scholarly journals Chemical Composition and Antioxidant Activity of Walnut Pollen Samples

2015 ◽  
Vol 43 (2) ◽  
pp. 361-365 ◽  
Author(s):  
Sina COSMULESCU ◽  
Ion TRANDAFIR ◽  
Violeta NOUR
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Mineral Composition ◽  
Colorimetric Assay ◽  
Colorimetric Method ◽  
Antioxidant Properties ◽  
Total Phenols ◽  
Total Flavonoids Content ◽  
The Subject

Chemical composition of pollen is highly varied depending on the plant species from which it comes and has been the subject of numerous comparative studies. The aim of this study was to determine chemical composition and antioxidant activity of walnut pollen samples and compare them with those of bee pollen. Total phenols content, total flavonoids content, antioxidant activity and mineral composition were studied using walnut pollen samples from three walnut genotypes cultivated in Romania. Total phenols content was determined by colorimetric assay and their amount varied between 10.8 and 17.64 mgGAE/g per genotype. Determination of flavonoids was done by aluminium nitrate colorimetric method and total flavonoid contents in walnut pollen ranged from 7.32 to 7.95 mgQE/g. The antioxidant capacity of pollen extracts was assessed through the scavenging effects on DPPH and a concentration-dependent genotype, and it varied between 13.78 and 15.04 mg Trolox/g. In terms of mineral composition, walnut pollen appears to be a good source of potassium (859.14 mg/100 g), magnesium (263.77 mg/100 g), calcium (71.72 mg/100 g), iron (27.19 mg/100 g), sodium (10.52 mg/100 g), zinc (5.69 mg/100 g), manganese (3.98 mg/100 g), copper (1.28 mg/100 g), chromium (0.39 mg/100 g) and selenium (0.036 mg/100 g). The results obtained indicate that walnut pollen is an important source of total phenols showing antioxidant properties and mineral composition that could be beneficial to human health.

scholarly journals Influence of the processing method on the chemical composition and antioxidant activity of raspberries

2021 ◽  
pp. 388-392
Author(s):  
И.А. Громова ◽  
М.С. Воронина ◽  
Н.В. Макарова
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Antioxidant Properties ◽  
Great Influence ◽  
Water Extract ◽  
Total Content ◽  
Waste Products ◽  
Fresh Frozen ◽  
Ethanol Extracts

Большое влияние на здоровье человека оказывают вещества, проявляющие антиоксидантный эффект, в значительной степени содержащиеся в ягодах малины и отходах сокового производства от данной ягоды, а именно свежезамороженной ягоде, свежевыжатом соке, водной вытяжке, сырых и высушенных выжимках и концентрированном соке. Целью работы стало изучение химического состава и антиоксидантной активности ягод малины и отходов сокового производства, наблюдение за изменением показателей исследуемых характеристик при механической и тепловой обработке ягод малины и выбор оптимального варианта. При проведении исследований были использованы следующие методы: определение общего содержания антоцианов; определение общего содержания фенольных соединений; определение общего содержания флавоноидов; определение антирадикальной активности; определение восстанавливающей силы; исследование антиоксидантных свойств с использованием модельной системы линолевой кислоты. Все методы по определению содержания антиоксидантов проводились на этанольных экстрактах. Установлено, что использование экстракции для ягод и отходов сокового производства позволяет более точно определить содержание исследуемых показателей. Выявлено, что наибольшая антиоксидантная активность 94,5-98,4 % отмечена в малине и водной вытяжке из нее. A great influence on human health is exerted by substances exhibiting an antioxidant effect, largely contained in raspberries and their juice waste products, specifically in fresh-frozen berries, fresh squeezed juice, water extract, raw and dried pomace and concentrated juice. The aim of the work was to study chemical composition and antioxidant activity of raspberries and their juice waste products, monitor changes in the parameters of the studied characteristics during mechanical and thermal processing of raspberries and select the optimal option. The following methods were used during the research: determination of the total content of anthocyanins; determination of the total content of phenolic compounds; determination of the total content of flavonoids; determination of antiradical activity; determination of regenerating power; study of antioxidant properties using a model system of linoleic acid. All methods for determining the content of antioxidants were carried out on ethanol extracts. It was established that using of extraction for berries and juice waste products made it possible to determine more precisely the content of the studied indicators. It was also revealed that the highest antioxidant activity of 94.5% - 98.4% was observed in raspberries and their water extract.

scholarly journals Bioactive Compounds, RP-HPLC Analysis of Phenolics, and Antioxidant Activity of Some Portuguese Shrub Species Extracts

2011 ◽  
Vol 6 (12) ◽  
pp. 1934578X1100601 ◽  
Author(s):  
Ângelo Luís ◽  
Fernanda Domingues ◽  
Ana Paula Duarte
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Activity Index ◽  
Colorimetric Method ◽  
Antioxidant Properties ◽  
Raw Material ◽  
Total Phenolic ◽  
Methanolic Extracts ◽  
Rp Hplc

In the ecosystem of Serra Da Estrela, some plant species have the potential to be used as raw material for extraction of bioactive products. The goal of this work was to determine the phenolic, flavonoid, tannin and alkaloid contents of the methanolic extracts of some shrubs ( Echinospartum ibericum, Pterospartum tridentatum, Juniperus communis, Ruscus aculeatus, Rubus ulmifolius, Hakea sericea, Cytisus multiflorus, Crataegus monogyna, Erica arborea and Ipomoea acuminata), and then to correlate the phenolic compounds and flavonoids with the antioxidant activity of each extract. The Folin-Ciocalteu's method was used for the determination of total phenols, and tannins were then precipitated with polyvinylpolypyrrolidone (PVPP); a colorimetric method with aluminum chloride was used for the determination of flavonoids, and a Dragendorff's reagent method was used for total alkaloid estimation. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene bleaching tests were used to assess the antioxidant activity of extracts. The identification of phenolic compounds present in extracts was performed using RP-HPLC. A positive linear correlation between antioxidant activity index and total phenolic content of methanolic extracts was observed. The RP-HPLC procedure showed that the most common compounds were ferulic and ellagic acids and quercetin. Most of the studied shrubs have significant antioxidant properties that are probably due to the existence of phenolic compounds in the extracts. It is noteworthy to emphasize that for Echinospartum ibericum, Hakea sericea and Ipomoea acuminata, to the best of our knowledge, no phytochemical studies have been undertaken nor their use in traditional medicine been described.

The Need for Using An Enzymatic Colorimetric Assay in Creatinine Determination of Peritoneal Dialysis Solutions

1990 ◽  
Vol 10 (1) ◽  
pp. 89-92 ◽  
Author(s):  
Liliane Larpent ◽  
Christian Verger
Keyword(s):  
Peritoneal Dialysis ◽  
Reliable Method ◽  
Colorimetric Assay ◽  
Colorimetric Method ◽  
Peritoneal Membrane ◽  
Creatinine Kinetics ◽  
Dialysis Solutions ◽  
Peritoneal Dialysis Solutions ◽  
Enzymatic Test

The fate of the peritoneal membrane on continuous ambulatory peritoneal dialysis (CAPD) is usually evaluated through the modification of its permeability to various solutes as glucose, creatinine, and urea. Therefore, the accuracy of the methods used for measurements of creatinine is of great importance. A particular problem does exist for creatinine determination as it may be influenced by the presence of glucose. We studied a new enzymatic colorimetric method for creatinine determination in peritoneal dialysis solutions which contain high dextrose concentrations. Creatinine was measured in plasma, urine, and dialysate from 18 patients on CAPD and in pure dextrose solutions, with an enzymatic test (Boehringer Mannheim) and with Jaffe's reaction on two different analyzers: Astra (Beckman) and Eris (Merck). Creatinine results were similar with both assays (Jaffe's reaction and enzymatic test) when measured in blood and urine. However the Jaffe's reaction gave higher creatinine results than the enzymatic test (p < 0.001), when assays were performed in peritoneal dialysis solutions and in pure glucose solutions. In addition, it appeared that other components of dialysis solutions, mainly calcium chloride, influenced unpredictably the results of creatinine with the Jaffe's reaction. We conclude that specific enzymatic test is a more accurate and reliable method to evaluate creatinine kinetics through the peritoneal membrane when determined in CAPD solutions.

scholarly journals Chemical Composition, In Vitro and In Silico Antioxidant Potential of Melissa officinalis subsp. officinalis Essential Oil

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1081
Author(s):  
Matilda Rădulescu ◽  
Călin Jianu ◽  
Alexandra Teodora Lukinich-Gruia ◽  
Marius Mioc ◽  
Alexandra Mioc ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
In Silico ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Inhibitory Effect ◽  
Melissa Officinalis ◽  
Β Carotene

The investigation aimed to study the in vitro and in silico antioxidant properties of Melissa officinalis subsp. officinalis essential oil (MOEO). The chemical composition of MOEO was determined using GC–MS analysis. Among 36 compounds identified in MOEO, the main were beta-cubebene (27.66%), beta-caryophyllene (27.41%), alpha-cadinene (4.72%), caryophyllene oxide (4.09%), and alpha-cadinol (4.07%), respectively. In vitro antioxidant properties of MOEO have been studied in 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging, and inhibition of β-carotene bleaching assays. The half-maximal inhibitory concentration (IC50) for the radical scavenging abilities of ABTS and DPPH were 1.225 ± 0.011 μg/mL and 14.015 ± 0.027 μg/mL, respectively, demonstrating good antioxidant activity. Moreover, MOEO exhibited a strong inhibitory effect (94.031 ± 0.082%) in the β-carotene bleaching assay by neutralizing hydroperoxides, responsible for the oxidation of highly unsaturated β-carotene. Furthermore, molecular docking showed that the MOEO components could exert an in vitro antioxidant activity through xanthine oxidoreductase inhibition. The most active structures are minor MOEO components (approximately 6%), among which the highest affinity for the target protein belongs to carvacrol.

Aktywność przeciwutleniająca i przeciwbakteryjna miodu, propolisu oraz pyłku kwiatowego

2020 ◽  
Vol 21 (3) ◽  
Author(s):  
Magdalena Woźniak ◽  
Lucyna Mrówczyńska ◽  
Anna Sip ◽  
Marta Babicka ◽  
Tomasz Rogoziński ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Pathogenic Bacteria ◽  
Radical Scavenging Activity ◽  
Colorimetric Method ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Total Content ◽  
Diffusion Method ◽  
Bacterial Strains

Introduction. Honey, propolis and pollen belong to bee products that have beneficial biological properties. These products exhibit e.g. antibacterial, antifungal and antioxidant properties. Due to biological activity and natural origin, bee products are used, e.g. in the food industry, cosmetology and pharmacy. Aim. The aim of the study was to compare the antioxidant and antibacterial activity of honey, propolis and pollen from an apiary located in Wielkopolska Province. Material and methods. Honey, propolis and pollen used in this study came from the same apiary located in Wielkopolska Province. The antioxidant potential of bee products was evaluated applying DPPH· free radical scavenging activity assay. The antimicrobial activity of the tested bee products was determined by the point-diffusion method against 13 strains of pathogenic and potentially pathogenic bacteria. In addition, the total content of phenolic compounds in honey, propolis and pollen was determined by the colorimetric method. Results. Propolis exhibited higher antioxidant activity, in comparison to honey and pollen. The antiradical activity of propolis was equal to 80% approx. activity of Trolox, the standard antioxidant. Among tested bee products, propolis was characterized by the highest total phenols content. In addition, honey, propolis and pollen showed antagonistic activity against tested bacterial strains. Conclusions. The obtained results indicate that among the tested bee products of native origin, i.e. honey, propolis and pollen, propolis characterized by the highest antioxidant activity and the total content of phenolic compounds. In addition, all bee products showed bactericidal activity against the tested bacterial strains.

scholarly journals RELATIONSHIP BETWEEN ANTIOXIDANT PROPERTIES AND NUTRITIONAL COMPOSITION OF SOME GALACTOPOIETICS HERBS USED IN INDONESIA: A COMPARATIVE STUDY

2016 ◽  
Vol 8 (12) ◽  
pp. 236 ◽  
Author(s):  
Ade Chandra Iwansyah ◽  
Rizal M. Damanik ◽  
Lilik Kustiyah ◽  
Muhammad Hanafi
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Total Phenolics ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Nutritional Composition ◽  
Total Flavonoids ◽  
Wide Range ◽  
Phenolics Content

<p><strong>Objective: </strong>The objectives of this research were to evaluate and compare the antioxidant activity; phenolics and flavonoids contents; and chemical composition of some galactopoietic herbs used in Indonesia and to find a possible relationship between antioxidant activity; phenolics, flavonoids and chemical composition of these plants.</p><p><strong>Methods: </strong>A wide range of analytical parameters was studied, including yield; pH; water activity (a<sub>w</sub>); total color difference; phenolics and flavonoids content; moisture; ash; protein; fat; carbohydrate; fiber; calcium; zinc; magnesium; potassium; iron content; and the data were analyzed by partial least squares (PLS) regression analysis and principal component analysis (PCA) to evaluate the correlation between the parameters and classification of the plants. Folin–cioceltaeu assay, aluminum chloride assay and DPPH scavenging assay were used to evaluate of total phenolics content and free radical scavenging activity of the ethanolic extract of galactopoietic herbs.</p><p><strong>Results: </strong>All of the galactagogue herbs, <em>viz</em>. <em>Plectranthus amboinicus </em>(Lour.) (PA), <em>Sauropus androgynus</em> (SA), <em>Moringa oleifera</em> (MO), and <em>Carica papaya</em> leaves (CP) exhibited good results of TPC, TFC and antioxidant activity. MO contained the highest average of total phenolics content (53.89 mg GAE/g). SA with a ratio of total flavonoids to total phenolics (TF/TP) which is 1.59 contained the highest average of total flavonoids and antioxidant activity (IC<sub>50</sub>), 43.63 mg QE/g and 126.13 μg/ml, respectively, followed by MO&gt;CA&gt;PA. Based on PLS and PCA analysis, antioxidant activity correlated with fat, protein, phenolics content, flavonoids content and pH, but only the total flavonoids content correlated strongly with antioxidant activity.<strong></strong></p><p><strong>Conclusion: </strong>This provides useful data about the studied relationships and chemical patterns in some galactopoietic herbs used and provides a helpful tool for understanding much more about the interpretation of results from the experiments and the mechanism of biosynthesis in plants.</p>

scholarly journals Eugenia Klotzschiana O. Berg Fruits as New Sources of Nutrients: Determination of their Bioactive Compounds, Antioxidant Activity and Chemical Composition

2019 ◽  
Vol 62 ◽  
Author(s):  
Nárgella Silva Carneiro ◽  
Cássia Cristina Fernandes Alves ◽  
Caroline Cagnin ◽  
Celso Martins Belisario ◽  
Marco Antônio Pereira da Silva ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Bioactive Compounds

scholarly journals PHYTOCHEMICAL AND ANTIOXIDANT COMPOSITION IN ACCESSIONS OF THE MANGABA ACTIVE GERMPLASM BANK

2021 ◽  
Vol 34 (1) ◽  
pp. 228-235
Author(s):  
PRISCILLA SANTANA SANTOS ◽  
LISIANE DOS SANTOS FREITAS ◽  
EVANDRO NEVES MUNIZ ◽  
JOSEFA GRASIELA SILVA SANTANA ◽  
ANA VERUSKA CRUZ DA SILVA
Keyword(s):  
Principal Component Analysis ◽  
Antioxidant Activity ◽  
High Performance Liquid Chromatography ◽  
High Performance ◽  
Antioxidant Properties ◽  
Principal Component ◽  
Total Phenols ◽  
Germplasm Bank ◽  
Fruit Species ◽  
Hancornia Speciosa

ABSTRACT Mangaba (Hancornia speciosa Gomes) is a fruit species native to Brazil, belonging to the Apocynaceae family. Its cultivation is predominantly extractivist and its antioxidant properties have been recently reported. The objective of this study was to evaluate the bioactive compounds and antioxidant activity in fruits of accession from the Active Germplasm Bank of Embrapa Coastal Tablelands (BI, CA, LG, PR, PT and TC). The extracts were analyzed by high-performance liquid chromatography (HPLC), which identified chlorogenic acid (93.71 - 131.66 mg.100g-1), ferulic acid (0.85 - 2.27 mg.100g-1) and rutin (238.59 -442.94 mg.100g-1). The accessions CA and PR showed the highest values of total phenols (1179.39 and 1167.05 mg GAE.100g-1, respectively). The accessions CA and TC had the highest concentration of the major compound rutin (436.78 and 442.94 mg.100g-1, respectively). Antioxidant activity values ranged from 125.95 to 158.67 g.g-1 DPPH. Principal component analysis grouped the accessions into four groups, due to the genetic variability verified in previous studies. The results will be useful to guide actions of selection and future breeding program of the species.

Quantitative Determination of Thiourea in Citrus Fruits

1977 ◽  
Vol 60 (3) ◽  
pp. 699-701
Author(s):  
Bernadette Mandrou ◽  
Suzanne Brun ◽  
Amara Kingkate
Keyword(s):  
Colorimetric Assay ◽  
Colorimetric Method ◽  
Extraction Technique ◽  
Citrus Fruits ◽  
Alumina Column ◽  
Orange Peels ◽  
Ultraviolet Reflectance ◽  
Spectrometric Measurements ◽  
Colorimetric Reaction

Abstract A quantitative method for thiourea determination in orange peels is proposed, with direct reflectance spectrometric measurements on chromatoplates. Thiourea is separated on a silica gel plate with methanol-chloroform (10+90), and the spots are characterized with 2,6-dichloroquinone chloroimide; this colorimetric reaction is unstable, so thiourea is quantitated on the chromatogram by direct ultraviolet reflectance spectrometric measurements at 240 nm. Comparison between this method and the AOAC colorimetric method shows interferences and higher results in the colorimetric assay. By slightly modifying the extraction technique, such as purifying the extract on an alumina column, it is possible to decrease these interferences and to avoid erroneous results with the AOAC colorimetric method. For both methods, colorimetry in solution and reflectometry on chromatoplates, applied after the proposed extraction technique, the sensitivity is about 1 ppm and the reliabilities are similar.

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