Activity of tall fescue alkaloids and analogues in in vitro rumen fermentation

Abstract

The alkaloid perloline inhibited rumen fermentation in vitro at 0.04 to 1.0 mM as measured by cellulose digestion. The perlolidine moiety of perloline also inhibited cellulose digestion, but the inhibitory effect of perlolidine was equal to that of perloline only at the higher concentrations. Perloline methyl ether was less inhibitory than perlolidine. The veratrole moiety of perloline and perlolyrine did not inhibit cellulose digestion below 10 mM. Phenanthridine inhibited cellulose digestion at 0.1 to 1.0 mM; however, phenanthridone, 4-(2'-amino)phenyl-2-pyridone, and 4-(2'-formylamino)phenyl-2-pyridone did not inhibit in vitro rumen fermentation. Associated with inhibition of cellulose digestion was a decreased production of volatile fatty acids and bacterial protein production. Biological activity of these substances was greatly influenced by the substitution at the C-5 position of perloline.

BOARD-INVITED REVIEW: St. Anthony's Fire in livestock: Causes, mechanisms, and potential solutions1,2

“…The chemistry and synthesis of ergot alkaloids has been discussed in several publications over the years (Berde, 1980;Weber, 1980;Garner et al, 1993;Smith and Shappell, 2002;Hafner et al, 2008;Bush and Fannin, 2009), including the 1978 publication of the book titled Ergot Alkaloids and Related Compounds (Berde and Stürmer, 1978). Therefore, only a brief synopsis of ergot alkaloid chemistry is provided here for the convenience of the reader.…”

“…There are 3 major classes of ergot alkaloids: 1) clavine alkaloids, 2) lysergic acid and derivatives, and 3) ergopeptine alkaloids ( Figure 1; Lyons et al, 1986;Porter, 1995;Bush and Fannin, 2009). Whereas derivatives of D-lysergic acid (e.g., ergopeptines) are of concern for causing ergotism or fescue toxicosis, those of its epimer, D-isolysergic acid, have little biological effect reported in animal systems (Berde and Stürmer, 1978;Berde, 1980).…”

“…For example, it has been established that the lohne alkaloids (1-aminopyrrollizidine), which are found in endophyteinfested tall fesctie, can inhibit celltilose degradation by ruminai microorganisms (Bush et al, 1976). The impact of the ergot alkaloids on ruminai microbial ecology is less clear.…”

“…Ergot alkaloids ( Figure 1) are naturally occurring mycotoxins (Bush and Fannin, 2009) produced by fungi, including members of the Claviceps (external spore-producing fungi) and Neotyphodium. (endophytic fungi that grow within a plant-without sporulation) genera.…”

Biomass production by fescue and switchgrass alone and in mixed swards with legumes. Final project report

“…In addition to being a Lolium-Festuca amphiploid (Buckner et al, 1985), Johnstone does not contain the fungal endophyte (Acremonium coenophialum Morgan-Jones Gams) present in KY31 and most other tall fescue cultivars (Collins, 1991). Tall fescue containing the endophyte produces high concentrations of several alkaloids (Bush et al, 1976) that have significant physiological activity on ruminants consuming the grass. These alkaloids catalyze thiaminase activity leading to the breakdown of thiamine, an essential growth factor for many microorganisms and for most vertebrates.…”