Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) Combined with Chemometrics Methods for the Classification of Lingzhi Species

Abstract

Due to the existence of Lingzhi adulteration, there is a growing demand for species classification of medicinal mushrooms by various techniques. The objective of this study was to explore a rapid and reliable way to distinguish between different Lingzhi species and compare the influence of data pretreatment methods on the recognition results. To this end, 120 fresh fruiting bodies of Lingzhi were collected, and all of them were analyzed by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). Random forest (RF), support vector machine (SVM) and partial least squares discriminant analysis (PLS-DA) classification models were established for raw and pretreated second derivative (SD) spectral matrices to authenticate different Lingzhi species. The results of multivariate statistical analysis indicated that the SD preprocessing method displayed a higher classification ability, which may be attributed to the analysis of powder samples that requires removal of overlapping peaks and baseline shifts. Compared with RF, the results of the SVM and PLS-DA methods were more satisfying, and their accuracies for the test set were both 100%. Among SVM and PLS-DA, the training set and test set accuracy of PLS-DA were both 100%. In conclusion, ATR-FTIR spectroscopy data pretreated by SD combined with PLS-DA is a simple, rapid, non-destructive and relatively inexpensive method to discriminate between mushroom species and provide a good reference to quality assessment.

Isaria tenuipes Peck, an entomopathogenic fungus from Darjeeling Himalaya: Evaluation of in-vitro antiproliferative and antioxidant potential of its mycelium extract

“…The present study preliminarily confirmed the presence of varied phytoconstituents with characteristic IR band in the mycelium extract. The chemical profile obtained in this study is comparable with data obtained by different workers from the different members of medicinal mushrooms [54,55].…”

“…The extract had characteristic IR bands that comprehensively indicate the presence of carbohydrates mainly polysaccharides, protein, and aromatic compounds. The peak recorded at 3292 cm −1 is the result of stretching vibrations of N-H and OH tentatively in the polysaccharides, triterpenes, and sterols [54]. The absorption around 2931 cm −1 (aliphatic C-H stretching, asymmetric) represent the hydrocarbon chain in the sample extract.…”

Pleurotus Mushrooms Content in Glucans and Ergosterol Assessed by ATR-FTIR Spectroscopy and Multivariate Analysis

“…In the mushroom industry, such a tool (i.e., predicting the content of mushrooms in selected constituents) could be of great interest both for the growers, as a way of promoting a product of high nutraceutical value, as well as for companies processing mushrooms to produce health promoting foods or drugs/cosmetics. To date, FTIR spectroscopy has been mainly applied to identify various filamentous fungi [27,28], to delimit taxa within the genera Pleurotus, Ganoderma and Boletus [29][30][31], to discriminate among mushroom samples of the same species on the basis of geographic origin [32] or to evaluate the post-harvest quality properties in Agaricus bisporus mushrooms [33]. To the best of the authors' knowledge, no PAT tool exists for the assessment of mushroom content in bioactive compounds.…”

Viscothermal Behavior and Structural Characterization of Temperate Highland Himalayan Rice Cultivars

“…The spectral region of 1216.9 cm −1 (Jhelum) to 1254.249 cm −1 (Koshikari) found in all the selected variety except that of Chenab can be assigned to amide‐III band, which are mostly due to absorption of proteins, [ 53 ] while absorption peak of 1190 cm −1 in case of Chenab can be assigned to absorption of starch. [ 54 ] The preliminary inference drawn from ATR‐FTIR results was that the spectra shapes were almost similar for all the selected highland Himalayan rice cultivars but there was some dissimilarity in their chemical profile.…”