Use of ATR-FTIR Spectroscopy and Chemometrics for the Variation of Active Components in Different Harvesting Periods of Lonicera japonica

Abstract

Lonicera japonica Thunb is a commonly used Chinese herbal medicine, which belongs to the family Caprifoliaceae. The active components varied greatly during bud development. Research on the variation of the main active components is significant for the timely harvesting and quality control of Lonicera japonica. In this study, the attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) combined with the chemometric method was performed to investigate the variability of different harvesting periods of Lonicera japonica. The preliminary characterization from ATR-FTIR fingerprints showed various characteristic absorption peaks of the main active components from the different harvesting times, such as flavonoids, organic acids, iridoids, and volatile oils. Additionally, principal component analysis (PCA) scatter plots showed that there was a clear clustering trend in the samples of the same harvesting period, and the samples of the different harvesting periods could be well distinguished. Finally, further analysis by the orthogonal partial least-squares discriminant analysis (OPLS-DA) showed that there were regular changes in flavonoids, phenolic acids, iridoids, and volatile oils in different harvesting periods. Therefore, ATR-FTIR, as a novel and convenient analytical method, could be applied to evaluate the quality of Lonicera japonica.

Romanian Viscum album L.—Untargeted Low-Molecular Metabolomic Approach to Engineered Viscum–AuNPs Carrier Assembly

“…The spectra of nanoparticle carrier assembly ( Figure 3 a) show the characteristic absorption bands of the viscum sample as well as the AuNPs coated with a surfactant (trisodium citrate) ( Figure 3 a,b). In addition, the peaks at 1622, 1371, 1258, 1114, and 660 cm −1 were found in the synthesized AuNP solution ( Figure 3 a) and are shifted to higher wavenumbers (1641, 1382, 1267, 1153 and 671 cm −1 ), indicating binding of nanoparticles to the functional groups O–H, C=O, C–N, C–S, and C–O belonging to the various phytoconstituents ( Figure 3 a,b and Table 3 ) [ 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 ]. In particular, the hydroxyl group is considered to be involved in the binding of AuNPs [ 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 ].…”

“…In addition, the peaks at 1622, 1371, 1258, 1114, and 660 cm −1 were found in the synthesized AuNP solution (Figure 3a) and are shifted to higher wavenumbers (1641, 1382, 1267, 1153 and 671 cm −1 ), indicating binding of nanoparticles to the functional groups O-H, C=O, C-N, C-S, and C-O belonging to the various phytoconstituents (Figure 3a,b and Table 3) [79][80][81][82][83][84][85][86][87][88][89][90][91]. In particular, the hydroxyl group is considered to be involved in the binding of AuNPs [85][86][87][88][89][90][91][92][93][94][95][96][97][98]. 3) [79][80][81][82][83][84][85][86][87][88][89][90][91].…”

“…In particular, the hydroxyl group is considered to be involved in the binding of AuNPs [85][86][87][88][89][90][91][92][93][94][95][96][97][98]. 3) [79][80][81][82][83][84][85][86][87][88][89][90][91]. In particular, the hydroxyl group is considered to be involved in the binding of AuNPs [85][86][87][88][89][90][91][92][93][94][95][96][97][98].…”

“…3) [79][80][81][82][83][84][85][86][87][88][89][90][91]. In particular, the hydroxyl group is considered to be involved in the binding of AuNPs [85][86][87][88][89][90][91][92][93][94][95][96][97][98]. Figure 4a shows the specific XRD spectrum of AuNPs.…”

Discrimination and Prediction of Lonicerae japonicae Flos and Lonicerae Flos and Their Related Prescriptions by Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy Combined with Multivariate Statistical Analysis

“…ATR-FTIR technology has been developed based on FTIR technology, which can be equipped with ATR accessories for crystal materials [ 10 ], and is a fast, convenient, non-destructive, and high-throughput analytical tool that is widely used in the rapid identification and quality control of herbal medicines [ 11 ]. However, the obtained FT-IR spectra can be affected by the characteristics of samples in thickness and particle size [ 12 , 13 ], so the acquired raw data should be normalized.…”