Effects of Nutrient Supply Methods and Illumination with Blue Light Emitting Diodes (LEDs) on Astaxanthin Production by Haematococcus pluvialis

Abstract

In order to increase the cell concentration and the accumulation of astaxanthin, the effects of nutrient concentration, pH, illumination and methods of supplying nutrients were studied for the cultivation of Haematococcus pluvialis. The replacement of media to avoid the deficiency of nutrients increased the cell concentration above 1 mg-dry cell cm(-3) without induction of astaxanthin accumulation. Illumination with blue light emitting diode lamps and nutrient starvation induced accumulation of astaxanthin, and the interactive effects of these two increased the astaxanthin concentration to 76 mug cm(-3).

Study of Electrochemical Behaviour of Carotenoids in Aqueous Media

“…Namely, a precipitate of standard (astaxanthin, lutein and b-carotene) was formed onto the surface of PIGE by placing 5 mL of pure standard solution in acetone and allowing the solvent to evaporate in air. Furthermore, acetone was shown to be one of the best solvents for extraction of carotenoids [26] and is far less toxic then some other organic solvents. Different concentrations of standards were tested depending on solubility of each compound in acetone.…”

“…Acetone 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 was used as a solvent because of low boiling point (56 8C) so it could easily evaporate from electrode surface which is also advantage because extracted carotenoids are very sensitive to high temperature and oxygen. Furthermore, acetone was shown to be one of the best solvents for extraction of carotenoids [26] and is far less toxic then some other organic solvents.…”

“…CV experiments were performed at potential scan rates ranging between 10 and 1000 mV s À1 . 4 as electrolyte is based on literature data that demonstrated higher sensitivity using this electrolyte for the electrochemical determination of phenolic antioxidants [19,26]. The cyclic voltammograms of oxidation of b-carotene and astaxanthin consist of one broad peak for each compound, with maximum at 0.92 V and 1.16 V (3 M KCl), respectively, at scan rate of 0.1 V s À1 .…”

Monitoring and Control System used in Microalgae Crop

“…8. Lo anterior coincide con lo reportado por [25], [26], [27], quienes establecen que a longitudes de onda cortas (380-470nm) se puede inducir la acumulación de altas cantidades de astaxantina en H. pluvialis. Día En los resultados obtenidos, se ve la importancia de este tipo de prototipos ya que a la hora de realizar investigaciones en bioprocesos, estos permiten un monitoreo y control riguroso de las diferentes variables de proceso, garantizando la calidad en los bioprocesos y dando independencia al personal científico [6], además de permitir el aumento de la reproducibilidad de los procesos de producción rutinarios, logrando mayor eficacia para la investigación fisiológica causal-analítica, la verificación de los modelos de procesos, y el desarrollo de bioprocesos.…”

Simultaneous Determination of Piperacillin and Tazobactam in the Pharmaceutical Formulation Tazonam® by Derivative Spectrophotometry

“…This factor is used to amplify the analytical signal and the background noise in the same proportion [29]. It is necessary that a balance exists between signal amplification and the distorting effect on the spectral bands, because if the signal is amplified too much, it can distort, causing a misreading.…”