Fipke Laboratory for Trace Element Research, University of British Columbia Okanagan, Kelowna, BC, V1V 1V7, Canada.
Environmental Sciences Group, Royal Military College of Canada, Kingston, ON, K7K 7B4, Canada.
Environ Geochem Health. 2020 Sep;42(9):2723-2732. doi: 10.1007/s10653-019-00506-0. Epub 2020 Jan 2.
Uptake, distribution and speciation of arsenic (As) were determined in the bracket fungus Fomitopsis betulina (previously Piptoporus betulinus), commonly known as the birch polypore, collected from a woodland adjacent to a highly contaminated former mine in the Southwest UK and at an uncontaminated site in Quebec, Canada, with no past or present mining activity. The fruiting body was divided into cap, centre and pores representing the top, middle and underside to identify trends in the distribution and transformation of As. Total As, determined by inductively coupled plasma-mass spectrometry (ICP-MS), was approximately tenfold higher in the mushroom from the contaminated compared to the uncontaminated site. Overall, accumulation of As was low relative to values reported for some soil-dwelling species, with maximum levels of 1.6 mg/kg at the contaminated site. Arsenic speciation was performed on aqueous extracts via both anion and cation high-performance liquid chromatography-ICP-MS (HPLC-ICP-MS) and on whole dried samples using X-ray absorption near edge structure (XANES) analysis. Seven As species were detected in F. betulina from the contaminated site by HPLC-ICP-MS: arsenite (As), arsenate (As), dimethylarsinate (DMA), methylarsonate (MA), trimethylarsine oxide (TMAO), tetramethylarsonium ion (Tetra) and trace levels of arsenobetaine (AB). The same As species were observed at the uncontaminated site with the exception of TMAO and Tetra. Arsenic species were localized throughout the fruiting body at the contaminated site, with the cap and pores containing a majority of As, only the cap containing TMAO, and the pores containing higher concentrations of DMA and MA as well as tetra and a trace of AB. XANES analysis demonstrated that the predominant form of As at the contaminated site was inorganic As coordinated with sulphur or oxygen and As coordinated with oxygen. This is the first account of arsenic speciation in F. betulina or any fungi of the family Fomitopsidaceae.
在英国西南部一个紧邻高度污染的前矿区和加拿大魁北克一个未受污染的地点采集的白环乳牛肝菌（先前称为桦剥管菌）中，测定了砷（As）的摄取、分布和形态。该子实体被分为帽、中体和菌孔，分别代表顶部、中部和底部，以确定 As 分布和转化的趋势。电感耦合等离子体质谱法（ICP-MS）测定的总 As 含量在污染点采集的蘑菇中比未污染点高约十倍。总体而言，与一些土壤居住物种的报道值相比，As 的积累量相对较低，在污染点的最高水平为 1.6mg/kg。采用阴离子和阳离子高效液相色谱-电感耦合等离子体质谱法（HPLC-ICP-MS）对水提物进行砷形态分析，并采用 X 射线吸收近边结构（XANES）分析对整个干燥样品进行砷形态分析。通过 HPLC-ICP-MS 在污染点的白环乳牛肝菌中检测到 7 种 As 形态：亚砷酸盐（As）、砷酸盐（As）、二甲基砷酸（DMA）、甲基砷酸（MA）、三甲砷氧化物（TMAO）、四甲基砷离子（Tetra）和痕量的砷甜菜碱（AB）。在未污染点观察到相同的 As 形态，除了 TMAO 和 Tetra。在污染点，As 形态遍布整个子实体，帽和菌孔中含有大部分的 As，只有帽含有 TMAO，而菌孔中含有较高浓度的 DMA 和 MA 以及 tetra 和痕量的 AB。XANES 分析表明，污染点的主要 As 形态是与硫或氧配位的无机 As 和与氧配位的 As。这是首次对白环乳牛肝菌或任何乳牛肝菌科真菌的砷形态进行的研究。
