title: Modulatory effects of condensed tannin fractions of different molecular weights from a Leucaena leucocephala hybrid on the bovine rumen bacterial community in vitro.
abstract: BACKGROUND
  Condensed tannin (CT) fractions of different molecular weights (MWs) may affect rumen microbial metabolism by altering bacterial diversity. In this study the effects of unfractionated CTs (F0) and five CT fractions (F1-F5) of different MWs (F1, 1265.8 Da; F2, 1028.6 Da; F3, 652.2 Da; F4, 562.2 Da; F5, 469.6 Da) from Leucaena leucocephala hybrid-Rendang (LLR) on the structure and diversity of the rumen bacterial community were investigated in vitro.
  
  
  RESULTS
  Real-time polymerase chain reaction assay showed that the total bacterial population was not significantly (P > 0.05) different among the dietary treatments. Inclusion of higher-MW CT fractions F1 and F2 significantly (P < 0.05) increased the Fibrobacter succinogenes population compared with F0 and CT fractions F3-F5. Although inclusion of F0 and CT fractions (F1-F5) significantly (P < 0.05) decreased the Ruminococcus flavefaciens population, there was no effect on the Ruminococcus albus population when compared with the control (without CTs). High-throughput sequencing of the V3 region of 16S rRNA showed that the relative abundance of genera Prevotella and unclassified Clostridiales was significantly (P < 0.05) decreased, corresponding with increasing MW of CT fractions, whereas cellulolytic bacteria of the genus Fibrobacter were significantly (P < 0.05) increased. Inclusion of higher-MW CT fractions F1 and/or F2 decreased the relative abundance of minor genera such as Ruminococcus, Streptococcus, Clostridium XIVa and Anaeroplasma but increased the relative abundance of Acinetobacter, Treponema, Selenomonas, Succiniclasticum and unclassified Spirochaetales compared with the control and lower-MW CT fractions.
  
  
  CONCLUSIONS
  This study indicates that CT fractions of different MWs may play an important role in altering the structure and diversity of the rumen bacterial community in vitro, and the impact was more pronounced for CT fractions with higher MW. © 2016 Society of Chemical Industry.
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: School of Science, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia.|Monash University Malaysia Genomics Facility, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia.
authors.forename: Han Ming
authors.initials: HM
authors.lastname: Gan
authors.affiliation: Institute of Bioscience, Universiti Putra Malaysia, 43400, UPM Serdang, Selangor, Malaysia.
authors.forename: Sharanya
authors.initials: S
authors.lastname: Ravi
authors.affiliation: Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, UPM Serdang, Selangor, Malaysia.
authors.forename: Karthikkumar
authors.initials: K
authors.lastname: Venkatachalam
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, 88999, 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: D000818:Animals; D002417:Cattle; D000068016:Eubacteriales / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D003433:Crosses, Genetic; D004032:Diet / Q000662:veterinary*; D004063:Digestion; D007887:Fabaceae / Q000737:chemistry*; D045848:Fibrobacter / Q000145:classification / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D005766:Gastrointestinal Contents / Q000382:microbiology*; D000069196:Gastrointestinal Microbiome; D008297:Male; D050296:Microbial Viability; D058889:Molecular Typing / Q000662:veterinary; D008970:Molecular Weight; D018515:Plant Leaves / Q000737:chemistry; D018520:Plant Shoots / Q000737:chemistry; D018720:Prevotella / Q000145:classification / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D044945:Proanthocyanidins / Q000008:administration & dosage* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012417:Rumen / Q000382:microbiology*; D045857:Ruminococcus / Q000145:classification / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D013045:Species Specificity
chemical_list: D044945:Proanthocyanidins
keywords: Illumina MiSeq; Leucaena; condensed tannin; diversity; molecular weight; rumen bacteria