Diversity and evolution of cytochrome P450s of Jacobaea vulgaris and Jacobaea aquatica.

BACKGROUND: Collectively, plants produce a huge variety of secondary metabolites (SMs) which are involved in the adaptation of plants to biotic and abiotic stresses. The most characteristic feature of SMs is their striking inter- and intraspecific chemical diversity. Cytochrome P450 monooxygenases (CYPs) often play an important role in the biosynthesis of SMs and thus in the evolution of chemical diversity. Here we studied the diversity and evolution of CYPs of two Jacobaea species which contain a characteristic group of SMs namely the pyrrolizidine alkaloids (PAs). RESULTS: We retrieved CYPs from RNA-seq data of J. vulgaris and J. aquatica, resulting in 221 and 157 full-length CYP genes, respectively. The analyses of conserved motifs confirmed that Jacobaea CYP proteins share conserved motifs including the heme-binding signature, the PERF motif, the K-helix and the I-helix. KEGG annotation revealed that the CYPs assigned as being SM metabolic pathway genes were all from the CYP71 clan but no CYPs were assigned as being involved in alkaloid pathways. Phylogenetic analyses of full-length CYPs were conducted for the six largest CYP families of Jacobaea (CYP71, CYP76, CYP706, CYP82, CYP93 and CYP72) and were compared with CYPs of two other members of the Asteraceae, Helianthus annuus and Lactuca sativa, and with Arabidopsis thaliana. The phylogenetic trees showed strong lineage specific diversification of CYPs, implying that the evolution of CYPs has been very fast even within the Asteraceae family. Only in the closely related species J. vulgaris and J. aquatica, CYPs were found often in pairs, confirming a close relationship in the evolutionary history. CONCLUSIONS: This study discovered 378 full-length CYPs in Jacobaea species, which can be used for future exploration of their functions, including possible involvement in PA biosynthesis and PA diversity.

α-Glucosidase inhibitory effect and simultaneous quantification of three major flavonoid glycosides in Microctis folium.

Microctis Folium, the leaves of Microcos paniculata L., is a commonly used herbal tea material. The methanol extract of Microctis Folium and its principle compounds vitexin (1), isovitexin (2) and isorhamnetin 3-O-ß-D-rutinoside (3) were investigated for their α-glucosidase inhibitory effects. The extract showed strong α-glucosidase inhibitory effect (IC50 = 61.30 µg/mL) and the three flavonoid glycosides 1-3 exerted satisfactory α-glucosidase inhibitory effects, with IC50 values of 244.0 µM, 266.2 µM and 275.4 µM, respectively. A simple and reliable HPLC-DAD method was developed for the quantification of the three flavonoid glycosides in Microctis Folium and applied successfully to determine contents of these components in samples collected from different locations. This study suggested that Microctis Folium may be a promising candidate for development of herbal antidiabetes drugs, and vitexin, isovitexin and isorhamnetin 3-O-ß-D-rutinoside can be the biomarkers and chemical markers for this plant substance.

Urinary metabolomic profiling reveals difference between two traditional Chinese medicine subtypes of coronary heart disease.

The World Health Organization has shown that coronary heart disease (CHD) is a more common cause of death than cancer. In traditional Chinese medicine (TCM), CHD is classified as a form of thoracic obstruction that can be divided in different subtypes including Qi stagnation with blood stasis (QS) and Qi deficiency with blood stasis (QD). Different treatment strategies are used based on this subtyping. Owing to the lack of scientific markers in the diagnosis of these subtypes, subjective judgments made by clinicians have limited the objective manner for utility of TCM in the treatment of CHD. Untargeted (UHPLC-QTOF-MS) and targeted (UHPLC-MS/MS) metabolomics approaches were employed to search significantly different metabolites related to the QS or QD subtypes of CHD with angina pectoris in this study. A total of 42 metabolites were obtained in the untargeted metabolomics analysis and 34 amino acids were detected in the targeted metabolomics analysis. In total, 16 metabolites were found significantly different among different groups. The results showed distinct metabolic profiles of urine samples not only between CHD patients and healthy controls, but also between the two subtypes of CHD. Pathway analysis of the significantly varied metabolites revealed that there were subtype-related differences in the activity of pathways. Therefore, urinary metabolomics can reveal the pathological changes of CHD in different subtypes, make the diagnosis of CHD in different subtypes in an objective manner and comprehensive and contribute to personalized treatment by providing scientific evidence.

¹H nuclear magnetic resonance based-metabolomic characterization of Peucedani Radix and simultaneous determination of praeruptorin A and praeruptorin B.

As a widely used traditional herbal medicine, it is crucial to characterize the holistic metabolic profile of Peucedani Radix (Chinese name: Qian-hu). However, it is quite arduous to obtain the whole picture of chemical constituents appropriately with the existing analytical techniques that were based on HPLC-UV or LC-MS/MS system. In present investigation, nuclear magnetic resonance (NMR) spectroscopy coupled with principal components analysis (PCA) was introduced to metabolomic characterization of Qian-hu crude extracts without any chromatographic separation. In addition, the contents of praeruptorin A (PA) and proaeruptorin B (PB) in Qian-hu were simultaneously determined using quantitative (1)H NMR (q(1)H NMR) spectroscopy. Eighteen reference compounds (1-18), which were purified from this herbal drug extract previously, were recruited for the assignment of the protonic signals in the (1)H NMR spectra. Following PCA, 15 batches of Peucedani Radix were divided into two groups (I and II), and angular-type pyranocoumarins, in particular PA and PB, as well as 5-methoxycoumarin were demonstrated as the predominant markers being responsible for the distinguishment of Qian-hu from different districts. The contents of the two analytes (PA & PB) were calculated by the relative ratio of the integral values of the target peak for each compound to the known amount of the internal standard, formononetin (IS). The lower limits of quantitation were determined as 19.5µg/mL for both PA and PB. The quantitative results indicated that the contents of PA and PB showed quite variable qualities among different extract samples. Above all, (1)H NMR spectroscopy, that could not only provide comprehensive profiles of the metabolites but also achieve convenient determination of praeruptorin A and praeruptorin B, is a promising means for evaluating the medicinal samples of Peucedani Radix.

Metabolic differentiations of Pueraria lobata and Pueraria thomsonii using ¹H NMR spectroscopy and multivariate statistical analysis.

Puerariae Radix was a widely used herbal medicine. Pueraria lobata (PL) and Pueraria thomsonii (PT) were the two authorized sources of Puerariae Radix (gegen) in China. In this study, metabolic differentiations between these two species were investigated using NMR spectroscopy followed by principal components analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The content of puerarin in PL and PT was also determined using quantitative (1)H NMR spectroscopy. Thirteen isoflavones were tentatively identified based on 1D and 2D NMR spectroscopic data in two species. The (1)H NMR spectra of PL and PT were obviously different. PL and PT could also be markedly discriminated from (1)H NMR spectroscopic data by PCA and PLS-DA. For the crude drug resources, isoflavones, in which puerarin is the most important one, were regarded as the reasonable markers for the discrimination of the two species. The contents of puerarin and total isoflavones in PL were quantitated much higher than those in PT. Above all, (1)H NMR spectroscopy, which can provide comprehensive profiles of the metabolites and achieve convenient determinations of puerarin and total isoflavones in a single run, is an efficient means for evaluating the medicinal samples and achieving a better quality control of Puerariae Radix.