Table 2 Reaction conditions for ultrasonic intensification on extraction of lipids from various microalgae

Chlorella vulgaris

10

CHCl₃-MeOH (1:1) (v/v)

Finely ground dried biomass with distilled water was subjected to microwave oven (Sharp R-15AT 1000 W; 2450 MHz: 150 s) and 5 min ultrasonication. The lipids were extracted with the solvent: biomass ratio of 2:1. The mixture was again ultrasonicated for 30 min

30

9.82

[64]

C. minutissima

10

n-Hexane

Dried biomass (100 mg) with 20 mL of n-hexane was subjected to ultrasonic bath and further centrifugated (4500 rpm for 10 min). Supernatant and cell debris were removed separately.

20

15.5

[60]

Thalassiosira fluviatilis

10

n-Hexane

20

40.3

[60]

T. pseudonana

10

n-Hexane

20

39.5

[60]

Chlorella sp.

20

Solvent free

700 mL of wet culture was ultrasonicated directly without dewatering using an ultrasonic system [ultrasonic processor, sonotrode, water cooling jacket for the flow cell (100 mL), recirculation tank for feed and processed sample storage and a centrifugal pump for sample circulation]

Continuous system

75

[65]