1H NMR-based metabolomics and UHPLC-ESI-MS/MS for the investigation of bioactive compounds from Lupinus albus fractions

Metabolome of different cultivars of peas, lentils, faba beans and lupins - An 1H NMR spectroscopic exploration of their sensory attributes and potential biofunctionality

The transition to a more plant-based diet embraces a higher consumption of diversified pulses. Understanding the chemical composition of pulses is crucial to decipher their biofunctionality. This study analyzed 14 different cultivars of 4 types of pulses (pea, lentil, faba bean, and lupin) using NMR-based metabolomics. Sucrose, glutamate, and citrate were the metabolites representing the most abundant polar chemical classes (carbohydrates, amino acids, and organic acids). Lupin had a higher content of carbohydrates, and a lower content of free amino acids than the other species. Differences among the cultivars related to carbohydrates were found for peas and lentils, which was reflected in variations in their metabolic pathway potential. Faba beans showed highest concentrations of phenolic compounds. Correlation with data from descriptive sensory profiling enabled pinpointing several amino acids and some organic acids that contributed to explain variations in perceived smell and taste among the cultivars.

1H NMR-Based Metabolomics Profile of Green and Red Amaranthus Grown in Open Field versus Greenhouse Cultivation System

Traditionally, indigenous African leafy vegetables such as Amaranthus, blackjack, jute mallow, cleome monophyla, and spider plants have been conventionally and organically grown as weeds in open fields. However, the lack of land space due to the increase in population has resulted in unconventional, modern, and advanced agricultural farming. The introduction of a greenhouse has recently become the second most popular growing system alongside shade net and glasshouse to increase productivity and meet consumers' demand. Several studies on Amaranthus species have solely focused on physiological parameters and nutritional composition, leaving a huge gap on their metabolomic profile of the leaves which is crucial to comprehend when growing Amaranthus species in different cropping systems. Therefore, the study aimed to determine the influence of different cropping systems on the release of metabolites of two commonly consumed Amaranthus species in South Africa. H1 -Nuclear Magnetic Resonance (NMR) tool was used to profile the untargeted metabolites of green (Amaranthus graecizans L.) and red (Amaranthus cruentus L.) species. A total of 12 metabolites-trehalose, betaine, glutamine, choline, sucrose, caprate, adenosine, asparagine, carnitine, caffeine, aspartate, and alanine-were detected in green amaranth grown in open fields. Except for caffeine, aspartate, and caprate, which were found in the green amaranth grown in open fields, all the other metabolites were detected in the greenhouse grown once. Interestingly, allantoin, which serves as an allelochemical, was the sole distinct metabolite detected in greenhouse cultivated green amaranth. On the contrary, seven similar metabolites were quantified in red amaranth grown in both open fields and greenhouses, apart from caffeine, which was only detected in greenhouse-cultivated red amaranth.

Applications of some advanced sequencing, analytical, and computational approaches in medicinal plant research: a review

The potential active chemicals found in medicinal plants, which have long been employed as natural medicines, are abundant. Exploring the genes responsible for producing these compounds has given new insights into medicinal plant research. Previously, the authentication of medicinal plants was done via DNA marker sequencing. With the advancement of sequencing technology, several new techniques like next-generation sequencing, single molecule sequencing, and fourth-generation sequencing have emerged. These techniques enshrined the role of molecular approaches for medicinal plants because all the genes involved in the biosynthesis of medicinal compound(s) could be identified through RNA-seq analysis. In several research insights, transcriptome data have also been used for the identification of biosynthesis pathways. miRNAs in several medicinal plants and their role in the biosynthesis pathway as well as regulation of the disease-causing genes were also identified. In several research articles, an in silico study was also found to be effective in identifying the inhibitory effect of medicinal plant-based compounds against virus' gene(s). The use of advanced analytical methods like spectroscopy and chromatography in metabolite proofing of secondary metabolites has also been reported in several recent research findings. Furthermore, advancement in molecular and analytic methods will give new insight into studying the traditionally important medicinal plants that are still unexplored.

Metabolomics and chemometrics depict the changes in the chemical profile of white lupine (Lupinus albus L.) bioactive metabolites during seed germination

The current study attempts to illustrate how the chemical and biological profile of white lupine seeds varies throughout the course of various germination days using UHPLC-QqQ-MS combined to chemometrics. Abscisic acid showed maximum level in the un-germinated seeds and started to decline with seed germination accompanied by an increase in the levels of gibberellins which were undetectable in un-germinated seeds. Coumaronochromones were the most prevalent constituents detected in un-germinated seeds while day 2 sprouts showed significant accumulation of flavones. The levels of alkaloids showed significant increase upon germination of the seeds reaching its maximum in day 14 sprouts. The OPLS model coefficients plot indicated that lupinalbin D and F, apigenin hexoside, kaempferol hexoside, albine, and hydoxylupanine showed strong positive correlation to the alpha amylase inhibitory activity of the tested samples while lupinalbin A, lupinisoflavone, lupinic acid and multiflorine were positively correlated to the inhibition of alpha glycosidase activity. The results obtained indicated that seed germination has a profound effect on the chemical profile as well as the in-vitro antidiabetic activity of lupine seeds.

Development of an HPLC-MS/MS Method for the Determination of Alkaloids in Lupins

Lupin alkaloids (LAs) represent a class of toxic secondary metabolites in plants, in particular in Lupinus spp.; they are produced as a defense mechanism due to their strong bitter taste and are very dangerous for human and animals. In this work, a sensitive and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analytical method for the identification and quantification of thirteen lupin alkaloids was developed and validated according to FDA guidelines. Efficient extraction and clean-up steps, carried out by solid-phase extraction, were finely tuned on the basis of the characteristics of the analytes and lupin samples, providing good selectivity with minimized matrix interference. The effectiveness of the method was proven by the satisfactory recovery values obtained for most of the analytes and a matrix effect ≤23% for all tested levels. In addition, a sensitive and reliable determination of the target compounds was obtained; LOQs were between 1 and 25 µg Kg^-1, i.e., below the requested maximum levels (<200 mg Kg^-1). The method was applied to evaluate the LAs profile in different batches of raw L. albus L. samples, varying in size and across farming treatments.

Innovative Application of Metabolomics on Bioactive Ingredients of Foods

Metabolomics, as a new omics technology, has been widely accepted by researchers and has shown great potential in the field of nutrition and health in recent years. This review briefly introduces the process of metabolomics analysis, including sample preparation and extraction, derivatization, separation and detection, and data processing. This paper focuses on the application of metabolomics in food-derived bioactive ingredients. For example, metabolomics techniques are used to analyze metabolites in food to find bioactive substances or new metabolites in food materials. Moreover, bioactive substances have been tested in vitro and in vivo, as well as in humans, to investigate the changes of metabolites and the underlying metabolic pathways, among which metabolomics is used to find potential biomarkers and targets. Metabolomics provides a new approach for the prevention and regulation of chronic diseases and the study of the underlying mechanisms. It also provides strong support for the development of functional food or drugs. Although metabolomics has some limitations such as low sensitivity, poor repeatability, and limited detection range, it is developing rapidly in general, and also in the field of nutrition and health. At the end of this paper, we put forward our own insights on the development prospects of metabolomics in the application of bioactive ingredients in food.