Table 2.

Total phenol and flavonoids content and antioxidant potential of cyanobacterial cell-free extracts in terms of DPPH, ABTS, Deoxyribose protection and Fe⁺²-ion chelating activity

Organisms	Phenolics content		Antioxidant power (IC50) (mg ml−1 cell-free extract)
	Total phenol content (mg GAE g−1 fresh w)	Total flavonoid content (µg QE g−1 fresh w)	DPPH activity	ABTS activity	Deoxyribose protection activity	Fe+2-ion chelation activity
Anabaena doliolum	47.77 ± 3.4fg	106.93 ± 4.25j	2.64 ± 0.19b	0.39 ± 0.04efg	5.26 ± 0.11b	1.7 ± 0.36gh
Calothrix geitonos	22.80 ± 2.3j	91.0 ± 1.8kl	1.06 ± 0.18b	0.52 ± 0.06cd	3.94 ± 0.05c	3.5 ± 0.4e
Dichothrix sp.	35.23 ± 3.3hi	53.37 ± 3.81o	1.72 ± 0.24b	0.47 ± 0.06cde	2.96 ± 0.09e	3.2 ± 0.35e
Limnothrix obliqueacuminata	44.80 ± 3.9g	106.9 ± 7.3j	2.95 ± 0.2b	0.45 ± 0.07def	7.95 ± 0.09a	3.7 ± 0.45e
Microcheate tenera	45.57 ± 5.9g	88.37 ± 3.8l	4.28 ± 0.5b	0.37 ± 0.05efg	1.84 ± 0.08h	8.7 ± 0.36a
Oscillatoria acuta	290.23 ± 2.2a	634.0 ± 5.1a	2.63 ± 0.36b	0.97 ± 0.09a	3.64 ± 0.05d	1.4 ± 0.2hi
Nostoc ellipsosporum	39.03 ± 1.8h	115.03 ± 5.2i	8.91 ± 0.73a	0.45 ± 0.07def	2.59 ± 0.07f	4.7 ± 0.8d
Anabaena constricta	59.37 ± 4.0d	201.97 ± 3.3d	0.91 ± 0.04b	0.23 ± 0.07h	0.63 ± 0.04n	0.9 ± 0.22i
Synechocystis sp.	54.93 ± 2.65de	275.47 ± 2.8c	1.52 ± 0.06b	0.38 ± 0.08efg	0.86 ± 0.05lm	1.3 ± 0.2hi
Hapalosiphon fontinalis	33.43 ± 3.65hi	79.43 ± 2.9m	3.0 ± 0.19b	0.44 ± 0.04d–g	2.44 ± 0.12g	2.46 ± 0.36f
Mastigocladus laminosus	107.07 ± 4.04b	370.47 ± 2.7b	1.67 ± 0.11b	0.32 ± 0.04gh	1.35 ± 0.06j	2.42 ± 0.45fgh
Scytonema simplex	32.77 ± 2.65i	71.1 ± 2.8n	1.42 ± 0.19b	0.68 ± 0.09b	0.75 ± 0.13mn	4.5 ± 0.38d
Calothrix brevissima	31.47 ± 2.01i	95.13 ± 2.7k	2.24 ± 0.18b	0.34 ± 0.07fgh	0.92 ± 0.05l	2.4 ± 0.45fg
Westiellopsis prolifica	58.07 ± 4.51d	199.2 ± 3.13d	3.52 ± 0.26b	0.67 ± 0.04b	0.66 ± 0.05n	3.8 ± 0.8e
Cylindrospermum sp.	34.07 ± 4.27hi	157.9 ± 2.8g	1.27 ± 0.06b	0.32 ± 0.03gh	0.44 ± 0.08o	1.3 ± 0.26hi
Aulosira fertilissima	22.17 ± 1.81j	82.27 ± 2.05m	2.27 ± 0.19b	0.58 ± 0.04bc	1.78 ± 0.11h	7.8 ± 0.45b
Chroococcus sp.	52.07 ± 1.32ef	166.67 ± 1.96f	1.56 ± 0.09b	0.32 ± 0.06gh	0.32 ± 0.04o	2.4 ± 0.28fg
Limnothrix sp.	24.93 ± 2.4j	130.77 ± 1.7h	1.82 ± 0.09b	0.57 ± 0.05bc	0.81 ± 0.04lm	4.6 ± 0.49d
Lyngbya sp.	92.03 ± 1.59c	192.37 ± 2.0e	2.61 ± 0.13b	0.53 ± 0.07cd	1.15 ± 0.05k	2.6 ± 0.43c
Phormidium tenue	30.63 ± 1.04i	95.20 ± 2.05k	2.69 ± 0.21b	0.33 ± 0.05fgh	1.54 ± 0.05i	1.5 ± 0.31hi
SEM±	1.895	2.035	1.449	0.036	0.044	0.24
CD (p < 0.05)	5.415	5.817	4.142	0.104	0.126	0.70
CV (%)	5.7	2.1	99	13.5	3.6	12.60

Values represent average ± standard deviation for three replications; values in the same column with different superscripts are significantly different at p < 0.05

ND Not Detected, GAE gallic acid equivalents, QE Quercetin equivalents