A comparison of toxic and essential elements in edible wild and cultivated mushroom species

GIS-based Visualization of Elemental Distribution in Neoboletus Luridiformis Fruiting Body

The fruiting body of Neoboletus luridiformis (Scarletina bolete) mushroom was used to determine the level of bioconcentration and subsequent distribution of seventeen elements (Ag, Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Sr, and Zn). A two-centimeter-thick vertical section of the entire fruit body was divided into 101 partial sub-samples where the contents of the studied elements were determined using ICP OES. The actual distribution of the elements in the fruiting body profile was visualized using a GIS interpolation method resulting in distribution maps. The study provides valuable insights into the distribution patterns of 17 elements within the fruiting body of N. luridiformis. Based on the visualization of the elemental content, the determined elements can be divided into three categories. Elements accumulated primarily (i) in the cap (Al, Ag, Ca, Cd, Cu, Fe, K, Mg, Ni, and Zn), (ii) in the stipe (Ba, Mn, Na, Pb, and Se), and (iii) elements with non-specific distribution (Cr and Sr). Since such detailed information supported by graphical visualization has not been published to date, the information in this study will help to better understand the accumulation and distribution of elements within the fruiting bodies of wild as well as cultivated mushroom species.

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.

Edible Mushrooms for Sustainable and Healthy Human Food: Nutritional and Medicinal Attributes

Global food production faces many challenges, including climate change, a water crisis, land degradation, and desertification. These challenges require research into non-traditional sources of human foods. Edible mushrooms are considered an important next-generation healthy food source. Edible mushrooms are rich in proteins, dietary fiber, vitamins, minerals, and other bioactive components (alkaloids, lactones, polysaccharides, polyphenolic compounds, sesquiterpenes, sterols, and terpenoids). Several bioactive ingredients can be extracted from edible mushrooms and incorporated into health-promoting supplements. It has been suggested that several human diseases can be treated with extracts from edible mushrooms, as these extracts have biological effects including anticancer, antidiabetic, antiviral, antioxidant, hepatoprotective, immune-potentiating, and hypo-cholesterolemic influences. The current study focuses on sustainable approaches for handling edible mushrooms and their secondary metabolites, including biofortification. Comparisons between edible and poisonous mushrooms, as well as the common species of edible mushrooms and their different bioactive ingredients, are crucial. Nutritional values and the health benefits of edible mushrooms, as well as different biomedical applications, have been also emphasized. Further research is needed to explore the economic sustainability of different medicinal mushroom bioactive compound extracts and their potential applications against emerging diseases such as COVID-19. New approaches such as nano-biofortification are also needed to supply edible mushrooms with essential nutrients and/or to increase their bioactive ingredients.

Green Biotechnology of Oyster Mushroom (Pleurotus ostreatus L.): A Sustainable Strategy for Myco-Remediation and Bio-Fermentation

The field of biotechnology presents us with a great chance to use many organisms, such as mushrooms, to find suitable solutions for issues that include the accumulation of agro-wastes in the environment. The green biotechnology of mushrooms (Pleurotus ostreatus L.) includes the myco-remediation of polluted soil and water as well as bio-fermentation. The circular economy approach could be effectively achieved by using oyster mushrooms (Pleurotus ostreatus L.), of which the substrate of their cultivation is considered as a vital source for producing biofertilizers, animal feeds, bioenergy, and bio-remediators. Spent mushroom substrate is also considered a crucial source for many applications, including the production of enzymes (e.g., manganese peroxidase, laccase, and lignin peroxidase) and bioethanol. The sustainable management of agro-industrial wastes (e.g., plant-based foods, animal-based foods, and non-food industries) could reduce, reuse and recycle using oyster mushrooms. This review aims to focus on the biotechnological applications of the oyster mushroom (P. ostreatus L.) concerning the field of the myco-remediation of pollutants and the bio-fermentation of agro-industrial wastes as a sustainable approach to environmental protection. This study can open new windows onto the green synthesis of metal-nanoparticles, such as nano-silver, nano-TiO2 and nano-ZnO. More investigations are needed concerning the new biotechnological approaches.

Radiocesium in Shiitake mushroom: Accumulation in living fruit bodies and leaching from dead fruit bodies

In this paper, cesium (Cs) accumulation by the saprophytic fungus Lentinula edodes (Shiitake) was investigated to contribute to the elucidation of radiocesium-cycling mechanisms in forest environments. Although the ¹³⁷Cs in the mushroom bed before culture was bioavailable, the transfer factor (TF) of Cs (¹³³Cs and ¹³⁷Cs) from the mushroom bed to fruit bodies was low (approximately 1) and the TFs of K (5) and Na (1.5) were higher. Cs and K concentrations in fruit bodies at different maturity stages were almost constant. The concentration ratio of Cs/K is constant in the pileus regardless of the pileus tissues. These results demonstrate that Shiitake non-specifically accumulates Cs while accumulating the essential element K and provide evidence that no selective Cs accumulation (or binding) sites exist within the Shiitake fruit body. Furthermore, the present results show that most accumulated Cs quickly leaches out from the dead fruit body with exposure to water. The leached Cs was largely adsorbable on clay minerals, suggesting that the Shiitake fruit body likely contains Cs in the cation form.