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Phenolic compounds and antioxidant activity of Nepeta nuda subsp. Albiflora

100%

Teber I., Bursal E.

International Letters of Natural Sciences

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2020

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tom 79

Phenolic content and antioxidant activity of Nepeta nuda subsp. albiflora Boiss. were reported in this study. The ethanol and water extracts of Nepeta nuda subsp. albiflora were prepared and used for biochemical analyses. Antioxidant capacities of the extracts were evaluated by three different in vitro bioanalytical methods including a reducing antioxidant method and two radical scavenging antioxidant methods. The water and ethanol extracts of the plant sample were found to have effective antioxidant potentials. Phenolic content of Nepeta nuda subsp. albiflora was determined by high performance liquid chromatography (HPLC). Rosmarinic acid (182.0±4.5 µg/g), apigenin (84.5±57.6 µg/g), and quercetin (44.5±62.9 µg/g) were identified as major compounds in the ethanol extract of the plant sample. This study has a potential scientific base for further studies about Nepeta nuda subsp. albiflora related to plant biochemistry and plant based pharmacological industry.

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HPLC-determination of thiopurine methyltransferase [TPMT]-activity

100%

Brouwer C., Keizer-Garritsen J. J., De Abreu R. A., Bokkerink J. P. M., Ter Riet P. G. J. H., Trijbels J. M. F.

Cellular and Molecular Biology Letters

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1999

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tom 04

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nr 3

3

Use of a microbore ODS column for the separation of paprika [Capsicum annuum] pigments by high performance liquid chromatography

100%

Cserhati T., Forgacs E., Morais H., Ramos C.

Polish Journal of Food and Nutrition Sciences

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2002

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tom 11/52

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nr 1

The colour pigments of paprika (Capsicum annuun) were separated by reversed-phase high-performance liquid chromatography (HPLC) using normal (4 mm I.D.) and microbore (2 mm I.D.) C18 silica columns and gradient elution (water-acetonitrile-methanol). The relative standard deviation of retention times (lower than 1.5%) and that of peak areas (3-5%) were similar for both columns proving the good stability of the HPLC system. The high standard deviation of peak areas may be due to the presence of overlapping peaks. The number of separated pigment fractions was considerably higher on microbore (75) than on normal ODS column (34) proving the superiority of microbore column.

4

Determination of ionic liquids by HPLC method. Involvement in biodegradation test

88%

Garbaczewska S., Hupko J.

Pestycydy

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2007

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nr 3-4

61-66

Some chromatographic methods (RP-HPLC) for analyses of different ionic liquids have been developed. The determination methods were suitable for the study of biodegradation of these substances.

5

A novel approach to control brown dog tick, Rhipicephalus sanguineus using sustained release poly-epsilon-caprolactone-pheromone microspheres

88%

Bhoopathy D., Latha B. R., Uma T. S., Sreekumar C., Leela V.

Acta Parasitologica

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2014

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tom 59

|

nr 1

Control of brown dog tick, Rhipicephalus sanguineus was attempted by utilizing sustained release preparations of synthetic analogues of assembly pheromones. The assembly pheromone, in defined ratio, was encapsulated using poly-ɛ-caprolactone by water-in-oil-in-water double emulsion solvent evaporation technique. In the in vitro bioassay, percent mortality with test microspheres was 95.6, 64 and 44 among the unfed larvae, unfed nymph and unfed adults respectively, 24 hours post-exposure. Field trials were carried out to evaluate the efficacy of microspheres in luring and killing environmental stages of R. sanguineus in dog houses/kennels. Engorged and unfed stages in the environment were found adhered and dead on the specially designed lure.

6

Determination of hydroxymethylfurfural content in UHT milk by high-performance liquid chromatography

88%

Kuncewicz A., Michalak J.

Polish Journal of Natural Sciences. Supplement

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2004

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tom 02

103-110

7

Effect of biotic elicitors on polyphenol production in Cayratia trifolia cell suspension cultures analyzed by HPLC

88%

Arora J., Joshi A., Kanthaliya B., Khan F.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2020

|

tom 101

|

nr 1

8

Application of high-performance liquid chromatography on-line with ultraviolet-visible spectroscopy in food science

88%

Minkiewicz P., Dziuba J., Darewicz M., Nalecz D.

Polish Journal of Food and Nutrition Sciences

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2006

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tom 15/56

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nr Spec.Issue 1

The aim of the present review was to describe the application of diode-array detectors for the identification of HPLC-separated chemical compounds on the basis of their UV/Vis spectra. Diode-array detectors serve to identify compounds containing conjugated double bonds, especially aromatic compounds, and to evaluate their purity. This group of compounds includes: peptides and proteins (in that case aromatic amino acid residues are chromophores), anthocyanins and other flavonoids, other phenolic compounds, carotenoids and other dyes. The most simple strategy of interpreting UV/Vis spectra is to determine the location of absorbance maximum in zero order spectra (such a strategy is usually applied in dye analysis). The absorbance ratio at different wavelengths was used to identify and investigate structural changes in proteins and peptides. Chemometrical analysis of zero order spectra provides a basis for evaluating peak purity and choosing the background spectrum. Derivatives of spectra may be characterised via determination of convexity intervals, location of minima of second derivative, calculation of amplitudes of second and third derivatives or similarity indices between derivatives of individual spectra. The possibilities offered by UV/Vis spectroscopy cover, among others, discrimination between spectra of proteins with different contents of aromatic amino acids (mainly tyrosine and tryptophan), as well as discrimination between spectra of anthocyanins containing the same chromophore but different glycosidic moieties.

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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.

10

Synthesis and properties of model humic substances derived from gallic acid

88%

Slawinska D., Polewski K., Rolewski P., Slawinski J.

International Agrophysics

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2007

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tom 21

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nr 2

11

Determination of free- and protein primary amino acids in biological materials by high-performance liquid chromatography and photodiode array detection

88%

Czauderna M., Kowalczyk J., Niedzwiedzka K. M., Wasowska I.

Journal of Animal and Feed Sciences

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2002

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tom 11

|

nr 1

12

Determination of catechin forms in black tea using isocratic elution HLPC system

88%

Smiechowska M., Dmowski P.

Herba Polonica

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2004

|

tom 50

|

nr 3-4

In this paper the content of catechins in black fermented tea, imported to Poland by sea from China, India, Indonesia, Kenya, Malawi and Vietnam, was determined. The material was collected directly from ship cargo holds. An isocratic elution system was applied for the separation of catechins in tea. Extracts were prepared from tea samples and analysed for catechin content by HPLC. Catechin identification from chromatograms of examined tea extracts was performed by comparison of retention times with respective standards purchased from Sigma Aldrich. Chromatographic analysis by HPLC shows that examined tea contained (-)-(EGCG) in highest quantities, ranging from 148.9-292.3 mg/l, as proved by comparative analysis with a chromatogram of catechin standards, based on their retention times. Only Chinese tea contained more (-)-(EGC) - 266.2, and (-)-(EC) - 193.6, than (-)-(EGCG) - 148.9 mg/l.

13

The possibility of soil micromycetes produced the abscisic acid

88%

Buckova M., Vizarova G., Simonovicova A., Chalanyova M.

Acta Physiologiae Plantarum

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2000

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tom 22

|

nr 2

14

The use of a 2-aminoethylphosphonate by the mesophilic Penicillium commune strain

75%

Stosiek N., Klimek-Ochab M.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2018

|

tom 99

|

nr 4

15

Differences of capsaicinoids content in pericarp and paste of soft-flesh Capsicum spp. fruit

75%

Nowaczyk P., Nowaczyk L., Banach M., Krol I.

Folia Horticulturae

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2006

|

tom 18

|

nr 2

16

A comparison of numerous Cistus species and subspecies - (I) Profiles of the polyphenols with HPLC

75%

Kolling-Speer I., Wittpahl G., Hannig C., Speer K.

Polish Journal of Food and Nutrition Sciences

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2011

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tom 61

|

nr Suppl.1

17

Tocopherol content in edible plant oils

75%

Gliszczynska-Swiglo A., Sikorska E., Khmelinskii I., Sikorski M.

Polish Journal of Food and Nutrition Sciences

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2007

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tom 57

|

nr 4[A]

157-161

Edible vegetable oils were analysed for tocopherols by reversed-phase HPLC. These included refined corn, soybean, sunflower, rapeseed, grapeseed, and peanut oils, and cold-pressed extra-virgin olive, linseed, rapeseed, and sunflower oils. Total measured tocopherol concentrations varied in the range from 121 to 829 mg/kg. The contents of individual α-, (β+γ)-, and δ-tocopherols show a great diversity depending on the kind of oil. Moreover, the effect of photooxidation on the tocopherol content was studied in cold-pressed sunflower and rapeseed oils. These studies revealed only a minor decomposition of tocopherols under visible light.

18

In-house validation method for quantification of amoxicillin in medicated feedingstuffs with the use of HPLC-DAD technique

75%

Patyra E., Kwiatek K.

Journal of Veterinary Research

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2020

|

tom 64

|

nr 3

19

Identification of phenolic compounds in forest soils

75%

Debska B., Banach-Szott M.

Polish Journal of Soil Science

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2010

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tom 43

|

nr 2

The aim of the present paper was to determine the content of phenolic compounds in the organic and mineral horizons of forest soils under different tree species. The study involved taking samples from the organic and mineral horizons of forest soils located in the area of the Arboretum in Mlynany, in Slovakia. Phenolic compounds were identified with the chromatographic method (HPLC). The results showed that the content of phenolic compounds identified in the forest soils depended both on the tree species and the soil sampling depth. The Ol subhorizon on the oak stand showed a similar share of vanillyl compounds to the total of syringyl and cinnamyl compounds (52:15:33), while the Ol subhorizons on the spruce and thuja stands identified a considerable advantage of vanillyl compounds. The value of parameter V+S+C, applied as the decomposition indicator of the plant material in the soil, decreased with soil profile depth and thus decreased with an increase in the degree of organic matter humification.

20

High-performance liquid chromatographic method to evaluate the hydrogen atom transfer during reaction between 1,1-diphenyl-2-picryl-hydrazyl radical and antioxidants

75%

Leroy P., Boudier A., Tournebize J., Bartosz G., El Hani S., Bengueddour R.

Polish Journal of Food and Nutrition Sciences

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2011

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tom 61

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nr Suppl.1

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