12.5 Biosorption Potential of Microbes and Agri-Food Waste

179

obtainable substitute biosorbent for the exclusion of cationic dyes from the polluted

water [15]. Waste obtained from Artocarpus odoratissimus fruit acts as a biosorbent

for the removal of Cu²⁺ and Cd²⁺ ions. It is possible because of the presence of

organic functionalities such as alcoholic, carbonyl, phenolic, amido, amino, and sul-

fydryl moieties, which have a greater affinity for such metals to induce metal chela-

tion or metal complexes [24]. Cynara scolymus agro-waste biomass as a biosorbent

is recognized as an alternate to contribute to the elevation of the circular economy,

because of its cost-effectiveness, no harmful impact on the ecosystem, and its abil-

ity to remove metal ions such as Pb²⁺, Cd²⁺, and Cu²⁺ [11]. Cotton stalks, maize

stalks, and rice straw removed heavy metals significantly in which maximum exclu-

sion ability is of cotton stalks due to the presence of cellulose, hemicellulose, and

lignin in higher amounts in comparison to other crop-residues [24].

12.5

Biosorption Potential of Microbes and Agri-Food

Waste

Use of microbes as biosorbents provides a promising strategy and can be advan-

tageous because of their inexpensiveness, capability to regenerate, enhanced

pollutants exclusion, and efficient retrieval of some worthwhile metals [12]

(Figure 12.1). Utilization of microbial biomass for the removal of noxious metals

from polluted areas has become a noteworthy [13]. Microbial cells of Pseudomonas

putida I3, Microbacterium sp. OLJ1, and the fungus Talaromyces amestolkiae

significantly removed Pb²⁺, and these biosorbents recognized to have greater

adsorption ability and mechanical durability due to the variations in cell walls and

cellular organization [14]. Phosphorylated dry baker’s yeast cells showed a greater

biosorption capacity for the removal of Cd²⁺, Cu²⁺, Pb²⁺, and Zn²⁺ in comparison to

non-phosphorylated dry baker’s yeast because of the great negative charges added

through the phosphorylation mechanism [12]. In the present day time, utilization

of algae as sustainable biosorbents has gained huge consideration among scientists

[13]. Algae are recognized as a good biosorbent due to the existence of exceptional

chemical constituents, large surface area, greater binding affinity, and high uptake

efficiency [25]. Penicillium chrysogenum biomass showed higher biosorption of

100.41 mg/g dry biomass for Cd²⁺ metal ions according to the Langmuir isotherm;

in addition to this, Fourier-transform infrared spectroscopy (FTIR), scanning

electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) analysis

exhibited that the –OH and –C=O groups on the fungus cell wall are the major

binding positions for Cd²⁺ [26]. Trametes sp. SC-10 fungus showed maximum

biosorption ability of 221.6 mg/g for Acid blue 161 (AB-161) dye; therefore, it is

well-thought-out as a promising biosorbent to decontaminate industrial wastes [27].

Garlic waste exhibited greater removal of malachite green, i.e. 232.56 mg/g via the

Langmuir model at pH 8.0 and 298 K temperature, and hence, garlic root waste can

be utilized as a cost-effective biosorbent to eliminate dyes from industrial wastew-

ater [28]. Bagasse fly ash (BFA) significantly removed 2,4-D. Hence, BFA can be

used as a cost-effective and effective biosorbent. Stem and leaves powder of potato