Identification of Compounds with Potential Therapeutic Uses from Sweet Pepper (Capsicum annuum L.) Fruits and Their Modulation by Nitric Oxide (NO)

Abstract

Plant species are precursors of a wide variety of secondary metabolites that, besides being useful for themselves, can also be used by humans for their consumption and economic benefit. Pepper (Capsicum annuum L.) fruit is not only a common food and spice source, it also stands out for containing high amounts of antioxidants (such as vitamins C and A), polyphenols and capsaicinoids. Particular attention has been paid to capsaicin, whose anti-inflammatory, antiproliferative and analgesic activities have been reported in the literature. Due to the potential interest in pepper metabolites for human use, in this project, we carried out an investigation to identify new bioactive compounds of this crop. To achieve this, we applied a metabolomic approach, using an HPLC (high-performance liquid chromatography) separative technique coupled to metabolite identification by high resolution mass spectrometry (HRMS). After chromatographic analysis and data processing against metabolic databases, 12 differential bioactive compounds were identified in sweet pepper fruits, including quercetin and its derivatives, L-tryptophan, phytosphingosin, FAD, gingerglycolipid A, tetrahydropentoxylin, blumenol C glucoside, colnelenic acid and capsoside A. The abundance of these metabolites varied depending on the ripening stage of the fruits, either immature green or ripe red. We also studied the variation of these 12 metabolites upon treatment with exogenous nitric oxide (NO), a free radical gas involved in a good number of physiological processes in higher plants such as germination, growth, flowering, senescence, and fruit ripening, among others. Overall, it was found that the content of the analyzed metabolites depended on the ripening stage and on the presence of NO. The metabolic pattern followed by quercetin and its derivatives, as a consequence of the ripening stage and NO treatment, was also corroborated by transcriptomic analysis of genes involved in the synthesis of these compounds. This opens new research perspectives on the pepper fruit’s bioactive compounds with nutraceutical potentiality, where biotechnological strategies can be applied for optimizing the level of these beneficial compounds.

Bell Peppers (Capsicum annum L.) Losses and Wastes: Source for Food and Pharmaceutical Applications

“…Additionally, the presence of gallic acid has been reported in purple (1200 µg/g) and dark violet (1150 µg/g) bell peppers [ 35 ]. These compounds exert potent antioxidant activity against reactive oxygen species and reactive nitrogen species [ 36 ].…”

“…Other bioactive compounds such as colneleic acid, capsoside A, gingerglycolipid A, and blumenol C glucoside have been qualitatively identified in red and yellow bell pepper fruits [ 36 ]. Stuliff et al [ 31 ] reported 57 glycerolipids and glycerophospholipids, two sphingomyelin compounds and ceramides in green, yellow, and red bell peppers.…”

Metabolomic Analysis Identifies Differences Between Wild and Domesticated Chili Pepper Fruits During Development (Capsicum annuum L.)

“…Capsicum annuum is one of the most important horticultural crops worldwide ( Qin et al, 2014 ; Guevara et al, 2021 ; Martínez-Ispizua et al, 2021 ). Belonging to the Solanaceae family, originated and putatively domesticated from Capsicum annuum L. var.…”

Peroxisomal Proteome Mining of Sweet Pepper (Capsicum annuum L.) Fruit Ripening Through Whole Isobaric Tags for Relative and Absolute Quantitation Analysis

“…During ripening, pepper fruits undergo drastic biochemical and phenotypical changes, being the color shift from green to red the most evident since chloroplasts are transformed into chromoplasts as a consequence of the chlorophyll degradation and the biosynthesis of carotenoids, xanthophylls, and anthocyanins. In previous studies, it has been analyzed the sweet pepper fruit ripening at biochemical and molecular levels including the transcriptome ( González-Gordo et al, 2019 ), as well as the metabolism of NADPH-generating enzymes ( Mateos et al, 2009 ; Muñoz-Vargas et al, 2018 , 2020 ), ROS metabolism ( Rodríguez-Ruiz et al, 2017a , 2019 ; Chu-Puga et al, 2019 ; González-Gordo et al, 2020 , 2022a ; Palma et al, 2020a ), reactive nitrogen species ( Chaki et al, 2015 ; Rodríguez-Ruiz et al, 2017b ), the metabolome ( Guevara et al, 2021 ), and the plastidial and mitochondrial proteomes ( Rödiger et al, 2021 ; González-Gordo et al, 2022b ). However, little is known about the proteome from peroxisomes and how it can be modulated during ripening.…”