Lamba Jyoti, Anand Shalini, Dutta Jayanti, Rai Pramod Kumar
Department of Environment Studies, Panjab University, Chandigarh, 160 014, India.
Centre for Fire, Explosive and Environment Safety (CFEES), Defence Research Development Organization (DRDO), Timarpur, Delhi, 110054, India.
Arch Microbiol. 2022 Jul 1;204(7):447. doi: 10.1007/s00203-022-03057-8.
2,4,6-trinitrotoluene (TNT), a nitro-aromatic explosive commonly used for defense and several non-violent applications is contributing to serious environmental pollution problems including human health. The current study investigated the remediation potential of a native soil isolate, i.e., Indiicoccus explosivorum (strain S5-TSA-19) isolated from collected samples of an explosive manufacturing site, against TNT. The survivability of I. explosivorum against explosives is indirectly justified through its isolation; thus, it is being chosen for further study. At a TNT concentration of 120 mg/L within an optimized environment (i.e., at 30 °C and 120 rpm), the isolate was continually incubated for 30 days in a minimal salt medium (MSM). The proliferation of the isolate and the concentration of TNT, nitrate, nitrite, and ammonium ion were evaluated at a particular time during the experiment. Within 168 h (i.e., 7 days) of incubation, I. explosivorum co-metabolically degraded 100% TNT. The biodegradation procedure succeeded the first-order kinetics mechanism. Formations of additional metabolites like 2,4-dinitrotoluene (DNT), 2,4-diamino-6-nitrotoluene (2-DANT), and 2-amino-4,6-dinitrotoluene (2-ADNT), were also witnessed. TNT seems to be non-toxic for the isolate, as it reproduced admirably in TNT presence. To date, it is the first report of Indiicoccus explosivorum, efficiently bio-remediating TNT, i.e., a nitro-aromatic compound via different degradation pathways, leading to the production of simpler as well as less harmful end products. Further, at the field-scale application, Indiicoccus explosivorum may be explored for the bioremediation of TNT (i.e., a nitro-aromatic compound)-contaminated effluents.
2,4,6-三硝基甲苯(TNT)是一种常用于国防及多种非暴力用途的硝基芳香族炸药,它正导致包括人类健康问题在内的严重环境污染问题。当前研究调查了一种从炸药生产场地采集样本中分离出的本地土壤菌株——爆炸嗜印度球菌(菌株S5-TSA-19)对TNT的修复潜力。爆炸嗜印度球菌在炸药环境中的生存能力通过其被分离出来这一事实间接得到证明;因此,它被选作进一步研究对象。在优化环境(即30℃和120转/分钟)下,TNT浓度为120毫克/升时,该菌株在基本盐培养基(MSM)中持续培养30天。在实验的特定时间评估该菌株的增殖情况以及TNT、硝酸盐、亚硝酸盐和铵离子的浓度。在培养168小时(即7天)内,爆炸嗜印度球菌共代谢降解了100%的TNT。生物降解过程符合一级动力学机制。还观察到了2,4-二硝基甲苯(DNT)、2,4-二氨基-6-硝基甲苯(2-DANT)和2-氨基-4,6-二硝基甲苯(2-ADNT)等其他代谢产物的形成。TNT对该菌株似乎无毒,因为它在有TNT存在的情况下能良好繁殖。迄今为止,这是关于爆炸嗜印度球菌通过不同降解途径有效生物修复TNT(一种硝基芳香族化合物),从而产生更简单且危害更小的终产物的首次报道。此外,在实地应用中,可以探索利用爆炸嗜印度球菌对受TNT(一种硝基芳香族化合物)污染的废水进行生物修复。