Subcritical Water Extraction of Chlorella pyrenoidosa: Optimization through Response Surface Methodology

Table 2

Proximate, ultimate, and biochemical analysis of freshwater algae species.

Properties	Chlorella pyrenoidosa	Oedogonium sp.	Cladophora vagabunda
Proximate (wt.%)
Moisture	5.60	6.5	5.7
Ash	7.50	20.6	17.8
Biochemical (wt.%)
Organic content	86.90	72.9	76.5
Carbohydrate	22.80	41.0	44.4
Protein	62.70	22.5	26.8
Lipid	1.40	9.4	5.3
Ultimate (wt.%)
Carbon	44.53	36.6	37.5
Hydrogen	5.71	5.7	5.9
Oxygen	38.87	30.9	32.9
Nitrogen	9.80	4.8	6.5
Sulfur	1.09	0.4	1.8
HHV (MJ/kg)	18.06	15.8	16.4
Reference	This study	[15]	[15]

O (wt.%) = 100 – (C + H + N) (wt.%); HHV: higher heating value.