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Morphology, composition, production, processing and applications of Chlorella vulgaris: A review Carl Safi, Bachar Zebib, Othmane Merah, Pierre-Yves Pontalier, Carlos Vaca-Garcia To cite this version: Carl Safi, Bachar Zebib, Othmane Merah, Pierre-Yves Pontalier, Carlos Vaca-Garcia. Morphology, composition, production, processing and applications of Chlorella vulgaris: A review. Renewable and Sustainable Energy Reviews, Elsevier, 2014, 35, pp.265-278. 10.1016/j.rser.2014.04.007. hal- 02064882 HAL Id: hal-02064882 https://hal.archives-ouvertes.fr/hal-02064882 Submitted on 12 Mar 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible This is an author’s version published in: http://oatao.univ-toulouse.fr/23269 Official URL: https://doi.org/10.1016/j.rser.2014.04.007 To cite this version: Safi, Carl and Zebib, Bachar and Merah, Othmane and Pontalier, Pierre- Yves and Vaca-Garcia, Carlos Morphology, composition, production, processing and applications of Chlorella vulgaris: A review. (2014) Renewable and Sustainable Energy Reviews, 35. 265-278. ISSN 1364-0321 Any correspondence concerning this service should be sent to the repository administrator: [email protected] Morphology, composition, production, processing and applications of Chlorella vulgaris: A review a b a b a b a b Carl Safi , ,*, Bachar Zebib , , Othmane Merah , , Pierre-Yves Pontalier , , a b c Carlos Vaca-Garcia , , a Université de Toulouse, INP-ENSIACET, LOI (Laboratoire de Chimie Agro-industrielle), F-31030 Toulouse, France b INRA, UMR 1010 GII, F-31030 Toulouse, France c King Abdulaziz University,Jeddah, Saudi Arabia ARTICLE INFO ABSTRACT E conomie and te chnical problems related to the redu ction of petroleum resources require the valorisation of renewable raw material. Re cently, microalgae emerged as promising alternative feedstock Keywords; Chlorella vulgaris that represents an enormous biodiversity with multiple benefitsex ceeding the potential of conventional agricultural feedstock.Thus, this comprehensive review arti cle spots the light on one of the most Algo-refinery Chlorella vulgaris. Growth conditions interesting microalga It assembles the history and a thorough des cription of its Morphology ultrastructure and composition a ccording to growth conditions.The harvesting te chniques are presented Primary composition in relation to the nove! algo-refinery concept, with their te chnological advan cements and potential Production applications in the market. Contents 1. Introdu ction ........................................................................................................ 266 2. Morphology ........................................................................................................ 266 2.1. Cell wall . .. .. .. 267 2.2. Cytoplasm . .. .. 267 2.2.1. Mitochondrion ......................................................................................... 267 2.2.2. Chloroplast ............................................................................................ 267 3. Reprodu ction ....................................................................................................... 267 4. Produ ction ......................................................................................................... 267 4.1. Autotrophi c growth .. .. 268 4.1.1. Open pond systems ..................................................................................... 268 4.1.2. Closed photo-biorea ctor ................................................................................. 268 4.2. Heterotrophic growth . .. .. 268 4.3. Mixotrophi c growth ............................................................................................ 268 4.4. Other growth techniques . .. .. 268 4.5. Harvesting . .. .. 269 4.5.1. Centrifugation ......................................................................................... 269 4.5.2. Flocculation ........................................................................................... 269 4.5.3. Flotation .............................................................................................. 269 4.5.4. Filtration .............................................................................................. 269 5. Primary composition ................................................................................................. 269 5.1. Proteins . .. .. 269 5.2. Lipids ....................................................................................................... 270 * Corresponding author at: Université de Toulouse, INP-ENSIACET, LCA (Laboratoire de Chimie Agro-industrielle), F-31030 Toulouse, France. Tel.: +33 6 50 45 29 65. E-mail address: [email protected] (C. Safi). http:/ /dx.doi.org/10.1016/j.rser.2014.04.007 5.3. Carbohydrates . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 271 5.4. Pigments . .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 271 5.5. Minerais and vitamins .......................................................................................... 271 6. Cell disruption techniques.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 272 7. Applications and potential interests . .. .. .. .. .. .. .. .. .. .. .. .. 272 7.1. Biofuels...................................................................................................... 272 7.2. Human nutrition .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 27 3 7.3. Animal feed. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 27 3 7.4. Wastewater treatment.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 27 4 7.5. Agrochemical applications.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 27 4 8. Algo-refineryconcept ................................................................................................ 275 9. Conclusion ......................................................................................................... 275 Acknowledgements ...................................................................................................... 275 References............................................................................................................. 275 1. Introduction conflict with food production [16] and especially would not cause deforestation. Microalgae have an ancient history that left a footprint 3.4 bil­ Microalgae represent an enormous biodiversity from which lion years aga, when the oldest known microalga, belonging to the about 40.000 are already described or analysed [17]. One of the group of cyanobacteria, fossilised in rocks of Western Australia. most remarkable is the green eukaryotic microalga C. vulgaris, Studies confirmed that until our days their structure remains which belongs to the following scientific classification: Domain: unchanged and, no matter how primitive they are, they still Eukaryota, Kingdom: Protista, Divison: Chlorophyta, Class: Tre­ represent rather complicated and expertly organised forms of life bouxiophyceae, Order: Chlorellales, Family: Chlorellaceae, Genus: [1 ]. Nevertheless, other reports estimated that the actual time of Chlorella, Specie: Chlorella vulgaris. Hence, Martinus Willem Bei­ evolution of cyanobacteria is thought to be doser to 2.7 billion jerinck, a Dutch researcher, first discovered it in 1890 as the first years aga [2,3]. Hence, evolutionary biologists estimate that algae microalga with a well-defined nucleus [18]. The name Chlorella could be the ancestors of plants.Thus, through time algae gave rise cornes from the Greek word chloras (XÀ.rup6ç;), which means to other marine plants and moved to the land during the green, and the Latin suffix el/a referring to its microscopie size. lt Palaeozoic Age 450 millions years aga just like the scenario of is a unicellular microalga that grows in fresh water and has been animais moving from water onto land. However, evolutionists present on earth since the pre-Cambrian period 2.5 billion years need to overcome multiple obstacles ( danger of drying, feed, aga and since then its genetic integrity has remained constant [ 1 ]. reproduction, and protection from oxygen) to definitely confirm By the early 1900s, Chlorella protein content ( > 55% dry weight) this scenario complemented with more scientific evidence. attracted the attention of German scientists as an unconventional Like any other phytoplankton, microalgae have a nutritional food source. In the 1950s, the Carnegie Institution of Washington value. The first to consume the blue green microalga were the [19] took over the study and managed to grow this microalga on a Aztecs and other Mesoamericans, who used this biomass as an large scale forCO 2 abatement. Nowadays, Japan is the world leader important foodsource [4]. Nowadays, these microscopie organisms in consuming Chlorella and uses it for medical treatment [20,21] are still consumed as foodsupplement such as Chlorellavulgaris and because it showed to have immune-modulating and anti-cancer Spirulina platensis [5] and their products are also used
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