strain NBN2, Bacillus cereus strain AGP-03, Bacillus cytotoxicus NVH 391–98 and
Bacillus sp. L10 isolated from saline soil samples. At 200 mg L
À1 concentration, the
consortium decolorized 97 and 95% of Direct Blue 151 and Direct Red 31 dyes,
respectively, within 5 days at pH 9.5 (Lalnunhlimi and Krishnaswamy 2016).
Overall, bacterial treatment has gained momentum as an efficient technique for
dye degradation and decolorization. However, further developments are required to
cope with some challenges such as toxicity of the treated effluents and scale-up
applications of bacterial techniques in real industrial sewage and drains. The solution
to the mentioned challenges lies in advanced knowledge of fundamental biological
sciences coupled with the revolutionary analytical techniques based on genomics
and proteomics.
17.4.2 Dye Removal via Algae Strains
Biosorption of malachite green oxalate dye was attempted using Caulerpa racemosa
var. cylindracea. The system suggested an alternative to recently reported
cyclodextrin-based adsorbent for 2 because of the lower equilibrium time and high
adsorption capacity (Bekçi et al. 2009). In another study, Chlorella vulgaris
UMACC 001 was used to remove Supranol Red 3BW and textile wastewater
using high-rate algal ponds. Decolorization reached up to 41–50% and chemical
oxygen demand removal 38–62%, and biomass was found to be 0.17–2.26 mg
chlorophyll a/L. Additional benefits of high-rate algal ponds were proposed in the
form of a polishing system for textile wastewater prior to the disposal and use of
algal biomass as feedstock for biofuel generation (Lim et al. 2010). 1 was adsorbed
using raw and dried Mediterranean green alga Enteromorpha spp. (Ncibi et al.
2009). Some reports suggested chemical and surface modifications in algae to
enhance sorption capacity, for instance, removal of lipid fraction from Sargassum
muticum biomass increased the sorption efficiency (Rubín et al. 2010). Likewise,
marine alga Ulva lactuca and Systoceira stricta modified with activated carbon
showed significantly improved adsorption capacities for 2 (400 mg g
À1 ) and Safranin O (526 mg g
À1 ) (Salima et al. 2013).
Reactive Red 120 dye was removed by adsorption using Spirulina platensis
microalgae as sorbent. Microalgae successfully removed nearly 97% of dye, thus
indicating the suitability of SP for bioremediation of simulated dyestuff effluents
(Cardoso et al. 2012). Biosorption of Acid Black 1 was carried out using brown
marine macroalga, Nizamuddin zanardini, which utilized hydroxyl and amine surface functional groups for biosorption (Esmaeli et al. 2013). Textile dyes 4, basic red
46, and basic blue 3 taken from polluted water were subjected to biosorption using
filamentous green alga Spirogyra sp. Equilibrium was achieved in 1 h and
biosorption of dyes in 72 h was highest for basic red 46, the average for basic blue
3, and lowest for 4 (Khataee et al. 2013).
Immobilization of microalgae has been suggested to cope with a low resistance to
temperature and chemicals. A study used 1% к-carrageenan and 2% sodium alginate
638
R. S. Ashraf et al.
Bacillus sp. L10 isolated from saline soil samples. At 200 mg L
À1 concentration, the
consortium decolorized 97 and 95% of Direct Blue 151 and Direct Red 31 dyes,
respectively, within 5 days at pH 9.5 (Lalnunhlimi and Krishnaswamy 2016).
Overall, bacterial treatment has gained momentum as an efficient technique for
dye degradation and decolorization. However, further developments are required to
cope with some challenges such as toxicity of the treated effluents and scale-up
applications of bacterial techniques in real industrial sewage and drains. The solution
to the mentioned challenges lies in advanced knowledge of fundamental biological
sciences coupled with the revolutionary analytical techniques based on genomics
and proteomics.
17.4.2 Dye Removal via Algae Strains
Biosorption of malachite green oxalate dye was attempted using Caulerpa racemosa
var. cylindracea. The system suggested an alternative to recently reported
cyclodextrin-based adsorbent for 2 because of the lower equilibrium time and high
adsorption capacity (Bekçi et al. 2009). In another study, Chlorella vulgaris
UMACC 001 was used to remove Supranol Red 3BW and textile wastewater
using high-rate algal ponds. Decolorization reached up to 41–50% and chemical
oxygen demand removal 38–62%, and biomass was found to be 0.17–2.26 mg
chlorophyll a/L. Additional benefits of high-rate algal ponds were proposed in the
form of a polishing system for textile wastewater prior to the disposal and use of
algal biomass as feedstock for biofuel generation (Lim et al. 2010). 1 was adsorbed
using raw and dried Mediterranean green alga Enteromorpha spp. (Ncibi et al.
2009). Some reports suggested chemical and surface modifications in algae to
enhance sorption capacity, for instance, removal of lipid fraction from Sargassum
muticum biomass increased the sorption efficiency (Rubín et al. 2010). Likewise,
marine alga Ulva lactuca and Systoceira stricta modified with activated carbon
showed significantly improved adsorption capacities for 2 (400 mg g
À1 ) and Safranin O (526 mg g
À1 ) (Salima et al. 2013).
Reactive Red 120 dye was removed by adsorption using Spirulina platensis
microalgae as sorbent. Microalgae successfully removed nearly 97% of dye, thus
indicating the suitability of SP for bioremediation of simulated dyestuff effluents
(Cardoso et al. 2012). Biosorption of Acid Black 1 was carried out using brown
marine macroalga, Nizamuddin zanardini, which utilized hydroxyl and amine surface functional groups for biosorption (Esmaeli et al. 2013). Textile dyes 4, basic red
46, and basic blue 3 taken from polluted water were subjected to biosorption using
filamentous green alga Spirogyra sp. Equilibrium was achieved in 1 h and
biosorption of dyes in 72 h was highest for basic red 46, the average for basic blue
3, and lowest for 4 (Khataee et al. 2013).
Immobilization of microalgae has been suggested to cope with a low resistance to
temperature and chemicals. A study used 1% к-carrageenan and 2% sodium alginate
638
R. S. Ashraf et al.