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Evolution of chlorophyll and primary carotenoid content of Coelastrella sp. S6 cells at day 4 of the growth phase (phase 1) and at days 0, 1, 2, 3, 4, and 15 of the stress phase (phase 2), in different conditions. Chls = Chlorophylls, PC = Primary Carotenoids (see text for details). Phototrophic conditions: (a) Cells were cultivated under "Air" during the growth phase; (b) Cells were cultivated under "CO2" during the growth phase. Heterotrophic conditions: (c) Condition 1; (d) Condition 2. The data are reported as the mean ± standard deviation from three independent biological replicates.
Source publication
Considering the importance of microalgae as a promising feedstock for the production of both low-and high-value products, such as lipids and pigments, it is desirable to isolate strains which simultaneously accumulate these two types of products and grow in various conditions in order to widen their biotechnological applicability. A novel freshwate...
Contexts in source publication
Context 1
... evolution of the primary pigment content at day 4 of the growth phase (phase 1) and during the "reddening" phase (i.e., carotenogenesis, phase 2), normalized on dry weight (DW), is presented in Figure 5a and b using the methodology described in the Section 2.7 of the Materials and Methods Section. Two classes of primary pigments were considered: Chlorophylls (Chls = chlorophylls a + b) and Primary Carotenoids (PC = neoxanthin + violaxanthin + antheraxanthin + lutein + zeaxanthin + β-carotene). ...
Context 2
... classes of primary pigments were considered: Chlorophylls (Chls = chlorophylls a + b) and Primary Carotenoids (PC = neoxanthin + violaxanthin + antheraxanthin + lutein + zeaxanthin + β-carotene). Primary pigment content did not change between day 4 of the growth phase and day 0 of the reddening phase, whatever the cultivation condition of the growth phase (Air or CO2) (Figure 5a,b). However, the presence of CO2 had an impact on the pigment content. ...
Context 3
... evolution of the primary pigment content at day 4 of the growth phase in heterotrophy and during the reddening phase is presented in Figure 5c,d. These contents were higher at day 4 of the growth phase than at day 0 of the reddening phase, which could be related to a nitrate deficiency already established during the growth condition (at day 9 of the culture, Figure 3b). ...
Citations
... 16 This genus is also reported to be a great source of fatty acids. 42 Members of Coelastrella are producers of carotenoids 43 that have antioxidant and anti-inflammatory effects. 44 The Zaqeq 32 and Ziglap 30 samples isolated in this study were identified as Monoraphidium sp. ...
In light of the rapid and extreme changes in climate and the steady depletion of natural resources, there is an urgent need to find innovative and sustainable solutions to these problems. Microorganisms such as microalgae can offer viable solutions to these challenges. Proper investment in such organisms requires the identification of the algal species that inhabit the region. Therefore, this study aimed to isolate and molecularly characterize green microalgae that inhabit freshwater at different locations in the governorates of Irbid and Ajloun in the northern region of Jordan. Water samples collected from these regions were used to isolate single colonies, some of which exhibited different morphological characteristics. Genomic DNA was extracted from the isolates and used as a template for PCR amplification of the 18S ribosomal DNA gene (18S rDNA) and the internal transcribed spacer (ITS) region. Phylogenetic trees were constructed based on 18S rDNA and ITS PCR product sequences, which were used to identify the isolates at the genus level. The obtained isolates belonged to three genera; Coelastrella, Desmodesmus, and Monoraphidium. The latter species has not been previously reported in Jordan.
... Previous studies reported that the photoautotrophic cultivation of Coelastrella spp. with 1.5-5.0% CO2-supplemented air yielded 1.2 to 4 times higher biomass concentrations [53,54]. Coelastrella sp. ...
... Previous studies reported that the photoautotrophic cultivation of Coelastrella spp. with 1.5-5.0% CO 2 -supplemented air yielded 1.2 to 4 times higher biomass concentrations [53,54]. Coelastrella sp. ...
... were reported to accumulate high contents of polyunsaturated fatty acids (45.6-65.2%) under photoautotrophic cultivation [8,53,68,69]. In contrast, the mixotrophic cultivation of Coelastrella spp. ...
Improving biomass production with the utilization of low-cost substrate is a crucial approach to overcome the hindrance of high cost in developing large-scale microalgae production. The microalga Coelastrella sp. KKU-P1 was mixotrophically cultivated using unhydrolyzed molasses as a carbon source, with the key environmental conditions being varied in order to maximize biomass production. The batch cultivation in flasks achieved the highest biomass production of 3.81 g/L, under an initial pH 5.0, a substrate to inoculum ratio of 100:3, an initial total sugar concentration of 10 g/L, and a sodium nitrate concentration of 1.5 g/L with continuous light illumination at 23.7 W/m2. The photobioreactor cultivation results indicated that CO2 supplementation did not improve biomass production. An ambient concentration of CO2 was sufficient to promote the mixotrophic growth of the microalga as indicated by the highest biomass production of 4.28 g/L with 33.91% protein, 46.71% carbohydrate, and 15.10% lipid. The results of the biochemical composition analysis suggest that the microalgal biomass obtained is promising as a source of essential amino acids and pigments as well as saturated and monounsaturated fatty acids. This research highlights the potential for bioresource production via microalgal mixotrophic cultivation using untreated molasses as a low-cost raw material.
... The strain Coelastrella sp. S6 [176] isolated from an open pond in the Liège region (Belgium), Coelastrella sp. BGV from a metal tub found in the village Varvara (Bulgaria) [177] and the strain Coelastrella sp. ...
Microalgae are the richest source of natural carotenoids, which are valuable pigments with a high share of benefits. Often, carotenoid-producing algae inhabit specific biotopes with unfavorable or even extremal conditions. Such biotopes, including alpine snow fields and hypersaline ponds, are widely distributed in Europe. They can serve as a source of new strains for biotechnology. The number of algal species used for obtaining these compounds on an industrial scale is limited. The data on them are poor. Moreover, some of them have been reported in non-English local scientific articles and theses. This review aims to summarize existing data on microalgal species, which are known as potential carotenoid producers in biotechnology. These include Haematococcus and Dunaliella, both well-known to the scientific community, as well as less-elucidated representatives. Their distribution will be covered throughout Europe: from the Greek Mediterranean coast in the south to the snow valleys in Norway in the north, and from the ponds in Amieiro (Portugal) in the west to the saline lakes and mountains in Crimea (Ukraine) in the east. A wide spectrum of algal secondary carotenoids is reviewed: β-carotene, astaxanthin, canthaxanthin, echinenone, adonixanthin, and adonirubin. For convenience, the main concepts of biology of carotenoid-producing algae are briefly explained.
... The surface topology of the cells was visible in SEM images, the cells exhibiting meridional ribs that run from one pole to the other (Figure 1d). These features have been described for other Coelastrella species and are evidently typical of the genus [18,20,21,23,24]. ...
In this study, the effect of media composition, N/P ratio and cultivation strategy on the formation of carotenoids in a Coelastrella sp. isolate was investigated. A two-stage process utilizing different media in the vegetative stage, with subsequent re-suspension in medium without nitrate, was employed to enhance the formation of carotenoids. The optimal growth and carotenoid content (β-carotene and lutein) in the vegetative phase were obtained by cultivation in M-8 and BG11 media. Use of a N/P ratio of 37.5 and low light intensity of 40 μmol m−2 s−1 (control conditions) led to optimal biomass production of up to 1.31 g L−1. Low concentrations of astaxanthin (maximum of 0.31 wt. %) were accumulated under stress conditions (nitrogen-deficient medium containing 1.5 % of NaCl and light intensity of 500 μmol m−2 s−1), while β-carotene and lutein (combined maximum of 2.12 wt. %) were produced under non-stress conditions. Lipid analysis revealed that palmitic (C16:0) and oleic (C18:1) constituted the main algal fatty acid chains (50.2 ± 2.1% of the total fatty acids), while esterifiable lipids constituted 17.2 ± 0.5% of the biomass by weight. These results suggest that Coelastrella sp. could also be a promising feedstock for biodiesel production.
... Glass beads were added to the sample and cells were disrupted through horizontal agitation in a TissueLyser II (Qiagen, Hilden, Germany) for 2 × 5 min at 30 Hz. Fatty Acid Methyl Esters (FAMEs) were generated from the microalgal biomass as described in Corato et al. (2022). FAMEs quantification was performed using gas chromatography (GC, Shimadzu, Tokyo, Japan) and a flame ionization detector (FID, Shimadzu) as mentioned in Gérin et al. (2020). 1 µl of sample was injected on a SGE BPX70 column (30 m × 0.25 mm × 0.25 µm) in "split" mode with a ratio of 10. ...
Global energy demand and fossil fuels impact on climate can be partially managed by an increase in the use of biofuels for transports and industries. Biodiesel production is generally preceded by a transesterification process of the green biomass triacylglycerols that generates large amounts of glycerol as a by-product. In this study, the extremophilic red microalga Galdieria sulphuraria 074W was cultivated in heterotrophy. The microalgal growth parameters and biomass composition were compared when grown on an equivalent molar concentration of carbon of either glucose or glycerol as unique carbon source. The maximal biomass reached in these two conditions was not significantly different (∼2.5 g.L–1). Fatty acid profile, protein and storage carbohydrate contents were also statistically similar, irrespectively of the metabolized carbon source. We also observed that the pigment content of G. sulphuraria cells decreased during heterotrophic growth compared to photoautotrophic cultivated cells, and that this diminution was more important in the presence of glucose than glycerol: cells were yellowish in the presence of glucose and green in the presence of glycerol. The pigmentation was restored when glucose was totally consumed in the medium, suggesting that the presence of glucose repressed pigment synthesis. Based on this observation, a transcriptome analysis was performed in order to better understand the mechanisms involved in the loss of color mediated by darkness and by glucose in G. sulphuraria. Three conditions were analyzed: heterotrophy with glycerol or glucose and phototrophy. This allowed us to understand the transcriptional response of cells to light and dark environments both at the nuclear and chloroplast levels, and to show that transcription of gene families, acquired by horizontal gene transfer, such as sugar, amino acid, or acetate transporters, were involved in the response to the availability of different (in)organic sources.
Extremophile environments are an important source for finding microorganisms with a potential for biotechnological applications. Among these microorganisms, microalgae contribute to several sustainable processes such as wastewater treatments or nutrition. In this work it was characterized a microalga isolated from a solar panel. The morphological and phylogenetic analysis revealed that the isolate collected was a Coelastrella strain. Cultivation and stress experiments has shown that Coelastrella sp. D14 can resist a long period of desiccation and it can grow on cheap sources such as piggery wastewaters (PWW). This work reports that a Coelastrella strain displays biostimulant properties with a germination index of 123% on Lepidium sativum when D14 biomass grown at 10% piggery effluent was used. Altogether, these results suggest that this novel strain could be a good chassis for further biotechnological applications.
Highlights
Coelastrella sp. D14, a xero-tolerant strain, has been isolated from a solar panel
This strain can grow on piggery wastewater
Coelastrella sp. D14 can promote germination of Lepidium sativum
Canthaxanthin is an orange-red keto-carotenoid that occurs naturally and is also manufactured by synthetic methods for regular applications. In nature, canthaxanthin mainly exists in microbes such as different bacterial species, fungi, and algae, as well as in animals such as crustaceans, certain fishes, and birds. However, the amount of canthaxanthin produced in these organisms varies significantly. Additionally, the compound can be generated from genetically modified organisms using genetic engineering techniques Canthaxanthin finds extensive application as an additive in animal feed, in the pharmaceutical industry, as a coloring agent for various food products, and in cosmetics. It has powerful antioxidant properties and plays a role in lipid metabolism, neuroprotection, and immunomodulation. This article gives an extensive insight into the structure and methods of synthesis of canthaxanthin along with its various newly discovered sources identified so far. The significant applications of canthaxanthin, particularly its role in pharmaceuticals, are critically evaluated. Furthermore, the article discusses future aspects and challenges associated with canthaxanthin production and regulation.
Microalgal conversion of high-level CO2 in industrial flue gas to value-added products is attractive technology for mitigating global warming. However, reduction of microalgal production costs for medium ingredients, particularly nitrogen salts, is essential. The use of atmospheric nitrogen as a nitrogen source for microalgal cultivation will dramatically reduce its production costs. We attempted to enrich a microalga-bacteria community, which fixes both CO2 and atmospheric nitrogen under high level CO2. By cultivating biofilm recovered from the surface of cobbles in a riverbank, a microalgal flora which grows in a nitrogen salts-free medium under 10% CO2 was enriched, and the coccoid microalgal strain MP5 was isolated from it. Phylogenetic analysis revealed that the strain MP5 belongs to the genus Coelastrella, and the closest known species was C. terrestris. With PCR-DGGE analysis, it was found that the enriched microalgal community includes bacteria, some of which are suggested diazotrophs. The addition of bactericides in culture medium inhibited MP5 growth, even though the strain MP5 is eukaryotic. Growth of bacteria-free MP5 was stimulated by addition of Agrobacterium sp. isolates in nitrogen salts-free medium, suggesting that MP5 and the bacteria have responsibility for photosynthetic carbon fixation and nitrogen fixation, respectively.
