Enhancing the lithium content of white button mushrooms Agaricus bisporus using LiNO3 fortified compost: effects on the uptake of Li and other trace elements

Comment on "Worldwide basket survey of multielemental composition of white button mushroom Agaricus bisporus": The credibility of the concentration data reported for REE are questioned - are they reliable enough to be included in the database on nutrients in mushrooms?

The focus of this comment is on the Lanthanides (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) which, together with Sc and Y are also called the rare earth elements (REE). Individual REE have similar chemical properties and can be treated as a group. They behave similarly in the environment and in food webs. However, the determination of REE in foods, including edible mushrooms is analytically very challenging. In study by Siwulski et al. (2020) concentrations were reported for Ce, Nd, Sm, La, Sm and Tm, but the others were not detected above the method quantification limit. The sum of Ce (340-2730 μg kg^-1 dw), Nd (10-1220 μg kg^-1 dw), Sm (10-420 μg kg^-1 dw), La (10-130 μg kg^-1 dw), Sm (10-420 μg kg^-1 dw), Tm (10-170 μg kg^-1 dw) in 32 samples of A. bisporus was in the range of 430-3510 μg kg^-1 dry weight. The first visible characteristic is a large difference in the concentrations of Ce, Nd, Sm, La and Tm between the A. bisporus samples and various wild species and cultivated Cyclocybe cylindracea and Pleurotus ostreatus. Secondly, there is no correspondence with the Oddo-Harkins order and the concentrations pattern of Ce, Nd, Sm, La and Tm reported for the A. bisporus samples. The pattern is clearly different from that observed in the wild mushrooms and the two cultivated species reported by other studies. The ICP-OES and also the low resolution ICP-MS determination of REE directly from a fungal digest can suffer from spectral interferences of different types including an effect of the matrix which have to be overcome in the course of reliable and controlled analysis of REE.

Assessment of nutrient contents and bio-functional activities of edible fungus bio-fortified with copper, lithium and zinc

Bio-enrichment of edible mushrooms is an outstanding strategy to deliver essential nutrients to human. In this study, an edible fungus; Pleurotus pulmonarius was cultivated on spent mushroom substrate (SMS) supplemented with copper, lithium, and zinc. Proximate and mineral analysis of cultivated mushroom was determined using methods of AOAC. Antimicrobial activity of cultivated mushroom was assessed against microorganisms using agar well diffusion. Antioxidant property of mushroom was assessed against free radicals. Similar (p ≤ 0.05) protein contents of 18.93%, 18.80% and 17.90% were respectively obtained in P. pulmonarius biofortified with Cu + Li + Zn, Cu + Zn and Zn. Crude fibre in element fortified-mushroom ranged from 9.02 to 10.11%, while non-fortified mushroom was 8.66%. Copper content of P. pulmonarius fortified with Cu alone and Cu + Zn were 96.12 mg/100 g and 98.09 mg/100 g, respectively. Mushroom fortified with Zn has the highest zinc content of 520.15 mg/100 g. Mushroom fortified with Li and Li + Zn have a similar (p ≤ 0.05) Li content of 106.02 mg/100 g and 104.30 mg/100 g, respectively. Extract from mushroom-fortified with copper has the highest zone of inhibition (15.1 mm) against Klebsiella pneumoniae at 1.0 mg/ml. Mushroom fortified with Cu + Li + Zn and Li + Zn, respectively have similar (p ≤ 0.05) scavenging activities of 79.10 and 81.0% against DPPH. Mushroom fortified with Zn or Zn + Cu enhanced the growth of Lactobacillus acidophilus and Lactobacillus plantarum. Antimicrobial, antioxidant and prebiotic activities of fortified-mushroom could be attributed to arrays of phytochemicals and bio-accumulated elements. Hence, bio-fortified mushrooms can be used as functional foods and as biopharmaceuticals to treat ailments associated with nutrient deficient.

Nutritional and Other Trace Elements and Their Associations in Raw King Bolete Mushrooms, Boletus edulis

The occurrence and associations of Ag, As, Ba, Bi, Cd, Co, Cu, Cs, Hg, Ni, Pb, Rb, Sb, Sr, Tl, U, V, W, and Zn, including data that have not been previously reported on Be, Hf, In, Li, Mo, Nb, Sn, Ta, Th, Ti and Zr, and the sum of (14) rare earth elements (ƩREE), were studied in a spatially diverse collection of the B. edulis caps, stipes, and whole fruiting bodies using a validated procedure with measurement by quadrupole ICP-MS. Toxic Cd and Pb were in B. edulis at concentrations below limits set by the European Union in regulations for raw cultivated mushrooms, while Ag, As, Hg, Sb, Tl, and U, which are not regulated, were at relatively low or typical levels as is usually found in mushrooms from an unpolluted area. The elements Be, Bi, Ga, Ge, Hf, In, Nb, Ta, Th, and W, and also ƩREEs, were found at relatively low concentrations in B. edulis, i.e., with levels from below 0.1 to below 0.01 mg kg-1 dw, and for Ʃ14 REEs, the median was 0.31 mg kg-1 dw. The composite samples of caps showed Ag, Cd, Cu, Cs, Ga, Ge, Hg, Mo, Ni, Rb, Sb, Ti, and Zn at higher concentrations than stipes, while Ba, Co, Hf, Sr, Tl, and Zr were found at higher concentrations in stipes than caps (p < 0.05). Mushrooms were characterized by a low coefficient of variation (CV) of below 20%, between sites for concentrations of As, Cu, Ge, Hg, Ni, V, and Zn, while substantial differences (CV > 100%) were found for Ba, Bi, Co, Hf, Zr, and ƩREEs, and an intermediate variation was found for Sr, W, and U. Principal component analysis performed on mushrooms allowed differentiation with respect to 13 collection sites and separation of a consignment that was specifically contaminated, possibly due to a legacy pollution, with significantly higher levels of Ba, Co, Ga, Li, Nb, Ni, Sr, Th, Ti, Y, Zr, and ƩREEs, and another due to possible recent pollution (Pb-gasoline and also Ni); two due to geological contamination because of the Bi, In, Sc, Sb, Sn, Ta, V and W; and one more, the Sudety Mts. site, which was considered as "geogenic/anthropogenic" due to Ag, As, Be, Cd, Cs, Ni, Pb, Rb, Tl, and U.

Lithiation of white button mushrooms (Agaricus bisporus) using lithium-fortified substrate: effect of fortification levels on Li uptake and on other trace elements

High doses of lithium salts are used for the treatment or prevention of episodes of mania in bipolar disorder, but the medication is rapidly excreted and also shows side effects. Li may also be beneficial in people with mood disorders. Nutritionally, popular foods such as wild and cultivated mushrooms have low Li contents. This study evaluated the Li enrichment of white Agaricus bisporus mushrooms using Li₂CO₃ solutions to fortify the commercial growing substrate at various concentrations from 1.0 to 500 mg kg^-1 dry weight (dw). Fortification of up to 100 mg kg^-1 dw resulted in a significant (p < 0.01) dose-dependent increase in the accumulation of Li in mushroom, but the highest fortification level was found to be detrimental to fruitification. The median values of Li in fortified mushrooms corresponded to the fortification levels, increasing from 0.49 to 17 mg kg^-1 dw relative to the background concentration of 0.056 mg kg^-1 dw (control substrate contained 0.10 mg kg^-1 dw). The potential for Li uptake in fruiting bodies was found to decrease at higher levels of fortification, with saturation occurring at 100 mg kg^-1. Resulting lithiated mushrooms were up to 300-fold richer in Li content than specimens grown on control substrate. The fortification showed some effects on the uptake of other trace minerals, but concentrations of co-accumulated Ag, Al, As, Ba, Cd, Co, Cr, Cs, Cu, Hg, Mn, Ni, Pb, Rb, Sr, Tl, U, V and Zn were similar or lower than values reported in the literature for commercial A. bisporus. These lithiated mushrooms could be considered as a pro-medicinal alternative to treatments that use Li salts.

Lithiation of Agaricus bisporus mushrooms using compost fortified with LiOH: Effect of fortification levels on Li uptake and co-accumulation of other trace elements

This study investigated the lithiation of white Agaricus bisporus (common button) mushrooms using compost fortified with LiOH solutions at concentrations from 1 to 500 mg kg^-1 compost dw. Apart from the highest level of fortification, the median Li concentrations in the cultivated mushrooms were elevated from 0.74 to 21 mg kg^-1 dw (corresponding to compost fortification from 1.0 to 100 mg LiOH, kg^-1 dw), relative to control mushrooms at 0.031 mg kg^-1 dw. The bio-concentration potential for Li uptake in fruiting bodies was found to decrease at higher levels of fortification e.g. 50 - 100 mg kg^-1 dw, and at the highest level - 500 mg kg^-1, the mycelium failed to produce mushrooms. The fortification of the compost with LiOH appears to have had little, if any, effect on the co-accumulation of other elements such as Ag, Al, As, Ba, Cd, Co, Cr, Cs, Cu, Hg, Mn, Ni, Pb, Rb, Sr, Tl, U, V and Zn in the fruiting bodies, which generally occurred at the lower range of the results reported in the literature for cultivated A. bisporus. Thus compost fortification with LiOH provides an effective means of lithiating A. bisporus for potential pro-therapeutic use.

The use of Li2O fortified growing compost to enhance lithiation in white Agaricus bisporus mushrooms: Li uptake and co-accumulation of other trace elements

In an attempt to enrich the fruiting bodies with Lithium (Li), this study cultivated mushrooms using growing sets that were fortified with Li2O at 1.0, 5.0, 10, 50, 100 and 500 mg·kg−1 dw. Compost fortification up to 100 mg·kg−1 dw induced a dose-dependent increase in Li accumulation with resulting median mushroom concentrations of 2.0, 8.6, 16, 29 and 38 mg·kg−1 dw, respectively, relative to the unfortified control at 0.087 mg·kg−1 dw. The dose dependency appears to level off as Li2O addition approaches 100 mg·kg−1, suggesting that there is a limit to the ability of the species to accumulate/tolerate Li. Mushrooms did not grow at the 500 mg·kg−1 dw fortification level. At the highest viable level of fortification (100 mg·kg−1 dw), the fruiting bodies were around 440-fold richer in Li content than the control mushrooms. Additionally, the fortification at all levels up to 100 mg·kg−1 dw showed very low, if any, effect on the co-accumulation of the other, studied trace mineral constituents, with concentrations occurring at the lower range of those reported for commercial A. bisporus mushrooms.