A brief review focuses on significant role and potential of algae in pollutants removal from the waste water.

1. Prepared By:
Rashmi Paliwal

2. Introduction
Immobilized Microalgae
Transgenic Algae
Advantages of Algal Technology
Applications

3. World is facing the problems with a wide variety of
pollutants.
Many methods are available for the removal of these
pollutants but they are not widely acceptable.
Biological methods are often preferred since they have
many advantages like rapid biodegradation rates, low
sludge yield and excellent process stability.

4. Use of macro-algae or micro-algae for the removal or biotransformation
of pollutants, including nutrients and xenobiotics from wastewater and
CO2 from waste air.
Naturally occurring phenomenon
Algae utilize the wastes as nutritional sources and enzymatically degrade
the pollutants.
The xenobiotics and heavy metals are known to be detoxified/
transformed/or volatilized by algal metabolism.
An integrated algae and bacterial based wasted water system can
remove a wide variety of contaminants.

6. Division Algal Species Metal
(Common Name)
Chlorella sp. and Scenedesmus sp. Cu, Cd
Cladophora, Thalassiosira Cu, Zn and Cd
pseudonana and Ditylum birghtwellii
Chlorella vulgaris Zn, Cd
Chlorophyta Scendesmus acutus Cr
(Green algae) Scenedesmus obliquus Co
Scenedesmus subspicatus Al
Scenedesmus quadricauda Zn, Cu and Ni
Sargasuum nutan Au
Phaeophyta Ascophyllum nodosum, Au, Cd, Co, Ni, Pb
(Brown algae) S. Vulgare Cu, Ni, Pb, Cd
Fucus Vesiculosus Pb, Ni, Cu, Cd, Zn
Laminaria japonica Zn, Cu
Rhodophyta Acrosorium uncinatum Cu, Zn, Ni, Pb
(Red algae)
Davis, et.al., (2003)

7. Immobilization:
Transfer of cells from a free state to a state in which
they are confined/localized in a certain defined region
of space.
Advantages:
Reusing the biomass after regeneration.
Avoids filtration of the treated wastewater.
More than one microorganism can be immobilize .

8. Microalgae species Immobilizing Material Pollutant
Chlorella homosphaera Alginate Cd, Au, Zn
C. vulgaris Alginate, k-Carrageenan Cd, Cu, Zn
Polyurethane foam
Silica gel Hg
Chlamydomonas reinhardtii Alginate Cd, Pb, Hg
Oscillatoria sp. Alginate Cd
Scenedesmus acutus Alginate, k-Carrageenan Cd, Cr
Polyurethane foam Zn
Scenedesmus quadricauda Alginate Ni, Zn, Cu
Chlorella regularis Polyacrylamide Uranium
Spirulina platensis Silica gel Cd

9. Contd…
Microalgae species Immobilizing Pollutant
Material
Phormidium laminosum Polysulphone foam Mixture of Cu, Fe, Ni, Zn
and epoxy resin
Chlorella salina Alginate Mn, Zn, Co
Sargassum baccularia Polyvinyl alcohol Cu
Chlorella emersonii; C. vulgaris Alginate Organotin Compounds
(Biocides)
Phaeodactylum tricornutum Alginate linear alkylbenzene
sulphonate (LAS) a
surfactant
Chlorella sp.; Phormidium sp.; Capron fibers Mix of phenols, oil spill
Scenedesmus obliquus; (synthetic) and heavy metals
Stichococcus sp.
Bashan & Bashan, (2010)

10. Transgenesis in algae is a complex but fast growing technique.
Genetic manipulations in algae to improve their detoxification
ability.
Very few species of microalgae have been genetically transformed
with efficiency.
Requirement of Algal Transformation:
Previous molecular, biochemical, physiological or ecological
knowledge of the target species.
Extensive sequence information.

11. Species Utilization
Green algae
Chlamydomonas reinhardtii biomass from transgenics for animal health and feed;
bioremediation,
Ulva spp. environmental monitoring; production of recombinant proteins.
biomass for food and feed; extracts for cosmetics, wastewater
Monostroma spp. Treatment.
biomass for food; wastewater treatment.
Brown algae
Laminaria spp.
alginate for food, pharmaceuticals, and cosmetics; biomass for food
Sargassum spp. and feed; wastewater treatment.
Macrocystis pyrifera Wastewater treatment.
alginate for pharmaceuticals, cosmetics, food, and textile printing;
Lessonia spp. biomass for feed and fuel; wastewater treatment.
alginate for pharmaceuticals, cosmetics, food, and textile printing;
wastewater treatment.
Hallmann, (2007)

14. Cost parameter Conventional Phycoremediation Annual cost benefit
Effluent Treatment
Acidity - caustic soda Algal treatment Rs. 50 lakhs spent
High levels of for caustic soda
dissolved carbon annually is saved
dioxide (100%).
Sludge formation About 290 tonnes of There is no residual The sludge disposal
sludge produced sludge. cost Rs. 3 lakhs
annually from this annually. This cost
treatment. is saved.
Structures and 11,000 Sq Mtrs of 3000 sq mtrs of tank About 75% of the
space. masonry tank for for containing and effluent treatment
evaporating the evaporating the facility space is
effluent effluent. released.
http://phycospectrum.com/moresnap.html

15. Phycoremediation is a multi-faceted effluent
treatment process. As a green cell factory algae can
tackle simultaneously more than one problem.
However, the development of more efficient
pollutants removal algal systems requires further
research in key areas.

16.  Bashan, L.E. and Bashan, Y., (2010). Immobilized Microalgae for Removing
Pollutants: Review of Practical Aspects. Bioresource Technology. 101: 1611–1627
 Davis, T.A., Volesky, B., and Mucci, A., (2003). A review of the biochemistry
of heavy metal biosorption by brown algae. Water Research., 37: 4311–4330
 Hallmann A. (2007) Algal Transgenics and Biotechnology. Transgenic Plant
Journal. 1: 81-98
 Kobayashi, H. and Rittman, B.E. (1982). Microbial removal of hazardous
organic compounds. Environ. Sci. Technol., 16: 70-183
 Torres, M.A., Barros M.P., Campos, S.C.G., Pinto, E., Rajamani, S., Sayre, R.T.
and Colepicolo, P. (2008). Biochemical Biomarker in Algae and Marine
Pollution: A review. Ecotoxicology and Environmental Safety. 71: 1-15
 http://phycospectrum.com/moresnap.html
 www.oldcastleprecast.com
 http://www.nasa.gov/centers/ames/greenspace/
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