Pharmacological activities of brown seaweed Sargassum wightii (Family Sargassaceae) using different in vitro models

Figures & data

Table 1. Type and integral values of protons obtained from the ¹H-NMR of the EM and CHCl₃ fractions of seaweed S. wightii.

		Integral values of protons
^aType of protons	Chemical shift (δ)	EM	CHCl3
Saturated hydrocarbons	0.5–2	578.9	687.22
CH2=CH-CH3/RC(=O)CH3/RCH2C(=O)OR1/Ar-CH3	2–2.5	100.94	65.51
-OCH3/RCH2-X/RCH2OH	2.5–3.5	43.94	59.62
Anomeric (due to polysaccharides)	3.5–4.5	106.09	114.39
RCH=CHR1/RCH2C(=O)OCH3	4.5–6.0	74.11	79.62
Ar-H	6.5–8.5	2.93	0.19

^aThe protons at the defined regions of the ¹H-NMR spectra were integrated to get the number of protons in specific regions.

Table 2. Phenolic content, antioxidant, anti-inflammatory, antidiabetic, and ACE inhibitory activities of the EM and CHCl₃ fractions of the seaweed S. wightii.

	Standard	EM	CHCl3
^wTotal phenolic content	—	2.51 ± 0.57^a	2.04 ± 0.56^b
Antioxidant activities
^xDPPH·radical scavenging	0.03 ± 0.01^a	0.32 ± 0.01^b	0.37 ± 0.01^c
^xABTS^+. radical scavenging	0.07 ± 0.01^a	0.82 ± 0.07^b	1.35 ± 0.09^c
^xFe^2+ ion chelating	0.03 ± 0.01^a	0.52 ± 0.07^b	1.45 ± 0.09^c
^xScavenging of H2O2	0.08 ± 0.01^a	0.19 ± 0.02^b	0.36 ± 0.05^c
^yLipid peroxidation inhibitory	—	51.08 ± 0.83^a	53.72 ± 0.37^b
Anti-inflammatory activities
^xCOX-1 inhibitory activity	0.83 ± 0.03^a	0.05 ± 0.01^b	0.17 ± 0.04^c
^xCOX-2 inhibitory activity	0.86 ± 0.07^a	0.03 ± 0.01^b	0.09 ± 0.01^b
^x5-LOX inhibitory activity	0.86 ± 0.09^a	0.03 ± 0.01^b	0.05 ± 0.01^b
Antidiabetic activities
^xα-Amylase inhibitory activity	0.403 ± 0.01^a	0.080 ± 00.00^b	0.140 ± 0.01^c
^xα-Glucosidase inhibitory activity	0.210 ± 0.01^a	0.005 ± 0.00^b	0.069 ± 00.00^c
^xDPP-4 inhibitiory activity	0.007 ± 0.00^a	0.013 ± 0.00^b	0.028 ± 0.01^c
Antihypertensive activities
^xACE-1 inhibitory activity	0.077 ± 0.01^a	0.11 ± 0.01^b	0.084 ± 0.01^c

EM: ethyl acetate-methanol and CHCl₃:chloroform solvent fractions.

The samples were analyzed in triplicate (n = 3) and expressed as mean ± standard deviation. Means followed by the different superscripts (a–c) within the same row indicate significant difference (p < 0.05).

^wTotal phenolic contents were determined at 20 mg/mL, and presented as mg of gallic acid equivalence (GAE)/g.

^xThe IC₅₀ values were expressed as mg/mL.

^yLipid peroxidation inhibitory (TBARS assay) was expressed as mM MDAEQ/kg.

Figure 1. FT-IR spectra of A: EM and B: CHCl₃ solvent fractions of S. wightii. The functional groups representing the distinct regions of the IR spectra were illustrated as (1) OH_ν of phenols and/or alcohols or N-H_ν of amide groups, (2) >C=O_ν of aldehydes or saturated aliphatic groups, (3) C-C_ν of the aryl ring framework, and (4) C=C_ν of olefinic groups. Stretching vibration has been indicated by “ν” as subscript to the functional group.

Figure 2a. ¹H-NMR spectra of EM.

Figure 2b. CHCl₃ solvent fractions of S. wightii. The protons at the defined regions of the ¹H-NMR spectra were integrated to get the number of protons in specific regions.

Figure 2c. The stacked plot representing the ¹³C-NMR spectra of EM and CHCl₃ fractions of S. wightii. The functional groups representing the distinct regions of the ¹H- and ¹³C-NMR spectra were labeled.

Figure 3. Loading plot diagram (various components viz., PC-1 and PC-2 in rotated space) of antioxidant activities vis-à-vis anti-inflammatory, anti-diabetic and anti-hypertensive activities of different solvent fractions from S. wightii.