Mango (Mangifera indica L.), a fruit with sensorial attractiveness and extraordinary nutritional and phytochemical composition, is one of the most consumed tropical varieties in the world. A growing body of evidence suggests that their bioactive composition differentiates them from other fruits, with mango pulp being an especially rich and diverse source of polyphenols. In this study, mango pulp polyphenols were submitted to in vitro gastrointestinal digestion and colonic fermentation, and aliquots were analyzed by HPLC-HRMS. The main phenolic compounds identified in the mango pulp were hydroxybenzoic acid-hexoside, two mono-galloyl-glucoside isomers and vanillic acid. The release of total polyphenols increased after the in vitro digestion, with an overall bioaccessibility of 206.3%. Specifically, the most bioaccessible mango polyphenols were gallic acid, 3-O-methylgallic acid, two hydroxybenzoic acid hexosides, methyl gallate, 3,4-dihydroxybenzoic acid and benzoic acid, which potentially cross the small intestine reaching the colon for fermentation by the resident microbiota. After 48 h of fecal fermentation, the main resultant mango catabolites were pyrogallol, gallic and 3,4-dihydroxybenzoic acids. This highlighted the extensive transformation of mango pulp polyphenols through the gastrointestinal tract and by the resident gut microbiota, with the resultant formation of mainly simple phenolics, which can be considered as biomarkers of the colonic metabolism of mango.

Black carrot has been attracting increasing thanks to its high bioactive compound content. This study presents the polyphenol bio-accessibility of black carrot and two derived products (black carrot snack (BC snack) and black carrot seasoning (BC seasoning)) after in vitro gastrointestinal digestion and colonic fermentation. Additionally, antioxidant activity was measured by 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays. Nine flavonoids and eight anthocyanins were determined by ultra high-performance liquid chromatography high resolution mass spectrometry (UHPLC-HRMS) analysis, the predominant compounds being the hydroxycinnamic acids 3-O-feruloylquinic acid, 4-O-feruloylquinic acid and chlorogenic acid. The BC snack (108 µmol/g DW) presented the highest total polyphenol content, followed by BC seasoning (53 µmol/g DW) and black carrot (11.4 µmol/g DW). The main polyphenols still bio-accessible after in vitro digestion were the hydroxycinnamic acids, with mean recovery rates of 113 % for black carrot, 69% for BC snack and 81% for BC seasoning. The incubation of black carrot and its derived products with human faecal bacterial resulted in the complete degradation of anthocyanins and in the formation of mainly 3-(4′-hydroxyphenyl)propanoic acid as the major catabolic event. In conclusion, our results suggest that the black carrot matrix impacts significantly affects the bio-accessibility of polyphenols and, therefore, their potential health benefits.

Strawberries ( Fragaria sp.) are cherished for their organoleptic properties and nutritional value. However, breeding new cultivars involves the simultaneous selection of many agronomic and fruit quality traits, including fruit firmness and extended postharvest life. The strawberry germplasm collection here studied exhibited extensive phenotypic variation in 26 agronomic and fruit quality traits across three consecutive seasons. Phenotypic correlations and principal component analysis revealed relationships among traits and accessions, emphasizing the impact of plant breeding on fruit weight and firmness to the detriment of sugar or vitamin C content. Genetic diversity analysis on 124 accessions using 44,408 markers denoted a population structure divided into six subpopulations still retaining considerable diversity. Genome‐wide association studies for the 26 traits unveiled 121 significant marker‐trait associations distributed across 95 quantitative trait loci (QTLs). Multiple associations were detected for fruit firmness, a key breeding target, including a prominent locus on chromosome 6A. The candidate gene FaPG1 , controlling fruit softening and postharvest shelf life, was identified within this QTL region. Differential expression of FaPG1 confirmed its role as the primary contributor to natural variation in fruit firmness. A kompetitive allele‐specific PCR assay based on the single nucleotide polymorphism (SNP) AX‐184242253, associated with the 6A QTL, predicts a substantial increase in fruit firmness, validating its utility for marker‐assisted selection. In essence, this comprehensive study provides insights into the phenotypic and genetic landscape of the strawberry collection and lays a robust foundation for propelling the development of superior strawberry cultivars through precision breeding.

Pigments, mainly anthocyanins and carotenoids, are important contributors to fruits’ visual appearance and nutritional properties. In strawberry ( Fragaria spp.), the genetic and molecular mechanisms regulating fruit carotenoid biosynthesis and its natural variation remain largely unexplored. In this study, we sought to identify genomic loci contributing to variation in yellow flesh pigmentation. A major QTL, qYellow Flesh-4B , accounting for 82% of the total phenotypic variation was identified on F . × ananassa chromosome 4B. Following a candidate gene approach, we determined that CCD4(4B), a carotenoid cleavage dioxygenase (CCD), was the underlying gene. Specific polymorphisms on CCD4(4B) promoter region were associated with the yellow flesh phenotype and with differential regulation of CCD4(4B) expression during fruit ripening. Furthermore, CCD4(4B) expression levels were negatively correlated with violaxanthin, lutein, zeaxanthin, β-carotene and total carotenoid content. The role of CCD4(4B) in carotenoid turnover was confirmed by transient overexpression in F. × ananassa fruits, which led to a decrease in carotenoid accumulation. Notably, a −35 C>T SNP identified in CCD4(4B) promoter was found to be predictive for CCD4(4B) expression, and carotenoid content in fruits of a diverse germplasm collection, which included different octoploid Fragaria species. Taken together, these results provide important genetic insights into the natural variation of carotenoid content in strawberry. The High-Resolution Melting (HRM) DNA test here developed offers a fast and reliable method to predict high fruit carotenoid content, representing a useful tool for breeding projects aiming to enhance the nutritional value of this crop.

Strawberries are cherished for their organoleptic properties and nutritional value. However, breeding new cultivars involves the simultaneous selection of many agronomical and fruit quality traits. The strawberry germplasm collection here studied exhibited extensive phenotypic variation in 26 agronomic and fruit quality traits across three consecutive seasons. Phenotypic correlations and Principal Component Analysis (PCA) revealed relationships among traits and accessions, emphasizing the impact of plant breeding. Genetic diversity analysis on 124 accessions using 44,408 markers denoted a population structure divided into six subpopulations that still retain considerable diversity. Genome-wide association studies (GWAS) for the 26 traits unveiled 121 significant marker-trait associations distributed across 95 quantitative trait loci (QTL). Multiple associations were detected for fruit firmness, a key breeding target, including a prominent locus on chromosome 6A. The candidate gene FaPG1, controlling fruit softening, was identified within this QTL region. Differential expression of FaPG1 confirmed its role as the main contributor to natural variation in fruit firmness. A Kompetitive Allele-Specific PCR (KASP) assay based on SNP AX-184242253, associated with the 6A QTL, predicts a substantial increase in fruit firmness, validating its utility for Marker-Assisted Selection (MAS). In essence, this comprehensive study provides insights into the phenotypic and genetic landscape of the strawberry collection and lays a robust foundation for propelling the development of superior strawberry cultivars through precision breeding. Highlight: Several QTL controlling agronomic and fruit quality traits detected by genome wide association studies. Natural variation on FaPG1 expression is associated with a mayor and stable QTL for fruit firmness.

Fruit flavor and aroma are influenced by the sugars-to-acid ratio and most importantly by the specific profile and abundance of volatile organic compounds (VOCs). While over 550 VOCs have been identified in strawberry fruit, fewer than 20 are believed to be key for aroma, being esters the major components. A major and stable quantitative trait locus (QTL) explaining a large percentage (40%) of phenotypic variation for several medium-chain esters (MCE) was mapped at about 19 Mb in chromosome 6A using both a biparental population and genome-wide association studies (GWAS). Using a combination of genetic mapping, global transcriptomic studies of bulked contrasting lines, and in vivo and in silico functional analyses, we identified the cinnamoyl Co-A reductase FaCCR1(6A) and the organic cation/carnitine transporter FaOCT4(6A) as underlying genes. Subcellular localization experiments indicated that FaCCR1(6A) and FaOCT4(6A) localize at the cytosol and tonoplast membrane respectively. Transient overexpression of FaCCR1(6A) and FaOCT4(6A) in fruits resulted in a significant increase in MCE content. Despite the well-described function of CCRs in the biosynthesis of monolignols, in vitro enzymatic assays and molecular docking revealed that FaCCR1(6A) also presents high affinity for MCE precursors, indicating a previously unidentified function of this protein in volatile biosynthesis. Based in our findings, we have developed a predictive KASP assay in FaOCT4(6A) for selecting superior cultivars with enhanced fruit aroma.