Physico-Chemical Characteristics of Soluble Lignin Fractions Released from Forage Grasses by Ruminant Digestion

Japan Agricultural Research Quarterly
ISSN 00213551
NII recode ID (NCID) AA0068709X
Full text

To analyze the structural modifications of forage grass lignin during digestion in ruminant animals, dioxane-soluble lignin fractions were isolated from the feces and rumen digesta of ruminants that received forage grasses, without any pretreatments such as ultragrinding, acid and alkali hydrolysis, and their physico-chemical characteristics were compared with those of undigested original lignin preparations of forage grasses. Both dioxane-soluble lignin fractions from the feces and rumen digesta were composed mostly of guaiacyl-syringyl lignin with p-hydroxyphenylpropane units and contained only small amounts of non-lignin constituents. When compared with the undigested original lignin preparations, the dioxanesoluble lignin fractions contained a larger amount of syringylpropane units, and a much smaller amount of bound phenolic acids and showed a lower molecular size. Dioxanesoluble lignin fractions from the in vitro rumen-digested residues of forage grass contained a smaller amount of bound phenolic acids and associated carbohydrates and showed a lower molecular size than those from the cellulose-treated residues. These results indicate that soluble lignin fragments, which are likely to be degradation products of grass lignins or lignin-carbohydrate complexes involving bound phenolic acids, are release in the rumen and then excrered in feces.

Date of issued
Creator Tsuneo KONDO Takashi WATANABE Tomoko OHSHITA Tadashi KYUMA
Available Online
NII resource type vocabulary Journal Article
Volume 32
Issue 3
spage 187
epage 195
Language eng

Related Publication