Advances in Tools and Techniques to Quantify Melatonin in Plants and Foodstuff

As an ancient pleiotropic molecule, melatonin (N-acetyl-5-methoxytryptamine) regulates numerous cellular, physiological, biochemical, and molecular processes in plants. Although the existence of melatonin has been well documented over 27 years in photosynthetic organisms, research into the phytomelatonin is still limited due to lower endogenous concentrations in complex plant metrics and lack of rapid efficient quantification techniques. Therefore, scientists worldwide showed extensive efforts to develop sensitive detection tools and techniques for future innovative research and human well-being. Among the various analytical methods selective high performance liquid chromatography mass spectrophotometry (HPLC-MS) is largely used for high selectivity, accuracy, robustness, and low limit of detection. However, in recent years micro-fabrication and nanomaterial-mediated decoration of novel electrochemical and optical detection tools draw extra attention in addition to capillary electrophoresis, fluorimetry or immunological assay due to their wider biocompatibility, sensitivity, range limit, and precision detection. In this chapter, we summarize recent technological advances in melatonin quantification in plant samples and discuss the challenges of developed techniques in phytomelatonin research.