Selenium uptake, toxicity and reduction in Flammulina velutipes supplied with selenite
- Published
- Accepted
- Subject Areas
- Agricultural Science, Biochemistry, Mycology
- Keywords
- cultivated mushrooms, selenite uptake, selenite toxicity, biological nanoparticle synthesis, Flammulina velutipes
- Copyright
- © 2016 Wang et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ PrePrints) and either DOI or URL of the article must be cited.
- Cite this article
- 2016. Selenium uptake, toxicity and reduction in Flammulina velutipes supplied with selenite. PeerJ PrePrints 4:e1660v1 https://doi.org/10.7287/peerj.preprints.1660v1
Abstract
Recently, selenium (Se) enriched mushrooms have been exploited as diary Se supplements, but our knowledge of the metabolism process during the Se enrichment process is far from complete. In this study, the uptake, toxicity and reduction of selenite in a widely cultivated mushroom, Flammulina velutipes, was investigated. The results showed that pH variation (from 5.5 to 7.5), metabolic inhibitor (0.1 mM 2,4-DNP) and P or S starvation led to 11%-26% decreases in the selenite uptake rate of F. velutipes. This indicates that a minor portion of the selenite uptake was metabolism dependent, whereas a carrier-facilitated passive transport may be crucial. Growth inhibition of F. velutipes initiated at 0.1 mM selenite (11% decrease in the growth rate) and complete growth inhibition occurred at 3 mM selenite. A selenite concentration of 0.03-0.1 mM was recommended to maintain the balance between mycelium production and Se enrichment. F. velutipes was capable of reducing selenite to Se(0) nanoparticles, possibly as a detoxification mechanism. This process depended on both selenite concentration and metabolism activity. Overall, the data obtained provided some basic information for the cultivation of the selenized F. velutipes, and highlighted the opportunity of using mushrooms for the production of Se(0) nanoparticles.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Raw data of the experiments
Raw data of the uptake and toxicity experiments.
The colony of F. velutipes in the selenite-free substrate (A) and the coral-like colony margin after 1 mM selenite treatment for 20 days (B)
The positions of the red coloration in the solid (a and b), static (c and d) and shaking (e and f) cultivations
The green arrows indicate the inocula.
The intensities of red coloration in 12 species of mushrooms
(A): solid cultivation supplied with 0.1 mM selenite; (B): shaking cultivation supplied with 0.3 mM selenite after the mycelial pellets had been cultivated in selenite-free media for 9-17 days. Intensities of the red color in the circles represent the red coloration of the colonies (only the most intense part were shown). The squares mean no clear reduction was observed because of the pigment interference. The numbers below the circles represent the time (day) when the colony started to turn red after selenite addition. The plus/minus signs on the top of circles or squares in (B) represent the intensities of garlic smell after selenite treatment for 3 days (−: none; +: low; ++: moderate; +++: high).