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R. Abdulla et al.
Fig. 1 Cultivation of Chlorella sp.
1011, 1000 series) for every 3 days, up to 30 days (Leupold et al. 2013; Tuantet et al.
2014).
Microalgae cells were harvested during their mid-exponential phase. The microalgae cultures were centrifuged at 4500 × g for 10 min. The resulting supernatant was
discarded and the pellet was washed with distilled water (dH 2 O) in order to discard
the impurities. The centrifugation process was repeated under the same condition.
The concentrated pellet was transferred to a petri dish and dried in an oven at 60 °C
for 24 h. The dried microalgae were homogenized by using a blender and stored at
room temperature (Harun et al. 2010; Harun and Danquah 2011b).
Figure 1.2 shows the growth curve of microalgae cells for 30 days. According to
the growth curve, the microalgae cells showed positive growth pattern from day 0
up to day 27. From day 0 to day 6, the number of microalgae cells were increased
moderately as the absorbance value was increased from 0.013 ± 0.002 to 0.100 ±
0.005. From day 6 to day 15, the microalgae cells showed a significant growth trend
as observed in Fig. 1.2 and the absorbance increased from 0.100 ± 0.005 to 0.608 ±
0.060. From day 15 to day 27, the growth rate started to decrease with the increase
of absorbance value of only 0.143, to 0.751 ± 0.094 at day 27. From day 27 to day
30, the number of microalgae cells had started to decline. The absorbance value at
day 30 was 0.690 ± 0.077, which was 0.061 lesser than that at day 27.
R. Abdulla et al.
Fig. 1 Cultivation of Chlorella sp.
1011, 1000 series) for every 3 days, up to 30 days (Leupold et al. 2013; Tuantet et al.
2014).
Microalgae cells were harvested during their mid-exponential phase. The microalgae cultures were centrifuged at 4500 × g for 10 min. The resulting supernatant was
discarded and the pellet was washed with distilled water (dH 2 O) in order to discard
the impurities. The centrifugation process was repeated under the same condition.
The concentrated pellet was transferred to a petri dish and dried in an oven at 60 °C
for 24 h. The dried microalgae were homogenized by using a blender and stored at
room temperature (Harun et al. 2010; Harun and Danquah 2011b).
Figure 1.2 shows the growth curve of microalgae cells for 30 days. According to
the growth curve, the microalgae cells showed positive growth pattern from day 0
up to day 27. From day 0 to day 6, the number of microalgae cells were increased
moderately as the absorbance value was increased from 0.013 ± 0.002 to 0.100 ±
0.005. From day 6 to day 15, the microalgae cells showed a significant growth trend
as observed in Fig. 1.2 and the absorbance increased from 0.100 ± 0.005 to 0.608 ±
0.060. From day 15 to day 27, the growth rate started to decrease with the increase
of absorbance value of only 0.143, to 0.751 ± 0.094 at day 27. From day 27 to day
30, the number of microalgae cells had started to decline. The absorbance value at
day 30 was 0.690 ± 0.077, which was 0.061 lesser than that at day 27.