Production Of Spirulina Platensis Research Articles

Effect of different recycled fisheries and domestic waste compost on the production of Spirulina platensis

Effect of different recycled fisheries and domestic waste compost on the production of Spirulina platensis

Smart Production of Lipids as Bio-Fuel in Spirulina Platensis (=Arthrospira Fusiformis), and Bio-Oxygen and Bio-Electricity in Media Cultured in Supernatant of Digested Poultry Waste

An experiment was conducted to evaluate growth performances and production of bio-fuel of Spirulina platensis (Gomont), and bio-oxygen and bio-electricity of culture media in supernatant of three different amount of digested poultry waste (DPW), and Kosaric medium (KM) as control. Three different amounts (concentrations) such as 2.0, 4.0 and 6.0 g/L poultry waste were allowed to digest under aeration. After 17 days, 700 ml grayish coloured supernatant was taken with addition of 9.0 g/L NaHCO3 and 0.50 ml/l micronutrient in 2.0 L conical flask with three replications and then autoclaved. Spirulina was inoculated to grow in these three treatments including KM (Control) after 72 hours of autoclave and then allowed to grow for a period of 14 days. This duration was estimated through repeated growth trials. The cell weight of spirulina was attained a maximum of 12.58 ± 1.25 mg/L (dry wt. basis) in KM followed by 11.46 ± 1.03, 9.16 ± 0.84 and 8.13 ± 0.73 mg/L in supernatant of 4.0, 2.0 and 6.0 g/L DPW, respectively on the 10th day of culture. Similar trend was also observed in the cases of optical density of the media contained spirulina, chlorophyll a content (mg/L), cell weight, total biomass (mg/l) and specific growth rates on the basis of cell weight and chlorophyll a. Cell weight of spirulina grown in these media had highly significant (P < 0.01) correlation with the chlorophyll a content (r = 0.993) of spirulina. Crude protein of spirulina grown in supernatant of DPW was lower than that of spirulina cultured in KM. Crude lipids as bio-fuel of spirulina cultured in supernatant of 4.0 g/L DPW was almost three times higher than that of spirulina grown in KM which may be due to high phospholipids bioaccumulation. Phosphate-P was decreased in media of DPW due to its use for high lipids biosynthesis as phospholipids. Bio-oxygen was produced higher ranged from 2.1 ± 11 mg/L on initial day to 10.20 ± 0.54 mg/L on 10th day grown in supernatant of 4.0 g/L DPW media. Bio-electricity as green electricity ranged from 135 ± 4 on initial day to 284 ± 7 mV on 10th day when spirulina cultured in supernatant of 4.0 g/L DPW which was higher than grown in other media. pH followed the similar trend like bio-oxygen and bio-electricity. It was found that the production of bio-oxygen, bio-fuel and bio-electricity had direct relation with pH in culture media of spirulina. Therefore, mass production of Spirulina platensis might be done in supernatant of 4.0 g/L digested poultry waste to get high total lipids as bio-fuel, bio-electricity and bio-oxygen.

The use of vermicompost in cultivation and production of Spirulina platensis

The cyanobacterium Spirulina platensis is quite spread all over the world due to its high nutritional value. It has been used as protein source and vitamin supplement in healthy diet, in aquaculture and fisheries. Cyanobacterium Spirulina is capable to grow in various kinds of culture media. Furthermore, decomposed organic and inorganic nutrients media have been proven to be good source of culture medium for Spirulina by many researchers. In this work, S. platensis was cultivated using dry vermicompost from fish sludge (VCFS) or cow manure (VCCM). 100 g of dry vermicompost from each source (VCFS/VCCM) collected and compared with Aiba and Ogawa liquid medium which was used as culture medium. The results obtained showed that the highest protein and chlorophyll a ratio of S. platensis were observed in the biomass harvested from T2 (VCCM) and T3 (Aiba and Ogawa liquid medium). The highest dried S. platensis biomass was harvested from T2 (VCCM) while the lowest came from T1 (VCFS). The chemical composition ( as % of dry weight) revealed that (VCCM) was higher in total phosphorus, total nitrogen and organic matter than (VCFS).

Protein accumulation and expression of the nitrate reductase gene in Spirulina platensiscells depending on the spectral composition of led radiation

The effect of LED lighting of different spectral composition on the productivity of Spirulina platensis, an accumulation of protein in alga cells and an expression of the nitrate reductase gene has been studied. It was shown that LED lighting with a predominance of the red component in the emission spectrum allows achieving 9–29 % higher alga productivity compared to using fluorescent lamp illumination. Illumination with single blue light resulted in significant (83 %) decrease in the productivity of Spirulina platensiswhich apparently was due to the absence of the yellow and red components in the illuminator spectral composition, which are most effectively absorbed by phycocyanin. A positive correlation between an increase in the productivity of alga and the accumulation of protein in its cells was found. So, by using an illuminator with red LEDs, the protein content increased by 21 % calculated per gram of dry weight and 47 % calculated per liter of suspension relative to the control. Analysis of the expression of the Nar gene encoding nitrate reductase in Spirulina platensiscells did not reveal a direct dependence between an increasing protein accumulation and an expression level of the Nar gene in the most promising in terms of biomass and protein yield sample of alga, growing under red LEDs. This indicates the crucial role of the photosynthetic activity of Spirulina platensiscells in increasing productivity and protein synthesis.

English

In this study, dry chicken manure (DCM) was used as the source of nitrogen in the production of Spirulina platensis . Experiment was conducted in two different types of nutrition. In the type I nutrition, the highest average cell increase was recorded as 289.70 filaments mL -1 in value in the type I group (DCM+urea). In the type II nutrition, the highest average cell increase was recorded as 296.50 filament mL -1 in value in the type II group (DCM+urea+sodium bicarbonate). In the type I nutrition (DCM+Urea), the highest specific growth rate was detected as 0.21 division day -1 on the sixth day and k value as being 0.30 division day -1 . In the type II nutrition, the highest specific growth rate was recorded as 0.08 division day -1 in the group II (DCM+Urea+NaHCO 3 ) and k value as being 0.12 division day -1 . In both types of nutrition, the protein rates of the type I group (DCM+urea) and the group III (DCM+sodium bicarbonate) are found to be higher than that in the other groups. The lipid levels in both types of nutrition, in DCM (Control) and in the type I group (DCM+Urea) were found to be higher than the other groups. Keywords: Spirulina platensis, dry chicken manure, sodium bicarbonate, urea African Journal of Biotechnology , Vol 13(14), 1597-1603

Modeling on chlorophyll a and phycocyanin production by Spirulina platensis under various light-emitting diodes

Light-emitting diodes (LEDs) with various light wavelengths (red, yellow, green, blue and white) and various levels of light intensity (750, 1500 and 3000 μmol m −2 s −1) are applied to study the effects of light sources on chlorophyll a (Chl) and phycocyanin (Phy) production of Spirulina platensis. Logistic rate equations are used to depict the kinetic behavior of algal growth and pigments formation under various light sources and intensities. According to the regression results, a red LED is the best for algae growth. On the other hand, yellow light gives the best specific Chl production rate with a light intensity of 750 or 1500 μmol m −2 s −1, and blue light yields the best specific pigments (for Chl and Phy) production rates at 3000 μmol m −2 s −1. From the model fitting results, it is found that, at a higher light intensity, a higher specific Chl production rate accompanied by a higher S. platensis biomass is obtained. However, as for Phy production, a higher biomass results in a lower specific Phy production rate. The only exception is the use of blue light, which shows a positive effect on both Chl and Phy production rates under a higher light intensity.

Optimal tilt angles of enclosed reactors for growing photoautotrophic microorganisms outdoors

The relationship between the tilt angle of a flat-plate photobioreactor and productivity of Spirulina platensis was evaluated along with the annual seasons under the climatic conditions of south Israel (latitude approx. 31°). The reactor tilt angle exerted a significant effect on the optimal population density and thus on the productivity of cell mass, owing to its control over the amount of solar radiation entering the reactor. A direct relationship between solar energy and productivity was observed: the higher the amount of solar energy that was admitted by varying the reactor tilt angle according to season, the higher was the productivity that could be sustained in the culture. Small tilt angles of 10° to 30° in summer and larger angles in the vicinity of 60° in winter resulted in maximal productivities for these seasons. Photosynthetic efficiency was calculated for the different tilt angles for all seasons. Efficiency was low in the winter due to temperature limitations. In summer it was highest in the 90° reactors, indicating that for optimal tilt angles in this season (in regards to productivity) a significant amount of radiation could not be effectively used by the culture. The results suggest a potential benefit in orientating and tilting reactors at various appropriate angles to the sun on a seasonal basis: up to 35% enhancement in annual output rate is estimated to be achievable.

Quantitative assessment of the major limitations on productivity ofSpirulina platensis in open raceways

This work represents an attempt to assess the relative contribution of the factors limiting productivity ofSpirulina platensis in open raceways throughout the year. Temperature of the culture during daylight exerted the predominant effect on productivity and elevating the temperature resulted in a significant rise in productivity even in summer. Photoinhibition had a decisive role in summer in determining productivity ofSpirulina in open raceways in that growth almost ceased after mid-day. Contamination by other microorganisms, particularlyS. minor andChlorella sp. was estimated to reduce the net biomass yield by at least 15 to 20%, but measures to curtail the establishment of these species in the raceway have been devised. The effect of harvest time during the day on the yield of dry mass was examined: no conclusion could be drawn except in mid-summer, when evening harvesting resulted in a significant increase in the output rate of dry weight over morning harvesting.