Advanced sample preparation and chromatographic techniques for analyzing plant-based bioactive chemicals in nutraceuticals

Since ancient times, humanity has used plants to cure diseases or maintain health. Nowadays, obtaining the bioactive components of plants and researching their effects continues at great speed. Plant-derived chemicals are studied with great interest in the food, pharmaceutical and cosmetic industries. The complexity of city life limits access to plants in their natural habitat. Nutraceuticals are indispensable products of our age to protect health. Many methods have been developed and successfully applied for extracting crude plant extracts and pure active substances included in nutraceuticals from plant tissues and their quantitative analysis. This study compiled the methods for obtaining plant extracts and active ingredients and the techniques developed for analyzing bioactive compounds. The extraction methods of plant-based bioactive chemicals (maceration, Soxhlet extraction, decoction, infusion, hydro distillation, ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE)) were explained in detail, and some important plant-based bioactive chemicals and source plants were summarized in table form. Additionally, the studies using different analytical techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), thin layer chromatography (TLC), mass spectrometry (MS), and ultra-performance liquid chromatography (UPLC) were discussed. Finally, evaluating its effectiveness in the extraction of different bioactive compounds and the prospects for more environmentally friendly methods alternative to traditional solvents were emphasized. This review covers the latest practices and new trends in analyzing plant-based bioactive chemicals in nutraceuticals over the last three years.