1H-NMR Metabolic Profiling and Antioxidant Activity of Saffron (Crocus sativus) Cultivated in Lebanon

An overview of analytical methods employed for quality assessment of Crocus sativus (saffron)

This paper reviews qualitative and quantitative analytical methodologies used for the appraisal of saffron quality, as the most expensive spice. Due to the chemical diversity of biologically active compounds of the Crocus genus, analytical methods with different features are required for their complete analysis. However, screening of the main components, such as carotenoids and flavonoids, appears to be sufficient for quality control, a more precise examination needs evaluation of minor compounds, including anthocyanins and fatty acids. High-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), ultraviolet-visible spectroscopy (UV), nuclear magnetic resonance spectroscopy (NMR), and thin-layer chromatography (TLC), are elementary and applicable methods in quality control analysis, whereas HPLC provides metabolite fingerprint and monitoring multi-compound instances at preparative and analytical levels. Combination approaches like metabolomics using different methods could classify saffron types, identify its adulterations, contaminants and provide a comprehensive metabolite map for quality control of selected compounds.

Saffron Extract Attenuates Anxiogenic Effect and Improves Cognitive Behavior in an Adult Zebrafish Model of Traumatic Brain Injury

Traumatic brain injury (TBI) has the highest mortality rates worldwide, yet effective treatment remains unavailable. TBI causes inflammatory responses, endoplasmic reticulum stress, disruption of the blood-brain barrier and neurodegeneration that lead to loss of cognition, memory and motor skills. Saffron (Crocus sativus L.) is known for its anti-inflammatory and neuroprotective effects, which makes it a potential candidate for TBI treatment. Zebrafish (Danio rerio) shares a high degree of genetic homology and cell signaling pathways with mammals. Its active neuro-regenerative function makes it an excellent model organism for TBI therapeutic drug identification. The objective of this study was to assess the effect of saffron administration to a TBI zebrafish model by investigating behavioral outcomes such as anxiety, fear and memory skills using a series of behavioral tests. Saffron exhibited anxiolytic effect on anxiety-like behaviors, and showed prevention of fear inhibition observed after TBI. It improved learning and enhanced memory performance. These results suggest that saffron could be a novel therapeutic enhancer for neural repair and regeneration of networks post-TBI.

Changes of Crocin and Other Crocetin Glycosides in Saffron Through Cooking Models, and Discovery of Rare Crocetin Glycosides in the Yellow Flowers of Freesia Hybrida

Crocetin glycosides such as crocin are noted as functional food materials since the preventive effects of crocin have been reported against chronic disease and cancer. However, it is unclear how these apocarotenoids are structurally changed through cooking for our intake. We examined such changes in crocetin glycosides (crocin, tricrocin, and crocin-3) contained in saffron (stigmas of Crocus sativus) through cooking models. These glycosides were almost kept stable in boiling for 20 min (a boiled cooking model), while hydrolysis of the ester linkage between glucose and the crocetin aglycone occurred in a grilled cooking model (180°C, 5 min), along with a 13-cis isomerization reaction in a part of crocetin subsequently generated. We further here revealed that the yellow petals of freesia (Freesia x hybrida) with yellow flowers accumulate two unique crocetin glycosides, which were identified to be crocetin (mono)neapolitanosyl ester and crocetin dineapolitanosyl ester. A similar result as above was obtained on their changes through the cooking models. Utility applications of the freesia flowers as edible flowers are also suggested in this study. Additionally, we evaluated singlet oxygen (¹O₂)-quenching activities of the crocetin glycosides contained in saffron and freesia, and crocetin and 13-cis crocetin contained in the grilled saffron, indicating that they possessed moderate ¹O₂-quenching activities (IC₅₀ 24–64 μM).