Yuan-Zhong Wang

A mini-review of chemical composition and nutritional value of edible wild-grown mushroom from China.

In China, many species of edible wild-grown mushrooms are appreciated as food and also found use in traditional Chinese medicine. In this mini-review, for the first time, is summarized and discussed data available on chemical components of nutritional significance for wild-grown mushrooms collected from China. We aimed to update and discuss the latest data published on ash, fat, carbohydrates, fibre, proteins, essential amino acids and nonessential amino acids, some essential (P, K, Na, Ca, Mg, Fe, Mn, Zn, Cu) and toxic elements (As, Hg, Cd, Pb), vitamins (thiamine, riboflavin, niacin, tocopherol, vitamin D), flavour and taste compounds, antioxidants and also on less studied organic compounds (lectin, adustin, ribonuclease and nicotine) contents of wild-grown mushrooms.

Mycology, cultivation, traditional uses, phytochemistry and pharmacology of Wolfiporia cocos (Schwein.) Ryvarden et Gilb.: A review

ETHNOPHARMACOLOGICAL RELEVANCE Wolfiporia cocos (Schwein.) Ryvarden et Gilb. has a long history as a Chinese traditional medicine with uses of inducing diuresis, excreting dampness, invigorating the spleen, and tranquilizing the mind. Recently, Wolfiporia cocos has received increasing interest, and phytochemical and pharmacological studies have validated the traditional uses of this species. AIMS OF THE REVIEW To provide an up-to-date and comprehensive overview of the mycology, cultivation, traditional uses, chemical constituents and pharmacological activities aspects of Wolfiporia cocos in order to highlight its ethnopharmacological use and to explore its therapeutic potentials and to provide a basis for future research. MATERIALS AND METHODS The accessible literature, from 1980 to 2012, on Wolfiporia cocos written in English, Chinese, French, Korean, Spanish and Turkish were selected and analyzed. RESULTS The phytochemical and modern pharmacological studies demonstrated that Wolfiporia cocos possess a wide spectrum of pharmacological activities, such as anti-tumor, anti-oxidant, anti-rejection, nematicidal, anti-hyperglycemic, antibacterial, anti-inflammatory and anti-hypertonic stress activities, which could be explained by the presence of various triterpenes and polysaccharides. CONCLUSIONS Modern phytochemical and pharmacological investigations showed that major active components separated from Wolfiporia cocos had anti-tumor, anti-oxidant, anti-rejection activities, and so on. Further investigations are needed to explore the relationship of the molecular mass, chain stiffness, and water solubility of polysaccharide from Wolfiporia cocos with the antitumor activities.

Evaluation of the mercury contamination in mushrooms of genus Leccinum from two different regions of the world: Accumulation, distribution and probable dietary intake.

This study focused on investigation of the accumulation and distribution of mercury (Hg) in mushrooms of the genus Leccinum that emerged on soils of totally different geochemical bedrock composition. Hg in 6 species from geographically diverse regions of the mercuriferous belt areas in Yunnan of SW China, and 8 species from the non-mercuriferous regions of Poland in Europe was measured. Also assessed was the probable dietary intake of Hg from consumption of Leccinum spp., which are traditional organic food items in SW China and Poland. The results showed that L. chromapes, L. extremiorientale, L. griseum and L. rugosicepes are good accumulators of Hg and the sequestered Hg in caps were up to 4.8, 3.5, 3.6 and 4.7 mg Hg kg(-1) dry matter respectively. Leccinum mushrooms from Poland also efficiently accumulated Hg with their average Hg content being an order of magnitude lower due to low concentrations of Hg in forest topsoil of Poland compared to the elevated contents in Yunnan. Consumption of Leccinum mushrooms with elevated Hg contents in Yunnan at rates of up to 300 g fresh product per week during the foraging season would not result in Hg intake that exceeds the provisional weekly tolerance limit of 0.004 mg kg(-1) body mass, assuming no Hg ingestion from other foods.

Evaluation of Mercury Contamination in Fungi Boletus Species from Latosols, Lateritic Red Earths, and Red and Yellow Earths in the Circum-Pacific Mercuriferous Belt of Southwestern China.

For the first time, highly elevated levels of mercury (Hg) have been documented for several species of the edible Fungi genus Boletus growing in latosols, lateritic red earths, and red and yellow earths from the Yunnan province of China. Analysis of Hg concentrations in the genus suggests that geogenic Hg is the dominant source of Hg in the fungi, whereas anthropogenic sources accumulate largely in the organic layer of the forest soil horizon. Among the 21 species studied from 32 locations across Yunnan and 2 places in Sichuan Province, the Hg was found at elevated level in all samples from Yunnan but not in the samples from Sichuan, which is located outside the mercuriferous belt. Particularly abundant in Hg were the caps of fruiting bodies of Boletus aereus (up to 13 mg kg-1 dry matter), Boletus bicolor (up to 5.5 mg kg-1 dry matter), Boletus edulis (up to 22 mg kg-1 dry matter), Boletus luridus (up to 11 mg kg-1 dry matter), Boletus magnificus (up to 13 mg kg-1 dry matter), Boletus obscureumbrinus (up to 9.4 mg kg-1 dry matter), Boletus purpureus (up to 16 mg kg-1 dry matter), Boletus sinicus (up to 6.8 mg kg-1 dry matter), Boletus speciosus (up to 4.9mg kg-1 dry matter), Boletus tomentipes (up to 13 mg kg-1 dry matter), and Boletus umbriniporus (up to 4.9 mg kg-1 dry matter). Soil samples of the 0–10 cm topsoil layer from the widely distributed locations had mercury levels ranging between 0.034 to 3.4 mg kg-1 dry matter. In Yunnan, both the soil parent rock and fruiting bodies of Boletus spp. were enriched in Hg, whereas the same species from Sichuan, located outside the mercuriferous belt, had low Hg concentrations, suggesting that the Hg in the Yunnan samples is mainly from geogenic sources rather than anthropogenic sources. However, the contribution of anthropogenically-derived Hg sequestered within soils of Yunnan has not been quantified, so more future research is required. Our results suggest that high rates of consumption of Boletus spp. from Yunnan can deliver relatively high doses of Hg to consumers, but that rates can differ widely because of large variability in mercury concentrations between species and locations.

Discrimination of wild Paris based on near infrared spectroscopy and high performance liquid chromatography combined with multivariate analysis.

Different geographical origins and species of Paris obtained from southwestern China were discriminated by near infrared (NIR) spectroscopy and high performance liquid chromatography (HPLC) combined with multivariate analysis. The NIR parameter settings were scanning (64 times), resolution (4 cm−1), scanning range (10000 cm−1∼4000 cm−1) and parallel collection (3 times). NIR spectrum was optimized by TQ 8.6 software, and the ranges 7455∼6852 cm−1 and 5973∼4007 cm−1 were selected according to the spectrum standard deviation. The contents of polyphyllin I, polyphyllin II, polyphyllin VI, and polyphyllin VII and total steroid saponins were detected by HPLC. The contents of chemical components data matrix and spectrum data matrix were integrated and analyzed by partial least squares discriminant analysis (PLS-DA). From the PLS-DA model of NIR spectrum, Paris samples were separated into three groups according to the different geographical origins. The R2X and Q2Y described accumulative contribution rates were 99.50% and 94.03% of the total variance, respectively. The PLS-DA model according to 12 species of Paris described 99.62% of the variation in X and predicted 95.23% in Y. The results of the contents of chemical components described differences among collections quantitatively. A multivariate statistical model of PLS-DA showed geographical origins of Paris had a much greater influence on Paris compared with species. NIR and HPLC combined with multivariate analysis could discriminate different geographical origins and different species. The quality of Paris showed regional dependence.

Mineral Element Levels in Wild Edible Mushrooms from Yunnan, China

Ten species of wild edible mushrooms (Boletus griseus, Boletus speciosus, Lactarius hygrophoroides, Leucopaxillus giganteus, Macrocybe gigantea, Melanoleuca arcuata, Morchella deliciosa, Mycena haematopus, Pulveroboletus ravenelii, and Tricholoma matsutake) collected from Yunnan province of China, were analyzed for ten mineral elements (calcium, chromium, cobalt, copper, iron, magnesium, manganese, potassium, sodium, and zinc) contents using ICP-AES. The minimum and maximum element contents of mushrooms were determined as milligrams per kilograms dry weight for Ca (38–470), Cr (0.45–6.3), Co (0.29–2.3), Cu (13–58), Fe (22–510), Mg (84–550), Mn (1.4–70), K (1,300–4,600), Na (190–670), and Zn (16–160). The mushrooms species with the highest levels of mineral elements were B. griseus for K and Na, P. ravenelii for Cu, M. deliciosa for Mn, L. giganteus for Cr and Fe, M. gigantea for Ca, Mg and Zn, T. matsutake for Co. These results demonstrate that the mineral element contents in mushrooms are considerably species dependent and affected by environmental factors.

Mercury contamination of fungi genus Xerocomus in the Yunnan province in China and the region of Europe

This article presents the results of the study on accumulation, distribution, contamination and probable dietary intake of total mercury (THg) in fruiting bodies of several species of Fungi genus Xerocomus, which emerged in the circum-Pacific mercuriferous belt region in southwestern China in Yunnan and beyond of the mercuriferous belts in the region of Europe. The mushrooms X. puniceus (Boletus amygdalinus), X. spadiceus (Boletus ferrugineus) and X. versicolor (X. rubellus) were from the Yunnan land, and X. badius (Boletus badius) was from the region of Europe in Belarus and X. badius, X. chrysenteron, X. ferrugineus, X. versicolor (X. rubellus) and X. subtomentosus from Poland. The THg in the fungal and soil materials was determined using validated method by cold-vapour atomic absorption spectroscopy. Estimated was also probable dietary intake and health risk from THg in Xerocomus spp. examined by consumers. The data showed that THg content of Xerocomus spp. emerged in the European localizations in Poland and Belarus is at an order of magnitude lower level than determined in samples from the Yunnan Province. A reason for an elevated content of THg in mushrooms from Yunnan can be related to abundance of Hg in the geochemical background of soils there. The assessed doses showed that a single meal composed of 300 g of fresh fruiting bodies of X. spadiceus from the Wuding localization in Yunnan in China if consumed once a week will provide THg at dose close to the provisional tolerable weekly intake (PTWI) value set for THg, while doses will be lower for all other localizations in Yunnan and Europe. In the Wuding localization in Yunnan a frequent consumption of X. spadiceus in volume exceeding 300 g of fresh fruiting bodies per week will provide THg at a dose exceeding the value of PTWI.

Phytochemicals and bioactivities of Paris species

The plants of genus Paris, as important Chinese traditional herbs, have been studied from phytochemicals and pharmacological viewpoints for decades, which resulted in the discovery of scores of secondary metabolites with various kinds of bioactivities. This article summarizes the research progress of the genus Paris in the phytochemical and pharmacological respects.

90)Sr in King Bolete Boletus edulis and certain other mushrooms consumed in Europe and China.

The (90)Sr activity concentrations released from a radioactive fallout have been determined in a range of samples of mushrooms collected in Poland, Belarus, China, and Sweden in 1996-2013. Measurement of (90)Sr in pooled samples of mushrooms was carried out with radiochemical procedure aimed to pre-isolate the analyte from the fungal materials before it was determined using the Low-Level Beta Counter. Interestingly, the Purple Bolete Imperator rhodopurpureus collected from Yunnan in south-western China in 2012 showed (90)Sr activity concentration at around 10 Bq kg(-1) dry biomass, which was greater when compared to other mushrooms in this study. The King Bolete Boletus edulis from China showed the (90)Sr activity in caps at around 1.5 Bq kg(-1) dry biomass (whole fruiting bodies) in 2012 and for specimens from Poland activity was well lower than 1.0 Bq kg(-1) dry biomass in 1998-2010. A sample of Sarcodonimbricatus collected in 1998 from the north-eastern region of Poland impacted by Chernobyl fallout showed (90)Sr in caps at around 5 Bq kg(-1) dry biomass. Concentration of (90)Sr in Bay Bolete Royoporus (Xerocomus or Boletus) badius from affected region of Gomel in Belarus was in 2010 at 2.1 Bq kg(-1) dry biomass. In several other species from Poland (90)Sr was at <0.5 to around 1.0 Bq kg(-1) dry biomass. Activity concentrations of (90)Sr in popular B. edulis and some other mushrooms collected from wild in Poland were very low (<1 Bq kg(-1) dry biomass), and values noted showed on persistence of this type of radioactivity in mushrooms over time passing from nuclear weapons tests and the Chernobyl nuclear power plant catastrophe.

Artificial 137Cs and 134Cs and natural 40K in sclerotia of Wolfiporia extensa fungus collected across of the Yunnan land in China

Dried sclerotia of Wolfiporia extensa has a long history of medicinal and grocery uses in Asia and elsewhere. This study aimed at providing and evaluating data on activity concentrations from artificial 137Cs and 134Cs radionuclides and natural 40K in sclerotia collected across of the Yunnan land in China, which is generally lacking information. Sclerotia of W. extensa showed a low contamination with 137Cs while 134Cs was below limit of quantification. Estimated, the nominal value of effective dose (μSv) received by adult eating annually 50 g of the ‘average’ Yunnans origin sclerotia contained in the ‘Fuling jiabing’ snack due to 137Cs could be between < 0.00091 and 0.0047 ± 0.0007 μSv per capita and at < 0.000015 to 0.000078 ± 0.000012 μSv per kg of body mass, which is a very low exposure. This study has revealed also that sclerotia of W. extensa are characterized by very low content of 40K (hence also of total K) when compared to fruiting bodies of many saprobic and mycorrhizal mushrooms.