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Amadou Dicko - One of the best experts on this subject based on the ideXlab platform.

  • Optimum polyphenol and triterpene contents of Hedera Helix (L.) and Scrophularia nodosa (L.): The role of powder particle size
    Microchemical Journal, 2018
    Co-Authors: Ali Zaiter, Loïc Becker, Elie Baudelaire, Amadou Dicko
    Abstract:

    Abstract The total polyphenolic and flavonoid contents, as well as the antioxidant free radical scavenging activity (DPPH test) of different sieved powders of Hedera Helix (L.) and Scrophularia nodosa (L.), were assessed. Polyphenolic compound content varied significantly between different particle sizes (20–50; 50–100; 100–180; 180–315; > 500 μm). The intermediate classes (between 100 μm and 315 μm) exhibited the highest total polyphenol content with 28.3 mg gallic acid eq./g dry matter (DM), total flavonoid content (8.6 mg catechin eq./g DM) and antioxidant activity (23.5 Trolox eq. mg/g DM). The lowest values were observed for the unsieved powder of Hedera Helix (L.), and > 500 μm classes of Scrophularia nodosa (L.). Liquid chromatography coupled with UV detector and mass spectrometry (LC-PDA-ESI/MS) allowed identifying and quantifying polyphenols, flavonoids, iridoids, and triterpene saponins. These latter were exclusively identified by mass spectrometry; unusable signals being recorded by UV measurements. Results showed that most of the compounds presented maximal concentrations in intermediate particle sizes (100 μm–315 μm).

Elie Baudelaire - One of the best experts on this subject based on the ideXlab platform.

Jose Ramon Obeso - One of the best experts on this subject based on the ideXlab platform.

  • mineral nutrient stoichiometric variability in Hedera Helix araliaceae seeds
    Annals of Botany, 2012
    Co-Authors: Jose Ramon Obeso
    Abstract:

    †Background and Aims The analysis of variability in mineral allocation to seeds has rarely been considered in relation to allometric patterns and deviations from the allometric trajectory. Here, I examine the scaling of carbon (C), nitrogen (N), phosphorus (P) and sulfur (S) with seed mass in field-collected seeds of Hedera Helix, taking into account that brood size might influence the allocation patterns. †Methods C, N and S contents of 56 individual seeds of different sizes were analysed by combustion using a standard automated CNHS procedure. P content was determined for 200 individual seeds using spectrophotometry after acid digestion of ashed samples. This sample included seeds from different brood sizes. †Key Results C and N content both varied isometrically with seed mass and this variable explained most of the variation in their content in seeds. P and S, however, varied allometrically with seed mass. Additionally, seed mass only explained 37.3 % and 37.6 % of the total variance in P and S content, respectively. Seeds with higher mass contained proportionately more P and, furthermore, the seeds from small broods contained proportionally more P than those from large broods. †Conclusions Although seed mass in this species can be used as a surrogate of investment in C and N, it does not account for variability in allocation of nutrients such as P and S. The fact that larger seeds increased their P concentration when found in smaller broods might be a consequence of intense competition for this nutrient among developing seeds. Then, brood size may influence the mineral nutrient concentration of seeds.

Ali Zaiter - One of the best experts on this subject based on the ideXlab platform.

  • Optimum polyphenol and triterpene contents of Hedera Helix (L.) and Scrophularia nodosa (L.): The role of powder particle size
    Microchemical Journal, 2018
    Co-Authors: Ali Zaiter, Loïc Becker, Elie Baudelaire, Amadou Dicko
    Abstract:

    Abstract The total polyphenolic and flavonoid contents, as well as the antioxidant free radical scavenging activity (DPPH test) of different sieved powders of Hedera Helix (L.) and Scrophularia nodosa (L.), were assessed. Polyphenolic compound content varied significantly between different particle sizes (20–50; 50–100; 100–180; 180–315; > 500 μm). The intermediate classes (between 100 μm and 315 μm) exhibited the highest total polyphenol content with 28.3 mg gallic acid eq./g dry matter (DM), total flavonoid content (8.6 mg catechin eq./g DM) and antioxidant activity (23.5 Trolox eq. mg/g DM). The lowest values were observed for the unsieved powder of Hedera Helix (L.), and > 500 μm classes of Scrophularia nodosa (L.). Liquid chromatography coupled with UV detector and mass spectrometry (LC-PDA-ESI/MS) allowed identifying and quantifying polyphenols, flavonoids, iridoids, and triterpene saponins. These latter were exclusively identified by mass spectrometry; unusable signals being recorded by UV measurements. Results showed that most of the compounds presented maximal concentrations in intermediate particle sizes (100 μm–315 μm).

Tove Thomasen - One of the best experts on this subject based on the ideXlab platform.