ĐÁNH GIÁ THÀNH PHẦN POLYPHENOL VÀ HOẠT TÍNH ỨC CHẾ TYROSINASE CỦA CÁC DỊCH CHIẾT LÁ CALLISIA FRAGRANS

Tóm tắt

Callisia fragrans (C. fragrans) belongs to the family Commelinaceae and has wide applications in
the pharmaceutical field. The leaves were extracted by distillation in 40% methanol. The volatile extract (M)
was collected, while the extract remaining in the flask was fractionated with the obtained ethyl acetate
extract (Y) and the remaining extract after passing ethyl acetate (B). Total polyphenols (TPCs) of extracts in
(M), (Y) and (B) were determined spectrophotometrically using Folin Ciocalteu reagent, with Gallic acid
used as standard. The TPCs of (M), (Y) and (B) were determined as 4.7 ± 0.22 mg GAE/g, 17.91 ± 0.0031
mg GAE/g, 47.11 ± 0.22 mg GAE/g dry weight, respectively. By liquid chromatography – mass spectrum,
gallic acid and 1-O-(E)-caffeoyl-4,6-di-O-galloyl-β-D-glucopyranose were detected in (B). Furthermore,
tyrosinase inhibition was detected in extract (B) by tyrosinase inhibition assay due to the highest TPC
content, using kojic acid as standard due to its tyrosinase inhibitory ability. Relative inhibition of (B) was
17.29% and IC50 was 64.47 ± 0.06 µg/mL, equivalent to 2/3 the potency of kojic acid. Research has also
succeeded in creating microcapsules containing TPC. The study on C. fragrans contribute to the
pharmaceutical field.