Levels Of Total Phenolic Acids Research Articles

Phytochemical Analysis of Centaurea calcitrapa L. Aerial Flowering Parts Serial Solvent Extracts and Its Antibacterial and Antioxidant Activities.

To evaluate the phytochemical composition, antibacterial, and antioxidant activity of successive extracts of Centaurea calcitrapa L. (C. calcitrapa) aerial flowering parts, they were assessed in vitro. Using a spectrophotometer, the sample absorbance at 517 nm was used to quantify the scavenging activity. The negative control was DPPH. In the current study, the diffusion using agar wells technique was adapted to measure antimicrobial activity. Phytochemical analysis was performed using the recommended standard procedures. The methanol extract of C. calcitrapa exhibited high levels of total phenolic acids expressed as gallic acid (GA), measured as (97.25 ± 0.73 mg GAE/g) content compared to the chloroform, acetyl acetate, and aqueous extracts (27.42 ± 0.29, 64.25 ± 0.96, and 17.25 ± 0.73 mg GAE/g), respectively. Additionally, the methanol extract had a higher total tannin (27.52 ± 0.53 mg TAE/g) content compared to the chloroform, ethyl acetate, and aqueous extracts (12.02 ± 0.55, 26.01 ± 0.81, and 7.35 ± 0.56 mg TAE/g), respectively, while the aqueous extract contains a lower percentage of flavonoids (141.10 ± 1.31 mg RTE/g) compared to the higher content achieved by the methanol extract (425.93 ± 1.27 mg RTE/g). The hydroxyl groups of the flavonoid and the phenolic compounds found in C. calcitrapa are essentially scavenging free radicals. Radical scavenging activity was highest in the methanol extract (IC50 = 2.82 μg/mL), aqueous extract (IC50 = 8.03 μg/mL), ethyl acetate extract (IC50 = 4.79 μg/mL), and chloroform extract (IC50 = 6.33 μg/mL), as compared to the standard scavenging activity (IC50 = 2.52 μg/mL). The antibacterial properties of C. calcitrapa against Gram-negative bacterial strains Klebsiella pneumoniae, Escherichia coli, Enterobacter aerogenes, and Acinetobacter baumanii, in addition to Gram-positive strains Staphylococcus haemolyticus, Enterococcus faecalis, and Staphylococcus aureus, revealed inhibition zone diameter. The findings of this investigation establish that the aerial flowering parts of C. calcitrapa have substantial antibacterial action against human infections, and the plant can serve as a significant antioxidant that can be employed to prevent and treat severe degenerative diseases brought on by oxidative stress. qPCR showed that C. calcitrapa extracts elevate both SOD1 and SOD2 (cellular oxidation markers) with remarkable folds (1.8-fold for SOD1 and SOD2) with ethyl acetate plant extract against ascorbic acid as a control. This result reflects that C. calcitrapa extracts have remarkable antioxidant activity.

Anticancer potential of acetone extracts from selected Potentilla species against human colorectal cancer cells.

Cinquefoils have been widely used in local folk medicine in Europe and Asia to manage various gastrointestinal inflammations and/or infections, certain forms of cancer, thyroid gland disorders, and wound healing. In the present paper, acetone extracts from aerial parts of selected Potentilla species, namely P. alba (PAL7), P. argentea (PAR7), P. grandiflora (PGR7), P. norvegica (PN7), P. recta (PRE7), and the closely related Drymocalis rupestris (syn. P. rupestris) (PRU7), were analysed for their cytotoxicity and antiproliferative activities against human colon adenocarcinoma cell line LS180 and human colon epithelial cell line CCD841 CoN. Moreover, quantitative assessments of the total polyphenolic (TPC), total tannin (TTC), total proanthocyanidins (TPrC), total flavonoid (TFC), and total phenolic acid (TPAC) were conducted. The analysis of secondary metabolite composition was carried out by LC-PDA-HRMS. The highest TPC and TTC were found in PAR7 (339.72 and 246.92 mg gallic acid equivalents (GAE)/g extract, respectively) and PN7 (332.11 and 252.3 mg GAE/g extract, respectively). The highest TPrC, TFC, and TPAC levels were found for PAL7 (21.28 mg catechin equivalents (CAT)/g extract, 71.85 mg rutin equivalents (RE)/g extract, and 124.18 mg caffeic acid equivalents (CAE)/g extract, respectively). LC-PDA-HRMS analysis revealed the presence of 83 compounds, including brevifolincarboxylic acid, ellagic acid, pedunculagin, agrimoniin, chlorogenic acid, astragalin, and tiliroside. Moreover, the presence of tri-coumaroyl spermidine was demonstrated for the first time in the genus Potentilla. Results of the MTT assay revealed that all tested extracts decreased the viability of both cell lines; however, a markedly stronger effect was observed in the colon cancer cells. The highest selectivity was demonstrated by PAR7, which effectively inhibited the metabolic activity of LS180 cells (IC50 = 38 μg/ml), while at the same time causing the lowest unwanted effects in CCD841 CoN cells (IC50 = 1,134 μg/ml). BrdU assay revealed a significant decrease in DNA synthesis in both examined cell lines in response to all investigated extracts. It should be emphasized that the tested extracts had a stronger effect on colon cancer cells than normal colon cells, and the most significant antiproliferative properties were observed in the case of PAR7 (IC50 LS180 = 174 μg/ml) and PN7 (IC50 LS180 = 169 μg/ml). The results of LDH assay revealed that all tested extracts were not cytotoxic against normal colon epithelial cells, whereas in the cancer cells, all compounds significantly damaged cell membranes, and the observed effect was dose-dependent. The highest cytotoxicity was observed in LS180 cells in response to PAR7, which, in concentrations ranging from 25 to 250 μg/ml, increased LDH release by 110%–1,062%, respectively. Performed studies have revealed that all Potentilla species may be useful sources for anti-colorectal cancer agents; however, additional research is required to prove this definitively.

Reversed-Phase HPLC Characterization and Quantification and Antioxidant Capacity of the Phenolic Acids and Flavonoids Extracted From Eight Varieties of Sorghum Grown in Austria.

Sorghum is raising great interest as a grain for the future, for its agricultural advantages in times of climate change, and for the positive impact of its bioactive compounds on human health. These compounds comprise phenolic acids, in a free, conjugated, and bound form, and flavonoids. The most commonly used extraction methods require high volumes of chemicals and are non-practical when handling many samples at a time. The main aim of this study was to develop a microscale extraction procedure for both phenolic acids and flavonoids to improve yield and diversity, labor time, and chemicals usage. The improved protocols allowed to perform the extraction in 2-ml safe-lock tubes using around 60 times less chemical volume for phenolic acids and 6 times less for flavonoids. In addition, compared to the macroscale method, the microscale approach was effective in extracting a comparable amount of phenolic acids (between 0.99 and 1.57 mg ferulic acid/g) and even a higher quantity of flavonoids (between 1.10 and 2.24 mg ferulic acid/g). With the established methods, phenolic compounds were extracted from eight varieties of sorghum grown in Austria, previously shown to be promising for food processing. In all sorghum varieties, protocatechuic, vanillic, caffeic, syringic, P-coumaric, and ferulic acids were detected in free, conjugated and bound form, with the last being the most abundant. Arsky and Icebergg varieties presented the lowest (922.65 μg/g) and the highest (1,269.28 μg/g) levels of total phenolic acids, respectively, recorded using high-performance liquid chromatography (HPLC). Flavonoids, comprising luteolinidin, apigenidin, naringenin, apigenin, 5-methoxy-luteolinidin (5-MetO-Lut), and 7-methoxy-apigeninidin (7-MetO-Api), were detected in amounts between 27.03 (Kalatur variety) and 87.52 μg/g (Huggo variety). The red varieties, Huggo, Armorik, and Arsky, had the highest antioxidant activity measured as 2,2-Diphenyl-1-picrylhydrazyl (DPPH) [around 5.00 μg Trolox equivalent (TE)/g] and Azino-bis(3-ehtylbenzthiazoline-6-sulfonic acid) (ABTS) (around 3.00 μg TE/g) scavenging capacity for both phenolic acids and flavonoids. Ferric reducing antioxidant power (FRAP) was the highest for the phenolic acids extracted from a white Ggolden variety.

Accumulation of Phenolic Acids during Storage over Differently Handled Fresh Carrots.

Carrots contain a significant content of phenolic compounds, mainly phenolic acids. Technological processing of carrots inflicts wounding stress and induces accumulation of these compounds, especially caffeic acid derivatives, in the periderm tissue. In this study, the effect of minimal processing (polishing, washing, peeling, and grating) on the retention of soluble phenolic acids in carrots was monitored during cold storage. Storage for up to 4 weeks and 24 h was used for whole and grated carrot samples, respectively. Total phenolic acid levels found in differently processed carrots varied greatly at the beginning of the storage period and on dry weight basis they ranged from 228 ± 67.9 mg/kg (grated carrot) to 996 ± 177 mg/kg (machine washed). In each case, processing followed by storage induced phenolic acid accumulation in the carrots. At the end of the experiment (4 weeks at +8 °C), untreated and machine-washed carrots contained ca. 4-fold more phenolic acids than at day 0. Similarly, polished carrots contained 9-fold and peeled carrots 31-fold more phenolic acids than at day 0. The phenolic acid content in grated carrot doubled after 24 h storage at +4 °C. Individual phenolic acids were characterized by high resolution mass spectrometry. MS data strongly suggest the presence of daucic acid conjugates of phenolic acids in carrot. Storage time did not have statistically similar effect on all compounds and generally in a way that dicaffeoyldaucic acid had the highest increase. This research provides important information for primary production, packaging, catering, the fresh-cut industry and consumers regarding the selection of healthier minimally processed carrots.

Antioxidant properties and hepatoprotective effect of the edible halophyte Crithmum maritimum L. against carbon tetrachloride-induced liver injury in rats

A number of studies have shown the importance of halophyte species as sources of natural antioxidants. Crithmum maritimum is considered an edible and medicinal plant, though in vivo studies of this plant still are necessary to elucidate its potential benefits in alleviating toxicity. The present work was undertaken to investigate the major components and the antioxidant profile of C. maritimum leaf hydro-methanolic extract (CME) and the protective effects of C. maritimum (CM) against CCl4-induced toxicity in rats. Using LC–ESI–MS analysis, 17 phenolic compounds were identified in plant extract, with chlorogenic acid being the major component. The levels of total phenolic acids, total flavonoids and flavonols were ca. 26 mg GAE/g DW, 15.6 mg CE/g DW and 12 mg QE/g DW, respectively. Accordingly, CME showed important in vitro antioxidant activities (DPPH and ORAC). Moreover, CM supplementation to CCl4-intoxicated rats partially restored the impaired hepatic markers (ALT and AST activities and creatinine level), and reduced the CCl4-induced oxidative stress as shown by lipid peroxidation, GSH and protein carbonyl levels. The drug metabolizing system was also evaluated in liver by the measurement of some cytochrome P450-dependent activities such as ECOD, EROD and pNPH and the antioxidant DT-diaphorase, CAT and heme oxygenase activities. Thus, CM treatment reduced the enzymatic perturbations induced by CCl4 and hepatic damages observed from histopathological examination. The obtained results highlight the potential interest of C. maritimum as a source of bioactive compounds with relevant hepatoprotective effects.

Identification/quantification of free and bound phenolic acids in peel and pulp of apples (Malus domestica) using high resolution mass spectrometry (HRMS)

Free and bound phenolic acids were measured in the pulp and peel of four varieties of apples using high resolution mass spectrometry. Twenty-five phenolic acids were identified and included: 8 hydroxybenzoic acids, 11 hydroxycinnamic acids, 5 hydroxyphenylacetic acids, and 1 hydoxyphenylpropanoic acid. Several phenolics are tentatively identified for the first time in apples and include: methyl gallate, ethyl gallate, hydroxy phenyl acetic acid, three phenylacetic acid isomers, 3-(4-hydroxyphenyl)propionic acid, and homoveratric acid. With exception of chlorogenic and caffeic acid, most phenolic acids were quantified for the first time in apples. Significant varietal differences (p<0.05) were observed in both peel and pulp. The levels of total phenolic acids were higher in the pulp as compared to apple peel (dry weight) in all varieties. Coumaroylquinic, protocatechuic, 4-hydroxybenzoic, vanillic and t-ferulic acids were present in free forms. With exception of chlorogenic acid, all other phenolic acids were present only as bound forms.

Effects of cultivar and harvest time on the contents of antioxidant phytochemicals in strawberry fruits

The effects of cultivar and harvest time on the yield, amount of soluble solids, and antioxidant content of five strawberry (Fragaria × ananassa Duch.) genotypes were investigated. The three cultivars and two breeding selections were cultivated in a greenhouse. The yields of the five genotypes were compared, and contents of total anthocyanins, total phenolic acids, soluble sugars and organic acids were analyzed from February to May 2014. The breeding selection San × Aki 2 produced the highest yield. Total amounts of anthocyanins, sucrose, glucose, and fructose were greatest in February and slowly decreased subsequently. Total amounts of phenolic and organic acids varied depending on the month of observation for all cultivars and selections. Total anthocyanin content was the highest in ‘Seolhyang’ strawberry fruits in February and in the breeding selection San × Seol 13 from March to May. The breeding selection San × Aki 2 showed notably high total phenolic acid levels. Soluble sugars decreased over time, with the highest sucrose content found in ‘Seolhyang’, the highest glucose content in ‘Santa’, and the highest fructose content in San × Aki 2. The highest citric acid content was found in ‘Santa’, and the highest malic acid content in San × Seol 13. The sugar/acid ratio was highest in ‘Seolhyang’ and gradually declined over time. The breeder selections San × Aki 2 and San × Seol 13 showed particular promise for their high yields and high concentrations of antioxidant phytochemicals.

Impact of boron, calcium and genetic factors on vitamin C, carotenoids, phenolic acids, anthocyanins and antioxidant capacity of carrots (Daucus carota)

Carrots (Daucus carota L.) were used to investigate the effects and interactions of cultivar and mineral supply on the nutritional quality (antioxidant potential, vitamin C, carotenoids and phenolic acids) of the resulting storage roots. The supplement of boron (B) and or calcium (Ca) in the feeding solutions, during plant growth, influenced the accumulation of other minerals, such as P, K, Mg, S and Na, in the storage roots (p<0.05). When no additional B or Ca was supplied (e.g. −B or −Ca treatment), we observed 33–50% increase in the accumulated levels of α- and β-carotenes, and 45–70% increase of vitamin C. Carrots grown with no supplement of B in the nutrient solutions (e.g. −B treatment and −ve control) had significantly higher (p<0.001) levels of total phenolic acids compared to the carrots with the supplement of B (e.g. −Ca treatment and +ve control). A strong positive correlation was observed between the total phenolic contents and ORAC values (r=0.932) in all the cultivars. The results suggest that both cultivar and mineral supply were major determinants of nutritional quality of the carrots. The nutritional value of carrot crops (with an acceptable physical quality) can be enhanced by manipulating mineral nutrient applications.

Protective effects of an aqueous extract from pepino (Solanum muricatumAit.) in diabetic mice

This study analysed the content of ascorbic acid, phenolic acids and flavonoids in aqueous and ethanol extracts of pepino (Solanum muricatum Ait.), and examined the protective effects of pepino aqueous extract (PAE) in a mouse model of diabetes. PAE at 1, 2 and 4% was supplied for 5 weeks. Aqueous and ethanol extracts had similar levels of total phenolic acids, but PAE had a higher content of ascorbic acid and total flavonoids than the ethanol extract. PAE treatments at 2% and 4% significantly lowered plasma glucose level (P < 0.05); however, only the 4% PAE significantly elevated plasma insulin level at week 5 (P < 0.05). PAE treatments significantly decreased the levels of malonyldialdehyde and reactive oxygen species in kidney (P < 0.05); however, only the 2% and 4% treatments significantly reduced oxidised glutathione formation, increased glutathione level, and retained renal glutathione peroxidase and catalase activities (P < 0.05). PAE treatments at 2% and 4% significantly lowered renal interleukin (IL)-6 and tumour necrosis factor-α levels (P < 0.05); however, only the 4% treatments significantly diminished renal IL-1β and levels of monocyte chemoattractant protein-1 (P < 0.05). PAE treatments at 4% significantly decreased aldose reductase activity and sorbitol production in kidney (P < 0.05). These findings support the suggestion that pepino aqueous extract could attenuate the progression of diabetes via its antioxidative, anti-inflammatory and antiglycative effects.

Effects of Environment and Genotype on Phenolic Acids in Wheat in the HEALTHGRAIN Diversity Screen

Phenolic acid content and composition have been determined in 26 wheat genotypes grown in Hungary over three consecutive years and at three additional locations (France, United Kingdom, and Poland) during the third year. Fractions comprising free, soluble conjugated, and bound phenolic acids were analyzed using HPLC with measurements being made for individual phenolic acids in each fraction. Statistically significant differences in phenolic acid content occurred across the different growing locations with the average total phenolic acid content being highest in the genotypes grown in Hungary. The growth year in Hungary also had a large impact, especially on the free and conjugated phenolic acid contents. Certain genotypes were more resistant to environmental impacts than others. Of the genotypes with high levels of total phenolic acids, Lynx, Riband, Tommi, and Cadenza were most stable with respect to their total contents, whereas Valoris, Herzog, and Malacca, also high in phenolic acid content, were least stable. Of the three fractions analyzed, the free and conjugated phenolic acids were most variable and were also susceptible to the effect of environment, whereas bound phenolic acids, which comprised the greatest proportion of the total phenolic acids, were the most stable.

The effect of silicon on the symptoms of manganese toxicity in maize plants

The effect of exogenously applied silicon (Si) on plant growth, lipid peroxidation, total phenolic compounds and non-protein thiols was studied in two maize varieties (Zea mays L. vars. Kneja 605, 434) differing in sensitivity to excess manganese (Mn). Based on the density of brown spots per leaf area and relative shoot weight (RSW) used to define Mn tolerance var. Kneja 434 was found to be more Mn-tolerant than Kneja 605. The lipid peroxidation level and total phenolic compounds were enhanced with increasing Mn concentration in the nutrient solution. In addition, the Mn-sensitive var. Kneja 605 with markedly expressed first visible Mn toxicity symptoms had higher levels of total phenolic acids than var. Kneja 434 thus supporting the hypothesis that a stimulating effect of Mn on phenol content reflected rather a stress response to Mn excess than a tolerance mechanism. In contrast, non-protein SH content increased to a higher extent in the Mn-tolerant var. Kneja 434. The increased amount of non-protein SH compounds was accompanied by a much stronger oxidative stress in the Mn-sensitive plants when compared with the Mn-tolerant variety, thus suggesting that non-protein SH compounds may play a role in Mn tolerance in maize. The addition of silicon (Si) reduced the density of brown spots per leaf area as well as lipid peroxidation level and improved plant growth in Mn-treated plants.

Analysis of Phenolic Compounds by High-Performance Liquid Chromatography and Liquid Chromatography/Mass Spectrometry in Potato Plant Flowers, Leaves, Stems, and Tubers and in Home-Processed Potatoes

Potato plants synthesize phenolic compounds as protection against bruising and injury from bacteria, fungi, viruses, and insects. Because antioxidative phenolic compounds are also reported to participate in enzymatic browning reactions and to exhibit health-promoting effects in humans, a need exists for accurate methods to measure their content in fresh and processed potatoes. To contribute to our knowledge about the levels of phenolic compounds in potatoes, we validated and used high-performance liquid chromatography and liquid chromatography/mass spectrometry to measure levels of chlorogenic acid, a chlorogenic isomer, and caffeic acid in flowers, leaves, stems, and tubers of the potato plant and in home-processed potatoes. The total phenolic acid content of flowers (626 mg/100 g fresh wt) was 21 and 59 times greater than that of leaves and stems, respectively. For all samples, chlorogenic acid and its isomer contributed 96-98% to the total. Total phenolic acid levels (in g/100 g fresh wt) of peels of five potato varieties grown in Korea ranged from 6.5 to 42.1 and of the flesh (pulp) from 0.5 to 16.5, with peel/pulp ratios ranging from 2.6 to 21.1. The total phenolic acid content for 25 American potatoes ranged from 1.0 to 172. The highest amounts were present in red and purple potatoes. Home processing of pulp with various forms of heat induced reductions in the phenolic content. The described methodology should facilitate future studies on the role of potato phenolic compounds in the plant and the diet.

Heat stress reduces the accumulation of rosmarinic acid and the total antioxidant capacity in spearmint (Mentha spicata L)

AbstractSelected high‐phenolic lines of spearmint were subjected to a constant 30 °C heat regimen for a period of 4 weeks to determine the effects of heat stress on soluble phenolics, phenols and rosmarinic acid biosynthesis and antioxidant capacity. Heat stress significantly reduced levels of total phenolic acids (71–87%) and soluble phenols (75–87%). This loss was concomitant with a loss of total antioxidant capacity of 21–60% after week 1 and up to 95% by week 4. High‐performance liquid chromatography profiling of heat‐stressed plants at 270 and 320 nm detected nearly a complete loss of rosmarinic acid in all seven chemotypes. High‐temperature drying of non‐heat‐stressed plants at 80 °C resulted in a similar loss of total antioxidant capacity and rosmarinic acid content an effect not observed in material that was subjected to low‐temperature drying first, followed by exposure to high temperature. This suggests that heat stress negatively regulates rosmarinic acid biosynthesis and causes a potential rapid biological breakdown of rosmarinic acid in tissues. 2,2‐Diphenyl‐1‐picrylhydrazyl radical assays of heat‐stressed and non‐stressed plants clearly show that rosmarinic acid is the major contributor to the antioxidant capacity in spearmint. Copyright © 2005 Society of Chemical Industry

Phenolic acid and condensed tannin concentrations of six cotton genotypes

Phenolic acids and condensed tannins have been implicated in plant resistance to insects and diseases. The objective of this study was to determine phenolic acid and condensed tannin concentrations in six cotton ( Gossypium hirsutum L.) genotypes that display varying degrees of spider mite [ Tetranychus urticae (Koch)] resistance. Since phenolic acids are precursors for condensed tannins in the shikimate pathway, the levels of these compounds should be positively correlated. Leaf blades from whole cotton plants grown in a controlled environment were analyzed using HPLC techniques at two growth stages (pinhead-square and first-bloom) for concentrations of 13 tentatively identified phenolic acids, while condensed tannin concentrations were determined spectrophotometrically from extracts of the topmost unfolded leaf and the fourth mainstem leaf from the terminal. Caffeic, p-coumaric and salicylic acids occurred at high concentrations relative to the other phenolic acids. Gallic, gentisic, protocatechuic, benzoic and ferulic acids occurred at intermediate concentrations; p-hydroxybenzoic, vanillic, syringic, sinapic and cinnamic acids occurred at low concentrations. Genotypes that exhibited higher levels of condensed tannins also had significantly higher levels of total phenolic acids, syringic acid and p-coumaric acid concentrations. Additionally caffeic, p-hydroxybenzoic, syringic, p-coumaric and benzoic acids and total phenolic acids were highly correlated with condensed tannin concentrations. Phenolic acid concentrations decreased, while condensed tannin concentrations increased, from pinhead-square to first-bloom growth stages in all genotypes. While genotypes displaying some degree of resistance to the spider mite may have been selected for elevated condensed tannin levels, these genotypes also may have been inadvertently selected for high phenolic acid levels. Therefore, the observed resistance in these genotypes may be attributed to high levels of not only condensed tannins, but also phenolic acids.

Phenolic compounds in different sorghum tissues during maturation

Sorghum bicolor (L.) Moench contains phenolic compounds which vary according to growth stage and plant tissue. Caryopses, glumes, stalks, and leaves of AT × 623 ∗ CS3541 were sampled from 0 do t0 days after anthesis (DAA) and analyzed for free phenolic compounds (FPC) using the Folin-Ciocalteu method and total phenolic acids (TPA) using high performance liquid chromatography. Average levels of FPC were 0·5 (caryopses), 2·2 (glumes), 0·9 (stalks), and 6·2 mg g −1 (leaves). Caryopses and glumes had higher FPC levels 15 DAA; FPC levels within stalks did not change during maturity; young, lower leaves had higher FPC levels. Average levels of TPA were 2·5 (caryopses), 10·6 (glumes), 4·8 (stalks), and 7·6 mg g −1 (leaves). Caryopses and stalks contained stable levels of TPA during maturation. Glumes contained maximum levels of TPA at physiological maturity of caryopsis (27 DAA) while young, upper leaves contained more TPA. The most abundant phenolic acids, p-coumaric, salicyclic, and ferulic acids, were present at 0·2–2·0 mg g −1. These levels of FPC and phenolic acids are inhibitory to many microbes and enzymes involved with digestion of biomass in the rumen of livestock and in biomass-fuel systems.