Natural sources, i.e. fungal strains and species producing ergot alkaloids (EA), are surveyed together with the chemical structures of EA and a list of new natural EA discovered in the last three decades. Other topics include new efficient chromatographic methods (HPLC) for the separation and isolation of new natural EA and also immunological methods of EA detection.

Ergot alkaloids--sources, structures and analytical methods.

Biosynthesis of ergot alkaloids and related compounds

The European Food Safety Authority (EFSA) was asked by the European Commission to deliver a scientific opinion on ergot alkaloids (EAs) in food and feed. EAs are produced by several members within the fungal orders of Hypocreales and Eurotiales. In Europe, Claviceps purpurea is the most widespread Claviceps species within the Hypocreales. A total of 20 558 analytical results for EAs in 1 716 food, 496 feed and 67 unprocessed grain samples were considered in this opinion. Based on the EAs identified in sclerotia of C. purpurea, and recent literature data, the EFSA Panel on Contaminants in the Food Chain (CONTAM Panel) based its risk assessment on the main C. purpurea EAs, namely ergometrine, ergotamine, ergosine, ergocristine, ergocryptine (which is a mixture of a- and s- isomers), ergocornine, and the corresponding –inine epimers. The CONTAM Panel performed estimates of both chronic and acute exposure for various age groups across European countries. A BMDL10 of 0.33 mg/kg b.w. per day was calculated for the incidence of tail muscular atrophy in a 13-week rat feeding study of ergotamine. This effect was considered representative of the vasoconstrictive effects of EAs and provided a suitable reference point for establishment of a group acute reference dose of 1 µg/kg body weight (b.w.) and a group tolerable daily intake of 0.6 µg/kg b.w. per day. The Panel concluded that whilst the available data do not indicate a concern for any population subgroup, the dietary exposure estimates relate to a limited number of food groups and a possible unknown contribution from other foods cannot be discounted. Estimates of exposure for livestock based on example diets and levels of EAs in cereal grains reported suggest that under normal conditions the risk of toxicosis is low.

Scientific Opinion on Ergot alkaloids in food and feed

https://www.cell.com/cell-chemical-biology/pdf/S1074-5521(03)00266-7.pdf

Molecular Cloning and Analysis of the Ergopeptine Assembly System in the Ergot Fungus Claviceps purpurea

(±)-Lysergic acid (1) has been synthesized from 4-hydroxymethyl-1-tosylindole (2) by a sequence of 9 steps. The crucial thermolysis 9 10 involves the in situ-generation of the transient diene III which undergoes an intramolecular cycloaddition to a C, N-double bond at 200° and at low stationary concentration of III.

Total Synthesis of (±)-Lysergic Acid by an Intramolecular Imino-Diels-Alder Reaction. Preliminary communication

Aus Paspalurn-Mutterkorn, das von zahlreichen, uber die ganze Erde verteilten Fundorten beschafft worden war, konnten mehrere Hundert Stamme isoliert und unter geeigneten Standardbedingungen in Submerskultur gezuchtet werden. Auf Grund der Zusammensetzung des von den untersuchten Stammen produzierten Al- kaloidgemisches, liessen sich drei «chemische Rassen» H definieren. Zur ersten, weit- verbreiteten Rasse gehoren 98°%yo aller untersuchten Stamme. Ihr sind auch die bereits bekannten Claviceps-paspali-stamme von CHAIN, TONOLO et al. [7] [8] und von GROGER et al. [9] zuzuordnen. Als Hauptalkaloide finden sich hier das Amid und das Methylcarbinolamid der Lysergsaure (IIa, b) und der Isolysergsaure (IIIa, b). Bei der zweiten, in Argentinien gefundenen, neuen Rasse bestehen 75 bis 80°% yo aller Alkaloide aus Ergobasin IIc und Ergobasinin IIIc. Die dritte, ebenfalls neue chemische Rasse, die bisher nur in Portugal gefunden wurde, bildet ein Gemisch fast ausschliesslich amphoterer Produkte, das neben Lysergsaure (I)zu uber 70% aus der bisher unbekannten 6-Methyl-Δ8,9-ergolen-8-carbonsaure (IV) besteht.

6‐Methyl‐Δ8,9‐ergolen‐8‐carbonsäure, ein neues Ergolinderivat aus Kulturen eines Stammes von Claviceps paspali STEVENSet HALL. 60. Mitteilung über Mutterkornalkaloide

J. Rutschmann

Papers

6‐Methyl‐Δ8,9‐ergolen‐8‐carbonsäure, ein neues Ergolinderivat aus Kulturen eines Stammes von Claviceps paspali STEVENSet HALL. 60. Mitteilung über Mutterkornalkaloide