be a key determinant of the antioxidant capability of the extracted gingerols while the use of higher temperatures (>50 °C) induced degradation and loss of phenolic compounds during extraction. Response surface methodology was applied for determining the optimal extraction conditions to achieve maximum antioxidant capacity with suitable gingerol content. All compounds used for the preparation of the DESs in this study have been widely employed in cosmetic and pharmaceutical fields. Therefore, the extracts in these DES solutions can be considered for direct application development without further product isolation.     

Bioactive characterization of ultrasonicated ginger (Zingiber officinale) and licorice (Glycyrrhiza Glabra) freeze dried extracts

Ginger (Zingiber officinale) and Licorice (Glycyrrhiza glabra L.) are one of the most popular spices having a wide range of bioactive compounds that have varied biological and pharmacological properties. The study was aimed to extract polyphenols from Himalayan medicinal herbs ginger and licorice in different solvents using ultra-sonication technique. The extraction efficiency (EE) was determined, and the extracts were characterized for physical properties (particle size, colour values), total phenolics, flavonoids, antioxidant properties, and structural and morphological features. Ultra-sonicated ginger in aqueous phase had the highest EE of polyphenols (15.27%) as compared to other solvents. Similar trend was observed in licorice with EE of 30.52 % in aqueous phase followed by ethanol: water (50: 50), and methanol: water (50:50) with 28.52% and 26.39%, respectively. The preliminary screening showed the presence of tannins, phenolics, flavonoids, saponins and carbohydrates, steroids and alkaloids in all the extracts. The phenolic and flavonoid content of dried ginger was found higher in ethanolic extracts compared to fresh ones as revealed by HPLC. Similarly, for licorice, the ethanolic fractions had the highest polyphenolic content. The representative samples of ginger (ethanol: water 75:25 and ethylacetate: water 75:25) and licorice (ethanol: water 70:30 and methanol: water 50:50) were studied for FESEM and particle size. The results showed the agglomerated extract micro-particles with a diameter of 0.5–10 µm and increased particle size (ginger: 547 and 766 nm), and (licorice: 450 and 566 nm). The findings could be beneficial for the advancement of ginger and licorice processing, for the comprehension of these herbs as a source of natural antioxidants in different food formulations.     

刺梨的活性成分含量分布与光谱表征

刺梨是蔷薇科蔷薇属多年生落叶灌木,其果实富含多种生物活性物质,具有重要的药食用价值。采用近红外、紫外-可见、激发发射三维荧光光谱技术系统性表征刺梨鲜果提取物化学组成,探讨不同产地的301个批次刺梨果中总酚、总黄酮、总三萜类物质的含量与自由基清除能力、铁离子还原能力等抗氧化活性的分布特征。结果显示刺梨果中具有高含量的酚类、黄酮类、三萜类物质,分别为9.23～37.45, 8.80～27.96和6.91～22.62mg·g^-1 FW(新鲜刺梨果的重量)。刺梨果具有较好的自由基清除活性和还原能力,对1,1-二苯基-2-三硝基苯肼(DPPH)清除率为14.39%～83.19%、 2,2’-联氮基-双-(3-乙基-苯并噻唑啉-6-磺酸)二铵盐(ABTS)清除率18.50%～68.45%、对铁离子还原能力(FRAP)0.08～0.44 mmol·L^-1 TE·g^-1 FW。这些物质含量与活性指标数据均服从正态分布,表明实验用的多批次刺梨样本具有多样性、代表性、随机性,并且不同产地的样本提取物的活性成分含量及抗氧化活性没有显著的统计学...     

增强的UV-B辐射对高粱幼苗光合和抗氧化系统的影响

由于臭氧层逐渐变薄,到达地球表面UV-B辐射不断增加,因UV-B辐射改变的太阳光谱将会对陆地植物造成不同程度的伤害。本试验以高粱龙杂5为材料,对二叶一心高粱进行四种剂量UV-B处理,恢复2 d采用光合仪测定光合参数,并取样测定抗氧化酶活性。随着UV-B剂量的升高,高粱叶片褐化损伤加重,植株矮化,鲜重和干重显著降低;花青素含量显著升高,叶绿素和类胡萝卜素含量显著减少,净光合速率和叶绿素荧光参数显著下降。同时,随UV-B剂量升高,高粱幼苗气孔导度、胞间CO₂浓度和蒸腾速率表现为“降-升-降”变化;POD和CAT活性呈现“降-升-降”变化;SOD和GR活性呈现“降-升”变化,APX和GPX呈现“升-降-升”变化。在供试的四种剂量中,UV-B处理6 h(相当2.4 J·m-2)的高粱幼苗净光合急剧下降,其他光合指标以及抗氧化酶活性也表现出明显转折。结果表明,增强的UV-B辐射直接导致高粱光合色素、净光合速率和叶绿素荧光参数的改变;高粱抗氧化系统对高、低剂量UV-B响应机制不同, 其中 ASA-GSH循环对低剂量UV-B反应更敏感,高剂量UV-B辐射不仅破坏高粱光合作用,而且启动植物酶促和非酶抗氧化系统,导致叶片褐化坏死,植株生物量累积减少、株高矮化,甚至死亡。     

Unusual Light Spectroscopic Properties of a 2-Pyridone-Based Multi-Ring-Fused Fluorescent Scaffold

UV-VIS absorption and fluorescence spectroscopic properties of six related polyaromatic 2-pyridones have been studied. Excitation of the lowest and rather weak and structure-less transition [ε _max (430 nm)?≈?3,000 mol^?1dm³cm^?1] gives rise to a broad fluorescence band in the visible region, for these compounds. These S ₀ ? S ₁ transitions are compatible with symmetrically forbidden transitions, promoted by intensity borrowing, as is revealed by fluorescence depolarisation data. With one exception, all compounds exhibit strong fluorescence, with quantum yields in glycerol varying between 40% and 70%. The corresponding fluorescence lifetimes range from 11 ns to 17 ns, while the radiative lifetimes are very similar (≈26 ns), for all compounds. Interestingly and rarely observed, the calculated radiative lifetimes for the weak absorption band are significantly longer, i.e. between 37 and 40 ns.