RESUMEN
Flavonoids, a class of phenolic compounds, are one of the main functional components and have a wide range of molecular structures and biological activities in Polygonatum. A few of them, including homoisoflavonoids, chalcones, isoflavones, and flavones, were identified in Polygonatum and displayed a wide range of powerful biological activities, such as anti-cancer, anti-viral, and blood sugar regulation. However, few studies have systematically been published on the flavonoid biosynthesis pathway in Polygonatum cyrtonema Hua. Therefore, in the present study, a combined transcriptome and metabolome analysis was performed on the leaf, stem, rhizome, and root tissues of P. cyrtonema to uncover the synthesis pathway of flavonoids and to identify key regulatory genes. Flavonoid-targeted metabolomics detected a total of 65 active substances from four different tissues, among which 49 substances were first study to identify in Polygonatum, and 38 substances were flavonoids. A total of 19 differentially accumulated metabolites (DAMs) (five flavonols, three flavones, two dihydrochalcones, two flavanones, one flavanol, five phenylpropanoids, and one coumarin) were finally screened by KEGG enrichment analysis. Transcriptome analysis indicated that a total of 222 unigenes encoding 28 enzymes were annotated into three flavonoid biosynthesis pathways, which were "phenylpropanoid biosynthesis", "flavonoid biosynthesis", and "flavone and flavonol biosynthesis". The combined analysis of the metabolome and transcriptome revealed that 37 differentially expressed genes (DEGs) encoding 11 enzymes (C4H, PAL, 4CL, CHS, CHI, F3H, DFR, LAR, ANR, FNS, FLS) and 19 DAMs were more likely to be regulated in the flavonoid biosynthesis pathway. The expression of 11 DEGs was validated by qRT-PCR, resulting in good agreement with the RNA-Seq. Our studies provide a theoretical basis for further elucidating the flavonoid biosynthesis pathway in Polygonatum.
Asunto(s)
Vías Biosintéticas , Flavonoides , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Metabolómica , Polygonatum , Transcriptoma , Flavonoides/biosíntesis , Flavonoides/metabolismo , Flavonoides/genética , Polygonatum/genética , Polygonatum/metabolismo , Polygonatum/química , Metabolómica/métodos , Vías Biosintéticas/genética , Perfilación de la Expresión Génica/métodos , MetabolomaRESUMEN
Polygonatum cyrtonema Hua, an edible resource and medical material, is mainly consumed as a food in China. However, few published studies have comprehensively assessed its nutritional components. In this study, the proximate, carbohydrate, and dietary fiber contents as well as the mineral, vitamin, and amino acid compositions of five sources of P. cyrtomena grown in Yuhang district, Hangzhou city, Zhejiang province, were investigated. The nutritional profile of the five germplasms was investigated using analytical chemistry methods. All germplasms had a low starch content and contained greater amounts of carbohydrates (23.25-34.29%), protein (2.96-5.40%), Ca (195.08-282.08 mg/100 g), Fe (29.68-59.37 mg/100 g), and vitamin C (60.49-149.86 mg/100 g) in comparison to ginger, yam, and potatoes. The polysaccharide content ranged from 16.92% to 28.48%, representing the main source of carbohydrates. Fructose, a desirable sweetener, was the most abundant monosaccharide, representing 1.06% to 4.88% of the content. P. cyrtonema was found to be high in dietary fiber, with pectin and resistant starch being the major soluble components and hemicellulose being the dominant insoluble dietary fiber. A correlation analysis (CA) revealed significant correlations for the carbohydrate components and dietary fiber fractions with other nutrients. A principal component analysis (PCA) identified significant differences between the nutritional characteristics of the five germplasms, with Huanggang having the highest comprehensive quality scores. Moreover, ten nutrient components were selected as potential indicators that could be used to further evaluate the nutritional quality of P. cyrtomena. Our results demonstrate the rich nutrient composition and characteristics of P. cyrtonema and provide a valuable reference for the future development and utilization of Polygonatum.
RESUMEN
This article marks the first report on high-performance liquid chromatography (HPLC) coupled with diode-array detection (DAD) and quadruple time-of-flight mass spectrometry (Q-TOF/MS) for the identification and quantification of main bioactive constituents in Baeckea frutescens. In total, 24 compounds were identified or tentatively characterised based on their retention behaviours, UV profiles and MS fragment information. Furthermore, a validated method with good linearity, sensitivity, precision, stability, repeatability and accuracy was successfully applied for simultaneous determination of five flavonoids and one chromone in different plant parts of B. frutescens collected at different harvest times, and their dynamic contents revealed the appropriate harvest times. The established HPLC-DAD-Q-TOF/MS using multi-bioactive markers was proved to be a validated strategy for the quality evaluation on both raw materials and related products of B. frutescens.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromonas/análisis , Flavonoides/análisis , Myrtaceae/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Estructura Molecular , Reproducibilidad de los ResultadosRESUMEN
Baeckea frutescens is an aromatic shrub used in South China as an ornamental and as a spice. Four unusual C-methylated biflavonoids named baeckeins F-I (1-4) were isolated from the roots of B. frutescens. The baeckeins F-I possessed a unique carbon skeleton, a flavonol conjugated with a coumaronochromone molecule via the unusual linkages of C-2-C-8 and C-3-O-C-7. Their structures were elucidated by analysis of the 1D ((1)H/(13)C) and 2D NMR (HSQC/HMBC/NOESY) and HR-ESI-MS spectroscopic data, and the absolute stereochemistry for chiral carbons of C-2 and C-3 was established by CD spectrometry combined with quantum chemical calculations. Baeckeins F-I (1-4) were also evaluated for their anti-inflammatory activities by detecting the NO production of LPS-induced RAW264.7 murine macrophage cell line; baeckein I (4) with the ß-d-glucose unit and configuration of (2R,3R) exhibited the highest NO inhibitory activity (IC50=15.2 µM), which was similar to that of the positive control indomethacin.
Asunto(s)
Antiinflamatorios/farmacología , Biflavonoides/farmacología , Medicamentos Herbarios Chinos/farmacología , Myrtaceae/química , Raíces de Plantas/química , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Biflavonoides/química , Biflavonoides/aislamiento & purificación , Línea Celular , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Estructura MolecularRESUMEN
A phytochemical study of Baeckea frutescens afforded a new biflavonoid named as baeckein E (1), along with four known C-methylated flavonols, baeckeins A (2) and B (3), 6-methylquercetin (6) and 6-methylquercetin-4'-O-ß-D-glucopyranoside (7), and two known biflavonoids baeckeins C (4) and D (5). The structure of compound 1 was elucidated on the basis of spectroscopic analysis, including HR-ESI-MS, 1D and 2D NMR spectra, and the absolute configurations of C-2 and C-3 for compound 1 were assigned by circular dichroism spectrometry combined with quantum chemical calculations. The antioxidant and cytoprotective activities of compounds 1-7 were also investigated.