Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 5/15/2007
Publication Date: 9/23/2007
Citation: Martins, M.A., Mcmahan, C.M., Goncaves, P.S., Mattoso, L.H. 2007. Elemental Analysis and Protein Quantification of Raw Natural Rubber of IAC Series 400 Clones. Proceedings of the 11th International Seminar on Elastomers.
Interpretive Summary: The USDA’s Domestic Natural Rubber project has studied the biochemistry of rubber biosynthesis in divergent species, with a focus on natural rubber from Parthenium argentatum, guayule, a woody desert shrub suitable for cultivation in some parts of the United States. The reported studies of the chemistry of rubber biosynthesis, reported here and elsewhere, have typically explored interspecies comparisons in order to elucidate biosynthetic mechanisms. Our collaboration provides the opportunity to study within-a-species clonal variations from both a technological and biochemical perspective. A greater understanding rubber biosynthesis and its regulation will allow production of greater yields of higher molecular weight rubber molecules, whether applied to breeding programs, metabolic engineering, or possibly agronomic practices. Moreover, lessons learned from the study of H. braziliensis will greatly contribute to development of P. argentatum and other rubber-producing species. The collaboration with Embrapa Instrumentação Agropecuária Sao Carlos, Brasil, is part of the ARS/Embrapa LABEX program.
Technical Abstract: Protein, nitrogen and sulfur contents were investigated for natural rubber from commercial Hevea, synthetic polyisoprene, and new IAC clones from Mococa city (IAC 405, 406, 410, 413, and 420), Jaú city (IAC 400, 401, 402, and 417), and from RRIM 600 clone (used as a control in both cases). IAC 405 and RRIM 600 clones showed, respectively, the highest nitrogen and protein contents among the clones from Mococa, and similar sulfur results. A different trend was observed for Jáu, where RRIM 600 and IAC 400 clones showed the highest nitrogen and sulfur contents, respectively, showing that not only the clone type but also the region of plantation plays an important role on determining the rubber composition.