A New Ceramide from the Ascomycete Tuber indicum

A new C-18 phytosphingosine derivative (1) was isolated from the fruiting bodies of Tuber indicum. Its structure was established as (2S,3S,4R,2′R)-2-N-(2′-hydroxytricosanoyl)-octadecan-1,3,4-triol by spectral and chemical methods.     

Novel Cerebrosides Isolated from the Fermentation Mycelia of Tuber indicum

The four new cerebrosides 1 – 4 possessing a unique C₁₈ 9‐methylsphinga‐4,8‐dienine‐related moiety and a cyclic octapeptide, 5 , possessing alternating proline and glycine moietes were isolated from the Tuber indicum fermentation mycelium. Their structures were established on the basis of a spectroscopic analysis including NMR and HR‐ESI‐MS, as well as an acidic methanolysis experiment. To the best of our knowledge, the cerebrosides identified in the present study are quite different from those isolated from Tuber indicum fruiting bodies. Additionally, it was the first time that a cyclic peptide was isolated from the Tuber genus.     

道地山药红外指纹图谱和聚类分析的鉴别研究

运用模式识别技术的SIMCA法对不同产地的45种山药样品进行了道地性与非道地性的模式识别方法学研究。凭借红外光谱具有的指纹特性,构建山药样品的红外指纹图谱,作为模式识别提取的特征数据,以随机分取的22个样品为训练集,剩余23个样品为试验集,该方法的正确识别率为70％,取得了满意的分类效果。     

Rapid molecular typing of <Emphasis Type="Italic">Tuber melanosporum</Emphasis>, <Emphasis Type="Italic">T. brumale</Emphasis> and <Emphasis Type="Italic">T. indicum</Emphasis> from tree seedlings and canned truffles

We have developed new DNA extraction and purification procedures for investigation of mycorrhized seedlings and canned truffles. Use of these procedures on approximately 100 mg initial material enabled good sample representation. For mycorrhized seedlings, Taq polymerase inhibitors were discarded irrespective of tree species. In routine analysis we systematically used consensus primers ITS1/ITS4 to check the absence of Taq polymerase inhibitors and the presence of fungus DNA. Positive response with ITS validates other positive or negative PCR results. Absence of amplification with ITS prevents validation of other results. For canned truffles, DNA harvested from ascocarps sterilized for one and a half hours at 115°C was amplified with specific primers. We have developed consensus primers, named R12/F12, to check for the presence of amplifiable fungus DNA and the absence of Taq polymerase inhibitors. Here also, positive response with consensus R12/F12 validates other positive or negative PCR results. We have developed one primer pair specific for T. brumale and another specific for T. melanosporum. We can then characterize these two taxa, which enables the use of truffle or truffled French designations. We can also characterize T. indicum, the Asiatic black truffle that might fraudulently be sold as T. melanosporum and T. brumale. These three specific primer pairs were used independently of DNA extraction from tree seedlings or canned truffles. Our process is specific, sensitive, convenient, and quick.J.P. Douet and D. Mabru have contributed equally to this work     

Crystallization and Preliminary Crystallographic Analysis of β-Trichosanthin, an Isoform of Trichosanthin from the Root Tuber of Trichosanthe kirilowii

β-Trichosanthin, a type 1 ribosome-inactivating protein (RIP) isolated from the root tuber of Trichosanthe kirilowii Maxim, is an isoform of trichosanthin. Here we report its crystal- lization in two crystal forms using the hanging-drop vapor-diffusion method. The form A and form B crystals belong to the orthorhombic space group P212121 and monoclinic space group P21, respectively. X-ray data have been collected to 1.6 and 1.2 (A) resolution for form A and form B crystals, respectively, using a synchrotron source.     

中药滴水珠中Neoechinulin A的分离及测定

采用柱色谱法对中药滴水珠中的有效成分Neoechinulin A进行分离纯化,运用现代波谱技术进行结构鉴定,采用反相高效液相色谱法测定其含量。色谱条件: Diamonsil C18柱(250 mm×4.6 mm,5 μm),流动相为甲醇-0.1%磷酸溶液(体积比为63:37),流速为1.0 mL/min,柱温为30 ℃,检测波长为225 nm,进样量为10 μL。结果表明,Neoechinulin A的质量浓度在2.0～40.0 mg/L范围内与其峰面积有良好的线性关系(r0.9995);方法的加样回收率为98.3%～101.1%。该方法简便、快速、准确,可作为中药滴水珠质量控制的一个有效方法。     

Antioxidant Profile and Biosafety of White Truffle Mycelial Products Obtained by Solid-State Fermentation

Solid-state fermentation may produce therapeutic compounds with higher biomass or better product characteristics than those generated by submerged fermentation. The objectives of this study were to analyze the antioxidant activities and biosafety of products obtained by white truffle (Tuber magnatum) solid-state fermentation in media with different ratios of soybean and red adlay. High levels of antioxidant components and high antioxidant activities such as DPPH radical scavenging, ferrous ion chelation, and reducing power were measured in 20 mg/mL water and ethanol extracts of the white truffle fermentation products. When the solid-state fermentation medium contained soybean and red adlay in a 1:3 ratio (S1A3), the fermentation product had more uniform antioxidant compositions and activities by principal component analysis (PCA). In addition, a 200 ppm water extract of the mycelial fermentation product was able to protect zebrafish embryos from oxidative stress induced by 5 mM hydrogen peroxide. Sprague–Dawley rats were fed the mycelial fermentation product for 90 consecutive days, revealing a no-observed-adverse-effect level (NOAEL) of 3000 mg/kg BW/day. Therefore, mycelial products obtained by white truffle solid-state fermentation can be used instead of expensive fruiting bodies as a good source of antioxidant ingredients.