Acylphloroglucinol Derivatives from the South African Helichrysum niveum and Their Biological Activities

Abstract

Phytochemical investigation of aerial parts of Helichrysum niveum (H. niveum) using different chromatographic methods including semi-preparative HPLC afforded three new (1-3) and six known (4-10) acylphloroglucinols alongside a known dialcohol triterpene (11). The structures of the isolated compounds were characterized accordingly as 1-benzoyl-3 (3-methylbut-2-enylacetate)-phloroglucinol (helinivene A, 1), (7), 1-butanone-3-(3-methylbut-2-enylacetate)-phloroglucinol (8), 1-(2-methylpropanone)-3-prenylphloroglucinol (9), caespitate (10), and 3β-24-dihydroxyterexer-14-ene (11). Excellent total antioxidant capacities were demonstrated by helinivenes A and B (1 and 2) when measured as oxygen radicals absorbance capacity (ORAC), ferric-ion reducing antioxidant power (FRAP), trolox equivalent absorbance capacity (TEAC) and including the inhibition of Fe 2+ -induced lipid peroxidation (IC50 = 5.12 ± 0.90; 3.55 ± 1.92) µg/mL, while anti-tyrosinase activity at IC50 = 35.63 ± 4.67 and 26.72 ± 5.05 µg/mL were also observed for 1 and 2, respectively. This is the first chemical and in vitro biological study on H. niveum. These findings underpin new perspectives for the OPEN ACCESSMolecules 2015, 20 17310 exploitation of these natural phenolic compounds in applications such as in the natural cosmeceutical and pharmaceutical sectors.

An assessment of phenolic profiles, fatty acid compositions, and biological activities of twoHelichrysumspecies:H. plicatumandH. chionophilum

“…The antioxidants inhibit or delay the oxidation caused by free radicals (Aguilera, Martin‐Cabrejas, & Mejia, ; Popoola et al, ). The radical scavenging activities of the plant extracts were determined by using the in vitro assays (ABTS and DPPH).…”

“…The members of the genus Helichyrsum are mostly used in traditional medicine for antimicrobial, antioxidant, and anti‐inflammatory therapies, as well as removing the kidney stone and supporting the wound healing process (Albayrak, Aksoy, Sağdiç, & Budak, ; Sala et al, ; Sezik et al, ). Furthermore, many studies have been carried out on the biological activities and phytochemicals of Helichrysum species, including the antioxidant, antimicrobial, anti‐inflammatory, cytotoxic, enzyme inhibitory activities related with the diabetes and Alzheimer diseases, as well as the anti‐aging properties (Aslan, Orhan, Orhan, Sezik, & Yesilada, ; Gonçalves et al, ; Gouveia‐Figueira et al, ; Ozcan & Acet, ; Popoola, Marnewick, Rautenbach, Iwuoha, & Hussein, , Tepe et al, ).…”

Composition, Antioxidant Potential, and Antimicrobial Activity of Helichrysum plicatum DC. Various Extracts

“…Compound Class/Name EE DCME ACNE pinellic acid [96], tianshic acid [97] + + (3,4,5,6,7-pentamethoxy-2-benzofuranyl)phenylmethanone [98] + PUFA 2 [99][100][101] + pinoresinol [102] + PUFA [99][100][101] + dihydro-5-(5,8-tetradecadienyl)-2(3H)-furanone [47] + PUFA [99][100][101] + + hexadecanal [103] + Unclassified 3 4-hydroxy-3,5-dimethyl-6-(1-methylethyl)-2H-pyran-2-one [30], 2-ethyl-6-methoxy-3,5-dimethyl-4H-pyran-4-one [28] + 3-prenyl-2,4,6-trihydroxyacetophenone [30], 4,6-dimethoxy-5-(2-methyl-1-propen-1-yl)-1,3-benzodioxole [80] + + helinivene A [104], piperitol [105], 1-[6-(acetyloxy)-2,3,4-trimethoxyphenyl]-3-phenyl-2-propen-1-one [106] + ent-kaurane derivative [73], eudesmane derivative [65] +…”

Volatilome Analyses and In Vitro Antimicrobial Activity of the Essential Oils from Five South African Helichrysum Species

“…Besides the species already mentioned by Lourens, new taxa were studied such as H. niveum Graham reported by Popoola [ 8 ]. Yadizi, in his turn, studied the anti-HIV screening of extracts from thirty-two South African Helichrysum spp., some of them (nineteen) never reported before [ 9 ].…”