title: Bioactive fractions from the pasture legume Biserrula pelecinus L. have an anti-methanogenic effect against key rumen methanogens.
abstract: Methanogenic archaea (methanogens) are common inhabitants of the mammalian intestinal tract. In ruminants, they are responsible for producing abundant amounts of methane during digestion of food, but selected bioactive plants and compounds may inhibit this activity. Recently, we have identified that, Biserrula pelecinus L. (biserrula) is one such plant and the current study investigated the specific anti-methanogenic activity of the plant. Bioassay-guided extraction and fractionation, coupled with in vitro fermentation batch culture were used to select the most bioactive fractions of biserrula. The four fractions were then tested against five species of methanogens grown in pure culture. Fraction bioactivity was assessed by measuring methane production and amplification of the methanogen mcrA gene. Treatments that showed bioactivity were subcultured in fresh broth without the bioactive fraction to distinguish between static and cidal effects. All four fractions were active against pure cultures, but the F2 fraction was the most consistent inhibitor of both methane production and cell growth, affecting four species of methanogens and also producing equivocal-cidal effects on the methanogens. Other fractions had selective activity affecting only some methanogens, or reducing either methane production or methanogenic cell growth. In conclusion, the anti-methanogenic activity of biserrula can be linked to compounds contained in selected bioactive fractions, with the F2 fraction strongly affecting key rumen methanogens. Further study is required to identify the specific plant compounds in biserrula that are responsible for the anti-methanogenic activity. These findings will help devise novel strategies to control methanogen populations and activity in the rumen, and consequently contribute in reducing greenhouse gas emissions from ruminants.
authors.affiliation: Centre for Plant Genetics and Breeding, School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia. Electronic address: bidhyut.banik@research.uwa.edu.au.
authors.forename: Bidhyut K
authors.initials: BK
authors.lastname: Banik
authors.affiliation: School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
authors.forename: Zoey
authors.initials: Z
authors.lastname: Durmic
authors.affiliation: Centre for Plant Genetics and Breeding, School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
authors.forename: William
authors.initials: W
authors.lastname: Erskine
authors.affiliation: Centre for Plant Genetics and Breeding, School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Department of Agriculture and Food Western Australia, Livestock Industries, 3 Baron-Hay Court, South Perth, WA 6151, Australia.
authors.forename: Clinton K
authors.initials: CK
authors.lastname: Revell
authors.affiliation: School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
authors.forename: Joy
authors.initials: J
authors.lastname: Vadhanabhuti
authors.affiliation: CSIRO Livestock Industries, Queensland Bioscience Precinct, St Lucia, Qld, Australia.
authors.forename: Christopher S
authors.initials: CS
authors.lastname: McSweeney
authors.affiliation: CSIRO Livestock Industries, Queensland Bioscience Precinct, St Lucia, Qld, Australia.
authors.forename: Jagadish
authors.initials: J
authors.lastname: Padmanabha
authors.affiliation: School of Chemistry and Biochemistry, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
authors.forename: Gavin R
authors.initials: GR
authors.lastname: Flematti
authors.affiliation: School of Chemistry and Biochemistry, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
authors.forename: Azizah A
authors.initials: AA
authors.lastname: Algreiby
authors.affiliation: School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
authors.forename: Philip E
authors.initials: PE
authors.lastname: Vercoe
mesh_terms: D000818:Animals; D061249:Batch Cell Culture Techniques; D002417:Cattle; D005591:Chemical Fractionation / Q000379:methods; D003470:Culture Media / Q000737:chemistry; D019605:Euryarchaeota / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D007887:Fabaceae / Q000737:chemistry*; D005285:Fermentation / Q000187:drug effects; D008697:Methane / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D012417:Rumen / Q000382:microbiology
chemical_list: D003470:Culture Media; D010936:Plant Extracts; D008697:Methane
keywords: Bioactivity; Biserrula pelecinus L.; Methane; Methanogens; Pure culture