Paecilomyces variotii extract increases lifespan and protects against oxidative stress in Caenorhabditis elegans through SKN-1, but not DAF-16

A natural extract from Paecilomyces variotii (P. variotii extract, PVE), an endophytic fungus, has been used widely to improve agricultural crop performance and control multiple plant pathogens. Most recent studies focused on its application as a plant growth promoter, while relatively few studies have been reported on the antioxidant potential in vivo and the underlying mechanism. The present study was designed to determine the antioxidant activities of PVE and its mechanisms using Caenorhabditis elegans. Results showed that, compared to the solvent control, PVE at 1.0, 10 and 100 ng/mL significantly extended the lifespan of C. elegans by 36.60%, 59.80% and 53.30%, respectively. PVE at 10 ng/mL consistently promoted nematodes growth, but all treatments did not influence nematode fecundity, locomotion behavior, and pharyngeal pumping. Furthermore, PVE at the three tested concentrations significantly reduced accumulation of reactive oxygen species (ROS), lipofuscin, lipid and malondialdehyde (MDA) content, meanwhile significantly promoted activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) in the nematodes. Compared with the solvent control, PVE up-regulated gene expression of skn-1, mev-1, sod-3, and daf-2, but significantly down-regulated the expression of nhr-49 and daf-16. Further evidence revealed that PVE at the three concentrations significantly promoted nuclear localization of SKN-1, but not affected that of DAF-16, indicating the complex roles of DAF-16 and SKN-1 in stress resistance and longevity regulation. Overall, our results demonstrated that SKN-1 played a critical role in increasing lifespan of C. elegans and protecting the nematodes from oxidative stress, independent of DAF-16.     

One-pot esterification and amidation of phenolic acids

We developed a new one-pot reaction of phenolic acids to afford the corresponding esters and amides through acyl-protected and activated phenolic acid intermediates. The simultaneous protection/activation of phenolic acids with alkylchloroformates proceeded readily in the presence of DMAP at room temperature; subsequent addition of alcohols or amines afforded the corresponding esters or amides. The use of iso-butyloxycarbonyl as the protecting and activating group in the one-pot reactions afforded phenolic esters or amides in 91% average yield. As a practical example of this convenient synthesis, caffeic acid phenethyl ester (CAPE) was readily synthesized from commercially available caffeic acid and phenethyl alcohol in 95% yield, and an isotopomer of CAPE, [3,10-¹³C₂]CAPE, was synthesized in 91% yield from [3-¹³C]caffeic acid and 2-[1-¹³C]phenethyl alcohol. This method may be useful for the convenient esterification and amidation of diverse phenolic acids.     

Complexation of Caffeic and Ferulic Acids by Transition-Metal Ions

Potentiometric titration and IR and UV spectroscopies are used to study complexation of caffeic and ferulic acids by metal ions. Caffeic and ferulic acids, which occur in lignin, are shown to react with metal ions mainly through an ionic mechanism. However, coordination bonding is also possible depending on the nature of the ligand and metal ion and the ratio of starting components. The strongest complex forms between caffeic acid and CuCl ₂ (2:1 ratio)     

Determination of phenolic acids using Trametes versicolor laccase

Two biosensors based on Trametes versicolor laccase (TvL) were developed for the determination of phenolic compounds. Commercial oxygen electrode and ferrocene-modified screen-printed graphite electrodes were used for preparation of laccase biosensors. The systems were calibrated for three phenolic acids. Linearity was obtained in the concentration range 0.1-1.0 μM caffeic acid, 0.05-0.2 μM ferulic acid, 2.0-14.0 μM syringic acid for laccase immobilised on a commercial oxygen electrode and 2.0-30.0 μM caffeic acid, 2.0-10.0 μM ferulic acid, 4.0-30.0 μM syringic acid for laccase immobilised on ferrocene-modified screen-printed electrodes. Furthermore, optimal pH, temperature and thermal stability studies were performed with the commercial oxygen electrode. Both electrodes were used for determination of a class of phenolic acids, achieving a cheap and fast tool and an easy to be used procedure for screening real samples of human plasma.     

Photodegradation of Caffeic Acid in W/O/W Emulsions in the Absence and in the Presence of TiO2

Caffeic acid, a natural phenol with antioxidant and sunscreen activity, can undergo photooxidation upon UV irradiation. The photodegradation of caffeic acid at different concentrations was assessed in water, at pH 4.0 and 6.0, without and with TiO₂. The study was then carried out on W/O/W emulsions entrapping the phenolic acid either in the inner or in the outer aqueous phase in the absence and in the presence of TiO₂, added in the external phase (pH 6.0 or 7.0). The degradation of caffeic acid followed a pseudo-zero order kinetic with an inverse dependence from its initial concentration; at increasing pH of the medium caffeic acid degraded faster. The addition of TiO₂ increased the initial photodegradation rate. Compared with water, W/O/W emulsions protected the phenol towards both the photodegradation and the photocatalytic activity of TiO₂. Multiple systems allowed to incorporate caffeic acid and TiO₂ in the same formulation avoiding any catalytic interactions.     

The potential antioxidant ability of hydroxytyrosol on Caenorhabditis elegans against oxidative damage via the insulin signaling pathway

Hydroxytyrosol (HY) deriving from olive leaves is a phenolic component which has been proven to possess a strong antioxidant ability. However, the underling mechanism is still unclear. To evaluate the antioxidant ability of HY comprehensively, assays in vitro and in vivo (Caenorhabditis elegans (C. elegans) was used as a model organism) were conducted. The results showed HY could scavenge 2,2-Diphenyl-1-picryl-hydrazyl (DPPH) radicals with a strong total reducing power. Pretreated with HY for 48 h, the cell viability of Chinese hamster ovary (CHO) cells was enhanced under oxidative stress by reducing the level of reactive oxygen species (ROS) and malondialdehyde (MDA). A suitable concentration of HY showed no side effects on the development, fertility, and movement of C. elegans. With the treatment of HY, the survival was enhanced by 15.79% under thermal stress. The ROS and MDA contents were also reduced, which might be associated with the increasing abilities of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and the heat shock protein HSP-16.2. Nuclear localization of DAF-16 was greatly increased after treated with HY. More outcomes demonstrated HY exhibited an excellent antioxidant capacity via the insulin signaling pathway by upregulating daf-16 and sod-3 and downregulating the genes of age-1 and daf-2.     

Cinnamides Target Leishmania amazonensis Arginase Selectively

Caffeic acid and related natural compounds were previously described as Leishmania amazonensis arginase (L-ARG) inhibitors, and against the whole parasite in vitro. In this study, we tested cinnamides that were previously synthesized to target human arginase. The compound caffeic acid phenethyl amide (CAPA), a weak inhibitor of human arginase (IC₅₀ = 60.3 ± 7.8 μM) was found to have 9-fold more potency against L-ARG (IC₅₀ = 6.9 ± 0.7 μM). The other compounds that did not inhibit human arginase were characterized as L-ARG, showing an IC₅₀ between 1.3–17.8 μM, and where the most active was compound 15 (IC₅₀ = 1.3 ± 0.1 μM). All compounds were also tested against L. amazonensis promastigotes, and only the compound CAPA showed an inhibitory activity (IC₅₀ = 80 μM). In addition, in an attempt to gain an insight into the mechanism of competitive L-ARG inhibitors, and their selectivity over mammalian enzymes, we performed an extensive computational investigation, to provide the basis for the selective inhibition of L-ARG for this series of compounds. In conclusion, our results indicated that the compounds based on cinnamoyl or 3,4-hydroxy cinnamoyl moiety could be a promising starting point for the design of potential antileishmanial drugs based on selective L-ARG inhibitors.     

Hydrogen bonding of catechol groups in the crystal structure of dihydrocaffeic acid

Dihydrocaffeic acid C₉H₁₀O₄ is a natural antioxidant. The crystal structure of dihydrocaffeic acid is determined; the crystallographic data at 100 K are: a = 11.3189(4) Å, b = 5.5824(1) Å, c = 13.8431(4) Å, β = 109.248(4)°, and V = 825.80(4) ų; the space group is P2₁/c, Z = 4. In addition to the formation of hydrogen bonds that are typical of acids, the compound has features that are important from the viewpoint of reactivity of dihydrocaffeic acid molecules. The position of one of the hydroxyl hydrogen atoms in the catechol group is disordered even at 100 K. The crystal structure of caffeic acid does not show such a disordering.     

Phenolic Extract from Aralia nudicaulis L. Rhizomes Inhibits Cellular Oxidative Stresses

UV-B and IR-A radiation are important inducers of biological changes in skin involving ROS generation. The overloading of antioxidant defense mechanisms by ROS production could lead to photoaging and photocarcinogenesis processes. Various traditional usages are reported for Aralia nudicaulis L. extracts, including treatment of dermatological disorders. Antioxidant and anti-inflammatory properties have already been reported for other Aralia species possibly due to the presence of phenolic compounds. However, the phenolic composition and the potential activity of A. nudicaulis rhizomes extract against oxidative stress and UV/IR damages have not been investigated. The main aims of this study were to prepare a fraction enriched in phenolic compounds (FEPC) from A. nudicaulis rhizomes, to identify its major phenolic compounds and to assess its potential for protective effects against oxidative stress induced by UV-B, IR-A or inflammation. A quantitative LC-MS study of FEPC shows that chlorogenic, caffeic and protocatechuic acids are the main phenolic compounds present, with concentrations of 15.6%, 15.3% and 4.8% of the total composition, respectively. With a validated analytical method, those compounds were quantified over different stages of the growing period. As for biological potential, first this extract demonstrates antioxidant and anti-inflammatory activities. Furthermore, ROS generation induced by IR-A and UV-B were strongly inhibited by A. nudicaulis extract, suggesting that Aralia nudicaulis L. rhizome extract could protect dermal cells against oxidative stress induced by UV-B and IR-A.     

Comparison of Phenolic Profile of Balsamic Vinegars Determined Using Liquid and Gas Chromatography Coupled with Mass Spectrometry

Balsamic vinegar is one of the best known and most popular types of vinegar, and it is a rich source of polyphenolic compounds. The quality of balsamic vinegar as well as the content of phenolic substances vary depending on the production method. In the present work, we have developed a method for comprehensive characterization of the content of phenolic compounds in balsamic vinegars based on the combination of gas chromatography (GC) and high-performance liquid chromatography (HPLC) coupled with mass spectrometric detection in single mode (MS) and tandem mode (MS/MS). In total, 14 samples of different types of balsamic vinegar were analyzed without difficulty in sample preparation. The separation conditions and detection parameters of HPLC-MS/MS were optimized and used for the determination of 29 phenolic compounds and 6 phenolic acids. The profile of phenolic compounds was completed by semi-quantitative analysis of volatile organic compounds using GC-MS after optimized headspace solid-phase microextraction. Gallic acid, protocatechuic acid, caffeic acid, and p-coumaric acid have been identified as the major phenolic compounds in balsamic vinegars.     

Analyzing the Synergistic Effects of Antioxidants in Combating Photoaging Using Model Nematode,Caenorhabditis elegans

Aging, a universal and unique process, occurs both intrinsically (chronological) and extrinsically (photoaging). Ultraviolet-A (UV-A)-mediated stress is a growing health hazard to mankind as it is the major cause of photoaging, which could lead to much damage of skin cells and tissues ranging from tan, burn, or even cancer. The present study focuses on the role of antioxidants and other natural compounds which have been widely used in oral/topical applications to combat and delay the effects of photoaging using model nematode Caenorhabditis elegans. Compounds like green tea extract, naringenin, and naringin, which are known for their antioxidant properties, were able to extend life span and healthspan of the nematode in normal as well as under UV-A-mediated stress conditions. Regulation of both the stress-responsive genes (skn-1 and sir-2.1) and the aging-regulating genes (daf-2 and age-1) was attributable for these conditions. Interestingly, it was observed that these compounds when combined in equal ratios by weight worked synergistically to combat the aging process. Pronounced synergistic effects were observed during UV-A-mediated stress conditions, suggesting that these could be used as potential antiphotoaging compounds which will be of greater significance for health-based research.     

Phenolic Constituents of Lamium album L. subsp. album Flowers: Anatomical,Histochemical, and Phytochemical Study

Flos Lamii albi has a high biological activity and is widely used in herbal medicine. The aim of the study was to characterize the secretory structures present in Lamium album subsp. album corolla and the location of phenolic compounds. Additionally, we carried out qualitative phytochemical analyses of flavonoids and phenolic acids. Light, fluorescence, and scanning electron microscopy were used to analyze the structure of the floral organs. The main classes of phenolic compounds and their localization were determined histochemically. Phytochemical analyses were performed with high-performance thin-layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC). Six types of glandular trichomes were found which contained flavonoids, phenolic acids, and tannins. The phytochemical studies demonstrated the presence of caffeic, chlorogenic, ferulic, gallic, p-coumaric, protocatechuic, syringic, gentisic, and vanillic phenolic acids as well as rutoside, isoquercetin, and quercetin flavonoids. The corolla in L. album subsp. album has antioxidant properties due to the presence of various polyphenols, as shown by the histo- and phytochemical analyses. The distribution and morphology of trichomes and the content of phenolic compounds in the corolla have taxonomic, pharmacognostic, and practical importance, facilitating the identification of the raw material.     

Simultaneous Determination of Five Phenolic Compounds in Dried Flowers by LC Using DAD Combined Electrochemical Detection

A simple, sensitive and accurate method for the simultaneous separation and determination of apigenin and four phenolic acids including chlorogenic acid, caffeic acid, p-coumaric acid and ferulic acid in four dried flowers by high performance liquid chromatography with electrochemical detection (ECD) and diode array detection (DAD) has been established. The detection limits of caffeic acid, p-coumaric acid and ferulic acid obtained with ECD were 3, 1 and 4 ng mL^?1, and LOD of apigenin and chlorogenic acid obtained with DAD were 1 × 10^?2 and 6 × 10^?2 μg mL^?1. The detection and quantification limits of three phenolic compounds obtained with ECD were two to ninefold greater than those obtained with DAD. As electrochemically inactive compounds, apigenin and chlorogenic acid were detected by DAD. All calibration curves showed good linearity (r ≥ 0.9992) within the test ranges. The recoveries ranged from 95.3 to 101.4% (RSD ≤ 2.9%). This approach could provide scientific evidence for comprehensive evaluation about the effect of the medicine and ensure nutrient status of dried flowers.     

Study on phenolic acids of Lonicerae japonicae Flos based on ultrahigh performance liquid chromatography-tandem mass spectrometry combined with multivariate statistical analysis

Lonicerae japonicae Flos, a traditional Chinese medicine, has the function of evacuating heat and detoxifying. To promote the optimization of Lonicerae japonicae Flos germplasms and improve the quality of medicinal materials, 55 batches of five Lonicerae japonicae Flos germplasms with the same origin were collected during different periods, a UHPLC-TOF-MS method was established, and 22 kinds of phenolic acids were found and qualitatively analysed. Seventeen phenolic acids were selected for quantitative analysis by UHPLC-QqQ-MS/MS, and the quantitative results were analysed by principal component analysis, orthogonal partial least squares-discriminant analysis, and partial least squares discriminant analysis. The contents of phenolic acids in periods S1–S6 were found to be significantly different. There were also significant differences in the accumulation of phenolic acids in Lonicerae japonicae Flos during different growth periods. Ferulic acid, 5-O-caffeoylquinic acid, and caffeic acid were determined to be important components to distinguish the different growth periods of Lonicerae japonicae Flos. There were significant differences in the phenolic acid content of different germplasms of Lonicerae japonicae Flos, and the total amount of 17 phenolic acids and total acids (chlorogenic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid) in “Hua Jin No. 6” was highest, so the quality of “Hua Jin No. 6” was better than that of the four other germplasms. In addition, chlorogenic acid methyl ester and caffeic acid were the smallest markers in combination to distinguish the five germplasms of Lonicerae japonicae Flos.     

Content of Phenolic Compounds in Meadow Vegetation and Soil Depending on the Isolation Method

The aim of this paper was to determine the effect of the hydrolysis method on the amounts of phenolic compounds in the plant material in soil and, as a consequence, on the parameters to determine the degree of lignins transformation in soils. The study included the plant material (hay, sward, and roots) and soil—Albic Brunic Arenosol (horizon A, AE, and Bsv) samples. Phenolic compounds were isolated at two stages by applying acid hydrolysis followed by alkaline re-hydrolysis. The quantitative and qualitative analysis of phenolic compounds was performed with high-performance liquid chromatography with a DAD. The content of phenolic compounds in the extracts depended on the hydrolysis method and it was determined by the type of the research material. The amounts of phenolic compounds contained in the alkaline hydrolysates accounted for 55.7% (soil, horizon Bsv)—454% (roots) of their content in acid hydrolysates. In the extracts from acid hydrolysates, chlorogenic and p-hydroxybenzoic acids were dominant. In the alkaline extracts from the plant material, the highest content was recorded for p-coumaric and ferulic acids, and in the extracts from soil, ferulic and chlorogenic acids. A combination of acid and alkaline hydrolysis ensures the best extraction efficiency of insoluble-bound forms of polyphenols from plant and soil material.     

Changes in Organic Acids,Phenolic Compounds,and Antioxidant Activities of Lemon Juice Fermented by Issatchenkia terricola

High content of citric acid in lemon juice leads to poor sensory experience. The study aimed to investigate the dynamics changes in organic acids, phenolic compounds, and antioxidant activities of lemon juice fermented with Issatchenkia terricola WJL-G4. The sensory evaluation of fermented lemon juice was conducted as well. Issatchenkia terricola WJL-G4 exhibited a potent capability of reducing the contents of citric acid (from 51.46 ± 0.11 g/L to 8.09 ± 0.05 g/L within 60 h fermentation) and increasing total phenolic level, flavonoid contents, and antioxidant activities compared to those of unfermented lemon juice. A total of 20 bioactive substances, including 10 phenolic acids and 10 flavonoid compounds, were detected both in fermented and unfermented lemon juice. The lemon juice fermented for 48 h had better sensory characteristics. Our findings demonstrated that lemon juice fermented with Issatchenkia terricola exhibited reduced citric acid contents, increased levels of health-promoting phenolic compounds, and enhanced antioxidant activities.     

iso-Fatty Acid Metabolism in Caenorhabditis elegans’ Ceramide Biosynthesis

Ceramide biosynthesis and its connection to iso-fatty acid metabolism in the model organism Caenorhabditis elegans was investigated using a combination of reverse genetics and comparative ESI-(+)-HR-MS^e ceramide profiling along with incorporation experiments with bacterial mutants specifically enriched with isotopically labeled branched-chain amino acids or branched-chain fatty acids. Incorporation of a l -leucine-derived isovalerate unit into the conserved d17 : 1iso sphingosine building block proceeds through elo-5 dependent chain elongation and depends on peroxisomal β-oxidation by the 3-ketoacyl-CoA thiolase daf-22, although ceramide profiles of N2 wildtype and daf-22(ok693) are indistinguishable. Biosynthesis of the homologous N-iso-acyl moieties also depends on l -leucine and isovalerate chain elongation but proceeds independently of elo-5 and daf-22. Biosynthesis of the dominating N-docosanoyl moiety depends on elo-3-catalyzed chain elongation of bacteria-derived palmitic acid, whereas the N-tetracosanoyl moiety is derived from de novo lipogenesis.     

肉桂酸及其衍生物对活性氧H2O2清除作用

活性氧分子在生物内所引起的脂质过氧化可造成组织和细胞的损伤。因此,从天然产物中寻找抗活性氧的物质已引起国内外广泛重视。本文采用化学发光分析法,利用H2O2-CTMAB-鲁米诺发光体系,研究了中草药有效成分咖啡酸、氯原酸、连翘酯甙、阿魏酸、对．羟基香豆酸、间-羟基香豆酸、肉桂酸抗活性氧H2O2的作用。并与公认的抗活性氧物质抗坏血酸(Vc)进行了比较。