A Comparative Study on Polyphenolic Composition of Berries from the Tibetan Plateau by UPLC‐Q‐Orbitrap MS System

Five traditional medicinal food from the Tibetan plateau including Nitraria tangutorum Bobrov (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum Murray (LR), Lycium barbarum L. (LB) and Rubus corchorifolius L.f. (RC) are rich in phenolic compounds. However, the detailed studies about the phenolic compounds remain scarce. Therefore, we established a rapid method for the simultaneous identification and quantification of the phenolic compounds from berries via Ultra Performance Liquid Chromatography‐Quadruple‐Orbitrap MS system (UPLC‐Q‐Orbitrap MS). This method was verified from many aspects including detection limit, quantification limit, precision, repeatability, stability, average recovery rate and recovery range, and then was used to analyze the phenolic compounds in these five species of berries. Finally, a total of 21 phenolic compounds were directly identified by comparing the retention time and exact mass, of which 14 compounds were identified by us for the first time in berries from the Tibetan plateau, including one flavonoid aglycone (myricetin), 11 phenolic acids (gallic acid, protocatechuate, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, p‐coumaric acid, ferulic acid, 2‐hydroxybenzeneacetic acid and ellagic acid), one flavanol (catechin) and one dihydrochalcone flavonoid (phloretin). Quantitative results showed that rutin, myricetin, quercetin and kaempferol were the main flavonoids. Moreover, a variety of phenolic acid compounds were also detected in most of the berries from the Tibetan plateau. Among these compounds, the contents of protocatechuate and chlorogenic acid were high, and high levels of catechin and phloretin were also detected in these plateau berries.     

Three New Phenolic Amides from the Roots of Eggplant (Solanum melongena L.)

The isolation of four phenolic amides, four phenolic compounds and an aromatic amine from the roots of eggplant is described. The phenolic amides were identified as N-trans-feruloyl tyramine (V), N-trans-p-coumaroyl tyramine (VII), N-trans-feruloyl octopamine (VIII) and N-trans-p-coymaroyl octopamine (IX). The three amides V, VIII and IX are new compounds. Furthermore, four phenolic compounds were identified as vanillin (I), isoscopoletin (II), ethyl caffeate (IV) and ferulic acid (VI). The aromatic amine was identified as p-aminobenzal-dehyde (III).     

Time course study on accumulation of cell wall-bound phenolics and activities of defense enzymes in tomato roots in relation to <Emphasis Type="Italic">Fusarium</Emphasis> wilt

Major cell wall-bound phenolic compounds were detected and identified in roots of tomato at different stages of growth. Alkaline hydrolysis of the cell wall material of the root tissues yielded ferulic acid as the major bulk of the phenolic compounds. Other phenolic compounds identified were 4-hydroxybenzoic acid, vanillic acid, 4-hydroxybenzaldehyde, vanillin and 4-coumaric acid. All the six phenolic acids were higher in very early stage of plant growth. Ferulic acid, 4-hydroxybenzoic acid and 4-coumaric acid exhibited a decreasing trend up to 60 days and then the content of these phenolic acids increased somewhat steadily towards the later stage of growth. Total phenolics, phenylalanine ammonia-lyase (PAL) activity and peroxidase (POD) activity were in tandem match with the occurrence pattern of the phenolic acids. Ferulic acid showed highest antifungal activity against tomato wilt pathogen Fusarium oxysporum f. sp. lycopersici. The results of this study may be interpreted to seek an explanation for high susceptibility of tomato plants at flowering stage to Fusarium wilt. It may also be concluded that greater amounts of ferulic acid in combination with other phenolics and higher level of PAL and POD activities after 60 days of growth may have a role in imparting resistance against Fusarium wilt at a late stage of plant growth.     

Phenolic Content in Male and Female Carica papaya: A Possible Physiological Marker for Sex Identification of Vegetative Seedlings

The phenolic composition was determined in the leaves, petioles and bark tissues of male and female plants of two papaya cultivars. The same kind of phenolics were isolated from the male and female plants. However, a marked difference was observed between the plant organs of different cultivars. The important free and bound phenolics extracted after acidic and alkaline hydrolysis were caffeic acid, gentisic acid, m-coumaric acid, p-coumaric acid, salicylic acid and quercetin. Four phenolic compounds were not identified. The amounts of free, acid-hydrolysable and alkali-hydrolysable phenolic compounds were considerably higher in male plants.     

Antifungal phenolic acids in apple fruits after infection with Sclerotinia fructigena

Several compounds were separated from the antifungal materials produced in Edward VII apple fruits attacked by the brown rot organism Sclerotinia fructigena. Six phenolic compounds were isolated in the crude state by column chromatography and their fungicidal properties examined. Two of the phenolic acids present were purified and identified as 4-hydroxybenzoic acid and 4-hydroxy-3-methoxybenzoic acid. These phenolic compounds were shown to arise from the action of the pathogen on the juice of the fruit and not from the peel or the juice-free pulp.     

Constituents of Cane Molasses

By gas chromatography the following eight phenolic compounds and benzoic acid were identified from a sample of cane final molasses using both polar and non-polar stationary phases: anisole, phenetole, phenol, m-cresol, salicylic acid, resorcinol, vanillic acid, and syringic acid. The peaks corresponding to p-coumaric acid and vanillin were also found using non-polar phase. The structures of four or five unidentified components were inferred from the relation between retention temperature and functional group number of the phenolic compounds.     

The effect of phenols on respiratory enzymes in seed germination

Low molecular weight phenolic compounds were identified in two soilswith different vegetative cover, Fagus sylvatica, L. andPinus laricio, Poiret, spp. calabrica, and were tested atdifferent concentrations on seed germination of Pinuslaricio, and on respiratory and oxidative pentose phosphate pathwayenzymes involved in the first steps of seed germination. The data obtained showthat there are marked differences in the phenolic acid composition of the twoinvestigated soils. All the phenolic compounds bioassayed inhibited seedgermination and those extracted from Pinus laricio soilwere particularly inhibitory. We also found that the non-germination of seedsisstrongly correlated to the inhibition of the activities of enzymes ofglycolysisand the oxidative pentose phosphate pathway.     

Metabolic characterization of a strain (BM90) of <Emphasis Type="Italic">Delftia tsuruhatensis</Emphasis> showing highly diversified capacity to degrade low molecular weight phenols

A novel bacterium, strain BM90, previously isolated from Tyrrhenian Sea, was metabolically characterized testing its ability to use 95 different carbon sources by the Biolog system. The bacterium showed a broad capacity to use fatty-, organic- and amino-acids; on the contrary, its ability to use carbohydrates was extremely scarce. Strain BM90 was identified and affiliated to Delftia tsuruhatensis by molecular techniques based on 16S rRNA gene sequencing. D. tsuruhatensis BM90, cultivated in shaken cultures, was able to grow on various phenolic compounds and to remove them from its cultural broth. The phenols used, chosen for their presence in industrial or agro-industrial effluents, were grouped on the base of their chemical characteristics. These included benzoic acid derivatives, cinnamic acid derivatives, phenolic aldehyde derivatives, acetic acid derivatives and other phenolic compounds such as catechol and p-hydroxyphenylpropionic acid. When all the compounds (24) were gathered in the same medium (total concentration: 500 mg/l), BM90 caused the complete depletion of 18 phenols and the partial removal of two others. Only four phenolic compounds were not removed. Flow cytometry studies were carried out to understand the physiological state of BM90 cells in presence of the above phenols in various conditions. At the concentrations tested, a certain toxic effect was exerted only by the four compounds that were not metabolized by the bacterium.     

Profiling and Elucidation of the Phenolic Compounds in the Aerial Parts of Gynura bicolor and G. divaricata Collected from Different Chinese Origins

Gynura bicolor and G. divaricata are not only known to be nutritive as cultured vegetables, but also beneficial as folk medicines in East Asia. As demonstrated by the current phytochemical knowledge, the genus Gynura is a promising source of phenolics with multiple medicinal activities. To expand this phytochemical knowledge, the phenolic secondary metabolites of G. bicolor and G. divaricata were studied. From the aerial parts of these two species, collected in five different Chinese locations, two fractions of phenolic compounds with different polarity were obtained by extraction and chromatographic separation. Using UPLC/MS/MS analysis, a total of 53 phenolics were either identified by comparison with respective reference compounds or tentatively characterized by their chromatographic behavior, UV‐absorption patterns, and MS fragmentations. Some naturally existing positional isomers of O‐caffeoylquinic acid, O‐p‐coumaroylquinic acid, O‐feruloylquinic acid, and dicaffeoylquinic acid as well as their methyl esters were qualitatively characterized by their specific fragmentation patterns in targeted MS/MS. In addition, the aerial parts of the two Gynura species contained kaempferol, quercetin oligoglycosides, and a variety of derivatives of benzoic acid, hydroxycinnamic acid, and caffeic acid. Furthermore, the distribution of phenolic compounds in the two species from different Chinese origins was discussed. Finally, an investigation of the total phenolic content and in vitro antioxidant activity of the various phenolic fractions was completed, to evaluate the potential of the extracts of these species for medicinal development. The free‐radical‐scavenging activities of the extracts derived from plants originating from Nanjing were proven to be higher than those of the other extracts, which correlated well with their total phenolic content.     

Phytochemical Content,Antidiabetic, Anticholinergic,and Antioxidant Activities of Endemic Lecokia cretica Extracts

The aim of this work was to investigate the enzyme inhibition, antioxidant activity, and phenolic compounds of Lecokia cretica (Lam .) DC. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α‐glycosidase enzymes were strongly inhibited by the L. cretica extracts. IC₅₀ values for the three enzymes were found as 3.21 mg/mL, 2.1 mg/mL, and 2.07 mg/mL, respectively. Antioxidant activities were examined in both aqueous and ethanol (EtOH) extracts using CUPRAC, FRAP, and DPPH method. Also, the phenolic compounds of the endemic plant were identified and quantified by using HPLC/MS/MS. According to the results, the extracts have remarkable antioxidant activities. The most abundant phenolic acids of L. cretica in EtOH extract were determined as quinic acid (12.76 mg/kg of crude extract), chlorogenic acid (3.39 mg/kg), and malic acid (2.38 mg/kg).     

Phenolic composition and antioxidant activities of two Phlomis species: A correlation study

Two traditional Chinese medicines (Phlomis umbrosa Turcz. and Phlomis megalantha Diels), as well as five pure phenolic compounds (protocatechic, chlorogenic, benzoic, rosmarinic acid, and rutin) have been studied for antioxidant activities in acetone and methanol extracts from leaves. An HPLC method was developed to quantify the amounts of 14 phenolic compounds in the leaf extracts. The antioxidant capacities of the studied species are high. Almost all samples were capable of directly scavenging DPPH and superoxide free radicals, inhibiting linoleic acid oxidation, acting as reducing agents, and reducing plasmid DNA damage induced by hydroxyl radicals. Among different extracts, the acetone extract of P. megalantha exhibited the highest antioxidant activity. The major phenolic compounds identified were protocatechic, chlorogenic, caffeic, rosmarinic acid, and (−)-epicatechin. Antioxidant activities of pure compounds and correlation analysis indicated that protocatechic and rosmarinic acids were the major contributors to the observed antioxidant activities of the investigated Phlomis extracts. To cite this article: Y. Zhang, Z.-z. Wang, C. R. Biologies 332 (2009).     

BIOGENIC AMINES AND THEIR METABOLITES AS SUBSTRATES FOR PHENOL SULPHOTRANSFERASE (EC 2.8.2.1) OF BRAIN AND LIVER

Phenol sulphotransferase activity in homogenates of rat liver and brain was determined spectrophotometrically. Rat liver had about 100-fold more phenol sulphotransferase activity than brain; however, both tissues showed about the same spectrum of activity towards the phenolic compounds tested. Dopamine and its acidic and neutral metabolites and the neutral metabolites of norepinephrine were the compounds most readily sulphury-lated in vitro. They were also the compounds most readily sulphurylated in vivo when they were injected intraventricularly together with labelled Na₂SO₄. When labelled Na₂SO₄ was injected alone, we detected conjugation of endogenous phenols. One of the compounds formed was identified by its chromatographic characteristics as 3-methoxy-4-hydroxy-phenylethyleneglycol sulphate. We detected other conjugates which appeared to be the sulphate esters of 3,4-dihydroxyphenylethyleneglycol; 3,4-dihydroxyphenylacetic acid; and homovanillic acid. In brain, sulphate conjugation may be a major route of metabolism for many of the phenolic compounds related to the biogenic amines and possibly for phenolic drugs which enter the brain.     

Biodepollution of wastewater containing phenolic compounds from leather industry by plant peroxidases

This study deals with the use of peroxidases (POXs) from Allium sativum, Ipomoea batatas, Raphanus sativus and Sorghum bicolor to catalyze the degradation of free phenolic compounds as well as phenolic compounds contained in wastewater from leather industry. Secretory plant POXs were able to catalyze the oxidation of gallic acid, ferulic acid, 4-hydroxybenzoic acid, pyrogallol and 1,4-tyrosol prepared in ethanol 2% (v:v). Efficiency of peroxidase catalysis depends strongly on the chemical nature of phenolic substrates and on the botanical source of the enzymes. It appeared that POX from Raphanus sativus had the highest efficiency. Results show that POXs can also remove phenolic compounds present in industrial wastewater such as leather industry. Removal of phenolic compounds in wastewater from leather industry by POX was significantly enhanced by polyethylene glycol.     

Characterization of nitrated phenolic compounds for their anti-oxidant, pro-oxidant, and nitration activities

Coffee is one of the most widely consumed beverages worldwide. Evidence of the health benefits and the important contribution of coffee brew to the intake of anti-oxidants in the diet has increased coffee consumption. Chlorogenic acid (ChA) and caffeic acid (CaA) are the major phenolic compounds in coffee. However, phenolic compounds, which are generally effective anti-oxidants, can become pro-oxidants in the presence of Cu²⁺ to induce DNA damage under certain conditions. On the other hand, sodium nitrite (NaNO₂) is widely used as a food additive to preserve and tinge color on cured meat and fish. It is possible that phenolic compounds react with NaNO₂ under acidic conditions, such as gastric juice. In this study, we identified compounds produced by the reaction between ChA or CaA in coffee and NaNO₂ in artificial gastric juice. The identified phenolic compounds and nitrated phenolic compounds were assessed for their anti-oxidant, pro-oxidant, and nitration activities by performing an in vitro assay. The nitrated phenolic compounds seemed to show increased anti-oxidant activity and decreased pro-oxidant activity. However, one nitrated CaA compound that has a furoxan ring showed the ability to release in the neutral condition.     

Changes in Cell Wall-bound Phenolic Compounds and Lignin in Roots of Date Palm Cultivars Differing in Susceptibility to Fusarium oxysporum f. sp. albedinis

The roots of date palm contain four cell wall‐bound phenolic acids identified as p‐hydroxybenzoic, p‐coumaric, ferulic and sinapic acids. The ferulic acid represents the major phenolic compound since it constitutes 48.2–55.8% of cell wall‐bound phenolic acids. All these phenolic acids were present in the resistant cultivar (BSTN) and the susceptible cultivar (JHL). However, the pre‐infection contents of p‐coumaric, ferulic and sinapic acids were greater in the resistant cultivar than in the susceptible one. For the contents of p‐hydroxybenzoic acid, there was no significant difference between the resistant cultivar and the susceptible cultivar. Similarly, the pre‐infection contents of lignin were approximately equal for both cultivars. Inoculation of the date palm roots by Fusarium oxysporum f. sp. albedinis induced important modifications to the contents of the cell wall‐bound phenolic compounds and lignin, which made it possible to distinguish between resistant and susceptible cultivars. The post‐infection contents of cell wall‐bound phenolic compounds underwent a rapid and intense increase with a maximum accumulation on the tenth day for p‐hydroxybenzoic acid (1.54 μmol/g), p‐coumaric acid (2.77 μmol/g) and ferulic acid (2.64 μmol/g) and on the fifteenth day for sinapic acid (1.85 μmol/g). The maximum contents accumulated in the resistant cultivar were greater than those in the susceptible cultivar, namely, 11 times for p‐hydroxybenzoic acid, 2.6 times for p‐coumaric acid, 1.8 times for ferulic acid and 12.3 times for sinapic acid. In the susceptible cultivar, p‐coumaric acid and ferulic acid contents also increased after inoculation although they did not reach the pre‐infection contents of the resistant cultivar. The contents of p‐hydroxybenzoic acid in the susceptible cultivar roots did not present post‐infection modification and those of sinapic acid decreased instead. The lignin contents increased in both cultivars with a maximum accumulation on the fifteenth day. However, the maximum contents accumulated in the resistant cultivar roots were 1.5 times greater than those of the susceptible cultivar. These results showed clear differences between the resistant BSTN and the susceptible JHL cultivars. The implication of cell wall‐bound phenolic compounds and lignin in the resistance of date palm to F. oxysporum f. sp. albedinis appears to be dependent on the speed and intensity of their accumulation with greater contents in the first stage of infection.     

Antibacterial activity of wine phenolic compounds and oenological extracts against potential respiratory pathogens

Aims: To investigate the effect of seven wine phenolic compounds and six oenological phenolic extracts on the growth of pathogenic bacteria associated with respiratory diseases (Pseudomonas aeruginosa, Staphylococcus aureus, Moraxella catarrhalis, Enterococcus faecalis, Streptococcus sp Group F, Streptococcus agalactiae and Streptococcus pneumoniae). Methods and Results: Antimicrobial activity was determined using a microdilution method and quantified as IC₅₀. Mor. catarrhalis was the most susceptible specie to phenolic compounds and extracts. Gallic acid and ethyl gallate were the compounds that showed the greatest antimicrobial activity. Regarding phenolic extracts, GSE (grape seed extract) and GSE‐O (oligomeric‐rich fraction from GSE) were the ones that displayed the strongest antimicrobial effects. Conclusions: Results highlight the antimicrobial properties of wine phenolic compounds and oenological extracts against potential respiratory pathogens. The antimicrobial activity of wine phenolic compounds was influenced by the type of phenolic compounds. Gram‐negative bacteria were more susceptible than Gram‐positive bacteria to the action of phenolic compounds and extracts; however, the effect was species‐dependent. Significance and Impact of Study: The ability to inhibit the growth of respiratory pathogenic bacteria as shown by several wine phenolic compounds and oenological extracts warrants further investigations to explore the use of grape and wine preparations in oral hygiene.     

Fractional changes in phenolic acids composition in root nodules of Arachis hypogaea L.

Phenolic acids are active antimicrobial compounds and root signaling molecules that play important roles in plant defense responses. They are generally present in plants as glycosides or esters. A range of soluble and bound phenolic acids were detected in roots and root nodules of Arachis hypogaea L., among which five were identified by high performance liquid chromatography (HPLC) coupled with UV–Vis diode array detector (DAD), viz., p-coumaric acid (p-com), p-hydroxybenzaldehyde (HBAld), p-hydroxybenzoic acid (HBA), caffeic acid (CA) and protocatechuic acid (PA). Para-coumaric acid was constitutively present in all fractions whereas HBA was present in the soluble form only in young nodules. CA and PA were mostly present in the wall bound fraction. The root nodules contain higher concentration of phenolic acids than non-nodulated roots and presence of peroxidase and polyphenol oxidase indicate the metabolism of phenolic acids in roots and root nodules. These results indicate that phenolic acids (p-com and CA) in bound-glycosidic or ester forms were major components in cell wall fortification which provide protection to the root nodule from pathogen attack.     

Metabolism of phenolic compounds in <Emphasis Type="Italic">Vitis riparia</Emphasis> seeds during stratification and during germination under optimal and low temperature stress conditions

We studied the alterations in phenolic compounds in grape seeds during their stratification and germination under optimal conditions (+25 °C) and at low temperature (+10 °C). Biological materials in the study were seeds of Vitis riparia. Phenolic compounds were extracted from defatted seeds using 80 % methanol or 80 % acetone. The content of total phenolics was determined with the Folin-Ciocalteau reagent, while the content of tannins was determined by vanillin assay and the protein (BSA) precipitation method. The RP-HPLC method was used to determine phenolic compounds (phenolic acids, catechins) in the extracts. High amounts of tannins, catechins, gallic acid and lesser amounts of p-coumaric acid were found in the seeds. The content of total phenolics in acetone extracts was higher than that obtained using methanol. The amounts of phenolic acids and tannins found in V. riparia seeds after stratification were much lower. It may confirm a possible role of these compounds in dormancy of V. riparia seeds. After 72 h of low temperature treatment, inhibition of grape root growth and biochemical changes in seeds were detected. The chilling stimulated increased accumulation of some phenolic compounds (free gallic acid and catechins) in the seeds. These substances can protect plants against some abiotic stressors.     

Contribution of Bioactive Compounds to the Antioxidant Capacity of the Edible Mushroom Neolentinus lepideus

Neolentinus lepideus is a fungus consumed by rural communities in Central America and Asia due to its rich flavor; however, little information on its chemical composition is available. With this in mind, the objective of this work was to determine the content of vitamin E and C, ergosterol, and phenolic compounds of this fungus, as well as its antioxidant capacity. The quantified bioactive compounds were two isoforms of vitamin E, highlighting α-tocopherol (3370.35 mg/100 g dry weight, DW) and ergosterol (11.70 mg/100 g DW). The total phenolic content was 164.80 mg gallic acid equivalents/100 g, and nine phenolic compounds were identified (protocatechuic, p-hydroxybenzoic, caffeic, vanillic, ferulic, salicylic, p-anisic, trans-cinnamic acids, and scopoletin). The highest antioxidant capacity was detected in the lipophilic extract with TEAC (27688 μmoles Trolox equivalents/100 g). These results suggest that lipophilic compounds are among the main bioactive compounds in N. lepideus, and they might exhibit the highest radical scavenging properties in non-polar extracts.     

芦苇腐解土中酚酸类化感物质的水分响应特性研究

芦苇和虉草均具有较强的去污能力,常作为湿地植物配置于同一人工湿地进行污水处理。芦苇作为一种强化感植物对虉草具有较强的化感作用,在自然湿地和人工湿地中均会出现芦苇代替虉草的现象,且这一现象的发生与土壤含水量存在一定联系,此外,芦苇腐解土对虉草的化感抑制效应与腐解土中总酚酸的量密切相关。为了研究芦苇腐解土中主要酚酸类物质的水分响应特性,筛选出其中对水分响应较为明显的酚酸物质种类,该研究采用高效液相色谱法,通过芦苇枯落物腐解土的制备,对不同水分环境下芦苇腐解土中酚酸类物质进行了分离和鉴定。结果表明:芦苇腐解土中可分离出没食子酸、香豆酸、香草酸、丁香酸、对香豆酸、阿魏酸、水杨酸和苯甲酸等8种酚酸类物质,其中香豆酸、苯甲酸和阿魏酸等3种酚酸类物质含量较高。分离出的8种酚酸类物质的含量与腐解土的相对含水量均呈显著线性负相关关系,即随着腐解土相对含水量的上升,酚酸类物质的含量均呈现下降趋势,且各种酚酸类物质对水分的响应趋势均可用线性方程较好地拟合。其中,香豆酸、没食子酸和阿魏酸对芦苇腐解土的水分响应最为明显。因此,可将香豆酸、没食子酸和阿魏酸作为主要调控目标,通过调控湿地土壤中水分含量,削弱芦苇对虉草的化感抑制效应,从而维持人工湿地中虉草芦苇群落的长期稳定共存。