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Home / Chlorophyceae /
Colonies /Non-flagellated / Scenedesmus |
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Name derivation: |
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“Bound shelter” – Shelter Scene- bound –desmus |
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Classification:
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Scenedesmus Meyen 1829; 72 of 456 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013).
Order Sphaeropleales; Family Scenedesmaceae
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Morphology: |
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Mostly
elliptical single cells fuse together in rows, ranging from two to 32, with
spine like appendages on the outermost cells of the colony.
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Similar genera: |
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Fusola Snow 1903 is considered to be a synonym in this key.
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Photosynthetic
activity:
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When homocontinuous
Scenedesmus
cultures are grown under both high and low light intensities, it is revealed
that this genus displays similar characteristics to those of higher plants in
similar sun and shade conditions.
Under strong light conditions, photosynthetic capacity triples and
chlorophyll levels decrease, while chlorophyll levels in the low light
conditions doubles to compensate for the loss of absorbable wavelengths; this
increased chlorophyll content allows for the capture of more incident
light. Cultures in strong light
conditions also have higher respiration rates so the compensation point is
reached at a higher energy than that of the low light cultures (Senger and Fleischhacker 2006).
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Biodiesel:
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Various species of Scenedesmus, including S. abundans, are industrious raw materials for biodiesel production, an increasingly important field of research and interest. Due to its abundance in freshwater systems, Scenedesmus makes a great biodiesel candidate as it does not significantly nor negatively effect the environment when cultivated in large quantities. Under nitrogen concentrations of 0.32 g/L, the alga demonstrates optimal increases in biomass and lipid content, creating a biodiesel product that meets the criteria for the National Petroleum Agency, the European biodiesel standard, Germany’s standards, and South African standards (Mandotra et al. 2014).
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Growth
in Wastewater:
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It has been shown in multiple studies that various species of Scenedesmus can flourish in wastewater systems, increasing in biomass and potentially creating a sustainable system for simultaneous wastewater usage and biodiesel production. In one particular study, it was found that Scenedesmus grows at the highest rate in undiluted wastewater from a Bangkok noodle factory. Primary wastewater from aeration tank containing high suspended solids (MLSS) wastewater without dilution containing 5,500 mg SS/L and 189 mg total-N/L can promote high growth rate due to the high residual nutrients, allowing for MLSS to be used as culture media for microalgae (Whangchenchom et al. 2014).
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Habitat: |
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Distributed
globally (except Arctic and Antarctic Zones), mostly in eutrophic freshwaters but
rarely found in brackish water.
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References: |
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Mandotra, S.K., K. Pankaj, M.R. Suseelaa and P.W. Ramtekeb 2014. Fresh water green microalga Scenedesmus abundans: A potential feedstock for high quality biodiesel production. Bioresource Technology 156: 42-47. Meyen, F.J.F. 1829. Beobachtungen über einige niedere
Algenformen.
Nova Acta Physico-Medica
Academiae Caesareae Leopoldino-Carolinae Naturae 14:
768-778, pl. XLIII. Senger, H., and P.H. Fleischhacker 2006. Adaptation of the photosynthetic apparatus of Scenedesmus obliquus to strong and weak light conditions: differences in pigments, photosynthetic capacity, quantum yield and dark reactions. Physiologia Plantarum 40:35-42. Snow, J.W. 1903). The plankton algae of Lake
Erie. Bulletin of the United States Fish Commission 22:
371-394. Whangchenchom, W., W. Chiemchaisri, P. Tapaneeyaworawong and S. Powtongsook 2014. Wastewater from instant noodle factory as the whole nutrients source for the microalga Scenedesmus sp. cultivation. Environmental Engineering Research; 19: 283-287. |
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