Distribution of the non-isoprene components in the four Hevea brasiliensis latex centrifugation fractions

This work is part of a larger project aiming at elucidating the mechanisms by which the biochemical components naturally occurring in Hevea brasiliensis latex influence the structuration of natural rubber (NR). To achieve this overall objective, our strategy consists of measuring the physical properties of NR samples made of reconstructed lattices which were obtained by mixing different proportions of C-serum and bottom fraction (lutoids) to rubber fraction made of small and large particles. This work represents the first step of the above-mentioned project where we carried out a systematic study to identify and locate the main biochemical components of latex that might drive NR structuration. Fresh latex from RRIM600 and PB235 clones was fractionated by centrifugation into 4 fractions: large rubber particles, small rubber particles, C-serum and bottom fraction (lutoids + Frey-Wyssling particles). The fractions were further analyzed to provide a comprehensive description of their biochemical composition (lipids, proteins, minerals) in comparison with the original whole latex. The results gathered in this work are essential for further study of the quantitative influence of each component on NR structuration and properties.