Identification of QTLs Controlling α-Glucosidase Inhibitory Activity in Pepper (Capsicum annuum L.) Leaf and Fruit Using Genotyping-by-Sequencing Analysis

Abstract

Diabetes mellitus, a group of metabolic disorders characterized by hyperglycemia, is one of the most serious and common diseases around the world and is associated with major complications such as diabetic neuropathy, retinopathy, and cardiovascular diseases. A widely used treatment for non-insulin-dependent diabetes is α-glucosidase inhibitors (AGIs) such as acarbose, which hinders hydrolytic cleavage of disaccharides and retard glucose absorption. The ability to inhibit α-glucosidase activity has been reported in leaf and fruit of pepper (Capsicum annuum L.). In this study, we aimed to identify quantitative trait loci (QTLs) controlling α-glucosidase inhibitory activity (AGI activity) in pepper leaf and fruit using enzyme assay and genotyping-by-sequencing (GBS) analysis. The AGI activity at three stages of leaf and one stage of fruit development was analyzed by 96 F2 individuals. GBS analysis identified 17,427 SNPs that were subjected to pepper genetic linkage map construction. The map, consisting of 763 SNPs, contained 12 linkage groups with a total genetic distance of 2379 cM. QTL analysis revealed seven QTLs (qAGI1.1, qAGI11.1, qAGI5.1, qAGI9.1, qAGI12.1, qAGI5.2, and qAGI12.2) controlling AGI activity in pepper leaf and fruit. The QTLs for AGI activity varied by plant age and organ. This QTL information is expected to provide a significant contribution to developing pepper varieties with high AGI activity.

Identification of α-Glucosidase Inhibitors from Leaf Extract of Pepper (Capsicum spp.) through Metabolomic Analysis

“…This result agrees with previous studies on pepper and other plant samples. Pepper leaves harvested at different stages i.e., April, July, and October were found to show an average of 36.18%, 66.61%, and 47.29% AGI activities, respectively [66]. Similarly, Kim et al reported that leaves extracts of pepper exhibited 61.1% α-glucosidase inhibition [24].…”

In Vitro Inhibitory Effects of Some Antiviral, Antidiabetic, and Non-Steroidal Anti-Inflammatory Drug Active Compounds on α-Glucosidase and Myeloperoxidase Activities

“…In recent years, in addition to different sugar-based inhibitory molecules being designed (24), extracts obtained from different parts of various plants have also been reported to exhibit inhibitory activity against glucosidase (25)(26)(27). Most of the ɑglucosidase inhibitors in these plants are secondary metabolites such as alkaloids, phenolic acids, flavonoids, terpenoids, anthocyanins, and their glycosides, and these have been suggested to have much stronger inhibitory potentials than the inhibitory effect obtained from acarbose (28).…”

Genetics and breeding of phenolic content in tomato, eggplant and pepper fruits

“…Moreover, 15 eQTLs for flavonoid pathway genes were identified: (i) eQTLs for CHS-1, CHS-2, CHI-2 and FLS co-localized on P01 and overlapped with a mQTL for naringenin chalcone, eQTLs for CHS-1, CHS-2, CHI-1, CHI-2 and FS-2 colocalized with a naringenin chalcone mQTL on P09, (iii) eQTLs for F3'H-1 and F3'H-4, and F3H were detected on P03, P04 and P08, respectively (Wahyuni et al, 2014) (Table 1; Supplementary Data S2). In a study aimed at identifying QTLs associated with aglucosidase inhibitory activity of flavonoids and other compounds present in pepper leaves and fruits (Park et al, 2020), the authors found a QTL on chromosome 9, which co-located with the cluster of mQTLs and eQTLs identified by Wahyuni et al (2014). In a recent work, Wu et al ( 2022) used a F 2 population, resulting from the cross between the flavonoid-contrasting C. annuum accessions Long Sweet (P12) and AC2212 (P24), to identify a major QTL (fc5.1) controlling the accumulation of chalcones, flavonols and flavones located at 228 Mbp on pepper chromosome 5.…”