Flavonoids, being prevalent in fruits and vegetables, are essential to the diverse stages of plant growth, development, and storage. Furthermore, flavonoids have been shown to exert substantial beneficial effects on human health, prompting heightened scientific interest in their potential advantages. This review elucidates the functions of flavonoids in fruits and vegetables, confirming their position as natural sources of these compounds, despite the differences in type and concentration among various species. This review elucidates the significance of flavonoids in the growth and development of fruits and vegetables, highlighting their roles in enhancing pigmentation and providing protection against both biotic and abiotic stresses. In relation to human health, flavonoids are recognized for their ability to combat aging, mitigate inflammation, safeguard the nervous system, and promote overall well-being. Additionally, this review proposes avenues for future research in the domain of flavonoids, underscoring the necessity for ongoing exploration of their potential applications and benefits.

Lignin is a critical component of the closing layer of the potato (Solanum tuberosum L.) tuber during healing; however, the molecular mechanism of its formation remains poorly understood. To elucidate the molecular mechanism of tuber healing, we screened the genes encoding transcription factors that regulate lignin synthesis(StMYB24/49/105/144/168, StWRKY19/20/22/23/34) and the key genes involved in lignin monomer synthesis (PHENYLALANINE AMMONIA LYASE 5 (StPAL5) and CINNAMYL ALCOHOL DEHYDROGENASE 14 (StCAD14)) for induced expression after wounding using transcriptome data. DLR, Y1H, EMSA, and ChIP-qPCR assays revealed that StMYB168 could bind directly to the StPAL5 and StCAD14 promoters to activate their expression and that StWRKY20 enhanced this regulation with a synergistic effect. Y2H, BiFC, and Co-IP assays showed that StMYB168 interacted with StWRKY20 to form a MYB-WRKY complex. Furthermore, transient overexpression of StMYB168 and StWRKY20 in Nicotiana benthamiana leaves upregulated the expression of NbPAL and NbCAD10 and promoted lignin accumulation in the leaves. In addition, overexpression of StWRKY20 and StMYB168 together resulted in higher expression levels of NbPAL and NbCAD10 and higher levels of lignin monomer and total lignin. In contrast, silencing of StMYB168 and StWRKY20 in potato significantly reduced the lignin content of wounded tubers. In conclusion, StMYB168 and StWRKY20 are important regulators of lignin biosynthesis in potato tubers during healing and can positively regulate lignin biosynthesis by forming a complex. The elucidation of this regulatory module provides information on the regulatory mechanism of lignin monomer synthesis in wounded tubers at the transcriptional level.

This study investigates the effects of soaking fresh-cut potato tubers in 50 µmol/L melatonin (MT) on their quality and antioxidant capacity. MT treatment effectively maintained the tubers’ appearance, leading to higher sensory evaluation scores and increased total soluble solids (TSS) content. Additionally, MT treatment resulted in higher lightness (L*) and blue-yellow chromaticity (b*) values, while reducing red-green chromaticity (a*) values and the browning index. Texture analysis revealed significant improvements in hardness, springiness, cohesiveness, gumminess, chewiness, and resilience of the tubers. Moreover, MT treatment led to increase accumulation of total phenols and flavonoids, enhancing the gene expression and activities of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), while decreasing the activity of polyphenol oxidase (PPO). The treatment also boosted the tubers’ capacity to scavenge 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), ferric ion reducing antioxidant power (FRAP), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS⁺) free radicals, which was directly correlated with the elevated total phenol and flavonoid content. MT can also promote the accumulation of endogenous MT within the tubers and effectively control the proliferation of microorganisms. In conclusion, MT treatment effectively extends the shelf life of fresh-cut potato tubers while enhancing their antioxidant capacity.