1Department of Biochemistry, Faculty of Basic Medical Science, Niger Delta University, Bayelsa State, Nigeria
2Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmacy, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria
*Corresponding Author E-mail: eboh.abraham@ndu.edu.ng
Online published on 28 May, 2025.
Absolute methanolic extract of the flower of Acmella caulirhiza was analysed for phytochemicals, antioxidants, antityrosinase activity in vitro and high-performance liquid chromatography (HPLC) analysis of phenolics. Phytochemical that were analysed were total flavonols, total anthocyanin, B-carotene and lycopene. Antioxidant and free radical assays carried out were total antioxidants (TAC), 1,1-diphenyl -2-picryl hydrazine radical scavenging DPPH, Ferric reducing antioxidant power (FRAP), super oxide radical scavenging, peroxynitrite scavenging, singlet oxygen scavenging and hypochlorous acid scavenging assay. Antityrosinase ability of Acmella caulirhiza was also evaluated. HPLC analysis of phenolics in the extract was carried out. The result shows a percentage yield of Acmella caulirhiza of 41.02%. Total antioxidant in Acmella caulirhiza was 103.65 ± 3.11 mg (ascorbic acid equivalent) AAE/g extract. The total amount of flavonol determined in Acmella caulirhiza was 466.13 ± 3.79 mg rutin equivalent per gram extract, total anthocyanin was 19.20 ± 1.3 mg cyanidin-3-glucoside equivalent/g and b-carotene and lycopene were 2.25 ± 0.17 mg/100ml carotene and 0.16 ± 0.04 mg/100 ml lycopene per gram extract respectively. The DPPH, FRAP, superoxide radical, peroxynitrite, singlet oxygen and hypochlorous acid scavenging presented as percentages shows higher scavenging ability of Acmella caulirhiza extract as compared to the standard antioxidants. The antityrosinase activity of Acmella caulirhiza extract showed moderate percentages of inhibition as depicted in the results but not as high as that of Kojic acid. There were many phenols detected from the flower extract of Acmella caulirhiza, phloretic acid, vanillic acid, gallic acid, cinnamic acid, ferulic acid, syringic acid, ellagic acid, piperic acid, luteolin, caffeic acid, sinapinic acid and chicoric acid. The present investigation revealed that absolute methanolic extract of Acmella caulirhiza extract has phytoconstituents, antioxidants, antiradicals and antityrosinase activity which can be applied in the cosmetics industry for hypopigmentation.
HPLC, Phenolics, Antioxidant, Antityrosinase properties, Acmella caulirhiza Extract
