Evaluation of anti-inflammatory activity and standardisation of hydro-methanol extract of underground tuber of Dioscorea alata

Figures & data

Figure 1. Demonstrates the effect of 70% hydro-methanol extract of D. alata areal tuber on (A) inhibition of nitric oxide; (B) down-regulation of TNF-α; *p  <0.05, **p < 0.01, and ***p < 0.001 compared with control (0 μg/mL).

Figure 2. Demonstrates the effect of 70% hydro-methanol extract of D. alata areal tuber on (A) Inhibition of cyclooxygenase activities; (B) down-regulation of prostaglandin E₂ level. ^NSp > 0.05, *p < 0.05, **p < 0.01, and ***p < 0.001 compared with control (0 μg/mL).

Figure 3. Demonstrates dose-dependent linear correlation of (A) TNF-α versus inhibition of nitric oxide; (B) TNF-α versus COX-2; (C) TNF-α versus PGE₂; (D) COX-2 versus PGE₂. Axes ‘x’ and ‘y’ denotes correlation points of respective parameters measured at different dose of D. alata extract (0–80 μg/mL). Where R² = coefficient of determination.

Figure 4. HPLC analysis of D. alata underground tuber extract. (1) gallic acid, (2) 4-hydroxy benzoic acid, (3) syringic acid, (4) p-coumaric acid, and (5) myricetin.

Figure 5. GC-MS analysis of D. alata underground tuber extract corresponding to Table 1. *Unidentified compound/repeat compound/column component.

Table 1. Phytochemicals identified in D. alata underground tuber extract by GC-MS analysis corresponding to Figure 5.

Sl no.	Compound name	Retention time (min)
1	Azulene	15.295
2	Phenol, 2,4-bis(1,1-dimethylethyl)	24.034
3	Pentadecanoic acid, methyl ester	30.915
4	Hexadecanoic acid, methyl ester	33.004
5	n-Hexadecanoic acid	34.274
6	Hexadecanoic acid, 15-methyl-, methyl ester	34.862
7	9,12-Octadecadienoic acid (Z,Z)-, methyl ester	36.257
8	Methyl stearate	36.720
9	9,12-Octadecadienoic acid (Z,Z)-	37.602
10	Indolizine, 3-methyl-	42.631
11	Bumetrizole	43.826
12	Cinnamyl cinnamate	45.634
13	Squalene	49.962