Art16_Bratek.indd Journal of Applied Botany and Food Quality 85, 100 - 104 (2012) 1Department of Plant Physiology and Molecular Plant Biology, Eötvös Loránd University, Budapest, Hungary 2 Department of Botany, Faculty of Veterinary Science, Szent István University, Budapest, Hungary 3Vác, Hungary Mineral composition of hypogeous fungi in Hungary Á.K. Orczán1, J. Vetter2, Z. Merényi1, É. Bonifert3, Z. Bratek1* (Received October 20, 2011) * Corresponding author Introduction In the course of the work, 93 samples from 17 hypogeous fungus species belonging to 6 genera were taken from various habitats in Hungary and were analysed for the concentrations of 22 elements using the inductively coupled plasma spectroscopy ICP method. All the measurements were made in three independent replications. The data were compared with the element contents of 625 epigeous fungi, previously determined using the same method. For all the genera, the elements present in the highest concentrations on a dry matter basis were potassium (6990-29590 ppm) and phosphorus (3400-9140 ppm). These were followed by the macroelements calcium (330-2190 ppm), magnesium (810-1000 ppm) and sodium (110-2990), and the microelements aluminium (30-450 ppm), zinc (60-340 ppm), iron (30-120 ppm) and copper (25-75 ppm), in different orders for each genus. Until now the element contents of fungi have mostly been analysed to determine the nutritional value of edible fungi, and the data on other elements for instance total minerals are insuffi cient for further comparisons (MATTILA et al., 2001). Very little work has been published on the mineral contents of hypogeous large fungi, despite the fact that these include commer- cially important species such as Tuber aestivum and T. melano- sporum (IAN et al., 2003). Most of the previous papers exhibited the following characteristics: (1) some species (e.g. Terfezia species, Tuber melanosporum) were investigated more frequently, and others rarely, if at all; (2) the analyses concentrated chiefl y on toxicological and/or environmental aspects; (3) measurements were only made on a few elements (important from the nutritional point of view); (4) only cultivated fungi were included in the studies. The aim of the present work was to determine the element contents of various species of hypogeous fungi in order to answer the following questions: (1) Which characteristic differences can be observed between the element contents of hypogeous and epigeous fungi? (2) Which differences characterise the element contents of various genera of hypogeous fungi? (3) Is there any signifi cant difference between the element contents of hypogeous Ascomycota and Basidiomycota genera? (4) Can any signifi cant difference be observed between the element contents of edible and non-edible hypogeous fungi? Materials and methods A total of 93 hypogeous fungus samples were collected from habitats covering the whole area of Hungary, and were shown by macro- and microscopic analysis to represent 17 species belonging to 6 genera. The species names and number of samples are listed in Tab. 1. After cleaning and drying, the fruit bodies were ground. The samples (200 mg of fungi powder) were digested in closed Tefl on bombs in triplicate (2 cm3 HNO3 + 2 cm3 H2O2 /30%/) at 1.56×105 Pa pressure for 20 min. The digested materials were fi ltered and diluted to 10 cm3, after which the mineral element contents were determined by inductively coupled plasma spectroscopy. The data were evaluated using the GraphPad InStat program (version 3.00, 32 bit for Win 95/NT, GraphPad Software, San Diego, California, USA, www.graphpad.com) and the Kolmogorov-Smirnov test was used to determine the normality of the data. For data with normal distribution, one-way ANOVA was carried out using the Bonferroni post hoc test and the D (Welch) test, while in the case of non-normal distribution the Kruskall-Wallis test was applied, using Dunnett’s post test (DUNN, 1964) to identify signifi cant differences. Results and discussion The results obtained for the ICP analysis of 22 elements are presented in Tab. 2 for the six hypogeous fungus genera (Elaphomyces, Gautieria, Mattirolomyces, Melanogaster, Rhizopogon, Tuber) in comparison with a database containing data on 625 samples of epigeous fungi (VETTER, 2003). By comparing the mean quantities of each element, three groups of elements could be distinguished, as illustrated in Tab. 3. As can be seen in the Tab. 3, the fruit bodies of the two fungal groups had very similar mean contents of aluminium, boron, copper, strontium and titanium, while hypogeous fungi generally contained larger quantities of barium, calcium, molybdenum, sodium and zinc. On the other hand, the fruit bodies of hypogeous species had lower mean contents of arsenic, cadmium, cobalt, chromium, iron, potassium, magnesium, manganese, nickel, phosphorus, selenium and vanadium. Three of the macroelements (potassium, magnesium and phosphorus) were thus found in this group. The higher mean contents of arsenic, cadmium, selenium and vanadium in epigeous Tab. 1: Species names and number of the samples Species name: Number of samples: Elaphomyces aculeatus Vittad. 6 Elaphomyces granulatus Fries 2 Elaphomyces muricatus Fries 33 Elaphomyces persoonii Vittad. 1 Elaphomyces reticulatus Vittad. 2 Elaphomyces virgatosporus Hollós 6 Gautieria borealis States, Fogel & Hosford 3 Mattirolomyces terfezioides (Mattir.), E. Fisch 2 Melanogaster ambiguus (Vittad.) Tulasne & C. Tulasne 2 Rhizopogon roseolus (Corda) Th. M. Fries 3 Rhizopogon vulgaris var. intermedius Svrcek 10 Tuber aestivum Vittad. 11 Tuber brumale Vittad. 1 Tuber excavatum Vittad. 4 Tuber ferrugineum Vittad. 1 Tuber mesentericum Vittad. 3 Tuber rapaeodorum Tul. 3 Mineral composition of hypogeous fungi in Hungary 101 fungi can be explained by the fact that many fungal taxa, such as the Amanita genus, are known to accumulate these elements (VETTER, 2005). GIACCIO et al., 1992 detected that copper and cadmium might be accumulated in the 7 studied truffl e species, zinc appeared to be accumulated only in a certain range, while other examined elements did not seem to be accumulated. GRANETTI et al., 2005 also detected copper, cadmium and zinc accumulation in T. melanosporum. MASER et al., 2008 found high phosphorus and potassium, while low sodium and calcium content in fruit bodies, especially in comparison with eggs, milk and vegetables. Potassium, sodium and calcium as well as other micronutrients, however, could vary markedly among and within species, but in general, fruit bodies were particularly rich in manganese, copper and zinc. Based on the complete database of the present studies in case of hypogeous species the difference between the minimum and maximum concentration of each element was smallest for phos- phorus (8x) and magnesium (9x) and greatest for molybdenum (1780x), arsenic (835x) and boron (940x). In case of epigeous fungi the ranges were wider. The smallest difference was found for magnesium (13x) and the greatest for boron (3300x). It could also be seen that the most important elements (potassium, phosphorus, calcium, magnesium) were among those with the smallest coeffi cient of variation in the fruit bodies of both fungal groups. When the deviation values were compared between genera it was observed that sodium was generally among the elements exhibiting the greatest deviation, with the exception of the Elaphomyces genus, where it had the smallest deviation in both relative and absolute terms. Of the four major elements, the deviation for calcium was the greatest in all the genera except Rhizopogon, where it was almost the smallest. Averaged data groups are presented in Tab. 4 for the six hypogeous fungus genera to which most of the samples belonged (Elapho- myces, Tuber, Rhizopogon, Gautieria, Mattirolomyces, Melano- gaster), together with the databases of the epigeous fungi used for comparative purposes. The potassium contents of all the hypogeous fungal genera proved to be lower than that in epigeous fungi that tend to concentrate potassium 20-40-fold in fruit bodies (SEEGER, 1978), but were the highest amounts in all hypogeous genera. GRANETTI et al., 2005 also showed potassium to be the highest content element in T. melanosporum. The lowest value of potassium (6994 ppm) was recorded for the Elaphomyces genus, which was very low even compared with the other hypogeous genera. The opposite tendency was observed for sodium, an element of great importance from the biological point of view, as the sodium contents of the hypogeous fungi were higher than those measured in epigeous fungi, particularly in the case of Elaphomyces. The only exception was the Tuber genus, where the sodium content was approximately Tuber genus, where the sodium content was approximately Tuber the same as in epigeous fungi, and Mattirolomyces, which exhibited a value of only 111 ppm, far lower than the mean Na content of epigeous fungi and even lower than the aluminium content of this genus. In the case of calcium the average content was higher in hypogeous fungi, but this was principally due to the high values for Tuber and Tuber and Tuber Melanogaster, as the calcium contents of the other genera were similar to the average for epigeous fungi. In fact, that of Gautieria was extremely low (330 ppm). The mean phosphorus content of the hypogeous fungi (5625 ppm) was well below the level recorded for epigeous fungi (7800 ppm). The phosphorus content of the Tuber genus hardly surpassed the epigeous mean (7810 ppm), while that of Mattirolomyces was far higher (9140 ppm). In the case of magnesium, which content depends on species and genus (SEEGER and MANFRED, 1979), none of the hypogeous genera had contents as high as the mean for the epigeous fungi (1440 ppm), with an average level of 870 ppm. It is interesting to note that the calcium: phosphorus and potassium:sodium ratios were also very different for the various genera. Among the biologically important microelements, no signifi cant differences could be detected in the contents of copper and boron. When the data series for the hypogeous fungi were analysed at the genus level (Tab. 4), it could be seen that, despite the similarity of the means, samples from the Gautieria, Mattirolomyces and Melanogaster genera had very low, hardly detectable contents Melanogaster genera had very low, hardly detectable contents Melanogaster of boron. The average quantity of manganese (17 ppm) in the hypogeous fungi was considerably lower than the mean value for the comparative database (40 ppm), yet the two data available for the Melanogaster genus averaged 300 ppm! A comparison of the mean contents of zinc indicated that the hypogeous fungi contained considerably more of this element (260 ppm) than their epigeous counterparts (115 ppm). When the genera were evaluated separately it could be clearly seen that the Elaphomyces genus, which was Tab. 2: Average element concentration of hypogeous and epigeous fungi with standard deviation Average of Average ofAverage ofA Elements 97 hypogeous materials 625 epigeous materials (ppm) (ppm) Al 150 ± 140 150 ± 217 As 4 ± 12 9 ± 15 B 13 ± 18 16 ± 45 Ba 8 ± 8 5 ± 5 Ca 1770 ± 1900 1460 ± 1270 Cd 2 ± 4 3 ± 7 Co 1 ± 1 1 ± 1 Cr 2 ± 1 3, ± 9 Cu 60 ± 40 60 ± 50 Fe 100 ± 80 240 ± 300 K 14800± 10500 34900 ± 14800 Mg 870 ± 300 1440 ± 640 Mn 17 ± 57 43 ± 45 Mo 2 ± 12 0,7 ± 0,6 Na 1880 ± 1600 325 ± 380 Ni 2 ± 2 4 ± 6 P 5625 ± 2625 7800 ± 4300 Se 0,3 ± 0,8 5 ± 4 Sr 5 ± 3 5 ± 5 Ti 2 ± 5 3 ± 3 V 0,4 ± 0,4 2 ± 14 Zn 260 ± 160 115 ± 110 Total 25600 46558,00 Tab. 3: Grouping of elements based on their mean concentrations in hypo- geous and epigeous fungi Mean element concentration Elements Nearly identical Al, B, Cu, Sr, Ti Hypogeous species > epigeous species Ba, Ca, Mo, Na, Zn Hypogeous species < epigeous species As, Cd, Co, Cr, Fe, K, Mg, Mn, Ni, P, Se, V 102 Á.K. Orczán, J. Vetter, Z. Merényi, É. Bonifert, Z. Bratek represented by a large number of samples, had the highest zinc concentration (340 ppm), while that of Gautieria and Melanogaster was much lower (around 60 ppm). Among the elements of interest from the toxicological point of view, the arsenic content was below the mean value recorded for the epigeous fungi, with the exception of the Gautieria genus, though it must not be forgotten that the relatively high average value (9 ppm) for epigeous fruit bodies was infl uenced by the presence of several accumulator genera (particularly species belonging to the Agaricus and Macrolepiota genera). This was also true of the concentrations of cadmium and chromium. SEEGER (1978a) found highly scattered values of cadmium content in 402 epigeous fungi, and demonstrated that it was clearly species-dependent, and to a lesser extent genus- dependent. The quantity of nickel was also lower in the hypogeous fungus group (1,9-3,6 ppm), though samples from the Gautieria genus had a surprisingly high content (14,7 ppm). The concentrations of selenium and vanadium must be viewed with similar reservations. In both cases the hypogeous fungi had very low values (in many cases below the detection limit) compared with most of the epigeous fungi, but here again the very high values recorded for a number of accumulating taxa (Boletus species in the case of selenium and Amanita muscaria for vanadium) were responsible for the higher average values for this fungal group. In terms of the total mineral elements (Tab. 2 and 5), considerable differences were observed, as the total element content of the hypogeous fungi (25 ppm) was substantially less than that of fungi with epigeous fruit bodies (45 ppm). The analysis of individual genera revealed that the mineral contents of Tuber and Tuber and Tuber Mattirolomyces were closest to those of the group used for comparison. In Tab. 5 the hypogeous fungi were divided according to their taxonomic groupings into Ascomycota (76 samples) and Basi- diomycota species (21 samples). When the data for these groups were compared the following differences were found: a. Both taxonomic groups of hypogeous fungi contained ap- proximately equal quantities of the elements B, Ba, Ca, Fe, Cr, Cu, Mg, P and Sr; b. The element content of the Ascomycota group was greater than that of the Basidiomycota group in the case of Al, Na, Ti, V and Zn; c. The Basidiomycota had higher concentrations of As, Cd, Co, K, Mn, Mo, Ni and Se. A comparison of the total element quantities showed that hypogeous fungi belonging to the Basidiomycota had considerably higher element contents than the Ascomycota, mainly due to the great difference in the potassium concentrations. It should be noted, however, that the Ascomycota contained more zinc. The hypogeous fungi were also grouped on the basis of edibility (Tab. 6), with 14 samples in the edible group and the majority (83) being inedible. The two groups exhibited a number of substantial differences, with higher quantities of boron, calcium, copper and magnesium, much higher contents of potassium and phosphorus, and lower quantities of zinc, manganese and sodium in the edible species. All in all, these fungi contained an average of 38580 ppm mineral elements, as compared with 23370 ppm in the inedible group. Tab. 4: Average element concentration of six hypogeous fungi taxa and epigeous fungi with standard deviation Elements Average of Average of Average of Average of Average of Average of Average of 50 Elaphomyces 3 Gautieria 2 Mattirolomyces 2 Melanogaster 13 Rhizopogon 23 Tuber 625 epigeous materials materials materials materials materials materials fungi materials (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) (ppm) Al 175 ± 120 30 ± 3 450 ± 480 250 ± 210 70 ± 40 130 ± 160 150 ± 210 As 3 ± 10 20 ± 5 0,1 ± 0,0 4 ± 5 7 ± 25 0,1 ± 0,0 9 ± 15 B 12 ± 15 0,1 ± 0,0 0,1 ± 0,0 6 ± 8 13 ± 25 15 ± 20 15 ± 45 Ba 9 ± 75 2 ± 0,0 3 ± 0,5 15 ± 1 9 ± 10 5 ± 3 4 ± 5 Ca 1455 ± 2030 330 ± 130 1260 ± 330 2190 ± 1300 1570 ± 730 2170 ± 1250 1460 ± 1270 Cd 1 ± 45 1 ± 0,2 0,6 ± 0,0 0,1 ± 0,0 3 ± 6 3 ± 2 3 ± 7 Co 0,5 ± 0,65 4 ± 2 0,1 ± 0,0 0,3 ± 0,2 1 ± 1 0,2 ± 0,4 1 ± 1 Cr 1,3 ± 1 4 ± 0,3 2 ± 0 0,6 ± 0,6 1 ± 1 1 ± 0,5 3 ± 9 Cu 50 ± 20 25 ± 3 80 ± 60 35 ± 15 50 ± 70 65 ± 35 60 ± 50 Fe 100 ± 65 32,20 ± 3 55 ± 6 75 ± 5 120 ± 95 110 ± 110 240 ± 305 K 6990 ± 4590 18400 ± 1400 29585 ± 210 17295 ± 8000 23395 ± 13750 24110 ± 4245 34865 ± 14760 Mg 820 ± 335 890 ± 80 1000 ± 50 810 ± 320 830 ± 390 955 ± 210 1440 ± 640 Mn 8 ± 7 20 ± 5 10 ± 0 305 ± 365 13 ± 15 10 ± 7 45 ± 45 Mo 0,2 ± 0,1 0,1 ± 0,0 0,2 ± 0,1 0,5 ± 0,5 10 ± 35 0,2 ± 0,2 0,7 ± 0,6 Na 2990 ± 995 420 ± 170 110 ± 2,76 570 ± 505 870 ± 440 330 ± 280 325 ± 385 Ni 1 ± 1 15 ± 1 1 ± 0,4 1 ± 0,2 2 ± 2 1 ± 0,5 3 ± 6 P 4515 ± 2090 4970 ± 455 9140 ± 460 3405 ± 150 6030 ± 3410 7810 ± 2015 7800 ± 4320 Se 0,2 ± 0,6 0,1 ± 0,0 0,1 ± 0,0 0,1 ± 0,0 1 ± 1 0,1 ± 0,0 5 ± 4 Sr 3 ± 2 2, ± 1 5 ± 3,30 7 ± 4 4 ± 2 7 ± 4 5 ± 5 Ti 2 ± 1 0,2 ± 0,2 0,4 ± 0,1 1 ± 0,2 0,8 ± 0,5 4 ± 10 3 ± 3 V 1 ± 1 0,1 ± 0,0 0,2 ± 0,1 0,5 ± 0,5 0,2 ± 0,1 0,3 ± 0,2 2 ± 14 Zn 340 ± 130 60 ± 10 90 ± 1 55 ± 15 135 ± 105 190 ± 65 115 ± 110 Total 17480 25225 41800 25015 33145 35915 46560 Mineral composition of hypogeous fungi in Hungary 103 Tab. 5: Average element concentration of hypogeous ascomycetes and basidiomycetes and epigeous fungi with standard deviation Elements Average of Average of Average of 76 ascomycetes materials 21 basidiomycetes materials 625 epigeous fungi materials (ppm) (ppm) (ppm) Al 170 ± 150 85 ± 80 150 ± 220 As 2 ± 10 7± 20 9 ± 15 B 13 ± 18 12 ± 20 16 ± 45 Ba 8 ± 6 10 ± 10 5 ± 5 Ca 1770 ± 2000 1760 ± 1490 1470 ± 1270 Cd 2 ± 3 3 ± 5 3 ± 7 Co 0,4 ± 0,5 1 ± 1 1 ± 2 Cr 1 ± 0,8 2 ± 2 3 ± 9 Fe 100 ± 80 100 ± 85 200 ± 300 Cu 60 ± 30 50 ± 60 60 ± 50 K 13000 ± 9400 21600 ± 12000 34900 ± 14800 Mg 900 ± 300 845 ± 320 1400 ± 600 Mn 9 ± 7 50 ± 120 40 ± 45 Mo 0,2 ± 0,2 6 ± 30 0,7 ± 0,6 Na 2100 ± 1500 1100 ± 1750 325 ± 380 Ni 1,0 ± 0,7 4 ± 4 4 ± 6 P 5680 ± 2600 5400 ± 2800 7800 ± 4320 Se 0,1 ± 0,5 0,7 ± 1 5 ± 5 Sr 5 ± 3 4, ± 2 5 ± 5 Ti 2 ± 6 0,8 ± 0,5 3 ± 4 V 0,4 ± 0,4 0,2 ± 0,2 2 ± 14 Zn 300 ± 150 120 ± 90 115 ± 110 Total 24000 31200 45700 Tab. 6: Average element concentration of edible (Tuber aestivum, Tuber brumale, Mattirolomyces terfezioides) and non-edible hypogeous and epigeous fungi with standard deviation Elements Average of Average of Average of 14 edible hypogeous fungi materials 83 non-edible hypogeous fungi materials 625 epigeous fungi materials (ppm) (ppm) (ppm) Al 225 ± 250 140 ± 110 150 ± 220 As 0,1 ± 0,0 4 ± 13 9 ± 15 B 15 ± 18 10 ± 18 15 ± 45 Ba 6 ± 3 9 ± 8 5 ± 5 Ca 2535 ± 1200 1600 ± 1970 1500 ± 1270 Cd 3 ± 2 2 ± 4 3 ± 7 Co 0,1 ± 0,0 1 ± 1 1 ± 1 Cr 1 ± 0,4 2 ± 1 3 ± 9 Cu 75 ± 40 50 ± 40 60 ± 50 Fe 125 ± 120 100 ± 70 240 ± 300 K 25800 ± 2700 13000 ± 10200 34865 ± 14760 Mg 1000 ± 200 840 ± 310 1440 ± 640 Mn 10 ± 7 20 ± 60 40 ± 45 Mo 0,2 ± 0,2 2 ± 10 0,7 ± 0,6 Na 240 ± 200 2200 ± 1600 325 ± 380 Ni 1 ± 0,5 2 ± 2 4 ± 6 P 8300 ± 1700 5200 ± 2480 7800 ± 4320 Se 0,1 ± 0,0 0,3 ± 1 5 ± 5 Sr 8 ± 3 4 ± 3 5 ± 5 Ti 2 ± 3 2 ± 6 3 ± 3 V 0,1 ± 0,1 0,5 ± 0,4 2 ± 14 Zn 170 ± 60 270 ± 165 115 ± 110 Total 38582,27 23460 46590 104 Á.K. Orczán, J. Vetter, Z. Merényi, É. Bonifert, Z. Bratek Conclusion In our work we got a comprehensive view of the element content of several hypogeous fungi genera. Compared to the epigeous fungi we found higher element content in the hypogeous fungi. The main general difference was in the potassium level, however that was the highest of all the hypogeous genera and the epigeous fungi of the investigated elements. The most important elements (potassium, phosphorus, calcium, magnesium) in both groups belong to elements with the smallest coeffi cient of variation. We found signifi cant difference in the studied questions, although the content of elements is strongly dependent on genera and species. Acknowledgements The authors would like to express their grateful thanks to József Garay, of the Department of Plant Taxonomy and Ecology, Eötvös Loránd University (ELTE), Budapest for his help with the statistical analyses, and to Szabolcs Rudnóy and Gabriella Tamaskó, of the Department of Plant Physiology and Molecular Plant Biology, ELTE, Budapest and to Hanna Dóra Orczán for their constant support. This research was funded by a grants from the Hungarian Ministry of Education (No. OM-00055/2006 and OM-00-312/2008). References GIACCIO, M., DI GIACOMO, F., MARCHEGIANI, R., 1992: Chromium, Man- ganese, Nickel, Cooper, Zinc, Cadmium and Lead content in some species off truffl es. Micologia e Vegetazione Mediterranea, VII(2): 287-294. GRANETTI, B., ANGELIS, A., MATEROZZI, G., 2005: Umbria terra di tartufi, Gruppo Micologico Ternano, Terni, Composizione chimica e valore nutritivo del tartufo, 76-78. 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VETTER, J., 2003: Monograph of the mineral composition of basidiomes of higher fungi (In Hungarian). A fi nal report of the research program OTKA (Hungarian Scientifi c Research Foundation) No. 31702. Manuscript, Budapest, 1-99. VETTER, J., 2005: Mineral composition of basidiomes of Amanita species. Mycological Research 109, 746-750. Address of the author: Z. Bratek (corresponding author), E-mail: bratek@caesar.elte.hu