Transcriptomic and Metabolic Profiling of High-Temperature Treated Storage Roots Reveals the Mechanism of Saccharification in Sweetpotato (Ipomoea batatas (L.) Lam.)

Abstract

The saccharification of sweetpotato storage roots is a common phenomenon in the cooking process, which determines the edible quality of table use sweetpotato. In the present study, two high saccharified sweetpotato cultivars (Y25, Z13) and one low saccharified cultivar (X27) in two growth periods (S1, S2) were selected as materials to reveal the molecular mechanism of sweetpotato saccharification treated at high temperature by transcriptome sequencing and non-targeted metabolome determination. The results showed that the comprehensive taste score, sweetness, maltose content and starch change of X27 after steaming were significantly lower than those of Y25 and Z13. Through transcriptome sequencing analysis, 1918 and 1520 differentially expressed genes were obtained in the two periods of S1 and S2, respectively. Some saccharification-related transcription factors including MYB families, WRKY families, bHLH families and inhibitors were screened. Metabolic analysis showed that 162 differentially abundant metabolites related to carbohydrate metabolism were significantly enriched in starch and sucrose capitalization pathways. The correlation analysis between transcriptome and metabolome confirmed that the starch and sucrose metabolic pathways were significantly co-annotated, indicating that it is a vitally important metabolic pathway in the process of sweetpotato saccharification. The data obtained in this study can provide valuable resources for follow-up research on sweetpotato saccharification and will provide new insights and theoretical basis for table use sweetpotato breeding in the future.

Comprehensive Evaluation of Raw Eating Quality in 81 Sweet Potato (Ipomoea batatas (L.) Lam) Varieties

“…The raw eating quality of tubers and root crops requires different evaluations. The heating process of tuberous roots affects the starch gradually gelatinizing, leading to the leaching of maltose [13]. Then, the sugar content of sweet potato increases and increases the risk associated with sweet potato consumption for diabetics.…”

“…Raw sweet potatoes have less maltose sugar than those that have undergone heat processing because heating affects the starch's transformation into maltose [12]. Cooked sweet potatoes are higher in sugar, as the heat turns starches into maltose for easier digestion, providing a sweeter flavor than raw sweet potatoes [13]. More sugar increases blood sugar after eating, causing concerns about blood pressure and diabetes [14].…”

Heterologous expression and enzymatic characteristics of sulfatase from Lactobacillus plantarum dy-1

“…Studies have shown that phenolic acids form complexes with the active sites of enzymes through hydrogen bonding and hydrophobic interaction, thus blocking the active sites of enzymes or changing the conformation of enzymes, resulting in a decrease in their catalytic activity. 34,35 Our previous study demonstrated that total polyphenol was significantly elevated after fermentation in LFBE, and that LFBE played a significant role in alleviating obesity and type 2 diabetes in rats caused by a high-fat diet, which indicated that L. p dy-1 fermentation could improve the physiological activity of phenolic acid, especially in the glucose and lipid metabolism. 13 The improvement in the physiological activity due to phenolic acid may be related to the key role of esterase secreted during barley fermentation.…”

Exploring and exploiting genetics and genomics for sweetpotato improvement: Status and perspectives

“…To date, multi-omics studies in sweetpotato are limited. In two recent studies, integration of transcriptomic and metabolomic data facilitated the identification of genes and metabolites involved in anthocyanin accumulation and the mechanism of saccharification in tuberous roots of sweetpotato ( He et al., 2020 ; Li et al., 2021a ). Genome-wide analysis of expression QTLs (eQTLs) has also been applied to sweetpotato and was used to reveal the regulatory architecture of gene expression variation ( Zhang et al., 2020a ; Chen et al., 2021 ).…”