Verification of Ganoderma (lingzhi) commercial products by Fourier Transform infrared spectroscopy and two-dimensional IR correlation spectroscopy

•The content of Ganoderma commercial products can be detected using FTIR and 2DIR.•NL is a product from Sabah and 87% of its contents correlated with raw Ganoderma fruiting body cultivated in Semenyih.•The ingredients of Ganoderma from Tanjung Sepat were similar to YKG product.•The analysis proved that LC product contained starch as an excipient.•This study demonstrated the possibility of developing a verification tool to validate the purity of commercial products.