الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 175 |  |  |
| | | from | 175 | | |
Abstract
Low yields of S. platensis cultivated for commercial-scale required an intensive effort for the continuity of the culture with reducing the cost of required nutrients. Several experiments include the effect of different concentrations of nutrients on the growth of S. platensis have been carried out under laboratory conditions. The nutrients comprise sodium bicarbonate, sodium nitrate, sodium chloride, potassium sulfate, di-potassium mono-hydrogen phosphate, magnesium sulfate and calcium chloride. The results indicate that the maximum growth (dry weight mgL-1) values were recorded following the reduction in most nutrients of basal Zarrouk medium (SM) by 25%. The only exception was potassium sulfate since the maximum growth value was recorded at 50% less than its concentration in SM. On the other hand sodium chloride and magnesium sulfate application gave the maximum growth when both added in a similar amount to SM. The corresponding growth of the previous experiments was overall used to modify Zarrouk medium into modified one (YE). S. platensis was allowed to grow again in different modified media (urine medium, modified sewage medium, modified Zarrouk medium and Zarrouk medium as a control) for 21 days. Biochemical analysis of fat using GLC; amino acid by amino acid analyzer; water soluble vitamins and plant growth hormones using HPLC of S. platensis revealed that there are a significant increase in the different vitamins and both essential and nonessential amino acids in Spirulina grown in YE medium rather than in SM.