Landfill leachate shows negative impacts to environment. Designed as a conventional treatment it may not, however, be able to reduce pollutant load to acceptable levels according to legislation and environmental laws. Therefore, complementary post-treatment is often necessary for that matter, where they cooperate with conventional one. For the present work, a rhizospheric bacterium was isolated from Alternanthera philoxeroides (Mart.) Griseb., aquatic macrophyte commonly used in wetland leachate treatment. The bacterium was isolated from rhizosphere and identified through deoxyribonucleic acid sequencing and assessed for its leachate degradation potential. Obtained biomass through bench bioreactor was freeze-dried for preserving its catalytic activity. The results suggest that the isolated bacterium is tolerant in leachate added media, where it presented biomass growth of 1.1 g L−1 after fermentation. When under enriched mineral media conditions, biomass growth was higher (3.9 g L−1), as expected. Once proved to be tolerant and able to grow on a media with high pollutant load (leachate), the isolated bacterium can be exploited for enhancing present landfill leachate post-treatment.