UPM Institutional Repository

Polymerization degrees, molecular weights and protein-binding affinities of condensed tannin fractions from a Leucaena leucocephala hybrid


Citation

Saminathan, Mookiah and Tan, Hui Yin and Sieo, Chin Chin and Abdullah, Norhani and Wong, Clemente Michael Vui Ling and Abdul Malek, Emilia and Ho, Yin Wan (2014) Polymerization degrees, molecular weights and protein-binding affinities of condensed tannin fractions from a Leucaena leucocephala hybrid. Molecules, 19 (6). pp. 7990-8010. ISSN 1420-3049

Abstract

Condensed tannins (CTs) form insoluble complexes with proteins and are able to protect them from degradation, which could lead to rumen bypass proteins. Depending on their degrees of polymerization (DP) and molecular weights, CT fractions vary in their capability to bind proteins. In this study, purified condensed tannins (CTs) from a Leucaena leucocephala hybrid were fractionated into five different molecular weight fractions. The structures of the CT fractions were investigated using 13C-NMR. The DP of the CT fractions were determined using a modified vanillin assay and their molecular weights were determined using Q-TOF LC-MS. The protein-binding affinities of the respective CT fractions were determined using a protein precipitation assay. The DP of the five CT fractions (fractions F1–F5) measured by the vanillin assay in acetic acid ranged from 4.86 to 1.56. The 13C-NMR results showed that the CT fractions possessed monomer unit structural heterogeneity. The number-average molecular weights (Mn) of the different fractions were 1265.8, 1028.6, 652.2, 562.2, and 469.6 for fractions F1, F2, F3, F4, and F5, respectively. The b values representing the CT quantities needed to bind half of the maximum precipitable bovine serum albumin increased with decreasing molecular weight—from fraction F1 to fraction F5 with values of 0.216, 0.295, 0.359, 0.425, and 0.460, respectively. This indicated that higher molecular weight fractions of CTs from L. leucocephala have higher protein-binding affinities than those with lower molecular weights.


Download File

[img] PDF
Polymerization Degrees, Molecular Weights and.pdf
Restricted to Repository staff only

Download (1MB)

Additional Metadata

Item Type: Article
Divisions: Faculty of Biotechnology and Biomolecular Sciences
Institute of Bioscience
Institute of Tropical Agriculture
DOI Number: https://doi.org/10.3390/molecules19067990
Publisher: MDPI
Keywords: Condensed tannins; NMR; Degree of polymerization; Q-TOF LC-MS; Molecular weight; Protein-binding affinity; Leucaena leucocephala
Depositing User: Nurul Ainie Mokhtar
Date Deposited: 24 Dec 2015 05:56
Last Modified: 24 Dec 2015 05:56
Altmetrics: http://www.altmetric.com/details.php?domain=psasir.upm.edu.my&doi=10.3390/molecules19067990
URI: http://psasir.upm.edu.my/id/eprint/34956
Statistic Details: View Download Statistic

Actions (login required)

View Item View Item