Transcriptomic analysis in Anemone flaccida rhizomes reveals ancillary pathway for triterpene saponins biosynthesis and differential responsiveness to phytohormones / 中国天然药物

Anemone flaccida Fr. Schmidt is a perennial medicinal herb that contains pentacyclic triterpenoid saponins as the major bioactive constituents. In China, the rhizomes are used as treatments for a variety of ailments including arthritis. However, yields of the saponins are low, and little is known about the plant's genetic background or phytohormonal responsiveness. Using one-quarter of the 454 pyrosequencing information from the Roche GS FLX Titanium platform, we performed a transcriptomic analysis to identify 157 genes putatively encoding 26 enzymes involved in the synthesis of the bioactive compounds. It was revealed that there are two biosynthetic pathways of triterpene saponins in A. flaccida. One pathway depends on β-amyrin synthase and is similar to that found in other plants. The second, subsidiary ("backburner") pathway is catalyzed by camelliol C synthase and yields β-amyrin as minor byproduct. Both pathways used cytochrome P450-dependent monooxygenases (CYPs) and family 1 uridine diphosphate glycosyltransferases (UGTs) to modify the triterpenoid backbone. The expression of CYPs and UGTs were quite different in roots treated with the phytohormones methyl jasmonate, salicylic acid and indole-3-acetic acid. This study provides the first large-scale transcriptional dataset for the biosynthetic pathways of triterpene saponins and their phytohormonal responsiveness in the genus Anemone.

Health Effects of Small Volatile Compounds from East Asian Medicinal Mushrooms

Medicinal fungi, taken whole or as various forms of extracts, have been used to alleviate, cure or prevent human ailments since pre-historic times. In particular, Asian cultures have incorporated a variety of mushrooms into their medical practices. Chemically pure, bioactive metabolites from fungi have been a mainstay of modern pharmacological research and in addition to antibiotics, include anticancer agents, immunosuppressants, enzyme inhibitors, antagonist and agonists of hormones, and a variety of psychotropic substances. However, to date not many studies have focused on the possible health benefits of odorant volatile organic compounds (i.e., gas phase compounds). An analysis of these compounds for their health related effects will expand the range of compounds available for the treatment of chronic and acute diseases. This review highlights phenolic acids and monoterpenes from Asian medicinal mushrooms (AMMs), which not only produce pleasant odors but also have antioxidant and antibacterial effects. Odorant bioactive volatile phase compounds from medicinal mushrooms remain an essentially untapped source for future medicines, and AMMs remain a promising resource for future pharmacological research.