The enzymatic degradation of the rubber polymer poly(cis-1,4-isoprene), e.g. by the latex clearing protein Lcp1_VH2 of Gordonia polyisoprenivorans VH2 has been demonstrated with latex milk or pure isoprene-rubber particles, recently. Unfortunately, carbon black filled vulcanized rubber (CFVR) making the biggest part of worldwide rubber wastes, contains several harmful additives making microbial and enzymatic rubber degradation challenging. However, this study demonstrates the successful enzymatic cleavage of industrially produced CFVR. The formation of the cleavage products, oligo(cis-1,4-isoprenoids), from incubating CFVR particles with Lcp1_VH2 was detected by HPLC–MS. Various organic solvents were tested to remove harmful or inhibiting additives like antioxidants to enhance product formation. The pretreatment of CFVR particles, especially with chloroform or cyclohexane, significantly improved the degradation. It was also demonstrated that reducing the particles size and thus increasing the enzymatically accessible surface area of the particles led to a strong acceleration of the degradation process. Furthermore, ATR-IR analyses showed that Lcp1_VH2 led to the functionalization of the rubber particle surface with carbonyl groups by cleaving isoprene chains, still linked to the particle. Both, the oligo(cis-1,4-isoprenoids) as well as the functionalized rubber particles, are potentially important products, which can be reused as fine chemicals or as additives in rubber production. The present study, showing the enzymatic degradation of common CFVR for the first time, takes an important step towards a new way of rubber waste disposal and indicates the economic feasibility of an efficient and environmentally friendly recycling process by using the rubber oxygenase Lcp1_VH2.

最近，已证明用乳胶乳或纯异戊二烯橡胶颗粒对橡胶聚合物聚顺式（1，4-异戊二烯）的酶降解，例如通过Gordonia聚异戊二烯醛_VH2的乳胶清除蛋白Lcp1 _VH2进行的酶降解。不幸的是，炭黑填充的硫化橡胶（CFVR）是全球橡胶废料的最大组成部分，其中包含多种有害添加剂，使微生物和酶促橡胶的降解面临挑战。但是，这项研究证明了工业生产的CFVR的成功酶解。通过将CFVR颗粒与Lcp1 _VH2一起孵育形成裂解产物寡核苷酸（顺式-1,4-异戊二烯）通过HPLC-MS检测。测试了各种有机溶剂以去除有害或抑制性添加剂，例如抗氧化剂，以增强产品形成。CFVR颗粒的预处理，特别是用氯仿或环己烷的预处理，显着改善了降解。还证明减小颗粒尺寸并因此增加颗粒的酶促可及的表面积导致降解过程的强烈加速。此外，ATR-IR分析表明，Lcp1 _VH2通过裂解仍与橡胶颗粒相连的异戊二烯链，使带有羰基的橡胶颗粒表面官能化。这两个，寡（顺-1,4-异戊二烯酸酯）以及功能化的橡胶颗粒是潜在的重要产品，可以用作精细化学品或在橡胶生产中用作添加剂。本研究首次展示了普通CFVR的酶降解作用，朝着橡胶废料处理的新方法迈出了重要的一步，并表明了通过使用橡胶加氧酶Lcp1 _VH2进行高效，环保的回收过程的经济可行性。