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Aconitum carmichaelii has long been used as a traditional Chinese medicine, and its processed lateral roots are known commonly as fuzi. Aconitine-type C 19 -diterpenoid alkaloids accumulating in the lateral roots are some of the main toxicants of this species, yet their biosynthesis remains largely unresolved. As a first step towards understanding the biosynthesis of aconitine-type C 19 -diterpenoid alkaloids, we performed de novo transcriptome assembly and analysis of rootstocks and leaf tissues of Aconitum carmichaelii by next-generation sequencing. A total of 525 unigene candidates were identified as involved in the formation of C 19 -diterpenoid alkaloids, including those encoding enzymes in the early steps of diterpenoid alkaloids scaffold biosynthetic pathway, such as ent -copalyl diphosphate synthases, ent -kaurene synthases, kaurene oxidases, cyclases, and key aminotransferases. Furthermore, candidates responsible for decorating of diterpenoid alkaloid skeletons were discovered from transcriptome sequencing of fuzi, such as monooxygenases, methyltransferase, and BAHD acyltransferases. In addition, 645 differentially expressed genes encoding transcription factors potentially related to diterpenoid alkaloids accumulation underground were documented. Subsequent modular domain structure phylogenetics and differential expression analysis led to the identification of BAHD acyltransferases possibly involved in the formation of acetyl and benzoyl esters of diterpenoid alkaloids, associated with the acute toxicity of fuzi. The transcriptome data provide the foundation for future research into the molecular basis for aconitine-type C 19 -diterpenoid alkaloids biosynthesis in A. carmichaelii . [ABSTRACT FROM AUTHOR]

Hypericum species (Hypericaceae) are a group of important plants with medicinal, edible, and ornamental values. A phytochemical study on the whole plants of H. hengshanense W. T. Wang, a species endemic to China, led to the isolation and elucidation of 25 monoterpenoid acylphloroglucinols (MAPs). Among them, 10 are undescribed compounds, namely hyphengshanols A–D, (+)-empetrilatinol A, (−)-empetrilatinol B, (−)-hyperjovinol A, (9 S ,2′ S)-dauphinol F, and (8 R ,2′ S)-empetrikathiforin. In addition, the absolute configurations of other six compounds were firstly determined in the current study. The structures were established by ultraviolet (UV), high resolution electrospray ionization mass spectrum (HR-ESI-MS), and nuclear magnetic resonance spectroscopy (NMR) data. The absolute configurations were determined by experimental and calculated electronic circular dichroism (ECD) data analyses. Cytotoxicity assays on five human cell lines HL-60, A549, SMMC-7721, MDA-MB-231, and SW480 revealed that 16 compounds exhibited broad-spectrum antiproliferative activities with IC 50 ranging from 7.54 to 45.70 μM. Ten undescribed monoterpenoid acylphloroglucinols and 15 known analogs were isolated and identified, including six pairs of stereoisomers. Their cytotoxicity against five cancer cell lines was evaluated. [Display omitted] • MAPs were isolated from Hypericum hengshanense including 10 undescribed ones. • The absolute configurations of 16 MAPs were determined by ECD calculations. • Six pairs of stereoisomers were separated via chiral-phase HPLC. • Sixteen isolates showed cytotoxicity against five cancer cell lines. [ABSTRACT FROM AUTHOR]

Crop domestication is often accompanied by changes in metabolite compositions that alter traits such as flavor, color, or other beneficial properties. Fruits of eggplants ( Solanum melongena L.) and related species are abundant and diverse in pharmacologically interesting phenolic compounds, particularly hydroxycinnamic acid (HCA) conjugates such as the antioxidant caffeoylquinic acids (CQA) and HCA-polyamine amides (HCAA). To understand metabolite variability through the lens of natural and artificial selection, HPLC-DAD was used to generate phenolic profiles for 32 compounds in fruits from 93 accessions representing 9 Solanum species. Profiles were used for identification of species-level and infraspecific chemical patterns across both genetic distance and landscape. Sampling of plant lines included the undomesticated progenitor of eggplant and Asian landraces with a genetic background associated with three Asian regions near proposed separate centers of domestication to test whether chemical changes were convergent despite different origins. Results showed ten compounds were unique to species, and ten other compounds varied significantly in abundance among species. Five CQAs and three HCA-polyamine conjugates were more abundant in wild (undomesticated) versus domesticated eggplant, indicating that artificial selection may have led to reduced phenolic levels. No chemical abundance patterns were associated with site-origin. However, one genetically distinct lineage of geographically-restricted SE Asian eggplants ( S. melongena subsp. ovigerum ) had a higher HCAA content and diversity than other lineages, which is suggested to be related to artificial selection for small, firm fruit. Overall, patterns show that fruit size, palatability and texture were preferentially selected over health-beneficial phytochemical content during domestication of several nightshade crops. [ABSTRACT FROM AUTHOR]

Eight compounds including four caffeoyl phenylpropanoid glycosides, jasnervosides A–D ( 1 – 4 ), one monoterpenoid glycoside, jasnervoside E ( 5 ), and three secoiridoid glycosides, jasnervosides F–H ( 10 – 12 ), were isolated from the stems of Jasminum nervosum Lour. (Oleaceae), along with four known compounds, poliumoside ( 6 ), verbascoside ( 7 ), α- l -rhamnopyranosyl-(1→3)- O -(α- l -rhamnopyranosyl(1→6)-1- O - E -caffeoyl-β- d -glucopyranoside ( 8 ), and jaspolyanthoside ( 9 ). Their structures were elucidated on the basis of their physicochemical and spectroscopic properties. Compounds 1 , 2 , 4 and 11 displayed potent antioxidant activities in the DPPH assay, while 2 and 3 displayed good activities against LPS-induced TNF-α and IL-1β production in BV2 cells. Compounds 1 – 5 and 10 – 12 were evaluated for their cytotoxic activities against three human cancer cell lines (A-549, Bel-7402, and HCT-8), but none displayed significant activity. [ABSTRACT FROM AUTHOR]

Abstract: The extract of Tripterygium wilfordii Hook F. (TwHF), which showed anti-inflammatory and immunosuppressive activities in human clinical trials for rheumatoid arthritis, was subjected to the activity-guided fractionation and spectroscopic characterization of bioactives. A tetrahydrofuran lignan, tripterygiol (1), and eight known compounds, all capable of suppressing pro-inflammatory gene expression were identified. Most of the pharmacological activity of the extract can be attributed to triptolide, its most abundant and active component, with some contribution from tripdiolide. [Copyright &y& Elsevier]

Abstract: An ethanolic extract of Artemisia dracunculus L. having antidiabetic activity was examined as a possible aldose reductase (ALR2) inhibitor, a key enzyme involved in diabetic complications. At 3.75μg/mL, the total extract inhibited ALR2 activity by 40%, while quercitrin, a known ALR2 inhibitor, inhibited its activity by 54%. Bioactivity guided fractionation and isolation of the compounds that inhibit ALR2 activity was carried out with the total ethanolic extract yielding four bioactive compounds with ALR2 inhibitory activity ranging from 58% to 77% at 3.75μg/mL. Using LC/MS, 1H NMR, 13C NMR and 2D NMR spectroscopic analyses, the four compounds were identified as 4,5-di-O-caffeoylquinic acid, davidigenin, 6-demethoxycapillarisin and 2′,4′-dihydroxy-4-methoxydihydrochalcone. This is the first report on their isolation from A. dracunculus and the ALR2 inhibitory activity of 4,5-di-O-caffeoylquinic acid, 6-demethoxycapillarisin and 2′,4′-dihydroxy-4-methoxydihydrochalcone. These results suggest a use of the extract of A. dracunculus for ameliorating diabetic complications. [Copyright &y& Elsevier]