Inhibition of growth ofErwinia carotovora in vitro by phenolics

Summary The phenolic acids caffeic, cinnamic, ferulic, salicylic, sinapic, and vanillic, together with scopoletin and coniferyl alcohol, at concentrations of ≤1 mg/ml, variously inhibited growth ofErwinia carotovora in Nutrient Broth buffered to pH 6 by 0.2 M phosphate buffer. Chlorogenic acid at 1 mg/ml did not inhibit growth but it did so in agar diffusion bioassays at high concentrations (3–10 mg/well) probably by lowering of the pH of the agar.     

市售香蕉 15 种酚酸化合物含量的分析

为了探明香蕉中酚酸化合物的种类及含量,本研究采用超高效液相色谱串联质谱（UPLC-MS/MS）法对 香蕉果肉样品进行分析,并对色谱、质谱条件进行优化。结果表明,香蕉富含多种酚酸化合物,且酚酸化合物主 要以游离酯型和结合型存在。含量较高的 2 种酚酸为异阿魏酸（112.54~370.34 μg/g）、阿魏酸（83.96~157.54 μg/g）。 酚酸含量由高至低依次为异阿魏酸>阿魏酸>对香豆酸>3,5-二羟基苯甲酸>芥子酸>香草酸>咖啡酸>对羟基苯甲 酸>鞣花酸>丁香酸>反式肉桂酸>水杨酸。方法验证结果表明该方法检出限低、线性范围宽、灵敏度高,定量结 果准确、可靠,适用于实际样品检测;香蕉样品酚酸组分与含量检测结果可为香蕉的营养成分和功能活性物质 评价提供参考。     

Chemical composition and profile characterisation of pumpkin (Cucurbita maxima) seed oil

Seeds of a Tunisian variety (Béjaoui) of pumpkin (Cucurbita maxima) were analysed for their main chemical composition and for their oil properties. Expressed on dry weight basis, seed moisture was 8.46%, whereas contents of proteins, fibre, ash, fat, and total sugars established at 33.92%, 3.97%, 21.97%, 31.57%, and 0.11% respectively. Gas chromatography revealed that the major fatty acids were oleic, linoleic, and palmitic acids (44.11%, 34.77%, and 15.97% respectively). Seed oil was also found to be rich in tocopherols with a predominance of δ-tocopherol (42.27%). The sterol marker β-sisosterol accounted for 39.6% of total sterols contained in seed oil of this variety. Six phenolic acids (protocatechuic, caffeic, syringic, vanillic, p-coumaric and ferulic) were detected, the syringic acid being predominant (7.96 mg/100 g). As a whole, based on its seed oil features, pumpkin may be considered as a valuable source for new multi-purpose products for industrial, cosmetic, and pharmaceutical utilisation.     

Accumulation of Polyphenolic Compounds and Osmolytes under Dehydration Stress and Their Implication in Redox Regulation in Four Indigenous Aromatic Rice Cultivars

Present work was undertaken to screen some drought tolerant indigenous aromatic rice cultivars (IARCs), commonly cultivated in West Bengal, India, based on their capacity to produce osmolytes, redox-sensitive phenolic acids and flavonoids, as contrivances for redox-regulation under drought stress. Polyethylene glycol induced post imbibitional dehydration stress mediated changes in redox regulatory properties of the germinating seeds of the four IARCs (Jamainadu, Tulaipanji, Sitabhog, Badshabhog), which were assessed in terms of changes in prooxidant accumulation (in-situ localization of reactive oxygen species (ROS) by confocal microscopy, DCFDA (2′,7′-dichlorofluorescin diacetate) oxidation, O₂⁻ and H₂O₂ accumulation), cumulative antioxidative defense (radical scavenging property and total thiol content), ROS scavenging phenolic acids (gallic acid, protocatechuic acid, gentisic acid, para-hydroxy benzoic acid, chlorogenic acid, caffeic acid, syringic acid, salicylic acid, sinapic acid and p-coumaric acid) and flavonoids (catechin, naringin, rutin, quercetin, kaempferol, myricetin and apigenin). The capability of germinating seeds to accumulate osmolytes (like glycinebetaine, proline, soluble carbohydrates and K⁺ ion) and polyphenolic compounds was also correlated with their corresponding redox status and redox biomarkers (conjugated diene, hydroperoxide, thiobarbituric acid reactive substances and free carbonyl content) produced under the same conditions. The results in general showed that accumulation of osmolytes along with the redox-sensitive phenolics and flavonoids conferred the ability to maintain the redox homeostasis under drought stress for the tolerant IARCs (Badshabhog and Tulaipanji).     

The involvement of phenolics and phytoalexins in resistance of potato to soft rot

Summary Phenolics, for example chlorogenic, caffeic and ferulic acid, and phytoalexins, such as rishitin and phytuberin, were identified in potato tubers cv. Kufri Chandramukhi. The tissue of healthy tubers contained no detectable phytoalexins but did contain phenolics. The levels of these compounds were correlated with soft rot development. The rotting tissue either was free of these groups of compounds or had low concentrations. The wound periderm formed as a result of recovery from injury and infection contained high levels of the compounds. Much higher concentrations were detected at lower storage temperatures when oxygen supply was adequate. Antibacterial properties of the phenolics identified were tested againstErwinia carotovora which was inhibited by chlorogenic, caffeic and ferulic acids. The three phenolics were more effective together, in proportions in which they occurred in wound periderm, than individually. It was observed that none of these phenolics could inhibit pectolytic enzymes ofE. carotovora.     

Phenolic Compounds as Cultivar- and Variety-distinguishing Factors in Some Plant Products

The aim of the study was to determine whether phenolic compounds in some varieties of buckwheat, winter and spring barley and peas can be used as factors which distinguish selected cultivars and varieties of plant material. It was observed that the content of total phenolics might be useful as a cultivar-distinguishing factor for all the plant materials analyzed, but it was a distinguishing factor for only some varieties. Individual cultivars and varieties were best distinguished by the content of syringic acid. The levels of syringic and vanillic acids were in reverse proportion to the total amount of phenolics soluble in methanol and a positive correlation between syringic and ferulic acid was observed. Moreover, the protein content of plant material was analyzed and a significant (p ≤ 0.05) correlation between this component and ferulic and vanillic acids was noted.     

Changes in Phenolic Compounds in Garlic (<Emphasis Type="Italic">Allium sativum</Emphasis> L.) Owing to the Cultivar and Location of Growth

The contents of total phenolic compounds, flavonoids, and phenolic acids were determined in selected garlic cultivars grown at four locations. The total phenolic content varied from 3.4 mg gallic acid equivalents (GAE)/g of dry matter (dm) to 10.8 mg GAE/g of dm with a mean value of 6.5 mg GAE/g of dm. The myricetin, quercetin, kaempferol, and apigenin flavonoids were not detected in any of the samples. Caffeic acid and ferulic acid were the major phenolic acids found with mean values of 2.9 mg/kg of dm and 2.6 mg/kg of dm, respectively. The mean contents of vanillic, p-hydroxybenzoic, and p-coumaric acids were comparable (0.4–0.8 mg/kg of dm), and the level of sinapic acid was negligible (< 0.1 mg/kg of dm). There was a significant effect of location but an insignificant effect of genotype on contents of caffeic, vanillic, p-hydroxybenzoic, and p-coumaric acids. However, genotype but not location affected the contents of total phenolics and ferulic acid. On average, the white garlic cultivars and Chinese garlic cultivars contained higher contents of total phenolics and ferulic acid than the purple garlic cultivars. However, the differences in the total phenolic content between the purple and white garlic cultivars were not significant.     

Variation in Oat Groats Due to Variety, Storage and Heat Treatment. I: Phenolic Compounds

Low molecular weight phenolic compounds present in heat processed oats (Avena sativaL) were analysed. The oat grains were of three varieties (Kapp, Mustang and Svea), stored at different relative humidities (30, 55 or 80%) and periods (3·5 or 15·5 months) and processed with or without hulls. Eleven UV-absorbing compounds detected by High Performance Liquid Chromatography were subjected to univariate and multivariate statistical analysis. The selected compounds included caffeic acid,p-coumaric acid, ferulic acid, vanillic acid,p-hydroxybenzaldehyde, vanillin, coniferyl alcohol, three avenanthramides and one unidentified substance. The levels of vanillic acid, vanillin and, especially,p-coumaric acid,p-hydroxybenzaldehyde and coniferyl alcohol increased significantly in samples processed with hulls, but not in samples processed without hulls. Ferulic acid increased in both processes, while caffeic acid and the avenanthramides were found to decrease during processing. Storage of unprocessed samples for 1 year generally increased the levels of phenolic acids and aldehydes. For the phenolic acids (except ferulic acid), this increase was most pronounced after storage at high relative humidity (80%). The avenanthramides were present at their highest levels in Mustang, caffeic acid in Svea and Mustang, the unidentified compound in Svea, while all the other compounds studied were present predominantly in the variety Kapp.     

A comparative study of phenylpropanoid metabolism in gamma irradiated and unirradiated potato tubers

Summary Phenylpropanoid metabolism in gamma irradiated potato tubers was studied by examining the pattern of incorporation of radioactivity from U-¹⁴C phenylalanine into caffeic acid. chlorogenic acid and the coniferyl and sinapyl moieties of lignin. During a post-irradiation period of 21 days a depletion in chlorogenic acid was observed. This is a result of its impaired synthesis as well as an accelerated conversion of chlorogenic acid to ferulic and sinapic acids and their deposition in lignin. The results offer an explanation for the lower level of chlorogenic acid invariably observed in irradiated potato tubers.     

Polyphenolics Profile, Antioxidant and Radical Scavenging Activity of Leaves and Stem of Raphanus sativus L.

Aerial parts (leaves and stem) of Raphanus sativus, which are usually discarded were found to possess potent antioxidant and radical scavenging activity, as measured by standard antioxidant assays. Methanolic and acetone extracts of R. sativus leaves had total polyphenolic content of 86.16 and 78.77 mg/g dry extract, which were comparable to the traditional rich sources such as green tea and black tea. HPLC identification of polyphenolics indicated the presence of catechin, protocatechuic acid, syringic acid, vanillic acid, ferulic acid, sinapic acid, o-coumaric acid, myricetin, and quercetin in leaves and stem. Among the different extraction solvents, methanolic extract of leaves and stem showed potent reductive capacity, significantly inhibited linoleic acid peroxidation and displayed metal chelating activity. Further, they scavenged free radicals effectively with IC₅₀ (half maximal inhibitory concentration) of 31 and 42 μg/ml for DPPH radical, 23 and 52 μg/ml for superoxide radical, 67 and 197 μg/ml for hydrogen peroxide, and 56 and 62 μg/ml for nitric oxide, respectively. Leaves showed most potent antioxidant and radical scavenging activity as compared to stem, which may be accounted for the high polyphenolic content. Leaves and stem of R. sativus, often under-utilized part of this vegetable, thus possessed considerable amount of polyphenolics. Hence, it should be regarded as a potential source of natural antioxidants and could be effectively employed as an ingredient in health or in functional food.     

Phenolic Compounds in Wheat Grain Cultivars

Three hydroxybenzoic acids: p-hydroxybenzoic acid, vanillic acid and syringic acid; six hydroxycinnamic acids: p-coumaric acid, ferulic acid and four ferulic acid derivatives and a flavonoid (apigenin) were identified and quantified in 34 accessions corresponding to 19 cultivars of wheat applying HPLC coupled to diode array detector. Considerable differences between the wheat cultivars were observed in the phenolic contents. Some cultivars (Colorado, Del País, Barbilla, Jallado, Raspinegro Canario and Plaganudo) could be selected according to the high levels of phenolic compounds. Ferulic acid was the major phenolic acid compound followed by syringic and p-hydroxybenzoic acids. The proportion of ferulic acid present as dimeric forms ranged from 4.2 to 8.6% across all of the wheat cultivars analyzed. Apigenin, p-hydroxybenzoic and syringic acids did not show significant correlations. Many correlations between the determined hydroxycinnamic acids were observed. The ferulic acid and all the ferulic acid derivatives showed highly significant correlations, suggesting that the concentrations of diferulic acids depend on the concentration of ferulic acid.     

Anthocyanins,Phenolic Acids and Antioxidant Properties of Juçara Fruits (Euterpe edulis M.) Along the On-tree Ripening Process

Juçara (Euterpe edulis M.) fruits are an interesting source of phenolic compounds, mainly anthocyanins, making them valuable to the food and pharmaceutical industries. Juçara fruits were harvested along the on-tree ripening process between March and June as practiced in Paraná state, Brazil and examined for their total anthocyanin content (TAC), total phenolic content (TPC), total phenolic acid (TPA) and total antioxidant capacity (TAA). Overall, TAC increased (91.52–236.19 mg cyanidin-3-glucoside equivalent/100 g dm) whereas TPC (81.69–49.09 mg GAE/g dm) and TPA (44.27–30.95 mg/100 g dm) decreased during ripening of juçara fruits. Use of tandem mass spectrometry allowed the identification of cyanidin-3,5-diglucoside, peonidin-3-glucoside and peonidin-3-rutinoside for the first time in juçara fruits. The analysis of the phenolic acids by HPLC-MS/MS indicated the presence of gallic, protocatechuic, p-hydroxybenzoic, vanillic, chlorogenic, caffeic, syringic, p-coumaric, sinapinic and ferulic acids. The high antioxidant capacity using DPPH radical scavenging capacity (655.89–745.32 μmol TE/g dm) and ORAC assays (1088.10–2071.55 μmol TE/g dm) showed that juçara fruits have potential as a source of novel natural antioxidants for disease prevention and health promotion, and also as natural food additives for developing new functional food products.     

Phenolic acids composition,total polyphenols content and antioxidant activity of Triticum monococcum, Triticum turgidum and Triticum aestivum: A two-years evaluation

Wheat is a good source of polyphenols, plant metabolytes with beneficial effects on human health. However, little information is available on phenolic acid composition and concentration in different Triticum species, as well as on possible environmental effects. To shed some light on this issue, thirty-nine wheat accessions cropped for two years and belonging to different Triticum species (Triticum monococcum, Triticum turgidum ssp. dicoccum, turanicum and durum, Triticum aestivum ssp. spelta and aestivum) were assessed for phenolic acids (ferulic, p-coumaric, vanillic, syringic, p-hydroxybenzoic, caffeic acids and syringaldehyde), total polyphenols and antioxidant activity in soluble conjugated and insoluble bound extracts. Ferulic acid was the most abundant compound in both extracts. Insoluble bound phenolic acids represented >90% of total phenolic acids. Einkorn showed the maximum concentration of conjugated phenolic acids (50.5 mg/kg DM), while durum and bread wheats presented the highest content of bound phenolic acids (651.8 and 629.2 mg/kg DM, respectively). Cropping year influenced the concentration of conjugated but not of bound phenolic acids. A survey of phenolic acid distribution in the kernel showed that they are rare in endosperm, but abundant in germ and bran. Total polyphenols and antioxidant activity were highly correlated to phenolic acid content.     

镍处理下水稻酚酸和酚多聚物含量的变化与白叶枯病诱导抗性的关系

 研究了镍处理下水稻叶片中总酚、酚酸、酚多聚物积累和细胞壁结合态过氧化物酶（POD）活性的变化。镍处理导致总酚含量显著上升,检测到10种可溶性酚酸和7种结合态酚酸。镍处理下可溶性绿原酸和水杨酸含量明显上升,而它们的结合态含量变化不明显;镍处理显著提高可溶性和结合态阿魏酸的含量,显著降低可溶性丁香酸和对 香豆酸的含量,却诱导其结合态含量增加。镍处理后酚多聚物明显积累,以阿魏酸和丁香醛为底物的细胞壁结合态POD的活性显著升高。这些结果结合以前的研究提示,酚酸和酚多聚物积累参与了镍诱导的水稻对白叶枯病的抗性。     

The Content of Dietary Fibre and Polyphenols in Morphological Parts of Buckwheat (<Emphasis Type="Italic">Fagopyrum tataricum</Emphasis>)

In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP–UHPLC–ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum.     

玉米秸秆腐解液酚酸物质含量检测及对玉米大斑病菌的影响

通过提取不同时期玉米秸秆腐解液,研究其对玉米大斑病菌菌丝生长和孢子萌发的影响。利用HPLC检测腐解60 d的腐解液,推测其含有对羟基苯甲酸、邻苯二甲酸、香草酸、丁香酸和苯甲酸。通过外源添加法研究酚酸物质对玉米大斑病菌菌丝生长和孢子萌发的影响,结果表明,5种酚酸物质抑制玉米大斑病菌菌丝生长,抑菌率在14.5%~100%,且随浓度的增加抑制作用趋势增强。苯甲酸和邻苯二甲酸在0.125~1 mg/m L浓度下抑制孢子萌发;羟基苯甲酸在0.062 5~1.0 mg/m L浓度下促进孢子萌发。通过田间调查发现,在开始发病时,秸秆还田抑制玉米大斑病病情指数的发展。     

Influence of sprouting and elicitation on phenolic acids profile and antioxidant activity of wheat seedlings

Influence of germination and elicitation on nutraceutical potential of sprouted wheat was investigated. The seeds of three Polish winter wheat cultivars were elicited with 0.1% (w/v) of Saccacharomyces cerevisiae (SC) extract, 0.1% (v/v) Salix daphnoides (SD) bark extract and their combinations (SC/SD 1:1). Seeds were germinated for 4 day at 20 °C in darkness. For phenolic acids determination LC-ESI-MS/MS analysis was used. Antiradical ability, chelating power, reducing power and ability to prevent lipids against oxidation were determined. Bioaccessibility of antioxidative compounds was estimated using in vitro digestion method. Eleven phenolic acids (protocatechuic, p-hydroxybenzoic, vanillic, caffeic, syryngic, p-coumaric, cis- and trans-ferulic, salicylic, trans- and cis-synapinic) were identified. Sprouting increased p-hydroxybenzoic, syryngic and p-coumaric acids level. The most effective elicitor for improving antioxidant activity of potentially bioaccessible phytochemicals was SD. Especially high effect was obtained for antiradical activity, chelating power and ability to lipid prevention.     

Antioxidant,Antimicrobial and Genotoxicity Screening of Hydro-alcoholic Extracts of Five Serbian <Emphasis Type="Italic">Equisetum</Emphasis> Species

The hydro-alcoholic extracts of five Equisetum species, E. arvense L., E. sylvaticum L., E. fluviatile L., E. palustre L. and E. telmateia Ehrh., growing-wild in Serbia were evaluated for their genotoxicity, antimicrobial activity, antioxidant capacity and the results related to the total phenol content and HPLC flavonoid profiles. The total phenol content was 92–349 μmol expressed as equivalents of chlorogenic acid per g of dried plant material. Main identified compounds were kaempferol-, quercetin- glycosides and caffeic acid derivatives. E. telmateia extract showed the greatest antioxidant capacity. Almost all tested microorganisms demonstrated some degree of sensitivity to the examined extracts. All tested extracts at 62.5 μg/ml showed higher incidence of micronucleus formation than in the control sample. The obtained data allowed mutual comparison of examined species and their assessment as possible sources of antioxidants, antimicrobials and/or genotoxic substances.     

Phenolic acid profiles of Chinese wheat cultivars

Phenolic acid concentrations were determined in 37 Chinese commercial winter wheat cultivars grown at a single site over two seasons, and fractions comprising free and bound types were analyzed using HPLC with measurements of individual phenolic acids in each fraction. Most of the parameters were significantly influenced by cultivar, season, and their interaction effects, with cultivar variance being predominant. Wide ranges of concentration among the 37 cultivars were observed. The average concentration of bound type was 661 μg g⁻¹ of dm, making up 97.5% of the phenolic acid determined with ferulic accounting for 70.7% of it, while free type made up only 2.5% of the phenolic acid determined with syringic accounting for 44.7% of it. Bound type was the predominant source to the grain phenolic acid concentrations determined. There were highly significant and positive correlations between bound ferulic concentration and total bound phenolic acid concentration, and between free syringic concentration and total free phenolic acid concentration. Cultivars Liangxing 66 and Zhongmai 895 were stable in concentration of components of phenolic acids across seasons, with high values of free and bound phenolic acids indicating they could be selected as parents in wheat breeding for health beneficial phenolic acid.     

Effect of dietary caffeic and chlorogenic acids on in vivo xenobiotic enzyme systems

The plant phenols chlorogenic and caffeic acids were tested for their affinity to alter hepatic and intestinal xenobiotic Phase I and Phase II enzyme activities in mice. Mice were fed isocaloric and isonitrogenous powdered diets containing 0 and 0.2% caffeic and chlorogenic acids, respectively. Animals pre-treated with benzo(a)pyrene (B(a)P) were sacrificed 18h after an oral dose (50mg/kg Bwt). B(a)P induced animals exhibited higher (p<0.05) microsomal AHH, UDPGT, P-450 and cytosolic GST liver enzyme activities. The presence of these phenolics in the diet was shown to have little effect in modulating hepatic xenobiotic activating-detoxification enzymes. The dietary intake of caffeic and chlorogenic acids was particularly evident with intestinal xenobiotic AHH and GST enzyme activity. These data indicate that the presence of caffeic and chlorogenic acids in the diet may have an integral role in modulating the carcinogenic potential of reactive xenobiotics such as B(a)P.