Table 1.
Some Sesquiterpenoids that haveanticholinesterase inhibitory activity.
| Name of Plant | Part Used (Family) | Solvent/Method Used for Extraction | Extract/Volatile oil/Phytoconstituents | Acetyl-Cholinesterase Inhibitory/Anti-Alzheimer Potential | Ref. |
|---|---|---|---|---|---|
| Lycopodiastrum casuarinoides | Whole plants (Lycopodiaceae) |
EtOH (75%) | 7, 9 -diene -1,4 -epoxy-2 -hydroxy -10 -carboxylic acid [13] | Potential inhibitory effects against AChE and BuChE with an IC50 = 9 ± 1 μM and 9 ± 1 μM respectively | [98] |
| Lycium europaeum Linn. | Roots and leaves (Solanaceae) |
Ethanol | Ethanolic fraction | Ethanolic fraction of leaves (at 15 mg/kg) exhibited effect on learning and memory of experimental animals with IC50 = 76 ± 2 mg/mL | [99] |
| Aquilaria or Gyrinops | Roots and resinous heartwood (Thymelaeaceae) |
95% EtOH | 2-oxoguaia-1(10),3,5,7(11), 8-pentaen-12,8-olide (14) (Sesquiterpenoids) 4β,7α-H-eremophil-9(10)-ene-12,13-diol (15) (Eremophilane- sesquiterpenoid) 4β,5α,7α,8α-H-3β-hydroxy-1(10)-ene-8,12-epoxy-guaia-12-one (16) (−)Gweicurculactone (17) (Guaiane-sesquiterpenoid) |
The isolated compounds showed the AChE inhibitory activity at 50 μg/mL ((IC50) IC50 (14) = 226 μM IC50 (15) = 140 μM IC50 (16) = 141 μM IC50 (17) = 202 μM Tacrine ( + ve control) = 65 ± 1 μg/mL |
[100] |
| Valeriana jatamansi Jones | Roots and rhizomes (Valerianaceae) | EtOH (95%) | Valeriananoids D (18) Valeriananoids E (19) |
At the conc. of 50 μM showed AChE inhibition potential activity | [101] |
| Aquilaria sinensis (Lour.) | (Thymelaeaceae) | EtOH (95%) | 3-oxo-7-hydroxyl holosericin A (20) 1,5;8,12-diepoxy-guaia-12-one (21) 8αβ)-octahydro-7-[1-(hydroxymethyl (22) 7α H- ethenyl]-1,8α-dimethyl naphthalen-4α(2H)-o (23) Neopetasane (24) |
Moderate inhibitory activities against Acetylcholinesterase (AChE) at 50 µg/mL, IC50 (20) = 75 μM IC50 (21) = 53 μM IC50 (22) = 71 μM IC50 (23) = 87 μM IC50 (24) = 324 μM |
[102] |
| Rhodomyrtus tomentosa | leaves and stems (Myrtaceae) |
Petroleum ether (PE) extract | (Triketone-sesquiterpene meroterpenoids) | AChE inhibition rate is 81% at 500 μg/mL) | [103] |
| Nelumbo nucifera | Seeds (Nelumbonaceae) | essential oil (EO), crude extract, and subsequent fractions | Essential oil mainly comprised of oxygenated mono and sesquiterpenes | The ethyl acetate fraction and EO caused significant inhibition of acetyl-cholinesterase and butyryl-cholinesterase with IC50 = 70 ± 1, 64 ± 1 and 75 ± 0.3, 58 ± 0.2, respectively in a dose-dependent manner. EO was found to be non-competitive inhibitor of AChE. |
[104] |
| Asteriscus maritimus (Linn.) Less | Different parts of the plant (Asteraceae) | Hydrodistillation | Oxygenated sesquiterpenes of Essential oil | Among the essential oils obtained from flowers, leaves, and stems, the flower oil was found to exhibit the highest anti-acetylcholinesterase activity (IC50 = 95 µg/mL) | [105] |
| Myrciaria floribunda (H. West ex Willd.) | Essential oil of fruit peel (Myrtaceae) |
Hydrodistillation method |
Essential oil with different sesquiterpenes | Essential oil exhibited the AChE inhibitory potential with IC50 = (0.08 μg/mL and 23 μg/mL). Neostigmine (as the standard used) had an IC50 of 23 μg/mL and 6 μg/mL). |
[97] |
|
Nigrospora oryzae and Irpex lacteus (Fungus on plant ) |
Culture | Acetone | Tremulanesesquiterpenes | AChE inhibitory potential concentration of 50 μM. | [106] |
| Curry Leaf |
Murraya koenigii (Rutaceae) |
Hexane and methanol | Essential oil | Inhibitory activities of active compounds of curry leaves against β-secretase were found and hence reported to be helpful in preventing dementia (AD). methanolic extract (70%) also showed weak inhibitory activity at 500 μg/mL against AChE |
[107] |
| Teucrium persicum Boiss | Aerial parts (Labiatae) | Methanol (85%) | Guaiasistanol (25) (Guaianesesquiterpenoid) |
Moderate inhibition of AChE (28%) by the isolated compound. | [108] |
| Daphne holosericea (Diels) Hamaya | Dry stems (Thymelaeaceae) |
Extracted with EtOH (95%) under reflux three times | Holosericin B (26) (Guaiane Sesquiterpenoids) |
The isolated compound showed a moderateAChE Inhibitory Activity with 31% inhibition. | [109] |
| Aquilaria sinensis (Lour.) Gilg | Heartwood (Thymelaeaceae) | Refluxed with Ethanol (95%) | Extract | EtOAc extract showed weak AChE inhibitory activity | [110] |
| Homalomena sagittifolia | Rhizomes (Araceae) |
Macerated with aqueous methanol | 1α,4β,7β- eudesmanetriol (27) 1β, 4β, 7β-eudesmanetriol (28) (Sesquiterpenoids) |
Inhibition of acetylcholinesterase with IC50 (I) = 26 ± 4; (II) = 250 ± 8 μM | [111] |
| Valeriana officinalis | Roots (Caprifoliaceae) |
EtOH (95%) | Spatulenol (29) (Sesquiterpenoids) |
AChE was inhibited at 100 mM (49%) | [112] |
|
Marsupella alpine (Chinese liverwort) |
Whole plants (Gymnomitriaceae) |
95% EtOH (95%) | Marsupellin A (30) Marsupellin B (31) (ent-Longipinane-Type Sesquiterpenoids) |
A bioautographic TLC assayforAChE inhibition was performed and compound showed moderate inhibition at 5 μM (28% and 26% respectively). | [113] |
| Santalum album | Heartwood (Santalaceae) |
Steam distillation | α-santalol (32), Sandalwood oil (rich in sesquiterpenoid alcohols) the major constituent of the oil |
TLC-bioautographic and colorimetric methods are used. Essential oil is found to be a potent inhibitor of tyrosinase IC50 = 171 µg/mL) and cholinesterase IC50 = 5–58 µg/mL. For α-santalol, AChE Inhibition Zone (mm2) and BChE Inhibition Zone (mm2) were reported as 326 ± 19 and 425 ± 27 respectively. |
[114] |
| Hedychium gardnerianum Sheppard ex Ker-Gawl | Leaf essential oil (Zingiberaceae) | Hydrodistillation | Sesquiterpene hydrocarbons (47.8 to 52.7%) and oxygenated sesquiterpenes (15.2 to 16.3%) are main constituents of oil | Microplate Assay was performed and the strongest inhibition against AChE was displayed by the sample collected from Furnas (FU) at IC50 = 1 mg/mL. | [115] |