Journal of Chemical Technology and Biotechnology, Vol.94, No.8, 2452-2464, 2019
Development of novel processes for the aqueous extraction of natural rubber from Taraxacum kok-saghyz (TK)
BACKGROUND Taraxacum kok-saghyz (TK) is a rubber-producing plant being developed as a commercial alternative source of natural rubber (NR). The objective of this study was to investigate processes to extract high quality NR at high yield and purity from TK. Rubber is formed in the roots of TK and exists in mostly solid form. Previously used mechanical processes extract NR from TK roots at low purity (< 90%) that does not meet industry standards (>= 99.8%). To improve this, the effects of root chopping, enzymatic hydrolysis, pebble milling and alkaline pretreatment and purification on NR yield, purity and quality were investigated. RESULTS Enzymatic digestion (with and without alkaline pretreatment), yielded rubber at the highest yield (similar to 80%) and purity (99.4%). Alkaline pretreatment of roots improved NR yield and did not adversely affect quality. More rubber was extractable from chopped roots than whole roots, but the rubber was less pure. Alkaline purification of the extracted crude rubber further increased rubber purity but reduced rubber molecular weight. CONCLUSION Enzymatic digestion with or without alkaline pretreatment forms the basis of aqueous processes that could be used for large-scale, efficient extraction of TK rubber at high yield, purity and quality to meet industry standards for NR. (c) 2019 Society of Chemical Industry
Keywords:Taraxacum kok-saghyz;natural rubber;wet milling;alkaline pretreatment;enzymatic digestion;rubber alkaline purification;extraction process