Marija V. Dimitrijevic

Update on element content profiles in eleven wild edible mushrooms from family Boletaceae

The aim of this study was to determine and evaluate the amounts of major elements (Ca, Fe, K, Na and P), essential trace elements (Cu, Zn, Fe and Mn) and some other trace metals (Ag, Al, Co, Ni, Cr, Sr, Se, Bi, Rb) in eleven species of wild-grown common edible mushrooms from family Boletaceae (Boletus appendiculatus, Boletus edulis, Boletus regius, Boletus fechtneri, Boletus impolitus, Boletus purpureus, Boletus rhodoxanthus, Leccinum crocipodium, Leccinum pseudoscaber, Xerocomellus chrysenteron, Xerocomus badius) from Serbia. The measurements of major elements (Ca, Fe, K, Na and P) were carried out by inductively coupled plasma optical emission spectrometer (ICP-OES), while analytical measurements of the rest of studied elements were performed using an inductively coupled plasma mass spectrometer (ICP-MS), after microwave digestion. The results showed that the element concentrations were species-dependent. Potassium and phosphorous concentrations were found to be greater than those of the other mineral constituents in all tested species. Multivariate analysis included principal component analysis (PCA) and hierarchical cluster analyses (HCA). HCA grouped mushrooms in three statistically significant clusters, while PCA indicated connection between analyzed metals. Also, this paper highlights the importance of essential and nonessential elements of human health and their daily intake.

Optimization of the QuEChERS extraction procedure for the determination of polycyclic aromatic hydrocarbons in soil by gas chromatography-mass spectrometry

Polycyclic aromatic hydrocarbons (PAHs) are listed as pollutants of great concern and the development of fast and reliable analytical procedures is a modern day challenge. The aim of this study was to optimize the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) technique, in order to establish an efficient method for the extraction of 16 priority PAHs from soil, using various sorbent and solvent system combinations, followed by GC-MS analysis. The best results were obtained using acetonitrile/water as the extraction solvent and diatomaceous earth as the dispersive solid phase extraction sorbent. The proposed method is rapid, accurate, precise, as well as much cheaper and simpler than other methods used for the extraction of PAHs from soil. The optimized method was successfully applied on real soil samples from an urban area of Nis, Serbia. Analysis of real soil samples showed contamination of soil with mostly light PAHs, where acenaphthene was predominant. The content of total PAHs varied from 345.65 to 27 314.30 μg kg−1, with a mean of 3646.39 μg kg−1. Only three samples contained elevated amounts of PAHs according the Gazette of the Republic of Serbia.

Screening of antioxidant, antimicrobial and antiradical activities of twelve selected Serbian wild mushrooms

This study was undertaken to evaluate and compare the antioxidant, antimicrobial and antiradical activities of twelve wild edible mushrooms from Serbia. The antioxidant activity was evaluated by five different methods: DPPH, ABTS, total reducing power (TRP), ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC). Folin–Ciocalteu total phenolic compounds (TPC) were also determined. The present study shows that the ethanol extract of Boletus regius has the highest antioxidant values (10.997 ± 0.891 mg mL−1 in DPPH; 0.771 ± 0.004 mg AAE per mg dw in TRP; 56.924 ± 0.022 mmol Fe per mg dw in FRAP; 21.738 ± 0.108 mg TE per mg dw in CUPRAC; 173.125 ± 0.475 mg GAE per mg dw in TPC). This is the first report on the evaluation of the antioxidant activity of ethanol extracts of mushrooms by the CUPRAC method. The in vitro antimicrobial activity was investigated by the microdilution method. This is the first report on the antimicrobial activity for many analyzed mushroom species. The highest antiradical activity unit (EAU515) was from Polyporus squamosus (6.349 EAU515). We determined the antioxidant capacity and the antioxidant potency composite index (ACI) was calculated. Agglomerative hierarchical clustering (AHC) was applied to investigate the similarities between the used methods for antioxidant activities. PCA was used for determining the number of variables to explain the observed variances in the antioxidant activity data of the examined wild mushroom species.

Elemental Composition of Wild Edible Mushrooms from Serbia

The elemental composition of four wild edible mushroom species was determined by inductively coupled plasma optical emission spectrometry (ICP OES): scotch bonnet (Marasmius oreades), chanterelle (Cantarellus cibarius), porcini (Boletus edulis), and peppery milk-cap (Lactarius piperatus). Mushrooms are a potassium-rich food, which was confirmed in this study. M. oreades contained the highest concentration of almost all elements, except for cadmium, potassium, phosphorus, and lead. Lead and cadmium were present but at concentrations that are not hazardous to human health. A principal component analysis loading plot for elemental composition demonstrated that 95.51 percent of the total variance was present in the first two principal components. Cluster analysis separated the elements into three statistical significant clusters.

Dispersive solid-phase extraction clean up combined with Soxhlet extraction for the determination of 16 PAHs in soil samples by GC-MS

ABSTRACT Dichloromethane soil samples extracts were prepared using Soxhlet extraction technique, and after clean-up step, gas chromatography-mass spectrometry analysis of 16 priority polycyclic aromatic hydrocarbons (PAHs) was carried out. A comparison of dispersive solid-phase extraction (dSPE) and column chromatography (cC), as clean-up techniques, was evaluated. Six different sorbents (silica, diatomaceous earth, primary–secondary amine, C18, clinoptilolite and florisil) were tested as dispersive clean-up sorbents versus activated silica and alumina for cC. Best results for three concentration levels among dSPE were obtained using diatomaceous earth, with recovery values in the range of 75–112% for 13 of 16 analysed compounds, while cC recoveries were in the range of 75–111% for all analysed PAHs. Analysis of 12 soil samples from urban area of Niš (Serbia) singled out acenaphthene as the most abundant compound.

Comparative Study of Fatty Acids Profile in Eleven Wild Mushrooms of Boletacea and Russulaceae Families

Eleven species of wild mushrooms which belong to Boletaceae and Russulaceae families were examined by gas chromatography (GC) and gas chromatography–mass spectrometry (GC/MS) analysis for the presence of fatty acids. As far as we know, the fatty acid profiles of B. purpureus and B. rhodoxanthus were described for the first time. Twenty‐six fatty acids were determined. Linoleic (19.5 – 72%), oleic (0.11 – 64%), palmitic (5.9 – 22%) and stearic acids (0.81 – 57%) were present in the highest contents. In all samples, unsaturated fatty acids dominate. Agglomerative hierarchical clustering was used to display the correlation between the fatty acids and their relationships with the mushroom species. Based on the fatty acids profile in the samples, the mushrooms can be divided into two families: Boletaceae and Russulaceae families, using cluster analysis.

Comprehensive Evaluation of Antioxidant Activity of Ribes berry Fruit Species: A Chemometric Approach

ABSTRACT Currant fruit extracts were characterized by (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, 2,2-azinobis-3 ethyl benzothiazoline-6-sulfonic acid cation decolorization activity, total reducing power, cupric ion reducing antioxidant power, and ferric ion reducing antioxidant power (FRAP) assays to evaluate their antioxidant activity. All five antioxidant assays revealed the highest antioxidant activity to be present for the black currants. The highest concentrations of phenolics were present in the black currants (1690 ± 10 mg gallic acid equivalents (GAE)/100 g fresh weight), while the lowest value was obtained in the white currants (579 ± 5 mg GAE/100 g fresh weight). The correlation between the total phenolic content and antioxidant activity assays was evaluated using regression analysis. A significant positive correlation was obtained between the total phenols and the cupric ion reducing antioxidant power (r = 0.97, p < 0.05), followed by that between the total phenols and FRAP (r = 0.93, p < 0.05). Hierarchical cluster analysis separated these selected fruit species into two statistically significant clusters with black currants as a distinctive cluster.

Optimized Ultrasonic Extraction for the Determination of Polyaromatic Hydrocarbons by Gas Chromatography – Mass Spectrometry

ABSTRACT The presence of polycyclic aromatic hydrocarbons (PAHs) in soil is an issue of concern due to their harmful effects on human health. The goal of this study was to optimize ultrasonic extraction to establish an efficient, easy, and low-cost method for the determination of 16 priority PAHs in soil. The time of extraction and solvent systems were optimized with the analysis by gas chromatography–mass spectrometry. The method was validated, and the optimum results were obtained using 1:1 cyclohexane:acetone and 1:1 hexane:acetone solvent systems with 30- and 60-min sonication times.

Characterization of Pepper Genotypes from Serbia as a Function of Maturity by Antioxidant Activity with Chemometric Analysis

ABSTRACT The antioxidant activities and total phenolic concentrations of nine pepper genotypes from Serbia in various maturity stages were evaluated using 2,2-diphenyl-1-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), total reducing power, ferric ion-reducing antioxidant power, and cupric ion-reducing antioxidant capacity assays. The effect of maturation on the antioxidant activity of these pepper genotypes had not been evaluated to date. Generally, ripening increases antioxidant activity and total phenolic concentration in all genotypes except for Kameleon. Kameleon peppers exhibited higher total phenolic concentrations and antioxidant activity when immature. From the nutritional point of view, red peppers are the most suitable because they provided higher antioxidant activity values than green and yellow peppers. Statistical analysis showed strong correlation between cupric ion-reducing antioxidant capacity and other assays, so if rapid assessment of antioxidant activity is needed, the cupric ion-reducing antioxidant capacity is the method of choice. Two statistically significant clusters were obtained using chemometric analysis, grouping the mature peppers into the first and immature peppers into the second, as evidenced by principal component analysis. Principal component analysis allowed the classification of the mature and immature peppers.

Chemometric approach to evaluate heavy metals' content in Daucus carota from different localities in Serbia

The aim of this study was to evaluate heavy metal content in carrots (Daucus carota) from the different localities in Serbia and assess by the cluster analysis (CA) and principal components analysis (PCA) the heavy metal contamination of carrots from these areas. Carrot was collected at 13 locations in five districts. Chemometric methods (CA and PCA) were applied to classify localities according to heavy metal content in carrots. CA separated localities into two statistical significant clusters. PCA permitted the reduction of 12 variables to four principal components explaining 79.94% of the total variance. The first most important principal component was strongly associated with the value of Cu, Sb, Pb and Tl. This study revealed that CA and PCA appear useful tools for differentiation of localities in different districts using the profile of heavy metal in carrot samples. [Projekat Ministarstva nauke Republike Srbije, br. 172051]