BBM Medium Research Articles

Enhanced Scenedesmus obliquus Cultivation in Plastic-Type Flat Panel Photobioreactor for Biodiesel Production

A plastic-type flat panel photobioreactor (PTFPP) prototype was designed for microalgae cultivation as biodiesel feedstock. The growth, biomass, and lipid production of the oleaginous microalga Scenedesmus obliquus were optimized through the enhanced design and cultivation conditions in the PTFPP. The optimization conditions include cultivation of the microalga in a flat panel photobioreactor manufactured from a 10 µm-thick plastic sheet with dimensions of 40 cm in width and 60 cm in height. The width of the designed plastic bags was adjusted by “4 ports” of circular adhesion points which make the volumetric cultural capacity 5 L. Cultivation of the microalga was optimized through the replacement of the sodium nitrate of the BBM medium with urea as a nitrogen source. Cultivation bags were subjected to continuous illumination with 3000 lux white, fluorescent lamps and aerated with 1.5 L air/min (equal to 0.3 VVM). Biomass production from the designed PTFPP reached 3 g/L with around 40% lipid content (on a dry weight basis). Based on a GC-MS analysis of the produced fatty acid methyl ester (biodiesel) from S. obliquus, the percentage of C16 and C18 fatty acids reached more than 90% of the defined fatty acids. Out of this percentage, 66.6% were unsaturated fatty acids. The produced fatty acid profile of the S. obliquus biomass cultivated in the designed PTFPP prototype could be considered a suitable feedstock for biodiesel production.

Antioxidant Status and Biotechnological Potential of New Vischeria vischeri (Eustigmatophyceae) Soil Strains in Enrichment Cultures.

The functional state of enrichment cultures of the Eustigmatophycean strains Vischeria vischeri MZ-E3 and MZ-E4 after 25-day cultivation in the BBM medium was studied. The concentrations of chlorophyll a, total carotenoids, protein, vitamins A and E, fatty acid peroxidation product content, an antioxidant enzyme, and succinate dehydrogenase activity were measured. MZ-E3 succinate dehydrogenase activity was significantly higher by 2.21 times; the MZ-E4 strain had 2.94 times higher glutathione peroxidase activity. The MZ-E3 antioxidant activity index and the MZ-E3 unsaturation of fatty acids were 1.3 and 1.25 times higher than the MZ-E4. The retinol and α-tocopherol content of the MZ-E3 was 28.6% and 38.76% higher than MZ-E4. The main fatty acid profile differences were the 3.46-fold and 3.92-fold higher stearic and eicosapentaenoic acid content in the MZ-E4 biomass. MZ-E3 had higher antioxidant, energy, and metabolic and photosynthetic status than MZ-E4. The antioxidant status of the studied strains showed the dependence of the adaptive mechanisms of each, associated with differences in the ecological conditions of the biotopes from which they were isolated. These strains are promising for producing α-tocopherol and biomass enriched with omega-3 and omega-6 fatty acids.

Cultivation of Pseudochlorella pringsheimii for biodiesel production in a scalable indoor photobioreactor: case studies from Egypt

BackgroundEnhancement of lipid accumulation is the major strategy to improve the commercial feasibility of microalgae as a source for biodiesel production. Pseudochlorella pringsheimii (Formally was named as Chlorella ellipsoidea) green microalgae strain was chosen with respect to their ability as a potential source to produce high lipids content, could be used for the production of biofuel, which can be an alternative renewable energy source instead of fossil fuels. ResultsInitially, the Pseudochlorella pringsheimii microalgae was evaluated on the basis of tested at Lab scales 2 L by applicable different nutrient individual of N, P, Fe conditions in BBM medium concentrations for choosing the best concentrations induce lipid contents and productivity to cultivate in large scale in the 2000 L PBR. The suitable concentrations of nutrients with highest lipid contents were obtained under deficient of nitrogen (1.25 gL−1, limited N) and phosphorus (0.1 mg L−1, limited P) coupled with high iron concentration (10 mg L, rich Fe) and CO2 (6%). Therefore, their collective of nutrients was applied to culture of microalgae cells at large scale in 2000 L photobioreactor (PBR model), which, this techniques was used to quantify high lipid contents (25% w/w) and high lipid productivity (74.07 mgL−1 day−1). The inducted lipid conversion to biodiesel via transestrification process was 91.54 ± 1.43%. The fatty acid methyl esters (FAMEs profile by means of GC/MS resulted in C16:0, C18:1, C18:2, C18:3 as a main constituents. With regard to physical–chemical property (such as density, kinematic viscosity, gravity, and certain number), the Pseudochlorella pringsheimii biodiesel have biofuel properties, in accordance with appropriate biodiesel properties, as ASTM and EU standards, that thereby referring to high quality biodiesel. ConclusionsPseudochlorella pringsheimii cultured in large scale in photobioreactor under stress condition have a high potential of lipids production with high quality of FAMEs that can be used as a promising biodiesel fuel. It has also a potential to be applied for commercialization based on the techno-economic and environmental impacts. Highlights*Pseudochlorella pringsheimii showed a high potential of lipids 25% lipid accumulation.*Pseudochlorella pringsheimii could be cultured at large scale in potobioreactor, as potential feedstock for biodiesel production.*Bodiesel FAME contains C 16:0, C 18:1 and C 18:2 as a maim FAM.*N, P starvation collective with high Fe3+was the main driver behind lipid accumulation.*Pseudochlorella pringsheimii biodiesel have appropriate biodiesel properties, as ASTM and EU standards.*C. ellipsoidea can be used as a potential feedstock for biodiesel production.

Identification and Characterization of a New Microalga Dysmorphococcus globosus-HI from the Himalayan Region as a Potential Source of Natural Astaxanthin.

Simple SummaryThe natural astaxanthin from algae (marketed only 5%) is the most powerful antioxidant for health compared to the synthetic that shares about 95% of the market. Therefore, there is a huge demand for natural astaxanthin from algae, which can accumulate significantly higher astaxanthin. We have isolated a new algal strain from the Himalayan region, Northern India, which was identified as Dysmorphococcus globosus-HI based on morphological and molecular analysis. Its growth conditions were optimized in the laboratory. Among the seven different tested culture media, MBBM and 3N-BBM provided the maximum growth and astaxanthin production. The highest biomass production (1.14 g L−1) was observed in the modified BBM medium. It is an excellent source of producing natural astaxanthin, to a tune of 391 mg L−1, which is greater than any other known algal species. The productivity of astaxanthin was about 15.6 mg L−1 d−1 under normal conditions, which is higher than the commercially used H. pluvialis species. It is the first report of natural astaxanthin production from D. globosus-HI that has great potential for commercial application.Synthesized astaxanthin (ASX), stereoisomers of 3S,3′R, 3R,3′R, and 3S,3′S, have over 95% market share and have relatively poor antioxidant and bioactivity properties, with persistent issues in terms of biological functions, health benefits, and biosafety if compared to natural ASX. Bioprospecting of new microalgal strains could be vital for a new source of powerful antioxidant (ASX). In this study, a new algal strain was isolated from the Indian foothills of the Himalayas. Its identity was discerned by morphological and DNA barcode studies. It is a unicellular spheroidal cell-shaped alga with 100–200 μm diameter. The isolate has 93.4% similarity to Dysmorphococcus globosus species based on 18S-rDNA phylogenetic analysis and named as D. globosus-HI (HI stands for Himalayan India). Its growth and major cellular components (carotenoids, carbohydrates, protein, lipids, fatty acid profile, and ASX) were optimized using the seven different culture media. The highest biomass (1.14 g L−1) was observed in the MBBM medium, with a specific growth rate (0.087 day−1), division/day (0.125), and cellular yield (6.16 x 106 cells/mL). The highest carotenoids (1.56 mg g−1), lipids (32.5 mg L−1), and carbohydrates (135.62 mg L−1) were recorded in the 3N-BBM medium. The maximum ω3-FAs (17.78%), ω6-FAs (23.11%), and ω9-FAs (7.06%) were observed in MBBM, JW, and BG-11 medium respectively. The highest amount of antioxidant ASX was accumulated in the 3N-BBM medium (391 mg L−1). It is more than any other known algal species used in the production of natural ASX. The optimized biochemical studies on the D. globosus-HI strain should fulfill the increasing demand for natural ASX for commercial application.

Influence of culture medium on growth and protein production by Haematococcus pluvialis

Proteins from microalgal biomass have become promising raw materials in several industrial segments. To evaluate growth performance and protein production under different nutritional conditions, Haematococcus pluvialis was grown in different culture media: BBM, RM, BG-11, and KM2. The cultures were inoculated at 105 cells mL-1, and submitted to a temperature of 24°C, in a continous photoperiod and irradiance of 40 µmol photons m-2 s-1. The highest cell density was observed when H. pluvialis was maintained in BG-11 medium (142 ± 30 × 104 cells mL-1), but no statistical difference was observed when comparing the results with those obtained when culturing this microalga in BBM (101 ± 14 × 104 cells mL-1) and RM (105 ± 5 × 104 cells mL-1) media. Also, the lowest cell density was found when cultivating H. pluvialis in KM2 medium (57 ± 9 × 104 cells mL-1), and there was no statistical difference for doubling time, growth rate and specific growth rate results between treatments. In addition, higher protein contents in H. pluvialis were reported for RM, BG-11, and KM2 culture media at 55.1 ± 5.6, 49.3 ± 3.6 and 58.4 ± 2.8%, respectively; and lower protein content was found using the BBM medium (31.1 ± 2.9%). The highest cell density and biomass were achieved at greater nitrogen availability and a higher nitrogen to phosphorus ratio. The results suggest that H. pluvialis is a potential species for protein production, and that BG-11 is the most suitable medium for growing this microalga as it allowed the achievement of highest biomass production and protein content among the media evaluated.

The Green Microalga Coelastrella thermophila var. globulina (Scenedesmaceae, Chlorophyta) Isolated from an Algerian Hot Spring as a Potential Source of Fatty Acids.

Screening microalgae from extreme environments, including hot springs, is an important research topic that has lately emerged. A thermophilic green alga was isolated from a north-eastern Algerian hot spring at a temperature of 63 °C, and its fatty acid (FA) profile was explored. The strain was cultivated in BBM medium at 35 °C in a 16:8 h light/dark cycle and 75 μM photons m−2 s−1. The morphological studies combined with phylogenetic analysis revealed that the isolate was Coelastrella thermophila var. globulina Q. Wang, H. Song, X. Liu, G. Liu and Z. Hu. The monounsaturated fatty acid (MUFA) content was 51.12%. The saturated fatty acid (SFA) and polyunsaturated fatty acid (PUFA) content, respectively, accounted for 27.01% and 21.87%. The main FA was oleic acid (18:1n–9), whose value was 35.95%, followed in decreasing order by palmitic acid (16:0) with 21.45%, linoleic acid (18:2n–6) with 14.38% and α-linolenic acid (18:3n–3) with 04.22%. The FA profile exhibited high total n–6 and n–3 PUFA values (15.80% and 5.76%, respectively). Coelastrella thermophila var. globulina is particularly interesting for producing n-6 and n-3 PUFA and is likely suitable for other biotechnological purposes. This is the first time that this taxon has been reported in hot springs. Other species can be expected to be reported, which emphasises the importance of the biodiversity of extreme habitats.

Bioreactor Co-Cultivation of High Lipid and Carotenoid Producing Yeast Rhodotorula kratochvilovae and Several Microalgae under Stress.

The co-cultivation of red yeasts and microalgae works with the idea of the natural transport of gases. The microalgae produce oxygen, which stimulates yeast growth, while CO2 produced by yeast is beneficial for algae growth. Both microorganisms can then produce lipids. The present pilot study aimed to evaluate the ability of selected microalgae and carotenogenic yeast strains to grow and metabolize in co-culture. The effect of media composition on growth and metabolic activity of red yeast strains was assessed simultaneously with microalgae mixotrophy. Cultivation was transferred from small-scale co-cultivation in Erlenmeyer flasks to aerated bottles with different inoculation ratios and, finally, to a 3L bioreactor. Among red yeasts, the strain R. kratochvilovae CCY 20-2-26 was selected because of the highest biomass production on BBM medium. Glycerol is a more suitable carbon source in the BBM medium and urea was proposed as a compromise. From the tested microalgae, Desmodesmus sp. were found as the most suitable for co-cultivations with R. kratochvilovae. In all co-cultures, linear biomass growth was found (144 h), and the yield was in the range of 8.78–11.12 g/L of dry biomass. Lipids increased to a final value of 29.62–31.61%. The FA profile was quite stable with the UFA portion at about 80%. Around 1.98–2.49 mg/g CDW of carotenoids with torularhodine as the major pigment were produced, ubiquinone production reached 5.41–6.09 mg/g, and ergosterol yield was 6.69 mg/g. Chlorophyll production was very low at 2.11 mg/g. Pilot experiments have confirmed that carotenogenic yeasts and microalgae are capable of symbiotic co-existence with a positive impact om biomass growth and lipid metabolites yields.

Evaluation of the influence of different culture media on growth, life cycle, biochemical composition, and astaxanthin production in Haematococcus pluvialis

Haematococcus pluvialis is known as the richest natural source of carotenoid astaxanthin, whose synthesis is related to changes in cells according its complex life cycle and the availability of nutrients present in the culture media. This study’s objective was to evaluate the influence of different culture media under photoautotrophic and mixotrophic conditions on the growth, life cycle, biochemical composition, and astaxanthin production in H. pluvialis. Cultures were performed using the following media: KM1, MM2, Provasoli, modified Provasoli, and how to control the BBM, all kept at 24 ± 1 °C, with constant aeration, light/dark photoperiod 24:0 and irradiance of 60 μmol photons/m2/s. Growth and life cycle were evaluated by daily cell counts under an optical microscope; values of maximum cell density (MCD) and dry biomass were also assessed. Biochemical analyses were chlorophyll (a and b), astaxanthin, total proteins, and fatty acids. Cultivation under photoautotrophic conditions in BBM medium showed higher concentration of chlorophylls a (33 ± 4.0 μg/mL) and b (18 ± 1.6 μg/mL) and protein (62.7 ± 3.38%). Cultivation in modified Provasoli medium, under mixotrophic conditions, showed higher MCD (84.5 ± 11.7), biomass production (4.9 ± 0.0004 mg/mL), fatty acid methyl esters, and astaxanthin productivity (9.28 ± 0.4 mg/L/day). These results demonstrate that the culture media and the culture conditions to which H. pluvialis is submitted stimulate specific metabolic and biosynthetic pathways of the cells, which directly affect the biochemical composition of the microalgae. Modified Provasoli medium proved to be the most efficient in increasing astaxanthin productivity for this species, as it has shown better growth parameters and biomass production.

A New Species of Freshwater Algae Nephrochlamys yushanlensis sp. nov. (Selenastraceae, Sphaeropleales) and Its Lipid Accumulation during Nitrogen and Phosphorus Starvation

The new species Nephrochlamys yushanlensis sp. nov. is described from a freshwater plankton sample. A comparison of morphology, 18S rDNA gene and ITS2 sequences, and fatty acid profiles showed that the novel strain represents a new lineage within the genus Nephrochlamys. For the first time with a member of the Selenastraceae, experiments with phosphate and nitrate deprivation were conducted to evaluate changes in biomass, lipid and triacylglycerol (TAGs) accumulation, and composition of fatty acids. Biomass dry weight under simultaneous nitrogen and phosphorus depletion was 1.73g·L-1 , which is significantly lower than the 2.41g·L-1 observed in the control. All conditions of nutrient restriction significantly increased the lipid content in comparison with the control. The largest increase in the total lipid content, reaching 58.64% DW per cell at the end of cultivation, occurred with nitrogen deficiency. Significant increases in TAGs content (to 23.69% and 21.74%, respectively) occurred in phosphorus- and nitrogen-depleted conditions in comparison to the control (16.90%). Oleic (49.8-64.1%), palmitic (21.1-22.7%), and linoleic (8.6-10.3%) acids were the dominant fatty acids when cultured on standard BBM medium, as well as with the shortage of nutrients. Phosphorus deprivation as well as absence of both nitrogen and phosphorus led to the appearance of FAMEs α-linolenic (1.5-4.1%) and stearidonic (1.0-1.8%) acids. In general, FAME profiles revealed that the relative percentage of saturated and monounsaturated fatty acids increased (88.9% of total fatty acids) in nitrogen-depletion conditions, suggesting this strain may be suitable for biodiesel production.

Supplementing wastewater with NPK fertilizer as a cheap source of nutrients in cultivating live food (Chlorella vulgaris)

IntroductionThe decline in fishery resources from the wild has led to an ever increasing focus on aquaculture in recent years. With increasing aquaculture of animal species, there is an increasing need for suitable microalgae in the production of these animals. However, cultivation of microalgae in expensive pure chemical media is one of the major challenges facing large-scale cultivation of microalgae.PurposeThe present study investigated the suitability of aquaculture wastewater (AWW) supplemented with NPK (nitrogen:phosphorus:potassium) fertilizer as a cheap source of nutrient to cultivate a microalga Chlorella vulgaris (C. vulgaris).MethodsC. vulgaris with an initial cell density of 0.8 × 106 cells/mL was batch cultured in AWW supplemented with NPK at 0.1, 0.5, 1.0 g/L and BBM for 20 days under laboratory conditions using 2000 mL Erlenmeyer flasks. The proximate composition, chlorophyll, minerals, and vitamins analysis of C. vulgaris biomass were done using standard analytical methods.ResultsThe highest values in optical density (4.872 ± 0.025), dry cell weight (2.858 ± 0.015 g/L), specific growth rate (0.2097 ± 0.0038 day–1), and biomass productivity (0.1701 ± 0.0007 g/L/day) were obtained in C. vulgaris grown in AWW + 1.0 NPK medium. The total chlorophyll, protein, lipid, and carbohydrate content of the microalgae biomass were in the range of 0.05–0.862%, 44.062–57.089%, 17.064–23.260%, and 15.217–21.896%, respectively. Furthermore, microalgae grown in AWW + 1.0 NPK showed good vitamin and mineral content compared to BBM grown alga.ConclusionThese findings indicated that the AWW + 0.1 NPK, AWW + 0.5 NPK, and AWW + 1.0 NPK are potential growth media for C. vulgaris cultivation and can replace the BBM medium, which is very expensive and less accessible to users.

The effect of phosphorus starvation on the fatty acid composition of Visheria strains

Fatty acids are widely used in various fields: in medicine, agriculture, in the production of dietary supplement and biofuels, for the maintenance of aquaculture. The main source of fatty acids is fish oil. The relevance of the search for an alternative to fish oil as a source of fatty acids remains relevant today. Many microalgae accumulate fatty acids in quantities sufficient for use in biotechnology. Many studies are currently being conducted on the biochemistry of eustigmatophyceae algae. Most representatives of this class accumulate such polyunsaturated fatty acids as eicosapentaenoic and docosahexaenoic, which are in demand in biotechnology, while maintaining the necessary growth rates of biomass. The strains of Vischeria vischeri described in this work were isolated from soil samples. The obtained fatty acid profiles show that the strains when growing on a BBM medium with a triple nitrogen concentration store a high percentage of saturated palmitic, monounsaturated palmitoleic and polyunsaturated eicosopentaenoic acids. In addition, one of the strains accumulates rare long-chain polyunsaturated fatty acids: stearidonic acid, eicosodienoic acid, and digomo-γ-linoleic acid. Also, an experiment on phosphorus deprivation was conducted with these strains: as a result of this study, it was found that the composition of the fatty acids of the strains practically did not change, however, the concentrations of saturated and monounsaturated acids became higher, and polyunsaturated ones decreased. This trend in changes in the concentrations of fatty acids remained for all the described strains. The strains have been shown to accumulate long-chain saturated fatty acids: behenic and cerotic.

Development of High-Level Omega-3 Eicosapentaenoic Acid (EPA) Production from Phaeodactylum tricornutum.

Phaeodactylum tricornutum is a lipid-rich marine diatom that contains a high level of omega-3 polyunsaturated fatty acids, especially eicosapentaenoic acid (EPA). In an effort to reduce costs for large-scale cultivation of this microalga, this study first established a New BBM medium (0.3 x strength BBM with only 3% of the initial phosphate level) to replace the traditional F/2 medium. Phaeodactylum tricornutum could grow in extremely low phosphate concentrations (25µM), without compromising the EPA content. In the presence of sea salts, silicate addition was not necessary for high rate growth, high EPA content, or lipid accumulation in this species. Using urea as the sole nitrogen source tended to increase EPA contents per dry biomass (by 24.7%) while not affecting growth performance. The use of sea salts, rather than just sodium chloride, led to significantly improved biomass yields (20% increase) and EPA contents of total fatty acid (46-52% increase), most likely because it supplied sufficient essential elements such as magnesium. A salinity level of 35 led to significantly higher biomass yields compared with 20, but salinity had no significant influence on EPA content. EPA became the dominant fatty acid with average levels of 51.8% of total fatty acids during the exponential growth phase at 20 ppt in New BBM medium with sea salts.

Integration of bioelectricity generation from algal biophotovoltaic (BPV) devices with remediation of palm oil mill effluent (POME) as substrate for algal growth

The exploitation of renewable energy sources for delivering carbon neutral or carbon negative solutions has to be achieved through strategies involving the removal of CO2 from the atmosphere. Agro-industries like palm oil processing are important sources of energy but are also generators of large volumes of wastewater, causing pollution problems. Bioremediation of these effluents utilizing microalgae has shown promising results. In the present study, we developed an algal-biophotovoltaic device to generate direct bioelectricity from photosynthesis while using palm oil mill effluent (POME) as substrate for microalgal growth. Nine microalgal strains from the University of Malaya Algae Culture Collection (UMACC) were cultured using POME in four different concentrations (50%, 25%, 10%, and 5%) for 12 days. Chlorella vulgaris Beijerinck UMACC 051 showed the highest specific growth rate (1.32 d−1) and Chlorella UMACC 301 showed high photosynthetic performance (Alpha = 0.88) when grown in 5% POME–BBM medium. Three selected microalgal strains were grown in the control medium (Bold’s Basal Medium) and 5% POME–BBM medium in an annular biophotovoltaic device. The maximum power density (0.45 mW m−2) obtained from Chlorella UMACC 313 in the POME–BBM medium, was 15% higher than the power density generated when the microalgal cells were grown in the control medium (0.38 mW m−2). When Chlorella UMACC 313 was cultured in a 4L round integrated fuel cell-photobioreactor prototype device, the maximum power density obtained was 0.28 mW m−2. The reductions in NO3-N, o-PO43−, NH3-N and COD were 54.92%, 29.41%, 80.75 and 60.09% respectively. A final biomass of 810 mg L−1 was obtained after 12 days’ growth and the CO2 fixation rate was 76.82 mgCO2 L−1 d−1. This BPV system represents a multi-functional system that generates low power density while providing wastewater bioremediation and carbon removal. This has potential as a sustainable environment-friendly carbon-neutral or carbon-reducing energy generation system.

Comparative analysis of microalgae metabolism on BBM and municipal wastewater during salt induced lipid accumulation

This study showed that among stress factors, salinity has the greatest effect on accumulation of neutral lipids in microalgae strains that normally produce carbohydrates. Parachlorella kessleri IC-11 cultivation of autoclaved municipal wastewater with 30 g L−1 salt added revealed neutral lipids accumulation and increase in the total lipids content (up to 31.0 ± 1.8%). In saline wastewater P. kessleri IC-11 reduced COD by 11.46 ± 0.43%, while NH4+ was completely assimilated. PCA and PLS-DA analysis of its metabolism on BBM and wastewater revealed that the greatest contribution to the change in metabolism under salt stress was accomplished by a decrease in the following metabolites: adenylate (purine metabolism) on BBM medium and proline (arginine and proline metabolism) along with citric acid (citric acid cycle) on wastewater in stationary phase. Differences in metabolism during cultivation in both media should be taken into account when identifying potential target genes for metabolic engineering of lipid production in microalgae.

Isolation of some microalgae strains belonging to the family scenedesmaceas (chlorophyta) in freshwater bodies in central Vietnam and investigation into their biological characteristics

Seven microalgae strains from samples collected from freshwater lakes in Central Vietnam were isolated and cultivated in BBM medium for investigating their biological characteristics and their applicability. These strains were identified belonging to 6 species, 3 genera of the family Scenedesmaceae, division Chlorophyta. Their average growth rate was from 0.081 - 0.160 d-1, and the highest cell density of each strain reached from 2.6 x 106 - 60 x 106 cells/ml. The total content of pigments (including chlorophyll-a, chlorophyll-b, and carotenoid) of all strains was not too high (4.10 - 11.3 μg/mL), but the total lipid content exhibiting noticeably high levels, accounted for 16.6% - 74.1% of dry cell weight. Among isolated strains, Desmodesmusabundans and D.costato-granulatus were the most prominent with the highest growth rate and density in combination with remarkably high contents of lipids and pigments, and thus were identified as two potentially great candidates for biofuel production and chlorophyll and carotenoid extraction.

Optimization of Physical Parameters of Astaxanthin Production from Haematococcus pluvialis

Haematococcus pluvialis, fresh water microalgae has been considered as a possible natural source for the production of astaxanthin and it has been widely studied. The general composition of Haematococcus algae consists of common carotenoids, fatty acids, proteins, carbohydrates, and minerals. Both of the main physical and chemical parameters, especially medium and light, directly control the growth rate of Haematococcus pluvialis Astaxanthin is a keto-carotenoid which is built from five carbon precursors isopentenyl diphosphate (IPP) and dimethyl allyldiphosphate. Astaxanthin has important metabolic functions in animals and humans ranging from protection against oxidation of essential polyunsaturated fatty acids, protection against UV light effects, pro vitamin A activity and vision, immune response, pigmentation and communication to reproductive behaviour and improved reproduction. The astaxanthin is the pigment that is considered as the most powerful antioxidants in nature. Due to the high production cost of synthetic astaxanthin and the market demand for natural astaxanthin, the biological sources of astaxanthin have long been widely exploited. To extract more astaxanthin from Haematococcus pluvialis, Growth optimization of the microalgae was done by using various medium such as BG-11, Basal, RM, BBM and TAP Medium. This comprehensive study on the determination of the culture medium and the light intensity was carried out to maximize the growth of Haematococcus pluvialis for batch cultivations. optimization was done by using different pH, temperature and light. the chlorophyll and protein content were analysed. And finally the astaxanthin was produced. The protein content of H. Pluvialis was found to be 338.27µg/ml.

Biotechnological Potential of a New Strain of Bracteacoccus bullatus (Sphaeropleales, Chlorophyta) as a Promising Producer of Omega-6 Polyunsaturated Fatty Acids

A new strain of Bracteacoccus bullatus Fucikova, Flechtner et L.A. Lewis belonging to green algae has been isolated from forest litter at a locust plantation located in a steppe zone of Ukraine. The strain has been identified by its morphological characteristics and via a phylogenetic analysis using the 18S rDNA gene and the ITS1–5.8S rDNA–ITS2 region. The new strain has been put into the monophyletic B. bullatus clade with a high statistical support. The study of its growth and lipid accumulation rates has allowed for achieving a dry biomass and total lipid content equal to 2.31 g/L and 55.84%, respectively, after a 15-day cultivation on 3N BBM medium. The analysis of fatty acid composition of the strain has shown the prevalence of palmitic 16:0, hexadecadiene 16:2(7Z,10Z), oleic 18:1(9Z), and linoleic 18:2(9Z,12Z) acids, which comprise 91.9% of the total fatty acid content. Compared to other Bracteacoccus strains, the strain MZ–Ch32 demonstrates the maximum content of omega-6 polyunsaturated fatty acids. With allowance for its growth characteristics and fatty acid profile, the new strain of B. bullatus can be considered as a potential producer of essential linoleic or oleic acids. A balanced ratio of omega-3 and omega-6 polyunsaturated fatty acids in the biomass makes it possible to use the strain as a component of forage and feeding additives in agriculture.

Fatty Acid Content and Profile of the Novel Strain of Coccomyxa elongata (Trebouxiophyceae, Chlorophyta) Cultivated at Reduced Nitrogen and Phosphorus Concentrations.

A novel freshwater strain of Coccomyxa elongata (MZ-Ch64) was isolated from the Zaporizhia region, Ukraine. The identification was based on the phylogenetic analysis of SSU rDNA gene and ITS1-5.8S rDNA-ITS2 region and predicted secondary structure of the ITS2. Phylogenetic analysis placed this strain in the Coccomyxa group, within the class Trebouxiophyceae. The novel strain MZ-Ch64 formed a strongly supported lineage closest with C.elongata. The MZ-Ch64 strain differed from the morphological description of the species by the sizeof vegetative cells and absence of small mucilaginous caps at one end of the cell. A number of experiments with different concentrations of phosphate and nitrate were conducted to evaluate changes in the resulting fatty acid profiles and biomass productivity. The fatty acid profile and total fatty acids varied significantly under different nutrient deficiencies. The dominant fatty acid during cultivation on standard BBM medium, as well as in phosphorus-depleted conditions, was oleic acid (to 48.0%-54.6% of total fatty acids). Absence of nitrogen alone, and absence of both nitrogen and phosphorus, led to an increase of palmitic acid (to 24.7%-25.6%), cis-7-hexadecenoic acid (to 14.8%) and α-linolenic acid (to 9.1%-10.1%) in comparison with the control sample. The greatest variation was found for oleic acid (31.9%-54.6%). Thus, this strain can be considered as a potential producer of oleic acid or cis-7-hexadecenoic and α-linolenic acids for biotechnological applications.

PENAMBAHAN PUPUK KOMERSIAL PADA MEDIUM BBM UNTUK PERTUMBUHAN SPIRULINA PLANTENSIS DAN UJI AKTIVITAS ANTIOKSIDAN

The productivity and quality of Spirulina platensis is determined by the medium growth. One nutrient that can be used for growth Spirulina platensis microalgae are commercial fertilizers including Urea, ZA and TSP. The nitrogen contained in Urea and ZA fertilizers and phosphate in TSP fertilizer will used as an additional nutrient into the growth medium. This research aims to optimize the Spirulina platensis growth medium and test antioxidant activity. Spirulina platensis extract is obtained by sonication and maceration with methanol solvent. The antioxidant activity test was carried out withcalculate IC.50 by spectrophotometry by method1, 1-diphenyl-2-picrylhydrazyl (DPPH). The results showed that fertilizervariations ontreatments P1, P2, P3, P4, P5 and P6 provide optimum growthattreatment P5 (40% urea, 10% ZA and 40% TSP). Spirulina platensis growthon BBM, P5 and BBM medium combined with P5highest cell density on different days of growth. highest is availableon medium C (50% BBM + P5 50%) on day 11. Antioxidant activity inmedium C69,103m g / l, antioxidant activities are classified strong.

Non-lethal nitrate supplementation enhances photosystem II efficiency in mixotrophic microalgae towards the synthesis of proteins and lipids

The current study is aimed at understanding the effect of two different concentrations of nitrate (NaNO3) i.e., 2.94 mM (1X) and 8.82 mM (3X) on the productivity of Scenedesmus sp. in terms photosynthetic efficiency, growth, biomass and protein/lipid synthesis. The experiments were conducted by growing the microalgae in mixotrophic mode with a fixed dissolved organic carbon (110 mM). Chlorophyll a fluorescence fast kinetics parameter such as FV/FM, FM/FO, Pi_Abs, TRo/RC and ABS/RC depicted an improved PSII efficiency in 3X conditions. Higher nitrate concentration in BBM medium favored better assimilation of chlorophyll pigments, carbohydrates (160 mg/g), proteins (524 mg/g) and total lipids along with higher biomass (11.4 g/L). The microalgae cell growth, biomass and biochemical composition are significantly influenced by excess nitrates supplementation in the growth medium.