title: Effects of condensed tannin fractions of different molecular weights from a Leucaena leucocephala hybrid on in vitro methane production and rumen fermentation.
abstract: BACKGROUND
  Molecular weights (MWs) and their chemical structures are the primary factors determining the influence of condensed tannins (CTs) on animal nutrition and methane (CH4 ) production in ruminants. In this study the MWs of five CT fractions from Leucaena leucocephala hybrid-Rendang (LLR) were determined and the CT fractions were investigated for their effects on CH4 production and rumen fermentation.
  
  
  RESULTS
  The number-average molecular weight (Mn ) of fraction F1 (1265.8 Da), which was eluted first, was the highest, followed by those of fractions F2 (1028.6 Da), F3 (652.2 Da), F4 (562.2 Da) and F5 (469.6 Da). The total gas (mL g(-1) dry matter (DM)) and CH4 production decreased significantly (P < 0.05) with increasing MWs of the CT fractions, but there were no significant (P > 0.05) differences between the CT fractions and control on DM degradation. However, the in vitro N disappearance decreased significantly (P < 0.05) with the inclusion of CT fraction F1 (highest MW) compared with the control and other fractions (F2-F5). The inclusion of CT fraction F1 also significantly decreased (P < 0.05) total volatile fatty acid and acetic acid concentrations compared with the control. The acetic/propionic acid ratio was significantly decreased (P < 0.05) by fraction F1 but not by the control and other fractions (F2-F5).
  
  
  CONCLUSIONS
  The CT fractions of different MWs from LLR could affect rumen fermentation and CH4 production, and the impact was more pronounced for the CT fraction with a higher MW.
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Mookiah
authors.initials: M
authors.lastname: Saminathan
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.|Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Chin Chin
authors.initials: CC
authors.lastname: Sieo
authors.affiliation: Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.|Institute of Tropical Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Norhani
authors.initials: N
authors.lastname: Abdullah
authors.affiliation: Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia.
authors.forename: Clemente Michael Vui Ling
authors.initials: CM
authors.lastname: Wong
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: Yin Wan
authors.initials: YW
authors.lastname: Ho
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000821:Animal Feed / Q000032:analysis*; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle; D004032:Diet; D004063:Digestion; D007887:Fabaceae / Q000737:chemistry*; D005232:Fatty Acids, Volatile / Q000096:biosynthesis; D005285:Fermentation; D008697:Methane / Q000096:biosynthesis*; D008970:Molecular Weight; D011422:Propionates / Q000378:metabolism; D012417:Rumen / Q000378:metabolism*; D013634:Tannins / Q000737:chemistry*
chemical_list: D005232:Fatty Acids, Volatile; D011422:Propionates; D013634:Tannins; C029658:propionic acid; D008697:Methane; D019342:Acetic Acid
keywords: Leucaena leucocephala hybrid-Rendang; condensed tannin fractions; methane; molecular weight; volatile fatty acids