Antioxidant Activity of Bakuchiol:  Experimental Evidences and Theoretical Treatments on the Possible Involvement of the Terpenoid Chain

Abstract

The protective activity of the plant-derived meroterpene, bakuchiol [1-(4-hydroxyphenyl)-3,7-dimethyl-3-vinyl-1,6-octadiene, 1], against oxidative damages to lipids and proteins has been investigated and rationalized based on the scavenging activity of 1 against various oxidizing radicals (Cl(3)CO(2)(*), linoleic acid peroxyl radicals, LOO(*), DPPH radicals, (*)OH, and glutathiyl radicals). The rate constants of the scavenging reactions, transients formed in these reactions, and their mechanistic pathways have been probed using optical pulse radiolysis technique. Besides 1, its methyl ether derivative 2 also could prevent lipid peroxidation in rat brain homogenate, indicating the probable participation of their terpenoid chains in scavenging LOO(*). This was further corroborated from the pulse radiolytic studies on the reaction between the glutathiyl radicals and the compounds 1 and 2 as well as two other congeners, 3 and 4, which showed transient absorptions at approximately 300 nm attributable to some C-centered allylic radicals. On the basis of the strong signals at approximately 300 nm with 1-3 as compared to compound 4, formation of the allylic radical adjacent to the trisubstituted olefin function in 1-3 was envisaged. This was confirmed by quantum chemical calculations of the relative energies of the probable radical species derivable from 2 using Hartree-Fock and density functional theory along with self-consistent reaction field model. In the case of 1, the allylic radical was found to be transformed into the phenoxyl radical at a later stage. All of these data revealed, for the first time, the importance of the terpenoid moiety of bakuchiol in controlling its antioxidant action via radical scavenging.

Production of bakuchiol by in vitro systems of Psoralea drupacea Bge

“…Because it is not inactivated by saliva or gastric juice (Prykhodko and Bondarenko 1979), bakuchiol has been used experimentally to treat pyogenic inflammation of the periodontal tissues in laboratory animals (Prykhodko et al 1984). In addition to its activity against micro-organisms and viruses, including plant viruses (Prykhodko et al 1982), bakuchiol also displays a range of other physiological properties including antiinflammatory, anti-oxidant and anti-tumour activity (Adhikari et al 2003;Backhouse et al 2001;Ryu et al 1992). These and other reported biological properties suggest that bakuchiol may ultimately be incorporated into new medicines, cosmetics and dental preparations.…”

EVALUATION OF THE ANTIOXIDANT CAPACITY OF Psoralea glandulosa L. (Fabaceae) EXTRACTS

“…Angelicin and psoralen that are found in a lower percentage in the leaves of the P. glandulosa have been reported to possess antibacterial and phototherapeutic activities (psoriasis, eczema, vitiligo, and cutaneous lymphoma) [36][37][38] . Moreover, bakuchiol is abundant in the leaves of P. glandulosa which has been reported to possess DNA polymerase inhibitory activity, antitumor, antifungal, cytotoxic and antioxidant activities [39][40][41][42] . The presence of these compounds contributed to the high scavenging power of the extracts of the leaves from culen.…”

Antimicrobial Activity of Extracts of Callus Cultures and Aseptic Plants of Psoralea Drupacea Bunge

“…³í ä³є íà ð³зí³ âèäè гðàìпîзèòèâíèх бàêòåð³é òà гðèб³â-äåðìàòîф³ò³â ó êîíöåíòðàö³ÿх â³ä 1 äî 10, ð³äшå äî 20 ìêг/ìë [5,4,13]. Êð³ì òîгî, âè-ÿâëÿє пðîòèâ³ðóñí³ [6] òà пðîòèпóхëèíí³ âëàñòèâîñò³, пðîòèзàпàëüíó òà àíòèîêñèäàíòíó àêòèâíîñò³ òîщî [8,7].…”