Table 2.3 Biosorption of heavy metals by different fungi.
| Fungal biomass (biosorbent) | Metal ions (biosorbate) | Functional groups | References |
|---|---|---|---|
| Pleurotus ostreatus | Chromium | Carboxyl, amine groups | (Arbanah et al., 2013) |
| Hydrilla verticillata | Cadmium | Carboxyl, hydroxyl, amine groups | (Acosta Rodríguez et al., 2013) |
| Aspergillus terreus | Copper | Carboxyl groups | (Gulati et al., 2002) |
| Trametes versicolor | Nickel | Carboxyl, hydroxyl, amine groups | (Subbaiah and Yun, 2013) |
| Penicillium chrysogenum | Arsenic | Carboxyl, amino groups | (Mamisahebei et al., 2007) |
| Phanerochaete chrysosporium | Lead | Hydroxyl, amino groups | (Haluk Ceribasi and Yetis, 2004) |
| Pencillium simpliccium | Zinc | Carboxyl, amino groups | (Fan et al., 2008) |
| Aspergillus fumigatus | Mercury | Amino, hydroxyl groups | (Mamisahebei et al., 2007) |
Different parameters of metal ions such as valency, diameter, cell age, culture conditions, concentration of metals, temperature, and pH influence the process of biosorption (Wang and Chen, 2006). Biosorption involves amino, carboxyl, and hydroxyl functional groups. The isothermal model of Langmuir was better adapted to a biosorption ion exchange mechanism (Luo et al., 2010). Yeasts’ huge size, on the other hand, makes them potential candidates for metal bioremediation. Table 2.4 lists the many yeast strains utilized in biosorption.
Biosorbents Derived from Plant and Animal Waste
Solid wastes derived from flora and fauna are plentiful, low‐cost, renewable resources. They're made in vast quantities every year, and disposing of them is usually a problem. An important area of research is to find meaningful uses for these materials. They can be used to minimize waste and create cost‐effective products (Kulkarni, 2014).
Plants disposed of as agricultural waste and food industry waste can be used as biosorbents. This is a method of repurposing and recycling discarded materials, so using plant materials has no significant cost (Ali Redha, 2020). Plant‐derived wastes are predominantly made up of cellulose, with structural components such as lignin, proteins, hemicellulose, carbohydrates, lipids, and starch (Rajapaksha et al., 2015). Plant biosorbents can absorb water because of the presence of carboxylic and phenolic functional groups in the cellulosic matrix and components linked with cellulose, such as hemicellulose and lignin (Abdi and Kazemi, 2015). Based on cation exchange between binding sites and metal ions, the metal ions bind with functional groups, resulting in biosorption and, therefore, the removal of the metal ions from media (Abdi and Kazemi, 2015). Table 2.5 lists the various plants employed as biosorbents.
Table 2.4 Biosorption of heavy metals by different yeasts.
| Yeast biomass(biosorbent) | Metal ions(biosorbate) | References |
|---|---|---|
| Candida utilis | Chromium | (Anaemene, 2012) |
| Saccharomyces cerevisiae | Cadmium | (Das et al., 2008) |
| Saccharomyces cerevisiae | Cobalt | (Arakaki et al., 2011) |
| Candida pelliculosa | Copper | (Apinthanapong and Phensaijai, 2009) |
| Mucor rouxii | Lead | (Muraleedharan et al., 1991) |
| Saccharomyces cerevisiae | Mercury | (Anaemene, 2012) |
| Saccharomyces cerevisiae | Nickel | (Siñeriz et al., 2009) |
| Thiobacillusthiooxidans | Zinc | (Nagashetti et al., 2013) |
Table 2.5 Biosorption of heavy metals by different plant materials.
| Plant waste | Metal | Adsorption capacity | Reference |
|---|---|---|---|
| Wheat bran | Mercury | 82% | (Farajzadeh and Monji, 2004) |
| Black gram husk | Lead | 93% | (Saeed et al., 2005) |
| Rice bran | Cadmium | 80% | (Montanher et al., 2005) |
| Baggase | Zinc | 90–95% | (Mohan and Singh, 2002) |
| Activated carbon of peanut shells | Nickel | 75% |
(Wilson et al., 2006)
|