Forensic differentiation of amanita mushrooms using atr-ftir spectroscopy coupled with chemometrics

In mushroom poisoning cases, genus Amanita is responsible for majority of fatalities. Most of such cases are due to the accidental consumption of inedible mushrooms, but there is a high probability of their use forhomicidal purposes. Mushroom species can be identified based on the morphological features, however, in the field of forensic science,available exhibits are recovered in trace amounts, which pose a serious challenge before the forensic experts to analyse the samples in a non-destructive manner. In current work, ATR FT-IR spectroscopy has been used for the non-destructive identification and differentiation of six species of genus Amanita. To distinguish the selected mushroom species, chemometric tools like PCA and PLS-DA were applied. All samples were not successfully classified using the PCA model, therefore the PLS-DA model was applied to enhance the classification rate. PLS-DA model yielded a significant classification rate for the differentiation among the samples of different wild mushroom species. Furthermore, blind validation test was conducted and all unknown samples were classified accurately to their respective class. The obtained R-square value for PLS-DA model was 0.99 which is highly significant for the prediction accuracy.

Keeping in view the forensic casework conditions, another part of the study included discrimination of mushroom samples which were given various heat treatments like frying, boiling, grilling and baking. This study establishes a non-destructive approach which could discriminate wild mushroom samples in the dried and cooked form that can be encountered as evidence.

Differentiation of six species of genus Amanita using ATR-FTIR

Objective interpretation of results utilizing chemometric methods

100% accuracy was achieved for blind validation test

Heat treated samples were also analyzed

Current methodology is non-destructive, rapid, reliable and cost-efficient