Statistical analysis-based green planar chromatographic methodology for the quality assessment of food supplements: a case study on Origanum vulgare L. commercial products

Quality assessment is the most important step in the production of effective and safe food supplements. The aim of this study is to develop a green, simple, and high-throughput procedure for the quality assessment of Origanum vulgare L. commercial products using high-performance thin-layer chromatography (HPTLC)/bioautography with a multicriteria decision method, sum of ranking differences (SRD). Direct bioautography assays were developed for the identification of constituents with antibacterial activity tested against Gram-positive (Bacillus subtilis, Micrococcus lysodeikticus) and Gram-negative (Escherichia coli) strains, antioxidative (DPPH) activity, and enzyme (α-amylase) activity. Combination of the leave-one-out cross-validation methodology of SRD values and significant differences by post hoc Wilcoxon matched pairs test were used to evaluate commercial varieties. It was proved that suggested bioautography/chemometric screening methodology could be used as guidelines for the selection of any theoretical ideal product. Analysts may have benefits from this time-saving and streamlined quality profiling.