Chemical Fingerprinting Profile and Targeted Quantitative Analysis of Phenolic Compounds from Rooibos Tea (Aspalathus linearis) and Dietary Supplements Using UHPLC-PDA-MS

Recent Advances in Analysis of Food and Beverages

In this section, we summarize the characteristics of the published papers according to different typologies [...]

On-Site Multisample Determination of Chlorogenic Acid in Green Coffee by Chemiluminiscent Imaging

The potential of antioxidants in preventing several diseases has attracted great attention in recent years. Indeed, these products are part of a multi-billion industry. However, there is a lack of scientific information about safety, quality, doses, and changes over time. In the present work, a simple multisample methodology based on chemiluminiscent imaging to determine chlorogenic acid (CHLA) in green coffee samples has been proposed. The multi-chemiluminiscent response was obtained after a luminol-persulfate reaction at pH 10.8 in a multiplate followed by image capture with a charge-coupled device (CCD) camera as a readout system. The chemiluminiscent image was used as an analytical response by measuring the luminescent intensity at 0 °C with the CCD camera. Under the optimal conditions, the detection limit was 20 µM and precision was also adequate with RSD < 12%. The accuracy of the proposed system was evaluated by studying the matrix effect, using a standard addition method. Recoveries of chlorogenic acid ranged from 93-94%. The use of the CCD camera demonstrated advantages such as analysis by image inspection, portability, and easy-handling which is of particular relevance in the application for quality control in industries. Furthermore, multisample analysis was allowed by one single image saving time, energy, and cost. The proposed methodology is a promising sustainable analytical tool for quality control to ensure green coffee safety through dosage control and proper labelling preventing potential frauds.

Quality Evaluation of Crude and Salt-Processed Cuscutae Semen through Qualitative and Quantitative Analysis of Multiple Components Using HPLC Combined with Chemometrics

Cuscutae Semen (CS; Chinese common name “Tusizi”) is one of the most common traditional herbal medicines used to treat liver and kidney diseases in China. Although it is most commonly used as a processed product, little progress has been made on the quality control of CS and salt-processed Cuscutae Semen (PCS). The purpose of this study was to establish a comprehensive strategy integrating chromatographic analysis and chemometric methods for quality evaluation and discrimination of CS and PCS. An accurate and reliable HPLC method was established for the simultaneous quantification of 12 analyte compounds in CS and PCS. The results showed that this method exhibited desirable sensitivity, precision, stability, and repeatability. Multivariate chemometric methods were applied to analyze the obtained HPLC fingerprints, including hierarchical cluster analysis (HCA), principle component analysis (PCA), and partial least squares discriminant analysis (PLS-DA). The results indicated that CS and PCS samples showed a clear classification of the two groups, and three chemical markers with great contributions to the differentiation were screened out. Collectively, the chemometrics combined with the quantitative analysis based on HPLC fingerprint results indicated that salt processing may change the contents and types of components in Cuscutae Semen.