Wyniki wyszukiwania - AGRO

1

Phenolic acids in leaves and roots from Jovibarba sobolifera [SIMS.] Opiz

100%

Szewczyk K., Krzaczek T.

Herba Polonica

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2004

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tom 50

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nr 3-4

Phenolic acids from leaves and roots ofJovibarba sobolifera (Sims.) Opiz were analysed by means of the two-dimensional thin layer chromatography and by the RP-HPLC method. Twelve phenolic acids were identified by 2D-TLC: chlorogenic, gallic, protocatechuic, caffeic, p-coumaric, p-hydroxy- benzoic, p-hydroxyphenylacetic, vanillic, syringic, ferulic, synapic and a-rezorcylic. The RP-HPLC enabled describing the contents often major phenolic acids in the examined material.

2

Phenolic acids in leaves of species of the Aquilegia L. genus

100%

Szaufer-Hajdrych M.

Herba Polonica

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2004

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tom 50

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nr 2

The contents of phenolic acids in the leaf extracts of ten Aquilegia L. species (A. vulgaris L., A. alpina L.,/4- atrata Koch., A. canadensis l.,A. caerulea James, A. flabellata Sieb, et Zucc., A. hybrida Scott- Elliot, A. olympica Boiss., A. pyreneica D.C., A. vitoleili L.) were determined by the spectroscopic methods and expressed as caffeic acid equivalent. The obtained results ranged from 0.31% to 1.13%. The qualitative analysis was performed by 1D- and 2D-TLC chromatography against the standards. In all studied samples the following acids were found: p-hydroxybenzoic, vanillic, protocatechuic, p-coumaric, caffeic, ferulic, and chlorogenic. Moreover, in some extracts sinapic, gallic, a- and y-resorcylic acids were detected.

3

Phenolic acids from the herb of Linaria vulgaris [L.] Mill.

100%

Sokolowska-Wozniak A., Szewczyk K., Nowak R.

Herba Polonica

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2003

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tom 49

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nr 3-4

Phenolic acids from herb of Linaria vulgaris (L.) Mill, were analysed by means of two dimensional thin layer chromatography and RP-HPLC method. Ten acids were identified: protocatechuic, gallic, caffeic, p-hydroxybenzoic, p-coumaric, vanillic, ferulic, homoprotocatechuic, salicylic and o-hydroxyphenylacetic. By the RP-HPLC method the content of five major compounds in fraction of free phenolic acids was determined.

4

Effect of hydrothermal processing on phenolic acids and flavonols contents in selected Brassica vegetables

88%

Sikora E., Cieslik E., Filipiak-Florkiewicz A., Leszczynska T.

Acta Scientiarum Polonorum. Technologia Alimentaria

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2012

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tom 11

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nr 1

Background. Commonly occurring diseases can have the origin in oxidative processes ongoing in the human body. Vegetables of Brassicaceae family are the essential sources of natural antioxidants, especially phenolic compounds, in the human diet. The research was aimed to estimate the content of phenolic compounds in selected vegetables and their quantity changes during hydrothermal processes. Material and methods. The vegetables subjected to analysis were: kale, broccoli, Brussels sprouts, and white and green cauliflower. The fresh and processed (blanched, cooked, frozen, cooked after freezing) vegetables were freeze-dried. The levels of phenolic acids and flavonols by HPLC method were estimated. Results. The presence of derivatives of hydroxycinnamic acid, mainly of caffeic acid, p-coumaric acid, sinapic acid and of flavonols - kaempferol, and in smaller amounts of quercetin was found. The largest amounts of above components were present in kale (total 94.4 mg-100 g'1 of fresh matter), whereas the smallest amounts were found in white and green cauliflower - 3.6 mg-100 g’1 f.m. and 3.03 mg-100 g'1 f.m., respectively. The applied technological processes contributed to lover amounts of all tested compounds depending on the process and the vegetable kind. The biggest loses, up to 70-80%, took place during cooking of raw and previously frozen vegetables. Conclusions. Analysed Brassicaceae were characterized by high contents of the investigated flavonoids. The best source of those compounds was kale whereas the smallest amounts of searched components were presented in cauliflowers. The used hydrothermal processes led to losses of searched compounds.

5

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Synergistic antibacterial effect of phenolic acids against Escherichia coli

88%

Synowiec A., Zyla K., Gniewosz M.

Zeszyty Problemowe Postępów Nauk Rolniczych

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2019

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tom 598

6

A rapid HPLC method for determination of major phenolic acids in plant material

88%

Olkowski A. A., Amarowicz R., Peiquiang Y., McKinnon J. J., Maenz D. D.

Polish Journal of Food and Nutrition Sciences

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2003

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tom 12/53

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nr 1

The present work describes a simplified, and rapid HPLC method for measurement of phenolic acids in plant material. This procedure allows baseline resolution of major phenolic acids commonly found in plants p-hydroxybenzoic, caffeic, syringic, o-coumaric, m-coumaric, p-coumaric, gentisic, ferulic, sinapic, salicylic), it is specific, sensitive, and ensures good reproducibility. The precision and reproducibility obtained using the present approach gave results comparable or better than the more complex, more laborious, and time consuming procedures. The time of HPLC separation of the phenolic acids in the presented procedure was significantly improved by the use of polymer based reverse phase column (PRP-1 column; 4.1 x 150 mm, 5 /µm; Hamilton), and careful attention to the pH of the mobile phase, which allowed turnaround times of approximately 15 min and significantly lower solvent use. The present method allows the possibility for processing of a large number of samples rapidly, efficiently, and at a low cost.

7

Quantitative determination of the bacteriostatic activity against Staphylococcus aureus of certain flavonoids, phenolic acids and esters occurring in propolis

88%

Maciejewicz W., Meresta T.

Bulletin of the Veterinary Institute in Puławy

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1999

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tom 43

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nr 1

Bacteriostatic activity against Staphylococcus aureus of eleven single flavonoids, pinostrobin chalcone, cinnamic acid and four of its derivatives, hydrocinnamic acid, benzoic acid and six of its derivatives and vanillin occurring in propolis has been determined quantitatively by the method of serial dilutions. Moreover, the determination of bacteriostatic activity has been performed using ethanolic extract of propolis as well as that of three fractions obtained separately from propolis and identified earlier by GC-MS method. These were the following fractions: 1) the water fraction, 2) the fraction volatile with water vapour, 3) the flavonoids fraction. Bacteriostatic activities were also established for four flavonoids and eight organic acids using BIO method and the results of the used methods are compared and discussed. The highest bacteriostatic activity against Staphylococcus aureus displayed the following flavonoids: kaempferid, galangin, apigenin, quercetin, rhamnetin, pinocembrin and kaempherol.

8

Grapevine leaves as a source of natural antioxidants

88%

Amarowicz R., Narolewska O., Karamac M., Kosinska A., Weidner S.

Polish Journal of Food and Nutrition Sciences

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2008

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tom 58

|

nr 1

The crude extracts of phenolic compounds were obtained from grapevine leaves using 80% acetone and 80% methanol (v/v). The content of total phenolic and condensed tannins was determined using Folin & Ciocalteau’s phenol reagent, vanillin/HCl reagent, and protein precipitation method. The antioxidant properties of the extracts were investigated using the total antioxidant activity (TAA), DPPH radical scavenging activity and reducing power. The content of individual phenolic acids was determined using the HPLC method. The content of total phenolics in grapevine leaves and their extracts determined in this study was high (257 mg/g acetone extract and 232 mg/g methanolic extract). The content of condensed tannins in acetone extract was higher than in the methanolic one. Antiradical activity of both extracts against DPPH radical and reducing power were similar and strong. The acetone and methanolic extracts exhibited TAA of 1.37 and 1.44 mmol Trolox/g, respectively. Vitis vinifera leaves extracts were observed to contain gallic, caffeic, and p-coumaric acid. Gallic acid was a dominant phenolic acid. The majority of phenolic acids were found in the form of esters.

9

The influence of plant mulches on the content of phenolic compounds in soil and primary weed infestation of maize

75%

Stoklosa A., Hura T., Stupnicka-Rodzynkiewicz E., Dabkowska T., Lepiarczyk A.

Acta Agrobotanica

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2008

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tom 61

|

nr 2

In growing maize, an increase in the content of phenolic compounds and selected phenolic acids in soil was found after the incorporation of white mustard, buckwheat, spring barley, oats and rye mulches into the soil. The highest content of phenolic compounds in soil was found after oats mulch incorporation (20% more than in the control soil). The highest content of selected phenolic acids was found for the soil with the oats and rye mulch. Among the phenolic acids investigated, ferulic acid was most commonly found in the soil with the plant mulches. However, two phenolic acids: the protocatechuic and chlorogenic acid, were not detected in any soil samples (neither in the control soil nor in the mulched soil). At the same time, a decrease in the primary weed infestation level in maize was found in the plots with all the applied plant mulches, especially on the plots with oats, barley and mustard. The plant mulches were more inhibitory against monocotyledonous weeds than dicotyledonous ones. During high precipitation events and wet weather, a rapid decrease in the content of phenolic compounds in soil and an increase in the primary weed infestation level in maize were observed.

10

Phenolic, carotenoid, ascorbic acid contents and their antioxidant activities in bell pepper

75%

Akhtar M., Ahmad A., Masud T., Wattoo F. H.

Acta Scientiarum Polonorum. Hortorum Cultus

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2019

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tom 18

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nr 1

Essential nutritional components are quantified in the study in addition to major antioxidants, carotenoids, phenols and flavonoids. Their antioxidant activities were also analyzed using DPPH, ABTS and hydrogen peroxide radical scavenging activities and by determining their iron reducing power. Results indicated that the highest quantity of nutritional and antioxidant components was obtained in red variety (4.63 mg/g ascorbic acid, 10.32 mg/g total carotenoid content, 61.50 mg/g total flavonoid content, 310.27 mg/g total phenolic content) followed by orange, yellow and green varieties. Similar trend was observed while analyzing their antioxidant activities by different methods. In studying correlation between components and antioxidant activity, a strong correlation was obtained for ABTS radical scavenging activity with total phenolic content (R2 = 0.722) and total carotenoid contents (R2 = 0.709), while moderate correlation was observed for ABTS radical scavenging activity with total flavonoid contents (R2 = 0.517) and ascorbic acid (R2 = 0.673).

11

Ellagic acid content in fruits of selected strawberry cultivars

75%

Bojarska J. E., Zadernowski R., Czaplicki S.

Polish Journal of Natural Sciences

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2011

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tom 26

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nr 2

Ellagic acid is a biologically active compound, regarded as preventive against various diseases and demonstrates anticarcinogenic and antioxidant effects. In Poland, one of the five largest strawberry producers, the supply of these fruits is significant; therefore exploration of this subject and dissemination of the knowledge concerning their nutritional values and health-related properties is important. The aim of the study was to determine the content of ellagic acid in the most popular, selected strawberry cultivars in Poland. Fruits of the strawberry cultivars under examination differed significantly in ellagic acid content. The content of the analysed component ranged from 452.5 mg kg⁻¹ fresh weight (4,575.6 mg kg⁻¹ dry matter) in fruits of the ‘Heros’ cultivar to 1,193.8 mg kg⁻¹ fresh weight (14,215.0 mg kg⁻¹ d.m.) in fruits of the ‘Camarosa’ cultivar. The highly diversified content of ellagic acid in fruits of individual cultivars, grown in similar soil and weather conditions and subjected to the same agricultural treatments, indicates that the content of the analysed phenolic acid depends not only on the fruit species, but also on the cultivar.

12

Phenolic acids of walnut (Juglans regia L.)

75%

Chrzanowski G., Leszczynski B., Czerniewicz P., Sytykiewicz H., Matok H., Krzyzanowski R.

Herba Polonica

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2011

|

tom 57

|

nr 2

The chromatographic separations showed the presence of eleven free phenolic acids (trans-cinnamic, o-coumaric, p-coumaric, chlorogenic, ferulic, gallic, caffeic, p-hydroxybenzoic, syringic, tannic and vanillic) in the walnut tissues. The p-hydroxybenzoic acid was a predominant compound in the green husks (618.8 µg·g-1), though, high content of it was found in leaves obtained in July (478.3 µg·g-1). The content of chlorogenic acid in green husks of walnut (306.7 µg·g-1) was twice higher than that in the leaves obtained in July. Similar level of coumaric acids was determined in the leaves and green husks (o-coumaric: 42.4–48.2 µg·g-1; p-coumaric: 78.6–94.3 µg·g-1), though, o-coumaric acid was not found in May-leaves. Moreover, leaves of walnut possessed high content of caffeic acid (leaves obtained in May – 456.9; leaves obtained in July – 262.1 µg·g-1) and ferulic acid (leaves obtained in May – 93.5; leaves obtained in July – 292.5 µg·g-1). The predominant compound of the male inflorescences was vanillic acid (359.5 µg·g-1). The green husks of walnut were rich in polyphenolic acids, syringic (427.0 µg·g-1) and tannic (237.4 µg·g-1). However, the content of tannic acid was higher in the leaves - especially in leaves collected in May (350.7 µg·g-1). In tested tissues of walnut, gallic acid was found in the lowest concentration (male inflorescences – 32.7 µg·g-1and leaves obtained in July – 12.7 µg·g-1). In general, there was a great variation in a level of the phenolic acids between the studied organs of the walnut; nevertheless, walnut tissues are precious source of phenolic acids.

13

Comparison of antioxidant properties of selected long-chain alkyl esters of phenolic acids as potential cosmetic components

75%

Kiewlicz J., Szymusiak H.

Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze

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2015

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nr 4

14

Changes in reducing activity of reductones and phenolic acids during reactions with reactive carbonyl compounds

75%

Konecny M., Subrtova M., Cejpek K., Velisek J.

Polish Journal of Food and Nutrition Sciences

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2011

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tom 61

|

nr Suppl.1

15

Phenolic acids in extracts obtained from the flowering herbs of Cirsium vulgare (Savi) Ten. growing in Poland

75%

Kozyra M., Glowniak K.

Acta Societatis Botanicorum Poloniae

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2013

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tom 82

|

nr 4

In this work the phenolic acids in the methanol extract from the flowering herbs of Cirsium vulgare (Savi) Ten. growing in Poland were isolated and identified. The samples containing free phenolic acids and those released after acid and alkaline hydrolyses were investigated by 2D TLC on cellulose. After purification by SPE, samples were also analyzed by RP-HPLC. Six phenolic acids such as gallic, protokatechuic, gentisic, hydrobenzoic, vanillic and caffeic acids were detected in the fraction of free phenolic acids of the methanol extract, irrespectively of the method used.

16

Effects of elicitation on the production of phenolic acids in cell culture of Ginkgo biloba L.

75%

Szewczyk A.

Acta Physiologiae Plantarum

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2007

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tom 29

|

nr 1 Suppl.

17

The impact of extrusion on the content of polyphenols and antioxidant activity of rye grains [Secale cereale L.]

75%

Gumul D., Korus J., Czechowska K., Barton H., Folta M.

Acta Scientiarum Polonorum. Technologia Alimentaria

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2010

|

tom 09

|

nr 3

319-330

Background. Polyphenols which are included in a group of food antioxidants have a beneficial impact on human organism, as they prevent the occurrence of life style diseases, including cardiovascular diseases and cancer. Cereals are the main source of polyphenols in a human diet, and especially rye is characterized by high level of these compounds. Many technological processes applied in food production cause a decrease of polyphenols in rye and reduce their antioxidative activity. The aim of the study was to estimate quantitative changes of polyphenols in rye grains subjected to extrusion, under varying process conditions and establish the antioxidant activity of the obtained rye extrudates. Material and methods. The materials were extrudates prepared from grains of three rye cultivars, namely Amilo, Rostockie and Agrikolo. Extrusion was performed in a single- screw laboratory extruder Brabender 20 DN. Contents of phenolic acids and apigenin in analysed samples was checked by HPLC. Antioxidant activity was measured by FRAP and EPR methods. Results. All rye extrudates contained ferulic acid levels (53-104 mg/100 g d.m.) approximately 112-316% higher as compared to raw material (25 mg/100 g d.m.). The highest antioxidant activity (using of FRAP method) was measured in extrudates prepared at extrusion parameters: 14% moisture of raw material and 180°C but the lowest at 20% moisture and 120°C. The analysis of spin label reduction kinetics (in EPR method) allowed to conclude, that its reduction was greater for extrudates (except extrudates obtained at moisture content 20% and 120°C) as compared to raw material. Conclusions. Content of polyphenols and antioxidative activity of rye extrudates is highly dependant on the moisture content of raw material and extrusion temperature.

18

Geographic variation in phytochemical constituents and allelopathic potential of Pinus halepensis barks

75%

Refifa T., Chahdoura H., Guido F., Achour L., Helal A. N.

European Journal of Biological Research

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2015

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tom 05

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nr 3

19

The influence of L-phenylalanine on the accumulation of flavonoids and phenolic acids in Vitex agnus castus (Verbenaceae) shoot cultures

75%

Skrzypczak-Pietraszek E., Piska K.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2015

|

tom 96

|

nr 1

20

Phenolic acids in rhizomes and herb of tormentil (Potentilla erecta L.)

75%

Geszprych A., Roslon W., Weglarz Z.

Herba Polonica

|

2003

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tom 49

|

nr 3-4

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