School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand.
Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand.
Plant Physiol Biochem. 2018 Sep;130:181-191. doi: 10.1016/j.plaphy.2018.06.042. Epub 2018 Jul 4.
This study was performed to determine the effect of plant-endophytic Enterobacter sp. EN2 interactions and blue-red LED light conditions on gaseous benzene removal by plants. It was found that under consecutive benzene fumigation for three cycles (18 days), inoculation of the strain EN2 into sterilized and non-sterilized native C. comosum resulted in significantly increased gaseous benzene removal compared to that in non-inoculated groups under the same light conditions (P < 0.05). Remarkably, EN2 colonization in inoculated plants under LED conditions was higher than under fluorescence conditions as the EN2 could grow better under LED conditions. Strain EN2 possesses NADPH that is used to facilitate benzene degradation and modulate plant growth under benzene stress by bacterial IAA production and ACC deaminase activity; higher IAA and lower ethylene levels were found in inoculated plants compared to non-inoculated ones. These contributed to better benzene removal efficiency. Interestingly, under fumigation for 16 cycles (67 days), there was no difference in gaseous benzene removal between inoculated plants and non-inoculated plants under the same light conditions at initial benzene concentrations of 5 ppm. This is probably due to EN2 reaching maximum growth under all treatments. However, C. comosum exhibited better benzene removal under LED conditions than under fluorescence conditions during 16 cycles, possibly due to better photosynthetic performance and plant growth, leading to more NADPH, and eventually enhanced benzene removal efficiency. Hence, the most efficient acceleration of benzene removal was provided by inoculation of strain EN2 onto C. comosum under blue-red LED light conditions.
本研究旨在确定植物内生肠杆菌 EN2 与红蓝 LED 光条件相互作用对植物去除气态苯的影响。结果发现，在连续三次（18 天）苯熏气处理下，与相同光照条件下未接种的对照组相比，该菌株 EN2 接种到灭菌和未灭菌的本地长春蔓中，可显著提高气态苯的去除率（P<0.05）。值得注意的是，与荧光条件相比，EN2 在接种植物中的定植率在 LED 条件下更高，因为 EN2 在 LED 条件下生长得更好。该菌株 EN2 具有 NADPH，可通过细菌 IAA 产生和 ACC 脱氨酶活性促进苯降解和调节植物在苯胁迫下的生长；与未接种的植物相比，接种植物中的 IAA 更高，乙烯水平更低。这有助于提高苯的去除效率。有趣的是，在 16 次（67 天）熏气处理下，在初始苯浓度为 5 ppm 的相同光照条件下，接种植物和未接种植物之间的气态苯去除率没有差异。这可能是由于 EN2 在所有处理下都达到了最大生长。然而，在 16 次循环中，长春蔓在 LED 条件下的苯去除效率优于荧光条件，这可能是由于更好的光合作用性能和植物生长，导致更多的 NADPH，最终提高了苯的去除效率。因此，在蓝-红 LED 光条件下，将菌株 EN2 接种到长春蔓上可最有效地加速苯的去除。
