Honggao Liu

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.

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.

Geographical traceability of wild Boletus edulis based on data fusion of FT-MIR and ICP-AES coupled with data mining methods (SVM)

In this work, the data fusion strategy of Fourier transform mid infrared (FT-MIR) spectroscopy and inductively coupled plasma-atomic emission spectrometry (ICP-AES) was used in combination with Support Vector Machine (SVM) to determine the geographic origin of Boletus edulis collected from nine regions of Yunnan Province in China. Firstly, competitive adaptive reweighted sampling (CARS) was used for selecting an optimal combination of key wavenumbers of second derivative FT-MIR spectra, and thirteen elements were sorted with variable importance in projection (VIP) scores. Secondly, thirteen subsets of multi-elements with the best VIP score were generated and each subset was used to fuse with FT-MIR. Finally, the classification models were established by SVM, and the combination of parameter C and γ (gamma) of SVM models was calculated by the approaches of grid search (GS) and genetic algorithm (GA). The results showed that both GS-SVM and GA-SVM models achieved good performances based on the #9 subset and the prediction accuracy in calibration and validation sets of the two models were 81.40% and 90.91%, correspondingly. In conclusion, it indicated that the data fusion strategy of FT-MIR and ICP-AES coupled with the algorithm of SVM can be used as a reliable tool for accurate identification of B. edulis, and it can provide a useful way of thinking for the quality control of edible mushrooms.

Content and Bioaccumulation of Nine Mineral Elements in Ten Mushroom Species of the Genus Boletus

Concentrations and bioconcentration potential of nine elements (Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn) in ten species of wild edible Boletus and the corresponding underlying soils were analyzed. The analyses were performed using inductively coupled plasma atomic emission spectrophotometer. Boletus showed relative abundant contents of P, K, Fe, Mg, Ca, and Na and less of Zn, Cu, and Mn. Caps compared to stalks were enriched in P, K, Cu, Mg, and Zn, while stalks were enriched in Mn. The elements such as P and K were accumulated (BCF > 1), while Ca, Fe, Mg, Mn, and Na were excluded (BCF < 1) in the fruiting bodies. The correlation analysis indicated high correlations between Cu, Mn, Ca, and Fe in the mushrooms as compared to the corresponding soils. Significant correlations were also obtained between Cu-P (r = 0.775), Fe-P (r = 0.728), and Zn-P (r = 0.76) for caps and Cu-Mg (r = 0.721), Fe-Mg (r = 0.719), Zn-Mg (r = 0.824), and Zn-P (r = 0.818) for stalks. The results of this study imply that ability of fungi to accumulate elements from substrate could be influenced by mushroom species and underlying soil substrates.

Ultraviolet spectroscopy combined with ultra-fast liquid chromatography and multivariate statistical analysis for quality assessment of wild Wolfiporia extensa from different geographical origins

A quality assessment system comprised of a tandem technique of ultraviolet (UV) spectroscopy and ultra-fast liquid chromatography (UFLC) aided by multivariate analysis was presented for the determination of geographic origin of Wolfiporia extensa collected from five regions in Yunnan Province of China. Characteristic UV spectroscopic fingerprints of samples were determined based on its methanol extract. UFLC was applied for the determination of pachymic acid (a biomarker) presented in individual test samples. The spectrum data matrix and the content of pachymic acid were integrated and analyzed by partial least squares discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA). The results showed that chemical properties of samples were clearly dominated by the epidermis and inner part as well as geographical origins. The relationships among samples obtained from these five regions have been also presented. Moreover, an interesting finding implied that geographical origins had much greater influence on the chemical properties of epidermis compared with that of the inner part. This study demonstrated that a rapid tool for accurate discrimination of W. extensa by UV spectroscopy and UFLC could be available for quality control of complicated medicinal mushrooms.

A Comprehensive and Comparative Study of Wolfiporia extensa Cultivation Regions by Fourier Transform Infrared Spectroscopy and Ultra-Fast Liquid Chromatography

Nowadays, Wolfiporia extensa as a popular raw material in food and medicine industry has received increasing interests. Due to supply shortage, this species of edible and medicinal mushroom has been cultivated in some provinces of China. In the present study, cultivated W. extensa collected from six regions in Yunnan Province of China were analyzed by an integrated method based on Fourier transform infrared (FT-IR) spectroscopy and ultra-fast liquid chromatography (UFLC) coupled with multivariate analysis including partial least squares discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) in order to investigate the differences and similarities in different origins and parts. In the tested mushroom samples, characteristic FT-IR spectra were obtained for acquiring comprehensive fuzz chemical information and pachymic acid was determinated as a biomarker in the meantime. From the results, the comparison of samples was achieved successfully according to their geographical regions and different parts. All the samples displayed regional dependence and the inner parts showed better quality consistency. In addition, the chemical constituents of cultivated W. extensa could be also affected by the cultivation methods. Meanwhile, there was an interesting finding that the soil properties of cultivation regions may have a relationship with the chemical constituents of the epidermis of soil-cultured W. extensa, rather than the inner parts. Collectively, it demonstrated that the present study could provide comprehensive chemical evidence for the critical complement of quality evaluation on the cultivated W. extensa. Moreover, it may be available for the further researches of complicated mushrooms in practice.

Variations in Element Levels Accumulated in Different Parts of Boletus edulis Collected from Central Yunnan Province, China

ICP-AES and microwave assisted digestion were applied to determine P, Mg, Ca, Zn, Na, Cu, Ba, Ni, V, Cd, Sr, Co, and Li in the caps and stipes of Boletus edulis collected from six spatially distant sites in Yunnan province, China. Fruiting bodies of King Bolete are abundant in P, Mg, Ca, Zn, Cu, and Na, followed by Ba, Cd, Ni, V, Li, Sr, and Co. Contents of P, Mg, Zn, and Cu are more abundant in caps than in stipes of King Bolete. However, elements such as Na, Ba, Cd, Ni, V, Li, Sr, and Co prefer to accumulate in stipes of mushrooms from Yaoan, Chuxiong. The results of this study indicate that spatial variations of elements between caps and stipes are mainly related to different bedrock soil geochemistry and enrichment capability for various elements.

Feature Fusion of ICP-AES, UV-Vis and FT-MIR for Origin Traceability of Boletus edulis Mushrooms in Combination with Chemometrics

Origin traceability is an important step to control the nutritional and pharmacological quality of food products. Boletus edulis mushroom is a well-known food resource in the world. Its nutritional and medicinal properties are drastically varied depending on geographical origins. In this study, three sensor systems (inductively coupled plasma atomic emission spectrophotometer (ICP-AES), ultraviolet-visible (UV-Vis) and Fourier transform mid-infrared spectroscopy (FT-MIR)) were applied for the origin traceability of 184 mushroom samples (caps and stipes) in combination with chemometrics. The difference between cap and stipe was clearly illustrated based on a single sensor technique, respectively. Feature variables from three instruments were used for origin traceability. Two supervised classification methods, partial least square discriminant analysis (FLS-DA) and grid search support vector machine (GS-SVM), were applied to develop mathematical models. Two steps (internal cross-validation and external prediction for unknown samples) were used to evaluate the performance of a classification model. The result is satisfactory with high accuracies ranging from 90.625% to 100%. These models also have an excellent generalization ability with the optimal parameters. Based on the combination of three sensory systems, our study provides a multi-sensory and comprehensive origin traceability of B. edulis mushrooms.