ATTENUATED TOTAL REFLECTION FOURIER TRANSFORM INFRARED (ATR-FTIR): A METHOD FOR THE BIOCHEMICAL STUDY OF WALNUT LEAVES

Abstract

ATR-FTIR spectra appear to function as biochemical fingerprints unique to each species and is used in our study to characterize eight walnut cultivars with different geographic origins and different agro-biological characteristics. Leaves were collected from four Romanian cultivars (‘Verisval’, ‘Valrex’, ‘Germisara’, ‘Jupâneşti’), three American (‘Serr’, ‘Payne’ and ‘Vina’) and one French cultivar (‘Franquette’) and were analysed using ATR-FTIR Spectroscopy combined with multivariate data analysis (PCA). ‘Franquette’ variety separates from the rest of the cultivars (Romanian and American). Analysis of PCA loadings identifies the specific spectral regions: 3000-2800 cm-1, 1750-1600 cm-1 and 1250-1200 cm-1, which are responsible for these differences in walnut leaves. No further sample preparation is required for ATR-FTIR and the measurement time of less than 1 min per sample will come more frequently method for analysing the biochemical composition of biological material, as well as a further tool for discrimination of walnut cultivars.

Keywords

• atr-ftir
• biochemical constituents
• walnut leaves