Antioxidant activity and total flavonoid content in variable phyto-stem cells extracts obtained by high-pressure homogenization method and assigned for use in biocosmetics

Antioxidant activity (AO) of with DPPH (µmol Trolox, TE) and total flavonoid content (TFC) with AlCl₃ (µg catechins CAE eq/mL) was determined for six commercially available callus culture extracts (CCE) from paper mulberry PM [Brussonetia kazinoki (family Moraceae)], grape stems GS [Vitis vinifera (Vitaceae)], magnolsi MA [Magnolia sieboldii (Magnoliaceae)], green tea GT [Camelia sinensis (Theaceae)], white ginseng WKG [Panax ginseng (Araliaceae)] and hydroponically cultivated ginseng HPG [Panax ginseng (Araliaceae)] and containing butylene glycol (3.0%), phenoxyethanol (0.9), ethylhexylglycerin (0.1) as preservatives. Highest TFC was presented by the WKG extracts (mean 2.8 µg CAE eq/mL). Not significantly different TFC in case of GT (2.2), HPG (2.1), MA (2.0) and decreased for the GS (1.9) and PM (1.5) was shown. Scavenging of DPPH radicals was highest for the GT extracts (mean 30.30 µmol TE) and not significantly different from WKG (29.99), HPG (29.80) and ME (29.71) but significantly lower than GS (28.82) and PM (27.66) extracts. These results for WKG and HPG extracts was quite parallel with previously reported value of the 29.10 µmol TE for 1.0% CCE of white P. ginseng roots. However, values from 5 to 20 mmol TE were reported for 0.001% CCE of Leontopodium alpinum (Asteraceae) flowers and 190 nmol TE for the 0.025% CCE from Euterpe oleracea (Arecaceae) fruits. Relationship between AO and TFC was not observed for studied CCE. However, high molecular antioxidant compounds with a high proton donor ability could indicate an increased steric inaccessibility to the stable nitrogen radical of DPPH thus contributes to inadequate results of this test [1]. Studied here CCE have DPPH based AO comparable with the 0.15 – 0.20% water solution of small molecule plant antioxidants as quinic (27.65 µmol TE), ascorbic (27.60), cinnamic (27.33), caffeic (28.84) or chlorogenic (28.60) acid.

References:

[1] Priori RL, Wu XL, Schaich K. J Agric Food Chem 2005; 53: 4290 – 4302