Replacement of expensive pure nutritive media with low cost commercial fertilizers for mass culture of freshwater algae, Chlorella vulgaris

• Published in: International journal of agriculture and biology 2011-01, Vol.13 (4), p.484-490
• Main Authors: Ashraf, M. (University of Veterinary and Animal Sciences, Lahore (Pakistan). Fisheries and Aquaculture Dept.), Javaid, M. (Fish Seed Hatchery, Faisalabad (Pakistan)), Rashid, T. (Fisheries Research and Training Inst., Lahore (Pakistan)), Ayub, M. (Punjab Fisheries Dept., Lahore (Pakistan)), Zafar, A. (Fisheries Research and Training Inst., Lahore (Pakistan)), Ali, S. (Fisheries Research and Training Inst., Lahore (Pakistan)), Naeem, M. (Bahauddin Zakariya Univ., Multan (Pakistan))
• Format: Article
• Language: English
• Subjects: AMMONIUM PHOSPHATE; AMMONIUM SULPHATE; CALCIUM FERTILIZERS; CELL CULTURE; CHLORELLA VULGARIS; CILIOPHORA; CONTAMINATION; CULTURE MEDIA; FERTILIZERS; GROWTH RATE; PHOSPHATE FERTILIZERS; POTASH FERTILIZERS; STARTER CULTURES; UREA
• ISSN: 1560-8530; 1814-9596

Chlorella sp., was isolated from wild water and purified on agar plates. Chlorella culture was further extended in Erlenmeyer's flasks on pure nutrient media (reagent grade chemicals) and then maximized in aspirators. Chlorella was then cultured on mass scale in polyethylene bags and 1000 L fiber glass tanks on commercial fertilizers (urea, nutri-calcium, ammonium sulfate, phosphorus plus (P+), potash-plus (K+), nitro-20 and di-ammonium phosphate (DAP) instead of pure nutrient media as practiced in flasks and aspirators. Various combinations of N, P and K were prepared empirically from aforementioned fertilizers and added to polythene bags and fiber glass tanks in fixed ratios for propagation of Chlorella vulgaris. Combined applications of urea, P+ and K+ (N:P:K: 16:4:6) produced the highest cell number (34.05x10(6) cells mL-1) and were far higher (p less than 0.05) than control group (8.5x10(6) cells mL-1). Duration of the log phase of Chlorella varied among containers. The polythene bags showed the best average (200%) and median (178%) growth rates of natural increase at exponential phase. Growth rate per day (244%), density (34.05x10(6) cell) and division's per day (2.9) were also highest in polythene bags. Fiberglass tanks were second in production and average algal growth, median growth, maximum growth rate per day, maximum cell density, divisions per day, generation time per day h-1 were 1.13 (113%), 1.19 (119%), 1.19 (119%), 23.15x10(6) cells mL-1, 1.63, 0.57 and 14.7, respectively. Chlorella in aspirators exhibited the poorest growth. The average and median growth rates were 34.95% and 39.93%, respectively. Growth rate per day was 57.64%, and maximum cell density did not exceed 8.5x10(6) cells mL-1 and divisions per day were only 0.504. Strong positive correlation was observed between number of cells and number of days. It was the highest in polythene bags (R2=0.9724) and the lowest in aspirators (R2=0.7539), while correlation values for fiberglass tanks fell in between these two extremes (R2=0.8355). Ciliates, major algae consumers were successfully controlled by the application of quinine sulfate @ 80 mg L-1 of water after 3 h of administration with no effect on algal cells.