Comprehensive metabolite profiling in distinct chemotypes of Commiphora wightii

Phytochemical Characterization of Olea europaea L. Cultivars of Cilento National Park (South Italy) through NMR-Based Metabolomics

Olea europaea germplasm is constituted by a huge number of cultivars, each one characterized by specific features. In this context, endemic cultivars evolved for a very long period in a precise local area, developing very specific traits. These characteristics include the production and accumulation of phytochemicals, many of which are also responsible for the nutraceutical value of the drupes and of the oils therefrom. With the aim of obtaining information on the phytochemical profile of drupes of autochthonous cultivars of Cilento, Vallo di Diano and Alburni National Park, a metabolomics-based study was carried out on 19 selected cultivars. Multivariate data analysis of ¹H-NMR data and 2D NMR analyses allowed the rapid identification of metabolites that were qualitatively and/or quantitatively varying among the cultivars. This study allowed to identify the cultivars Racioppella, Guglia, Pizzulella, Oliva amara, and Racioppa as the richest in health-promoting phenolic compounds. Furthermore, it showed a significant variability among the different cultivars, suggesting the possibility of using metabolic fingerprinting approaches for cultivar differentiation, once that further studies aimed at assessing the influence of growing conditions and environmental factors on the chemical profiles of single cultivars are carried out.

High-Resolution Magic Angle Spinning (HR-MAS) NMR-Based Fingerprints Determination in the Medicinal Plant Berberis laurina

Berberis laurina (Berberidaceae) is a well-known medicinal plant used in traditional medicine since ancient times; however, it is scarcely studied to a large-scale fingerprint. This work presents a broad-range fingerprints determination through high-resolution magical angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, a well-established flexible analytical method and one of most powerful "omics" platforms. It had been intended to describe a large range of chemical compositions in all plant parts. Beyond that, HR-MAS NMR allowed the direct investigation of botanical material (leaves, stems, and roots) in their natural, unaltered states, preventing molecular changes. The study revealed 17 metabolites, including caffeic acid, and berberine, a remarkable alkaloid from the genus Berberis L. The metabolic pattern changes of the leaves in the course of time were found to be seasonally dependent, probably due to the variability of seasonal and environmental trends. This metabolites overview is of great importance in understanding plant (bio)chemistry and mediating plant survival and is influenceable by interacting environmental means. Moreover, the study will be helpful in medicinal purposes, health sciences, crop evaluations, and genetic and biotechnological research.

NMR-Based Plant Metabolomics in Nutraceutical Research: An Overview

Few topics are able to channel the interest of researchers, the public, and industries, like nutraceuticals. The ever-increasing demand of new compounds or new sources of known active compounds, along with the need of a better knowledge about their effectiveness, mode of action, safety, etc., led to a significant effort towards the development of analytical approaches able to answer the many questions related to this topic. Therefore, the application of cutting edges approaches to this area has been observed. Among these approaches, metabolomics is a key player. Herewith, the applications of NMR-based metabolomics to nutraceutical research are discussed: after a brief overview of the analytical workflow, the use of NMR-based metabolomics to the search for new compounds or new sources of known nutraceuticals are reviewed. Then, possible applications for quality control and nutraceutical optimization are suggested. Finally, the use of NMR-based metabolomics to study the impact of nutraceuticals on human metabolism is discussed.

Metabolite Profiling of Commiphora wightii (Guggul) with Respect to Seasons

Aim of the study was to undertake comprehensive metabolic profiling of plant parts of Commiphora wightii during two contrasting seasons i.e. summer and winter; compared seasonal metabolic variations; and assess antioxidant activity of fractions for commercial applications. Leaves, young stems and gum-resin extracts from summer and winter seasons were analyzed using GC-MS, HPLC and NMR spectroscopy. The antioxidant activity on each set was determined by DPPH free radical scavenging assay. Complete metabolic profiling from two contrasting seasons identified one hundred and four major known and unknown metabolites. Also, two alkylated phenols, 2,4-di- tert-butyl phenol and 3-(3,5-di- tert-butyl-4-hydroxyphenyl) propanoic acid not reported earlier from this taxon were isolated from the vegetative part. Comparative analysis of seasonal metabolic profiles of leaves, young stems and gum-resin revealed significant variations in concentrations of several metabolites. Multivariate principal component analysis (PCA) showed significant qualitative and quantitative variations in the polar (glycine, quinic acid and myo-inositol) and non-polar metabolites (alkylated phenols, guggulsterones and α-tocopherol) between the two seasons. Variation amongst metabolites such as myo-inositol, quinic acid α- tocopherol and alkylated phenols that are important for nutraceutical industry in the two contrasting seasons is a useful finding. These metabolites are of medicinal and nutraceutical importance and are commonly used in nutraceuticals and dietary supplement industry. DPPH radical scavenging activity (IC50 values) of polar and non-polar extracts varied significantly between summer and winter seasons. The antioxidant activity can be attributed to major polar metabolite, quinic acid biosynthesized in excess during winter, and to non-polar metabolites like alkylated phenols and α-tocopherol present during the summer season. The study shall be useful for medicinal, nutraceutical and dietary supplement industry for selection of polar or non-polar extracts from a particular season for obtaining targeted products with optimized functionality.