Biomechanics of isolated tomato (Solanum lycopersicum) fruit cuticles during ripening: the role of flavonoids

Abstract

Flavonoids accumulate in tomato (Solanum lycopersicum L.) fruit cuticles during ripening. Their quantitative contribution to the biomechanical properties of the cuticle is studied in six tomato genotypes which show presence or absence of these compounds at the red ripe stage of fruit development. Tomato cuticles with flavonoids at red ripe showed a dramatic increase of these compounds between mature green and red ripe stages together with a significant increase in the elastic modulus. On the other hand, cuticles without flavonoids displayed a similar biomechanical behaviour at mature green and red ripe stages. The absence of flavonoids could also be related with a predominance of the viscoelastic performance of the cuticle. Thus, the increase of phenolics in tomato fruit cuticles during ripening is correlated with a more rigid cutin network that reinforces the mechanical function of polysaccharides which tend to diminish at this stage due to cell wall disassembly. A role of phenolics as biomechanical modulators of the cuticle behaviour is proposed.

Characterization of a New Pink-Fruited Tomato Mutant Results in the Identification of a Null Allele of the SlMYB12 Transcription Factor

“…Since flavonols are important for fruit cuticle biomechanics and postharvest behavior (Domínguez et al, 2009a(Domínguez et al, , 2011Lara et al, 2014), we investigated whether some of the genes differentially expressed in the Dy mutants might be involved in cuticle development. Of these 267 genes, we identified a set of 18 in the biosynthesis of cutin monomers, cuticular waxes (i.e.…”

“…There is interest in flavonoids due to their effect on fruit appearance and their nutritional and healthrelated properties (Rein et al, 2006;Butelli et al, 2008;Luo et al, 2008;Martin et al, 2011). In tomato fruit, they have also been reported to contribute to correct cuticle function as they affect its rigidity and susceptibility to cracking and, consequently, postharvest behavior (Domínguez et al, 2009a(Domínguez et al, , 2011Lara et al, 2014). Increasing the accumulation, or compositional diversity, of polyphenol species, including flavonoids, to improve fruit nutritional value and tolerance to environmental stress, is an important goal of biotechnology and breeding Zhang et al, 2015).…”

“…Fruits from homozygous plants that contain the recessive "y" allele in the y locus in chromosome 1 failed to accumulate the yellow flavonoid precursor, naringenin chalcone, in the fruit peel, resulting in a pink-colored fruit phenotype (Lindstrom, 1925;Rick and Butler, 1956;Adato et al, 2009;Ballester et al, 2010). Flavonoids are class of phenolic compounds that have a broad range of ecological and physiological functions (Winkel-Shirley, 2001;Grotewold, 2006;Domínguez et al, 2009aDomínguez et al, , 2009bDomínguez et al, , 2011 and are widely distributed in the plant kingdom (Domínguez et al, 2011). There is interest in flavonoids due to their effect on fruit appearance and their nutritional and healthrelated properties (Rein et al, 2006;Butelli et al, 2008;Luo et al, 2008;Martin et al, 2011).…”

CHSsilencing suggests a negative cross-talk between wax and flavonoid pathways in tomato fruit cuticle

“…2 Incorporation of flavonoids was postulated to modify the cuticle's mechanical properties by increasing its resistance to deformation. 3 Thus, during the period of organ expansion, the cuticle can be deformed with little stress applied. 2 CHALCONE SYNTHASE (CHS) is the enzyme responsible for the synthesis of chalconaringenin, the flavonoid mainly accumulated in tomato fruit cuticle and responsible for its orange-yellow color.…”

Transcriptional Activity of the MADS Box ARLEQUIN/TOMATO AGAMOUS-LIKE1 Gene Is Required for Cuticle Development of Tomato Fruit

“…The degree of invagination and the relative contribution of each cuticle component affect its biomechanical behavior as well as the physiological properties of the wholefruit pericarp (Matas et al, 2004;López-Casado et al, 2007;Domínguez et al, 2011;España et al, 2014b). Thus, waxes and flavonoids have been shown to act as fillers stiffening the cuticle (Petracek and Bukovac, 1995;Domínguez et al, 2009). On the other hand, cutin is responsible for the viscoelastic behavior and polysaccharides contribute to the elastic phase (López-Casado et al, 2007, Domínguez et al, 2011.…”