Centre for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; Beijing Energy Conservation & Sustainable Urban and Rural Development Provincial and Ministry Co-construction Collaboration Innovation Center, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
Centre for Urban Environmental Remediation, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; Beijing Energy Conservation & Sustainable Urban and Rural Development Provincial and Ministry Co-construction Collaboration Innovation Center, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; The College of Forestry, Beijing Forestry University, Beijing, 100083, China.
Environ Res. 2024 Nov 15;261:119716. doi: 10.1016/j.envres.2024.119716. Epub 2024 Aug 2.
Bentonite is a non-metallic mineral with montmorillonite as the main component. It is an environmentally friendly mineral material with large reserves, wide distribution, and low price. Bentonite can be easily modified organically using the surfactant saponin to obtain saponin-modified bentonite (Sap-BT). This study investigates the immobilization of crude enzymes obtained from Trametes versicolor by physical adsorption with Sap-BT. Thus, saponin-modified bentonite immobilized crude enzymes (CE-Sap-BT) were developed to remove benzo[a]pyrene. Immobilization improves the stability of free enzymes. CE-Sap-BT can maintain more than 80% of activity at 45 °C and after storage for 15 d. Additionally, CE-Sap-BT exhibited a high removal rate of benzo[a]pyrene in soil, with 65.69% after 7 d in highly contaminated allotment soil and 52.90% after 6 d in actual soil contaminated with a low concentration of benzo[a]pyrene at a very low laccase dosage (0.1 U/3 g soil). The high catalytic and removal performance of CE-Sap-BT in contaminated sites showed more excellent practical application value.
膨润土是以蒙脱石为主要成分的非金属矿产，是一种储量大、分布广、价格低廉的环保型矿物材料。膨润土可通过表面活性剂皂素进行有机改性，得到皂素改性膨润土（Sap-BT）。本研究采用物理吸附法，用 Sap-BT 固定糙皮侧耳菌提取的粗酶，制备了皂素改性膨润土固定化粗酶（CE-Sap-BT），用于去除苯并[a]芘。固定化提高了游离酶的稳定性，CE-Sap-BT 在 45°C 下保持超过 80%的活性，在储存 15 天后仍能保持 80%以上的活性。此外，CE-Sap-BT 在污染土壤中对苯并[a]芘的去除率很高，在高度污染的分配土地中经过 7 天处理后，去除率达到 65.69%，在实际受低浓度苯并[a]芘污染的土壤中经过 6 天处理后，去除率达到 52.90%，所用漆酶剂量非常低（0.1 U/3 g 土壤）。CE-Sap-BT 在污染场所具有较高的催化和去除性能，显示出更优异的实际应用价值。
