General Aspects/Case Studies on Sources and Bioremediation Mechanisms of Metal(loid)s 157

Table 9.2. Remediation of metal(loid)s by the combination of plants and microbial species.

Metals

Plant species

Microbial Species

Mechanism of removal

References

Zn

Brassica juncea

Pseudomonas

brassicacerarum,

Rhizobium leguminosarum

Organic acid secretion and

metal chelation enhancement by

phytochelatins

Adediran et al.

2015

Cicuta virosa

Rhodopseudomonas sp.,

Pseudomonas putida

Siderophores and indole-3­

acetic acid production

Nagata et al. 2015

Ni

Alyssum

pintodasilvae

Arthrobacter

nicotinovorans

Siderophores and organic acid

production

Cabello-Conejo

et al. 2014

Helianthus

annuus

Pseudomonas libanensis

and Claroideoglomus

claroideum

Solubilization of phosphate,

ni phytostabilized by

exopolysaccharide (EPS)

Ma et al. 2019

Al

Miscanthus

sinensis

Chaetomium cupreum

Production of siderophore

(oosporein)

Haruma et al.

2019

Cd

Ocimum

ratissimum

Arthrobacter sp.

Production of EPS

Prapagdee and

Khonsue 2015

Zn, Cu and Pb

Clethra

barbinervis

Clethra barbinervis,

Rhizodermea veluwensis

Melanin and siderophore

production

Yamaji et al. 2016

Zn, Cd and Pb

Sedum

plumbizincicolaa

Endophytic bacterium E6S

Organic acid production,

Aminocyclopropane-1­

carboxylate (ACC) and Indole­

3-acetic acid (IAA) production,

phosphate solubilization,

Ma et al. 2016

As, Cd, Cu, Pb

and Zn

Miscanthus

sinensis

Pseudomonas koreensis

AGB-1

Aminocyclopropane-1­

carboxylate (ACC) deaminase

Babu et al. 2015

Cr(VI), Fe,

Mn, Zn, Cd,

Cu and Ni

Vetiveria

zizanioides

Bacillus cereus

Production of IAA, ACC,

solubilize phosphate and

production of ACC

Nayak et al. 2018

Cd and Pb

Simplicillium

chinense

Phragmites communis

Pb bio sorption by EPS and Cd

chelate formation

Jin et al. 2019

Cd, Zn and Cu

Solanum nigrum

Pseudomonas sp. Lk9

Organic acids and siderophore

and biosurfactant production

Chen et al. 2014

Zn, Cd and Pb

Salix dasyclados

Streptomyces sp.

Siderophore production

Złoch et al. 2017

9.6 Case Studies on Bioremediation of Metal(oids)

9.6.1 Arsenic

Microorganisms have evolved arsenic defense systems because of arsenic’s ubiquitous presence in

the environment. The arsenic resilience operon’s existence (ars) encodes enzymes degradation of

arsenate in an exhaustive study undertaken in Leon, Spain (Mateos et al. 2006). It was noted that as

arsenate gains entry into the cell via specialized (Pst) or nonspecific (Pit) phosphate transporters, its

incorporation in phosphate-rich fluids or environments is lower. When C. glutamicum is cultivated

in a low-phosphate medium or when the concentration of phosphate is reduced by precipitation,

As(V) absorption increases, followed by disabling the three arsenite permease genes found in

C. glutamicum’s genome, arsenite outflow was minimized. C. glutamicum ArsB1-B2, a double

arsenite permease mutant, was particularly sensitive to arsenate and arsenite (Ordóñez et al. 2005).

Ordóñez et al. (2005) successfully created C. glutamicum strains using omics approaches that may

horde heavy metals outside the cell (as a biosorbent), similar to E. coli and Ralstonia eutropha

(Kotrba et al. 1999) and Ralstonia eutropha (Valls et al. 2000).