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• Mbidde bananas show distinct metabolite profile linked to unfavourable sensory properties. • Metabolites associated with sour, sweet, and bitter taste are increased in Mbidde bananas. • Mbidde and Matooke bananas can be defined by distinct metabolites. • Matooke, Mchare and plantains display differential regulation of phenylpropanoid formation. • Metabolomics can contribute to breeding bananas with better consumer quality. Breeding programs for disease resistant bananas in Sub-Saharan Africa generated resistant bananas, which did not meet fruit quality characteristics preferred by consumers. The present study aimed to establish chemotypes underlying preferred cooking bananas of Matooke, Mchare and plantain and less preferred Mbidde bananas, used for beer brewing. The metabolite data of Mbidde showed higher levels of metabolites associated with sour, sweet, and astringent taste; as well as different textural properties associated with cell wall composition and lignin content. Significant differences in the majority of specialised and primary metabolites were observed in the pulp of cooking banana groups. Analysis of peel tissue indicated similar metabolic differences in the protective layer surrounding the pulp and suggested a distinct genetic regulation of phenylpropanoid and flavonoid pathways between the genome groups. In summary, the present data can be used to establish metabolic traits associated with consumer preference, which can augment modern breeding programs. [ABSTRACT FROM AUTHOR]

Vitamin A deficiency (VAD) in Low and Medium Income countries remains a major health concern. Ipomoea batatas, orange sweet potato (OSP), is one of the biofortification solutions being implemented by the World Health Organisation (WHO) to combat VAD. However, high provitamin A (β-carotene) content has been associated with a reduction in dry matter, reducing calorific value and having adverse effects on consumer traits. Both starch and carotenoid formation are located in amyloplasts and could potentially compete for the same precursors. Hence, five different sweet potato storage root phenotypes were characterized through spatial metabolomics and proteomics at the sub-plastidal level. The metabolite data suggested an indirect correlation of starch and carotenoids through the TCA cycle and pentose phosphate pathway. Furthermore, a change in lipid composition was observed to accommodate the storage of carotenoids in the hydrophilic environment of the amyloplast. The data suggests an alteration of cellular ultra-structures and perturbation of metabolism in high β-carotene producing sweet potato roots. This corroborates with previous gene expression analysis through biochemical analysis of sweet potato root tissue. Interaction between carotenoid and starch biosynthesis in sweet potato amyloplasts. [Display omitted] • Starch and carotenoids compete for the same metabolite precursors. • Reduction of starch is indirectly linked to carotenoids through pyruvate biosynthesis. • Presence of carotenoids changes the cellular ultra-structures of the plastid. • All membrane structures in the root plastid are derived from the plastid envelope. • Functions of membrane structures include synthesis, transport and storage of carotenoids. [ABSTRACT FROM AUTHOR]

Dwindling fossil fuel reserves and poor environmental credentials of chemical synthesis means, new renewable sources for the production and manufacture of valuable chemicals and pharmaceuticals are required. Presently, tobacco is an underutilised non-food crop with the potential to act as a biofactory. In this study, metabolite profiling across vegetative development has been carried out to provide a quantitative baseline of metabolites, their formation and interaction. Two tobacco platforms have been used, Nicotiana benthamiana and Nicotiana tabacum. Our data generated has provided the quantitative and qualitative baseline levels for exploitable pathways and metabolites, across two complementary Nicotiana species. N. benthamiana is the chassis of choice for transient expression. The metabolite data obtained for N. benthamiana highlighted that before flower emergence, the increased central carbon metabolism and high amino acid levels are available for the biosynthesis of endogenous or heterologous metabolites. In the future, engineering pathways or biocatalysts into N. benthamiana could add value to the process presently used to produce low volume, high cost pharmaceuticals. Similar outputs were obtained for N. tabacum, which has the advantage of providing a large biomass and hence, high product yield. These data provide an insight into the metabolite pools available in tobacco for future exploitation by emerging New Plant Breeding Techniques. • Qualitative and quantitative baselines for N. benthamiana and N. tabacum metabolites. • Increased central carbon metabolism and amino acids occur prior to flowering. • Nicotine levels are associated with development of reproductive organs. • Unlike N. benthamiana, total polyphenol levels fluctuate during N. tabacum development. [ABSTRACT FROM AUTHOR]

Over the previous decades, biotechnological innovations have led to improved agricultural productivity, more nutritious foods and lower chemical usage. Both in western societies and Low Medium Income Countries (LMICs). However, the projected increases in the global population, means the production of nutritious food stuffs must increase dramatically. Building on existing genetic modification technologies a series of New Plant Breeding Technologies (NPBT) has recently emerged. These approaches include, Agro-infiltration, grafting, cis and intragenesis and gene editing technologies. How these new techniques should be regulated has fostered considerable debate. Concerns have also been raised, to ensure over-regulation does not arise, creating administrative and economic burden. In this article the existing landscape of genetically modified crops is reviewed and the potential of several New Plant Breeding Techniques (NPBT) described. Metabolomics is an omic technology that has developed in a concurrent manner with biotechnological advances in plant breeding. There is potentially further opportunities to advance our metabolomic technologies to characterise the outputs of New Plant Breeding Technologies, in a manner that is beneficial both from an academic, biosafety and industrial perspective. [ABSTRACT FROM AUTHOR]

Strawberries (Fragaria × ananassa Duch.) are one of the most economically important fruit crops worldwide, several commercially viable cultivars are cultivated in the northern region of Thailand. The morphological characters at the young vegetative seedling stage can be very similar, which has hindered breeding efforts. The present study assesses the ability of random amplification of polymorphic DNA (RAPD) markers and metabolomics techniques to distinguish six strawberry cultivars. Both techniques showed congruent results for the leaf tissue and classified the cultivars into three major clusters. For the most different cultivars, Akihime and Praratchatan No.80, fruits were analysed at eight fruit ripening stages. The data highlighted a broad biological variation at the early ripening stages and less biological variation at the mature stages. Key metabolic differences included the polyphenol profile in Praratchatan No.80 and fatty acid synthesis/oxidation in Akihime. In summary, the RAPD and metabolite data can be used to distinguish strawberry cultivars and elucidate the metabolite composition of each phenotype. This approach to the characterisation of genotypes will benefit future breeding programmes. Image 1 • RAPD markers and metabolite profiles of strawberry leaves showed similar clustering. • Strawberry fruit showed high biological variation at green compared to red-ripe stage. • Fruit metabolism varied between Praratchatan No.80 and Akihime during ripening. • Fatty acid metabolism/catabolism of Akihime results in distinct aroma profile. • Praratchatan No.80 has >2-fold higher levels of polyphenols and flavonoids. [ABSTRACT FROM AUTHOR]

Banana (Musa spp.) plants produce many health promoting compounds in leaf, peel and pulp. For a robust metabolic analysis of these tissues, leaf at five developmental stages were compared to assess suitable sampling practices. Results confirmed that the common sampling practise of leaf 3 is applicable for metabolic comparisons. The developed work flow was applied to analyse the metabolite diversity present in 18 different Musa varieties, providing baseline levels of metabolites in leaf, peel and pulp tissue. Correlation analysis was then used to ascertain whether similar trends can be detected in the three plant tissues of the diversity panel. The genome group displayed a dominant role in the composition of the metabolome in all three tissues. This led to the conclusion that a correlation between tissues was only possible within a genome group as the different parental backgrounds caused too great a variation in the metabolomes. It also suggests the metabolome could be used to monitor the interaction/hybridisation of genomes during breeding programmes. Image 1 • Leaf three is most representative of varietal metabolic composition. • Score plots of leaf, peel and pulp showed common varietal groupings. • Main differences between banana pulps included TCA cycle intermediates and sugars. • Metabolite composition of pulp showed no correlation to consumption type. [ABSTRACT FROM AUTHOR]

A broad diversity of phenotypes are available within the cassava germplasm collections. The phenotypes include improved nutritional, starch or culinary root quality as well as abiotic and biotic resistance properties. Some of these traits can be found naturally occurring in cassava landraces, whereas others are the result of targeted breeding efforts. For future breeding programmes it is important to know the underlying mechanisms of these desirable traits. Metabolomics can assist in the elucidation of these mechanisms by measuring the end products of the cellular processes conferring the traits of interest. The present study focused on the comparison of two or more variants of the same trait such as high and low culinary quality or resistance and susceptibility to thrips. Overall, eight different traits were assessed. Results showed that amino acids and umami compounds were associated with superior culinary attributes and the phenylpropanoid superpathway plays an important role in pest resistance. Furthermore, the data highlighted a low chemodiversity in African cassavas and that the source-sink relation was still active at the harvest stage. [ABSTRACT FROM AUTHOR]

Vitamin A deficiency (VAD) is a global health problem, which despite significant financial investments and initiatives has not been eradicated. Biofortification of staple crops with β-carotene (provitamin A) in Low Medium Income Countries (LMICs) is the approach advocated and adopted by the WHO and HarvestPlus programme. The accurate determination of β-carotene is key to the assessment of outputs from these activities. In the present study, HPLC-PDA analysis displayed superior resolving power, separating and identifying 23 carotenoids in the orange sweet potato (Ipomoea batatas) variety used, including only eight carotenoids with provitamin A properties. Additionally, the results evidently displayed that the use of lyophilised material facilitated the extraction of twice the amount of pigments compared to fresh material, which impacts the precise calculation of the provitamin A content. These results highlight that yellow to orange starchy edible crops produce a wide array of carotenoids in addition to β-carotene. Biosynthetically it is clear from the intermediates and products accumulating that the β-branch of the carotenoid pathway persists in sweet potato tuber material. Collectively, the data also have implications with respect to the determination and biosynthesis of provitamin A among staple crops for developing countries. Image 1 • β-carotene quantification by LC is far more accurate than by spectrophotometer. • 23 different carotenoids are detected by HPLC in orange sweet potato. • Only 9 of 23 carotenoids have provitamin A activity. • Sweet potatoes express a wide range of carotenoid epoxides/furanoids. [ABSTRACT FROM AUTHOR]