Hypoxis species (Hypoxidaceae) comprises twenty-nine species, but the research spotlight is on
Hypoxis hemerocalldea (
H. hemerocallidea). This study focused on the determination of phytochemical variations, total phenolic content, and antioxidant and antidiabetic potentials of five
Hypoxis species from South Africa with
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Hypoxis species (Hypoxidaceae) comprises twenty-nine species, but the research spotlight is on
Hypoxis hemerocalldea (
H. hemerocallidea). This study focused on the determination of phytochemical variations, total phenolic content, and antioxidant and antidiabetic potentials of five
Hypoxis species from South Africa with the aim of averting over-harvesting and extinction of
H. hemerocallidea. Standard protocols were used to determine six classes of phytochemicals, their variations, and antidiabetic and antioxidant potentials. Results obtained included variable phytochemicals (tannins, terpenoids, saponins, and deoxy sugar) content. All five
Hypoxis species tested positive for antioxidants with 0.2 mM 1,1-diphenyl-2-picrylhydrazyl solution. In terms of quantitative antioxidant activity,
Hypoxis obtusa displayed the best inhibition of 96.79% (IC
50 = 0.15 mg/mL) for 1,1-diphenyl-2-picrylhydrazyl and 96.93% (IC
50 = 0.04 mg/mL) for hydrogen peroxide, while
Hypoxis colchicifolia attained the lowest inhibition of 81.43% (IC
50 = 0.23 mg/mL) for 1,1-diphenyl-2-picrylhydrazyl and 81.25% (IC
50 = 0.05 mg/mL) for hydrogen peroxide. Furthermore,
Hypoxis obtusa and
Hypoxis hemerocallidea afforded the best antioxidant activity of 65.64% (IC
50 = 0.32 mg/mL) and 65.23% (IC
50 0.81 mg/mL) for the ferric reducing antioxidant power assay. The antidiabetic potentials were similar with
Hypoxis hemerocallidea and
Hypoxis obtusa equally inhibiting the two enzymes, with IC
50 of 0.21 mg/mL, 0.24 mg/mL, just like the standard acarbose with IC
50 of 0.20 mg/mL. The other three
Hypoxis extracts exhibited comparative antidiabetic inhibitory effects with IC
50 ranging from 0.34 to 0.55 mg/mL.
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