ORIGINAL RESEARCH
Utilization and Characterization of Microbes
for Heavy Metal Remediation
More details
Hide details
1
College of Engineering, Agriculture Aviation Innovation Lab, South China Agriculture University, Guangzhou, China
2
Ministry of Agriculture, Extension Wing, Govt of Khyber Pakhtunkhwa, Pakistan
3
Department of Agronomy, The University of Agriculture, Peshawar, Pakistan
4
Department of Soil and Environmental Sciences, The University of Agriculture, Peshawar, Pakistan
5
Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
6
Department of Life Sciences, Yeungnam University, Gyeongsan 38541, Republic of Korea
Submission date: 2024-02-20
Final revision date: 2024-03-21
Acceptance date: 2024-04-08
Online publication date: 2024-08-05
Corresponding author
Wajid Zaman
Department of Life Sciences, Yeungnam University, Gyeongsan 38541, South Korea
KEYWORDS
TOPICS
ABSTRACT
Heavy metals in forest soils have substantial ecological implications, affecting the soil and the
surrounding ecosystem. These naturally occurring elements, with high atomic weights, become toxic at
elevated concentrations. Notable heavy metals in forest soils include lead, cadmium, mercury, and arsenic.
The profound toxicity of heavy metal pollution poses a significant risk to modern agriculture, with the
potential for accumulation in crops and soils, threatening food security. A crucial aspect of addressing this
challenge involves promptly restoring disrupted agricultural land. This study contributes to agricultural
soil restoration by employing a combination of microorganisms, which have proven effective in alleviating
heavy metal pollution. When paired with Sunflower (Helianthus annus), the combination ensures soil
restoration and enhances food security. The study investigated microorganisms from contaminated soil,
revealing Gram-negative bacilli and cocci arrangements. The colony characteristics, including hues and
diameters, were assessed, with notable findings in samples 1, 2, and 5. The microbial ability to remove
heavy metals (Pb, As, Hg, Ni, and Cd) was quantified, highlighting the diverse capacities among isolates.
Selected isolates (1, 3, 6, 7, and 10) exhibited 25% higher biomass accumulation than the control, extracting
at least 40 mg/L of each metal. Bacterial identification using a Vitek 2 Compact analyzer revealed
Pantoea sp., Achromobacter denitrificans, Klebsiella oxytoca, Rhizobium radiobacter, and Pseudomonas
fluorescens. Biocompatibility testing led to the formation of consortia for soil remediation, with Coalition D
(Achromobacter denitrificans, Klebsiella oxytoca, and Rhizobium radiobacter in a 1:1:2 ratio) confirming
the effective removal of Ni and Pb. Various consortia showed differing performances in removing
composite contaminants, with Coalition D being promising, indicating a potential for phytoremediation.
Optimal cultivation conditions were identified, with Coalition D excelling at metal removal and biomass
accumulation. The temperature, pH, and soil conditions were crucial for Coalition D efficiency, and
combining them with phytoremediation techniques showed promise. Laboratory experiments with
sunflower seedlings confirmed the efficacy of Coalition D in enhancing soil phytoremediation, improving
plant survival, and removing mixed heavy metals.