Flavonoid Biosynthesis Genes Putatively Identified in the Aromatic Plant Polygonum minus via Expressed Sequences Tag (EST) Analysis

Abstract

P. minus is an aromatic plant, the leaf of which is widely used as a food additive and in the perfume industry. The leaf also accumulates secondary metabolites that act as active ingredients such as flavonoid. Due to limited genomic and transcriptomic data, the biosynthetic pathway of flavonoids is currently unclear. Identification of candidate genes involved in the flavonoid biosynthetic pathway will significantly contribute to understanding the biosynthesis of active compounds. We have constructed a standard cDNA library from P. minus leaves, and two normalized full-length enriched cDNA libraries were constructed from stem and root organs in order to create a gene resource for the biosynthesis of secondary metabolites, especially flavonoid biosynthesis. Thus, large-scale sequencing of P. minus cDNA libraries identified 4196 expressed sequences tags (ESTs) which were deposited in dbEST in the National Center of Biotechnology Information (NCBI). From the three constructed cDNA libraries, 11 ESTs encoding seven genes were mapped to the flavonoid biosynthetic pathway. Finally, three flavonoid biosynthetic pathway-related ESTs chalcone synthase, CHS (JG745304), flavonol synthase, FLS (JG705819) and leucoanthocyanidin dioxygenase, LDOX (JG745247) were selected for further examination by quantitative RT-PCR (qRT-PCR) in different P. minus organs. Expression was detected in leaf, stem and root. Gene expression studies have been initiated in order to better understand the underlying physiological processes.

Anti-inflammatory effects of Polygonum minus (Huds) extract (Lineminus™) in in-vitro enzyme assays and carrageenan induced paw edema

“…The present study shows that Polygonum minus extract has anti-inflammatory effects that can inhibit both the COX-2 and 5-LOX enzymes. The Polygonum minus has been reported to be rich with flavonoids [ 34 , 35 ]. Flavonoids can interrupt the oxidative generation of AA from phospholipids and reduce the downstream production of inflammatory metabolites from AA metabolism, oxidative damage, and induction of inducible inflammatory pathways due to their potent antioxidant capacity [ 36 ].…”

Exploiting genes and functional diversity of chlorogenic acid and luteolin biosyntheses in Lonicera japonica and their substitutes

“…This study confirmed that the chlorogenic acid and luteolin contents are significantly different between the buds and the leaves of L. japonica. Organ preferential expression of PAL, C4H, 4CL, CHS and CHI (Li et al, 2008;Rani et al, 2012;Roslan et al, 2012) is exhibited in the leaves, stem, and roots. PAL1, PAL2, and PAL4 are related to tissue-specific lignin synthesis in the leaves of A. thaliana (Olsen et al, 2008).…”

Effects of a Proprietary Freeze‐Dried Water Extract of Eurycoma longifolia (Physta) and Polygonum minus on Sexual Performance and Well‐Being in Men: A Randomized, Double‐Blind, Placebo‐Controlled Study

“…It has flavonoid properties and is widely used as a food additive [17]. It has been described to have antioxidant activity, antimicrobial activity, and antiulcer activity [18].…”