Search results
Results from the WOW.Com Content Network
Pyrrolizidine alkaloids (PAs), sometimes referred to as necine bases, are a group of naturally occurring alkaloids based on the structure of pyrrolizidine. Their use dates back centuries and is intertwined with the discovery, understanding, and eventual recognition of their toxicity on humans and animals.
Pyrrolizidine is a heterocyclic organic compound. Formally, it is a saturated derivative of pyrrolizine. Pyrrolizidine forms the central chemical structure of a variety of alkaloids known collectively as pyrrolizidine alkaloids. [1] It is one of five classes of iminosugars. These are often synthesized from a carbohydrate. [2]
Pages in category "Pyrrolizidine alkaloids" The following 12 pages are in this category, out of 12 total. This list may not reflect recent changes. ...
Like other pyrrolizidine alkaloids, senecionine is toxic when ingested. The ingested molecule is a protoxin that is metabolized to its active form. [3] In large quantities, ingestion can lead to critical illness, including convulsions and death. Studies in rodents have shown an LD 50 of 65 mg/kg. [4]
Another group of alkaloids, the senecio-type alkaloids, are produced by various plants and like the lolines, the senecio alkaloids possess a pyrrolizidine ring structure. Unlike the lolines, however, the senecio alkaloids exhibit strong hepatotoxicity, [13] owing to a double bond between C-1 and C-2 in their ring structure. [13]
Alkaloids with partial pyrrolidine structure are usually sub-categorized based on their occurrence and biogenetic origin. Hygrin and cuscohygrin were isolated from the leaves of the coca shrub, [2] while (-)-codonopsinine was isolated from the woodland vine tiger bell.
Pyrrolizidine alkaloidosis poisoning in the United States has remained moderately rare among humans. The most common reports are the outcome of the misuse of medicinal home remedies, or the alkaloids are present in food and drink substances such as milk and honey when the animal carriers were exposed to the toxins.
Legonmycins are a group of chemical compounds that belong to the pyrrolizidine family of naturally occurring alkaloids.Discovered by a joint team of researchers from University of Ghana, University of Aberdeen, and Wuhan University, the compounds were isolated from Streptomyces microorganisms in Legon, a suburb of Accra, Ghana.