Flavonoids and Phenolic Acids from Aerial Part of Ajuga integrifolia (Buch.-Ham. Ex D. Don): Anti-Shigellosis Activity and In Silico Molecular Docking Studies.

Shigellosis is one of the major causes of death in children worldwide. Flavonoids and phenolic acids are expected to demonstrate anti-shigellosis activity and anti-diarrheal properties. The aerial part of A. integrifolia is commonly used against diarrhea. This study aimed to identify flavonoids and phenolic acids responsible for this therapeutic purpose. Antioxidant activity, total phenol content, and total flavonoid content were determined. The antibacterial activity of the aerial part against Shigella spp. was also tested using the agar well diffusion method. HPLC analysis was performed using UHPLC-DAD for different extracts of the aerial part. Autodock Vina in the PyRx platform was used to screen responsible components. Ciprofloxacin was used as a reference drug. An enzyme taking part in pyrimidine biosynthesis was used as a target protein. Molecular docking results were visualized using Discovery Studio and LigPlot1.4.5 software. Antioxidant activity, total phenol content, and total flavonoid content are more significant for the aerial part of A. integrifolia. From HPLC analysis, the presence of the flavonoids, quercetin, myricetin, and rutin and the phenolic acids gallic acid, chlorogenic acid, and syringic acid were identified from the aerial part of A. integrifolia. Regarding the antibacterial activity, the aerial part shows considerable activity against Shigella spp. Binding energies, RMSD and Ki values, interaction type, and distance are considered to identify the components most likely responsible for the therapeutic effects and observed activity. Antioxidant activity, total phenol content, and total flavonoid content of the aerial part are in line with anti-shigellosis activity. The top five components that are most likely potentially responsible for therapeutic purposes and anti-shigellosis activity are chlorogenic acid, rutin, dihydroquercetin, dihydromyricetin, and kaempferol.

Targeted HPTLC Profile, Quantification of Flavonoids and Phenolic Acids, and Antimicrobial Activity of Dodonaea angustifolia (L.f.) Leaves and Flowers.

In East Africa, Dodonaea angustifolia (L.f.) is a well-known medicinal herb. Its leaf is primarily studied in light of its ethnobotanical use. In terms of phytochemistry and biological activity, its flower is not studied. In a prior study, our team looked into phytochemical screening, antioxidant activity, and total phenolic levels. This study aims to compare the profiles and biological activities of the leaf and flower samples of D. angustifolia and to present therapeutic alternatives. The leaf and flower sample powders were extracted with methanol using ultrasound-assisted extraction (UAE). HPTLC profile was obtained using CAMAG-HPTLC equipped with VisionCATS software. Antimicrobial agar well diffusion assay and minimum inhibition concentration (MIC) were determined. The leaf and flower extracts of D. angustifolia showed antibacterial activity with a MIC value of 20 µg/mL against Enterococcus faecalis and Listeria monocytogenes. Similarly, 40 µg/mL was found to be effective against Aspergillus flavus. D. angustifolia flower is a rich source of flavonoids and phenolic acids. Because of its antibacterial properties and profile, which are almost the same, the flower is emerging as a viable option for medicinal alternatives.

Lead, cadmium and mercury contents and bioaccumulation potential of wild edible saprophytic and ectomycorrhizal mushrooms, Croatia.

Lead (Pb), cadmium (Cd), and mercury (Hg) contents in ten species of edible mushrooms in Trakoscan, Croatia were determined. In addition, the similarity between the studied species was determined by cluster analysis. The caps and stipes of the fruiting bodies were analysed separately. The analyses were carried out by inductively coupled plasma - optical emission spectrometry (ICP-OES). The greatest mean lead concentrations of 1.91 and 1.60 mg kg -1 were determined in caps and stipes of Macrolepiota procera. The greatest mean concentrations of cadmium (3.23 and 2.24 mg kg-1) were determined in caps and stipes of Agaricus campestris and of mercury (2.56 and 2.35 mg kg-1) in Boletus edulis. In terms of the anatomical parts of the fruiting body (cap-stipe), a considerably greater concentration of the analysed elements was found in the cap for all mushroom species. According to calculated bio-concentration factors, all the examined species were found to be bio-accumulators of Cd and Hg. On the basis of the accumulation of the studied metals, great similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation was obtained by cluster analysis.

Genomic Characterization of Local Croatian Sheep Breeds-Effective Population Size, Inbreeding & Signatures of Selection.

The Istrian (IS) and the Pag sheep (PS) are local Croatian breeds which provide significant income for the regional economy and have a cultural and traditional importance for the inhabitants. The aim of this study was to estimate some important population specific genetic parameters in IS (N = 1293) and PS (N = 2637) based on genome wide SNPs. Estimates of linkage disequilibrium effective population size (Ne) evidenced more genetic variability in PS (Ne = 838) compared to IS (Ne = 197), regardless of historical time (both recent and ancient genetic variability). The discrepancy in the recent genetic variability between these breeds was additionally confirmed by the estimates of genomic inbreeding (FROH), which was estimated to be notably higher in IS (FROH>2 = 0.062) than in PS (FROH>2 = 0.029). The average FROH2-4, FROH4-8, FROH8-16, and FROH>16 were 0.26, 1.65, 2.14, and 3.72 for IS and 0.22, 0.61, 0.75, and 1.58 for PS, thus evidencing a high contribution of recent inbreeding in the overall inbreeding. One ROH island with > 30% of SNP incidence in ROHs was detected in IS (OAR6; 34,253,440-38,238,124 bp) while there was no ROH islands detected in PS. Seven genes (CCSER1, HERC3, LCORL, NAP1L5, PKD2, PYURF, and SPP1) involved in growth, feed intake, milk production, immune responses, and resistance were associated with the found autozygosity. The results of this study represent the first comprehensive insight into genomic variability of these two Croatian local sheep breeds and will serve as a baseline for setting up the most promising strategy of genomic Optimum Contribution Selection.

Impact of titanium dioxide (TiO2) nanoparticle and liquid leachate of mushroom compost on agronomic and biochemical response of marigold (Tagetes erecta L.) under saline stress.

The cultivation of ornamental horticultural crops under salinity stress has been a challenge for growers all over the world. In this study, an attempt was made for pot cultivation of Marigold (Tagetes erecta L. var. Pusa Basanti Gainda) in salt-stressed (SS) soil (150 mM) with the combined use of mushroom compost leachate (CL) and foliar application of titanium dioxide nanoparticles (TiO2-NPs). For this purpose, a total of six pot treatments, i.e., borewell water (BW; control), T1 (BW with SS), T2 (BW with SS and TiO2-NPs), T3 (CL supplemented), T4 (CL with SS), and T5 (CL with SS and TiO2-NPs) were conducted in triplicate. The results of this study showed that CL supplementation significantly (p < 0.05) improved the physicochemical i.e., pH (14.5%), electrical conductivity (32.9%), total nitrogen (27.4%), total phosphorus (247.6%)), and nutrient (organic matter: 119.6%) profiles of soil which later helped in higher growth (30-35%) and yield (5.4-40.7%) of T. erecta. In CL-based treatments, the biochemical constituents were significantly (p < 0.05) higher than those in BW-irrigated ones. Also, the levels of selected stress defense enzymes were significantly increased under SS treatment but reduced under TiO2-NP application. Overall, it was observed that the combined application of CL and TiO2-NPs (T5 treatment) was the most helpful treatment for enhanced germination, growth, yield, biochemical parameters, and better plant enzymatic activities to cope with saline stress. This study provides a mechanistic understanding of T. erecta plants under saline stress which is crucial for the development of targeted interventions aimed at improving plant tolerance to saline conditions.

Preface to the Special Issue 'Heavy Metals in Mushrooms'.

Population growth, intensive industrialization and urbanization have led to environmental pollution, especially soil and water pollution [...].

Development of a solid phase microextraction method for the determination of nicotine in dried mushrooms.

Official control of EU market foodstuffs repeatedly reports high nicotine levels in dried wild mushrooms without any clear scientific consensus about their origin. The advised constant monitoring calls for improvements to existing methods. For this purpose, our aim was to develop a headspace solid phase microextraction (HS-SPME) method coupled to gas chromatography with mass spectrometric detection (GC-MS) that would eliminate the need for extensive sample pre-treatment. The type of fiber coating, amount of sample, extraction temperature and time, desorption time and salt addition were investigated and optimized as parameters affecting the SPME procedure. The optimized conditions were used to validate a quantitative method for nicotine analysis by matrix-matched calibration and isotopically labelled internal standard correction. The method provided good linearity (r2 = 0.9994) over the tested concentration range (0.025-1 mg kg-1), low detection limit (0.005 mg kg-1) and low quantification limit (0.017 mg kg-1) for nicotine, being below the EU foodstuff regulations. For both of the tested concentration levels (0.050 and 0.200 mg kg-1), precision expressed as relative standard deviation was below 10% (4.5% and 8.5%, respectively), while accuracy was 98.2% and 100.3%. The optimized method was then used to determine nicotine levels in 18 samples of dried Boletus mushrooms from southeastern European countries entering the EU market. We demonstrated our HS-SPME procedure to be fast, simple, sensitive, solvent-free, cost-effective and thus suitable for controlling consumer safety regarding nicotine level in dried mushrooms.

Essential Trace and Toxic Element Content in Lacaune Sheep Milk during Lactation.

The aim of this study was to investigate the concentrations of essential trace and toxic elements in the milk of Lacaune sheep during lactation in intensive rearing systems. This research was conducted with 30 Lacaune sheep that were monitored in the early (60 days of lactation), medium (120 days of lactation), and late (180 days of lactation) stages of lactation. The sheep were fed a pelleted feed mixture (1 kg/day), a cereal mixture (600 g/day), and alfalfa hay (ad libitum). The essential (Fe, Zn, Cu, Co, Mn, Mo, Se, Cr, and Ni) and toxic element (heavy metals: Cd, Pb, As, and Hg) concentrations in the feed and milk were determined using an inductively coupled plasma mass spectrometer. Significant variations in the main essential trace and toxic elements, except for the Mo, Se, Ni, As, and Hg concentrations, were found in the milk of Lacaune sheep during lactation. As lactation progressed, in the late stage of lactation, significantly higher concentrations of Co, Mn, Mo, Cr, and Pb were found, while Zn and Cu in the milk of Lacaune sheep decreased significantly (4.15 and 0.21 mg/kg) compared to their concentrations in the early stage of lactation (5.66 and 0.43 mg/kg). Significantly lower concentrations of Fe and higher concentrations of Cd were found in the medium stage (0.23 mg/kg and 1.08 µg/kg) of lactation compared to both the early and late stages of lactation. An analysis of the correlation coefficients between the essential trace and toxic elements in Lacaune sheep milk during lactation determined a significantly positive correlation between Fe:Cr, Fe:Mn, Fe:Co, Fe:Se, Zn:Ni, Zn:Se, Cr:Mn, Cr:Co, Cr:Se, Cr:Mo, Mn:Co, Mn:Pb, Co:Ni, Co:Se, Ni:Se, Se:Mo, Se:Pb, and Cd:Pb. A significantly negative correlation was also found between Cu:Mn, Zn:Mo, Cg:Hg, and Hg:Pb. Based on the obtained results, it is recommended that the influence of the stage of lactation, as well as the breed of sheep, should be included when designing experiments. In general, sheep milk is rich in essential trace elements, but it also contains a very low content of toxic elements, which provides justification for increasing the breeding of Lacaune sheep and indicates the convenience of consuming their milk without risking the consumer's health.

Enhancement of Salinity Stress Tolerance in Lettuce (Lactuca sativa L.) via Foliar Application of Nitric Oxide.

Salt stress negatively affects the growth, development, and yield of horticultural crops. Nitric oxide (NO) is considered a signaling molecule that plays a key role in the plant defense system under salt stress. This study investigated the impact of exogenous application of 0.2 mM of sodium nitroprusside (SNP, an NO donor) on the salt tolerance and physiological and morphological characteristics of lettuce (Lactuca sativa L.) under salt stress (25, 50, 75, and 100 mM). Salt stress caused a marked decrease in growth, yield, carotenoids and photosynthetic pigments in stressed plants as compared to control ones. Results showed that salt stress significantly affected the oxidative compounds (superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX)) and non-oxidative compounds (ascorbic acid, total phenols, malondialdehyde (MDA), proline, and H2O2) in lettuce. Moreover, salt stress decreased nitrogen (N), phosphorous (P), and potassium ions (K+) while increasing Na ions (Na+) in the leaves of lettuce under salt stress. The exogenous application of NO increased ascorbic acid, total phenols, antioxidant enzymes (SOD, POD, CAT, and APX) and MDA content in the leaves of lettuce under salt stress. In addition, the exogenous application of NO decreased H2O2 content in plants under salt stress. Moreover, the exogenous application of NO increased leaf N in control, and leaf P and leaf and root K+ content in all treatments while decreasing leaf Na+ in salt-stressed lettuce plants. These results provide evidence that the exogenous application of NO on lettuce helps mitigate salt stress effects.

Occurrence and Health Risk Assessment of Cadmium Accumulation in Three Tricholoma Mushroom Species Collected from Wild Habitats of Central and Coastal Croatia.

This study deals with the biomonitoring of cadmium (Cd) heavy metal in the three selected Tricholoma mushroom species collected from wild habitats of central and coastal Croatia. For this, mushroom (T. columbetta: n = 38, T. portentosum: n = 35, and T. terreum: n = 34) and surface soil samples were collected from nine forest localities of Croatia and analyzed for Cd concentration using inductively coupled plasma−optical emission spectrometry (ICP−OES) through the acid digestion method. The findings revealed that Cd was present in Tricholoma spp. and surface soil. However, the maximum mean Cd concentration (mg/kg dry weight) was recorded in T. portentosum (cap: 0.98; stipe: 0.72), followed by T. columbetta (cap: 0.96; stipe: 0.73) and T. terreum (cap: 0.81; stipe: 0.63). The bioconcentration factor (BCF) value (>1) revealed that the selected Tricholoma spp. had the potential for Cd accumulation. Moreover, the principal component (PC) and hierarchical cluster (HC) analyses were used to derive the interactions and similarities between Cd levels Tricholoma spp. and sampling localities. The multivariate analysis suggested that central sampling localities had higher Cd levels as compared to coastal localities. However, the daily intake of metals (DIM < 0.426) and health risk index (HRI < 1) showed that there was no potential health risk associated with the consumption of selected Tricholoma spp. The findings of this study are helpful to understand the Cd accumulation behavior of wild edible Tricholoma spp. collected from Croatia.

Risk Assessment of Heavy Metals Occurrence in Two Wild Edible Oyster Mushrooms (Pleurotus spp.) Collected from Rajaji National Park.

This study aimed at assessing the concentration of six heavy metals (Cd, Cr, Cu, Fe, Mn, and Zn) in two wild edible oyster mushrooms (Pleurotus ostreatus and Pleurotus djamor) collected from Rajaji National Park in Haridwar, India. For this purpose, mushroom samples were collected from selected locations (forest, residential, tourist, industrial areas, and transportation activities) from June 2021 to July 2022 and subsequently analyzed for selected heavy metals using atomic absorption spectroscopy (AAS). Results showed that both Pleurotus spp. had significantly varying (p < 0.05) concentrations of heavy metals. However, P. ostreatus showed relatively higher concentration levels of these metals compared to P. djamor. The mean concentrations (mg/kg dry weight) of the Cd, Cr, Cu, Fe, Mn, and Zn in P. ostreatus and P. djamor were 0.10 and 0.08, 0.87 and 0.64, 16.19 and 14.77, 28.49 and 27.15, 9.93 and 8.73, and 18.15 and 15.76, respectively. As indicated by the multivariate analysis tools i.e., principal component analysis (PCA) and hierarchical cluster analysis (HCA), the locations near the residential, industrial, and transportation activities had higher concentration levels of heavy metals. Moreover, the health risk studies using the target hazard quotient (THQ < 1) showed no significant health risk as the consumption of both Pleurotus spp., except for at one location, had high-traffic activities. The findings of this study provide vital information about the occurrence of potentially toxic heavy metals in wild edible Pleurotus spp. in Rajaji National Park in Haridwar, India representing a safeguard for mushroom consumers.

Spatial Assessment of Potentially Toxic Elements (PTE) Concentration in Agaricus bisporus Mushroom Collected from Local Vegetable Markets of Uttarakhand State, India.

This study presents a spatial assessment of eight potentially toxic elements (PTE: Cd, Cr, Cu, Fe, Pb, Ni, Mn, and Zn) in white button (Agaricus bisporus J.E. Lange) mushroom samples collected from the local vegetable markets of Uttarakhand State, India. Fresh A. bisporus samples were collected from thirteen districts and fifteen sampling locations (M1-M15) and analyzed for the concentration of these PTE using atomic absorption spectroscopy (AAS). The results revealed that A. bisporus contained all eight selected PTE in all sampling locations. Based on the inverse distance weighted (IDW) interpolation, principal component (PC), and hierarchical cluster (HC) analyses, the areas with a plane geographical distribution showed the highest PTE concentrations in the A. bisporus samples as compared to those in hilly areas. Overall, the decreasing order of PTE concentration in A. bisporus was recognized as Fe > Zn > Mn > Cr > Cu > Ni > Cd > Pb. The Kruskal−Wallis ANOVA tests displayed a highly significant (p < 0.05) difference among the sampling locations. However, the concentration of PTE was below permissible limits, indicating no potential hazard in consuming the A. bisporus. Similarly, the health risk assessment studies using the target hazard quotient (THQ) also showed no significant health risk associated with the consumption of A. bisporus being sold in the local mushroom markets of Uttarakhand, India. This study is the first report on state-level monitoring of PTE in A. bisporus mushrooms, which provides crucial information regarding the monitoring and occurrence of potentially toxic metallic elements.

Sustainable Use of Sewage Sludge as a Casing Material for Button Mushroom (Agaricus bisporus) Cultivation: Experimental and Prediction Modeling Studies for Uptake of Metal Elements.

The present study focused on the use of sewage sludge (SS) as a casing material amendment and the potential uptake of metal elements by the cultivated white button (Agaricus bisporus: MS-39) mushroom. Laboratory experiments were performed under controlled environmental conditions to grow A. bisporus on the composted wheat straw substrate for 50 days. Different treatments (0, 50, 100, 150, and 200 g/kg) of casing material were prepared by mixing garden and dried SS and applied on the mushroom substrate after proper sterilization. The results revealed that SS application was significant (p < 0.05) in accelerating mushroom yield with a biological efficiency of 65.02% for the mixing rate of 200 g/kg. Moreover, the maximum bioaccumulation of selected metal elements (Cu, Cr, Cd, Fe, Mn, and Zn) was observed using the same treatment. Additionally, the multiple regression models constructed for the uptake prediction of metal elements showed an acceptable coefficient of determination (R2 > 0.9900), high model efficiency (ME > 0.98), and low root mean square error (RMSE < 0.410) values, respectively. The findings of this study represent sustainable use of SS for the formulation of mushroom casing material contributing toward synergistic agro-economy generation and waste management.

The Impact of Age at First Lambing on Milk Yield and Lactation Length in a Population of Istrian Sheep under Semi-Intensive Management.

This study aimed to examine the impact of ewe's age at first lambing (AFL) on days in milk (DIM), average daily milk yield (DMY), and total milk yield (TMY). Symmetrical bimodal distribution of AFL enabled classification of maidens in those mated in the first (47%) or second year of life (53%). After accounting for all available sources of phenotypic variability with the linear mixed model for repeated records, it was estimated that AFL had a statistically significant effect only on DIM (p < 0.001). The litter size had a significant effect only on TMY (p < 0.001), while the effect of the parity was significant for all the examined traits (p < 0.001). The results of the study suggest that prolongation of age at first mating to the second year of life is not justified in dairy-orientated sheep farms. However, more evidence on this issue is needed for generalization, especially considering some other traits that can impact profitability of dual-purpose sheep farms (reproduction traits, growth rate of lambs, etc.).

Contamination, bioconcentration and distribution of mercury in Tricholoma spp. mushrooms from southern and northern regions of Europe.

The contamination, bio-concentration and distribution of mercury (Hg) in wild mushrooms of the genus Tricholoma such as T. equestre, T. portentosum, T. columbeta, and T. terreum were studied, and the possible dietary intake and risk for human consumers in Europe was estimated. Mushrooms, together with the associated forest topsoils were collected from 10 unpolluted and geographically distant areas, far from local or regional emission sources, in Poland (2 sites) and Croatia (8 sites). The Hg contents were in the range 0.10 ± 0.06 to 0.71 ± 0.34 mg kg-1 dry matter in caps and 0.04 ± 0.02 to 0.38 ± 0.13 mg kg-1 in stems. The corresponding topsoil concentrations varied over a relatively narrow range between sites, from 0.013 ± 0.003 to 0.028 ± 0.006 mg kg-1 dry matter. Overall, the study results showed low levels of mercury both, in edible Tricholoma mushrooms and forest topsoils from background (unpolluted) forested areas in Croatia and Poland. The morphological distribution showed considerably greater concentrations of mercury in the caps relative to the stems with ratios ranging from 1.6 ± 0.6 to 3.9 ± 1.8. T. equestre showed good ability to bioconcentrate Hg, with bioconcentration factors (BCF) values in the range 18 ± 7 to 37 ± 18. The data suggests that Tricholoma mushrooms from unpolluted areas in southern and northern regions of Europe can be considered as a low risk food from the point of view of the tolerable Hg intake.

Drip loss assessment by EZ and bag methods and their relationship with pH value and color in mutton.

Drip loss, pH value, and color are among the important traits that determine meat quality. Contrary to pH and color, the method associated with drip loss is not yet standardized, and literature data are difficult to compare. Besides, to our knowledge, there is no research comparing drip loss methods and their relation with pH and color in mutton. This study aimed to assess drip loss measurements in mutton taken by different methods (EZ and bag - BM) and their relationship with pH values and color. Mutton samples (Musculus longissimus thoracis et lumborum) originating from 20 ewes of Istrian sheep were used to examine the effect of the method on drip loss after 24 h (EZ 24 vs. BM 24 ) and 48 h (EZ 48 vs. BM 48 ). Furthermore, correlations between drip loss, pH value, and color were analyzed. The statistical analysis was conducted in R programming environment by using different packages. Within the EZ method there was no significant difference ( p > 0.05 ) between ventral and dorsal sample cores used for the assessment of EZ drip loss. Drip loss measured with the same method at two different points of time (24 and 48 h) differed significantly ( p < 0.001 ). There was also a significant difference in drip loss determined by different methods (EZ vs. BM) at the same point of time. There were significant ( p < 0.05 ) correlations between pH 45 min and all color parameters ( L * 4 , a * , b * ). The L * , a * , and b * parameters were highly correlated ( p < 0.001 ). The strongest correlation occurred between a * and b * parameter ( r = 0.93 ). Correlations between drip loss by EZ method and other meat quality attributes were low and not significant. The b * parameter correlated with BM 24 ( r = 0.46 ) and BM 48 ( r = 0.58 ), while a * correlated only with BM 48 ( r = 0.50 ). The correlations between the EZ 24 and BM 24 as well as between the EZ 48 and BM 48 were both non-significant ( p > 0.05 ). Drip loss cannot be predicted with sufficient accuracy by using pH and color. EZ and BM method in mutton do not provide equivalent results for measuring drip loss. Comparisons of the results obtained with different methods should be avoided or at least performed with great precaution.

Concentrations of mercury and other elements in ewes' milk: Effect of lactation stage.

There is an increased production and demand for ewes' milk in the Republic of Croatia, as well as globally. There is also a growing concern about its quality, since milk from farm animals may become contaminated with mercury and other toxic elements. Thus, the aim of this paper is to determine the influence of lactation stage on the ewes' milk quality in western Croatia by considering concentrations of mercury and other elements in ewes' milk. The research was conducted on 36 Travnik pramenka sheep during different lactation stages. The digested milk samples were analysed with continuous flow hydride generation technique by using inductively coupled plasma mass spectrometry. Samples were taken during 40th, 80th and 120th d of lactation. Yield and quality of ewes' milk was within lactation curve. As lactation progressed, significantly lower concentrations of Hg (on 80th d compared to 40th d) and of Cd (120th d compared to 80th d) were noted, and Hg on 120th d was below the detection limit. Concentrations of Ca and Cu were lower on the 120th d compared to 40th d, while P, Mg, Fe, Zn, Mn, and Se were lower on the 80th and 120th d compared to the 40th d. Concentrations of K, Mo, and Cr differed among all stages of lactation. Regarding toxic elements, the observed low concentrations of Hg, Co, Cd and As suggest that ewes' milk in western Croatia is safe for human or animal consumption.

137Cs in mushrooms from Croatia sampled 15-30 years after Chernobyl.

The aim of this study was to select species with higher potential to accumulate 137Cs among the available mushroom species, by determining the activity concentrations of 137Cs in mushrooms collected along north and north-western part of Croatia. A total of 55 samples of 14 different species were analyzed and the potential of mycorrhizal and saprotrophic species to accumulate 137Cs was compared. A wide range of the dry weight activity concentrations of 137Cs was detected, ranging from 0.95 to 1210 Bq/kg (154 Bq/kg mean value; 52.3 Bq/kg geometric mean) in mycorrhizal and 1.05-36.8 Bq/kg (8.90 Bq/kg mean value; 5.49 Bq/kg geometric mean) in saprotrophic species. Statistical analyses showed that mycorrhizal species accumulate significantly higher concentrations of 137Cs and thus could perform better as long-term bioindicators of environmental pollution by radiocaesium then saprotrophic species. The comparison of Boletus sp. and Hydnum repandum (both mycorrhizal species commonly found in Croatia) showed, in general order of magnitude, higher accumulation in Hydnum repandum. Clearly, mushrooms, especially mycorrhizal species, can be used as significant indicators even decades after the occurrence of any serious 137Cs contamination event. However, as a wide range of values indicates that various parameters may influence the total uptake of the 137Cs into the mushroom fruit bodies, it is necessary to emphasize that 137Cs activity detected in a single mushroom sample is very site-specific.

Heavy metal bioaccumulation by wild edible saprophytic and ectomycorrhizal mushrooms.

Heavy metals cause serious problems in the environment, and they can be accumulated in organisms, especially in the higher fungi. The concentration of Ni, Cr, Pb, Cd, and Hg in 10 species of edible mushrooms in Medvednica Nature Park, Croatia was therefore determined. In addition, the similarity between the studied species was determined by cluster analysis based on concentrations of the aforementioned metals in the fruiting bodies. The contents of nickel, chromium, lead, cadmium, and mercury in the fruiting bodies of mushrooms were obtained by X-ray fluorescence spectrometry. The highest concentrations of Ni (3.62 mg kg(-1)), Cr (3.01 mg kg(-1)), and Cd (2.67 mg kg(-1)) were determined in Agaricus campestris. The highest concentration of Pb (1.67 mg kg(-1)) was determined in Macrolepiota procera, and the highest concentration of Hg (2.39 mg kg(-1)) was determined in Boletus edulis. The concentration of all heavy metals significantly differed (p < 0.001) between examined saprophytic and ectomycorrhizal mushrooms. Considering anatomical part of the fruiting body (cap-stipe), a considerably higher concentration of the analyzed elements was found in the cap for all mushroom species. According to calculated bioconcentration factors, all the examined species were found to be bioexclusors of Ni, Cr, and Pb and bioaccumulators of Cd and Hg. Cluster analysis performed on the basis of the accumulation of the studied metals revealed great phenotypic similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation.