9. Physico-chemical properties of digested rotten potato (Solanum tuberosum) used as a production medium of spirulina (Spirulina platensis)

Abstract

The study was conducted to evaluate physico-chemical properties of digested rotten potato (Solanum tuberosum) used as a production medium of spirulina in sixteen days after twenty six days digestion. Three exclusive concentrations such as 20%, 40% and 60% of DRP (digested rotten potato) were used. Spirulina changed into inoculated in supernatant DRP for a period of 14 days. Light intensity (lux/m2 /s) was varied from 2725 ± 30, 2720 ± 32 and 2730 ± 34, respectively on first day to 2740 ± 30, 2780 ± 27 and 2694 ± 30, respectively on the last day in 20%, 40% and 60% DRPM. The pH values were 9.78 ± 0.07 to 9.95 ± 0.7 on 12th day in supernatant of 20% DRPM after which it turned into reduced to 9.77 ± 0 on ultimate day of experiment. Its change was observed 9.82 ± 0 to 9.90 ± 0 on 10th day of experiment of 40% DRPM. The electric conductivity was from 11.22 ± 0.10 to 14.74 ± 0.99, 11.54 ± 0.27 to 14.74 ± 0.99 and 11.23 ± 0.31 to 11.12 ± 0.47 on the 20%, 40% 60% DRPM, respectively. The salinity was 8.10 ± 0.70 in the 20% DRPM. The salinity was 5.17 ± 0 to 6.06 ± 0.26, 6.26 ± 0.17 to 7.60 ± 0.56, whilst spirulina cultured in supernatant of 60 % and 40% DRPM, respectively. The temperature and DO were also fluctuated with variation of DRPM concentration that affects the production of spirulina. The physico-chemical properties of 60 % DRPM was more suitable for spirulina culture.