Liquid-phase oxidation of betulin extracted from birch bark was studied over gold catalysts supported on a range of supports (hydrotalcite, ZrO₂, ZnO, MgO, CeO₂, La₂O₃, HMS and various alumina) with different morphology and properties. Gold catalysts as well as the corresponding supports were characterized by XRD, BET, ICP-OES, XPS and TEM. It was found that the nature of the support plays a decisive role in betulin oxidation over gold-based catalysts, expressed in the influence on the average size and distribution of gold nanoparticles and, thereby, on their catalytic performance (activity and selectivity) in betulin oxidation. Moreover, it was revealed that betulin oxidation catalyzed by gold is a structure sensitive reaction, requiring an optimal size of gold nanoparticles of ca. 3.3 nm. The most suitable support for gold was found to be alumina. Kinetic studies allowed determination of reaction orders and conditions favorable for selective formation of a particular oxo-derivative of betulin (betulone, betulinic and betulonic aldehydes, betulinic acid).

在载有一系列载体（水滑石，ZrO ₂，ZnO，MgO，CeO ₂，La ₂ O ₃，HMS和各种氧化铝）具有不同的形态和性能。通过XRD，BET，ICP-OES，XPS和TEM对金催化剂以及相应的载体进行了表征。已发现，载体的性质在桦木蛋白氧化中比金基催化剂起决定性作用，表现为对金纳米颗粒的平均尺寸和分布的影响，从而对其在桦木蛋白中的催化性能（活性和选择性）产生影响。氧化。此外，已经发现，由金催化的桦木素氧化是结构敏感的反应，需要最佳尺寸的金纳米粒子约。3.3纳米 发现最适合金的载体是氧化铝。动力学研究可以确定有利于选择性合成甜菜碱（贝他隆，