[Identification of three-step IR spectra of radix Puerariae from different habitats]

The IR spectra method and 2D-IR correlation spectra method were used for the identification of radix puerariae from Baxian mountain in Tianjin, Huping mountain in Hunan and Jinfo mountain in Chongqing. The results show that the IR spectra (the first identification) and the second derivative spectra (the second identification) of kudzu roots from different habitats have some similarity. Compared with the spectra of amylum and puerarin, three samples are all rich in amylum, and have some puerarin. The primary difference is the 62 wave numbers between the strongest peak of Tianjin kudzu at 1 048 cm(-1) and amylum at 986 cm(-1), showing that the content of amylum is lower. Radix puerariae from Tianjin has characteristic peaks consistent with those of puerarin at 891, 835 and 797 cm(-1), which means that radix puerariae from Tianjin has more puerarin. In the 2D-IR correlation spectra (the third identification), the three kinds of radix puerariae have the difference in position and the intensity of the correlation peak cluster. Therefore, the three-step IR macro-fingerprint provides a rapid and effective method for the identification of radix puerariae from the different habitats.