South African Helichrysum Research Articles

Methoxylated Flavonols and ent-Kaurane Diterpenes from the South African Helichrysum rutilans and Their Cosmetic Potential.

Chromatographic fractionation of a methanol extract of Helichrysum rutilans afforded seven known compounds. The isolated compounds were identified as 5,7,8-trihydroxy-3,6-dimethoxyflavone-8-O-2-methyl-2-butanoate (C-1), 5,7-dihydroxy-3,6,8-trimethoxyflavone (C-2), 5-hydroxy-3,6,7,8-tetramethoxyflavone (C-3), 5-hydroxy-3,6,7-trimethoxyflavone (C-4), ent-kaurenoic acid (C-5), ent-kauran-18-al (C-6), and 15-α-hydroxy-(-)-ent-kaur-16-en-19-oic acid (C-7). Compounds C-1-C-4 demonstrated high antioxidant capacities on ORAC hydroxyl radical (2.114 ± 4.01; 2.413 ± 6.20; 1.924 ± 16.40; 1.917 ± 3.91) × 106; ORAC peroxyl radical (3.523 ± 3.22; 2.935 ± 0.13; 2.431 ± 8.63; 2.814 ± 5.20) × 103 µMTE/g; and FRAP (1251.45 ± 4.18; 1402.62 ± 5.77) µMAAE/g, respectively. Moderate inhibitory activities against Fe2+-induced lipid peroxidation were observed for C-1-C-4 as IC50 values of 13.123 ± 0.34, 16.421 ± 0.92, 11.64 ± 1.72, 14.90 ± 0.06 µg/mL, respectively, while their respective anti-tyrosinase activities with IC50 values of 25.735 ± 9.62, 24.062 ± 0.61, 39.03 ± 13.12, 37.67 ± 0.98 µg/mL were also observed. All compounds demonstrated TEAC values within the range of 1105-1424 µMTE/g. The result is an indication that a methanol extract of H. rutilans might possibly be a good source of natural antioxidants against ailments caused by cellular oxidative stress and as inhibitors against skin depigmentation, as well as possible raw materials needed for slowing down perishable agricultural products. This is the first report on the phytochemical and biological evaluation of H. rutilans.

Reproductive, antioxidant, anti-inflammatory, antimicrobial, protective and antidiabetic activities of Helichrysum Mill. species

South African Helichrysum species are known for diverse medicinal use and treatment of different illnesses. Ethnopharmacological studies have revealed the potential use of Helichrysum plants in drug discovery. Although some of these species have been documented, there is still paucity of information on most species. This review seeks to provide a compilation of documented traditional uses, reproductive potential, antioxidant, anti-inflammatory, antimicrobial, protective and antidiabetic activities and other therapeutic properties of some Helichrysum species of South Africa. Information on Helichrysum cymosum, H. foetidum, H. odoratissimum, H. patulum and H. petiolare were collected from such scientific databases as Google scholar, Scifinder, PubMed, Elsevier, Scopus, Science direct in the form of journal articles, scientific reports, theses and books from the Library of the Cape Peninsula University of Technology. Our findings show that these species have historic values in traditional medicine through their diverse use for the management and treatment of such illnesses as cold, diabetes, headaches, digestive problems, sores and wounds, HIV, cancer etc. Additionally, the reported bioactive constituents isolated from these species have been shown to indicate several activities such as antimicrobial, antioxidant, antidiabetic, neuroprotection, reproductive potentials and others. Thus, the current review highlights the phytochemical and bioactive constituents as well as some of the pharmacological properties of the five selected Helichrysum species with a view to providing validation for their use in the pharmaceutical drug development process.

Volatolomics of Three South African Helichrysum Species Grown in Pot under Protected Environment.

Helichrysum decorum DC, Helichrysum lepidissimum S. Moore, and Helichrysum umbraculigerum are three species traditionally used in the South African medicine. The present work deals with the investigation of the spontaneous emission and the essential oils obtained from these plants cultivated in open field under uniform conditions. Fractions of the volatile organic compounds of the three species were rich in monoterpene hydrocarbons, representing more than 70% of the total composition. Pinene isomers were the most representative compounds: β-pinene in H. decorum (53.0%), and α-pinene in H. lepidissimum (67.9%) and H. umbraculigerum (54.8%). These latter two species evidenced an important amount of sesquiterpene hydrocarbons (SH) especially represented by γ-curcumene (H. lepidissimum) and α- and β-selinene (H. umbraculigerum). On the contrary, in the EOs, sesquiterpenes compounds prevailed, representing more than 64% of the identified fraction to reach more than 82 and 87% in H. umbraculigerum and H. lepidissimum, respectively. Although the chemical classes and their relative abundances were comparable among the three species, the individual compounds of EOs showed large differences. In fact, caryophyllene oxide (26.7%) and γ-curcumene (17.4%) were the main constituents in H. decorum, and H. lepidissimum respectively, while neo-intermedeol (11.2%) and viridiflorol (10.6%) characterized H. umbraculigerum.

An Andrographolide from Helichrysum caespitium (DC.) Sond. Ex Harv., (Asteraceae) and Its Antimicrobial, Antiquorum Sensing, and Antibiofilm Potentials.

Simple SummaryGonorrhea is a major public health concern globally and more than 800,000 new infections occur in the USA alone each year, according to the Centers for Disease Control (CDC). Health complications triggered by gonorrheal infection include HIV/AIDS and infertility, just to mention but a few. The Gram-negative gonococci bacteria resist known antibiotic treatments over the years, including penicillin, tetracycline, and fluoroquinolones, with only cephalosporins available for treatment currently. Resistance to the cephalosporins in many countries underlines the dire need for new antigonorrheal drugs. This study explored the potential of isolating an antigonorrheal compound from a nonpolar extract of Helichrysum caespititium. The 10-methyl-8-(propan-17-ylidene)naphthalen-9-yl)-11-vinyl-14-hydroxyfuran-16-one (CF6) isolated from the chloroform extract of the plant inhibited Neisseria gonorrhoeae with a MIC value of 60 µg/mL compared to ciprofloxacin with a MIC of 1 µg/mL. This compound indicates potential as a new antigonorrheal lead molecule.Helichrysum caespititium (DC.) Sond. Ex Harv., (Asteraceae) is a medicinal plant indigenous to South Africa. Its non-polar extracts exhibit significant antimicrobial and, in particular, antigonorrheal activity. This study aimed at isolating and purifying the active antigonorrheal compound from its chloroform extract and validating its inhibition potential on quorum sensing (QS) and biofilm formation of multi-drug resistant (MDR) pathogens. Phytochemical investigation of aerial parts of H. caespititium afforded a diterpene lactone (CF6). The effect of CF6 on violacein production and biofilm formation was studied using in vitro quantitative violacein inhibition (Chromobacterium violaceum) and biofilm formation (Streptococcus pyogenes, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Neisseria gonorrhoeae, and Pseudomonas aeruginosa). The structure of CF6 was characterized using FTIR, NMR, and UPLC-MS data accordingly, as 10-methyl-8-(propan-17-ylidene)naphthalen-9-yl)-11-vinyl-14-hydroxyfuran-16-one. The susceptibility testing of the pathogens against CF6 revealed Neisseria gonorrhoeae was noticeably susceptible with a MIC value of 60 µg/mL, while Streptococcus pyogenes and Staphylococcus aureus showed MIC of 125 µg/mL. All gram-negative pathogens, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa were inhibited at 250 µg/mL. CF6 also inhibited the production of violacein by 51.88% at 250 µg/mL and prevented cell attachment by 40.76–81.18%, with N. gonorrhoeae being highly prohibited from forming biofilm. In conclusion, 10-methyl-8-(propan-17-ylidene)naphthalen-9-yl)-11-vinyl-14-hydroxyfuran-16-one is the first of its kind to be isolated from the non-polar (chloroform) extract of South African Helichrysum caespititium with antigonorrheal, antimicrobial, antiquorum sensing, and antibiofilm properties. The compound may serve as a drug candidate against MDR pathogens.

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

Helichrysum genus was used in folk South African medicine to treat various human disorders. As a part of our on-going research addressing the exploitation of South African plants belonging to this genus, five species were investigated for their volatile and antimicrobial activities. The volatile organic compounds (VOCs) and the essential oils (EOs) were analysed by gas chromatography mass spectrometry (GC-MS). Microdilution was the method used for assessing both antimycotic and antibacterial activities, which was also tested by Kirby-Bauer agar disc diffusion. Total monoterpenes (TMs) dominated the VOCs of four species (H. trilineatum (70.6%), H. edwardsii (79.3%), H. cooperi (84.5%), and H. pandurifolium (57.0%)). H. cooperi and H. edwardsii EOs showed the predominance of TMs (68.2% and 84.5%, respectively), while H. pandurifolium and H. trilineatum EOs were characterized by the prevalence of TSs (86.5% and 43.6%, respectively). H. odoratissimum EO evidenced a similar amount of both TMs (49.5%) and TSs (46.4%). Microsporum canis was more sensitive to these EOs. The lowest minimum inhibitory concentration (MIC) was observed with H. pandurifolium and H. edwardsii EOs (0.25%). H. pandurifolium and H. trilineatum had a good effect on Staphylococcus aureus (MIC 5%). These findings open new perspectives for the exploitation of these natural compounds for application in cosmetics and pharmaceutics.

Volatiloma analyses of four South African Helichrysum spp. grown in Italy

The volatiloma of four Helichrysum species (H. anomalum, H reflexum, H. retortum and H. rugulosum) was analysed here for the first time by GC-MS for a chemotaxonomic contribution to this genus. Sesquiterpene hydrocarbons (SHs) prevailed in the aroma profile (VOCs) of H. reflexum, H. rugulosum and H. anomalum (74.7%, 93.6% and 41.6%, respectively), even though the main compounds were different (β-caryophyllene, α-humulene and α-copaene, respectively). The VOCs of H. retortum showed a high percentage of aliphatic hydrocarbons (NTs, 77.7%) mainly represented by octyl ether. The essential oil composition of each of H. rugulosum and H. retortum followed the same trend as VOCs related to the main class (SHs and NTs, respectively). In H. reflexum EO, the SHs were replaced by oxygenated sesquiterpenes (OS, 49.0%) with caryophyllene oxide as the main compound, while in H. anomalum the SHs were swapped in NTs (37.3%).

The effect of a South African Helichrysum sp. against important pathogenic mechanisms of Propionibacterium acnes

The effect of a South African Helichrysum sp. against important pathogenic mechanisms of Propionibacterium acnes

Genomic differences may drive speciation in South African Helichrysum odoratissimum

Genomic differences may drive speciation in South African Helichrysum odoratissimum

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

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), 1-benzoyl-3 (2S-hydroxyl-3-methylbut-3-enyl)-phloroglucinol (helinivene B, 2), 8-(2-methylpropanone)-3S,5,7-trihydroxyl-2,2-dimethoxychromane (helinivene C, 3), 1-(2-methylbutanone)-4-O-prenyl-phloroglucinol (4), 1-(2-methylpropanone)-4-O-prennyl-phloroglucinol (5), 1-(butanone)-3-prenyl-phloroglucinol (6), 1-(2-methylbutanone)-3-prenyl-phloroglucinol (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 Fe2+-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 exploitation of these natural phenolic compounds in applications such as in the natural cosmeceutical and pharmaceutical sectors.

Antimicrobial activity and in vitro cytotoxicity of selected South African Helichrysum species

The antimicrobial activity of 35 indigenous South African Helichrysum species was determined against six microorganisms. Seven of the 36 chloroform:methanol (1:1) extracts (leaf and stem extracts for all plants and an additional flower extract for H. rugulosum) exhibited minimum inhibitory concentration (MIC) values lower than 0.1 mg/ml against Bacillus cereus and/or Staphylococcus aureus. The in vitro cytotoxicity [against transformed human kidney epithelial (Graham) cells, MCF-7 breast adenocarcinoma and SF-268 glioblastoma cells] of these extracts was also determined at a concentration of 0.1 mg/ml using the sulforhodamine B (SRB) assay. For seven species less than 25% growth was observed for the Graham and MCF-7 cell lines at the test concentration.

South African Helichrysum species: A review of the traditional uses, biological activity and phytochemistry

Aims of the study In South Africa, the genus Helichrysum is widely used in traditional medicine. The uses are well documented although renaming of species and the resulting confusing taxonomic nomenclature may cause uncertainty as to which specific species was referred to in some reports. The aim of this paper is to present a collated and coherent overview of the documented traditional uses of Helichrysum species and to update the botanical identity of previously studied species. Materials and methods Databases (Scifinder, ISI Web of Knowledge) and several books were used to collect in information on South African Helichrysum species. Results The traditional uses, chemistry and biological activity of Helichrysum species have been summarized. It was attempted to give clarity as to exactly which species is refer to in the ethnobotanical literature. Conclusions Although a large number of ethnopharmacological uses have been documented and the chemistry of the genus has been studied extensively, only a few South African species have been investigated for their biological activity.

In vitro biological activity and essential oil composition of four indigenous South African Helichrysum species

Helichrysum species are used widely to treat various medical conditions. In this study, the anti-microbial, anti-oxidant (DPPH assay) and anti-inflammatory activity (5-lipoxygenase assay) of Helichrysum dasyanthum, Helichrysum felinum, Helichrysum excisum and Helichrysum petiolare were investigated. The essential oil compositions of these species were determined. The acetone and methanol extracts as well as the essential oils exhibited activity against Gram-positive bacteria, while both the methanol and acetone extracts of all four species were active in the anti-oxidant assay. The essential oils, on the other hand, displayed activity in the 5-lipoxygenase assay, which was used as an indication of anti-inflammatory activity. Two extracts exhibited promising activity in the anti-microbial assay, the acetone extract of Helichrysum dasyanthum with a MIC value of 15.63 μg/ml and the methanol extract of Helichrysum excisum with a MIC value of 62.5 μg/ml. The acetone extract of Helichrysum dasyanthum was the most active free radical scavenger in the DPPH assay (IC 50 of 9.53 μg/ml) while values for the anti-inflammatory activity of the essential oils ranged between 25 and 32 μg/ml. The essential oil compositions of three species ( Helichrysum dasyanthum, Helichrysum excisum and Helichrysum petiolare) were dominated by the presence of monoterpenes such as α-pinene, 1,8-cineole and p-cymene. In the oil of Helichrysum felinum, monoterpenes were largely absent. Its profile consisted of a variety of sesquiterpenes in low concentrations with β-caryophyllene dominating.

Antibacterial activity of South African Helichrysum species

Acetone extracts of Helichrysum callicomum, H. glomeratum, H. hypoleucum, H. odoratissimum, H. pilosellum and H. rugulosum were investigated for antibacterial activities against ten bacteria using the agar diffusion method. Epicuticular (shaken) and homogenized extracts of H. hypoleucum, H odoratissimum and H. rugulosum significantly inhibited the growth of Bacillus cereus, B. pumilus, B. subtilis, Micrococcus kristinae and Staphylococcus aureus (all Gram-positive bacteria) and Enterobacter cloacae (Gram-negative) at a concentration range of 0.01 to 1.0 mg/ml. In addition, the epicuticular extract of H. hypoleucum was active against Escherichia coli and Pseudomonas aeruginosa whereas the homogenized extract only had activity against P. aeruginosa, None of the other six extracts inhibited the growth of E. coli, Klebsiella pneumoniae, P. aeruginosa and Serratia marcescens, all Gram-negative bacteria. The extracts of H. glomeratum and H. pilosellum had no activity against any of the organisms tested. Shaken extracts proved to be more bioactive than homogenized extracts.

Twenty-one acylphloroglucinol derivatives and further constituents from south african Helichrysum species

The investigation of 27 South African Helichrysum species gave in addition to known compounds, 21 new acylphloroglucinol derivatives, five flavanoids, an unusual pyrone derivative, five diterpenes, a bicyclogermacrene and three cadinene derivatives, three guaianolides, a xanthanolide, a dimeric sesquiterpene lactone, an aliphatic lactone and seven glycerol angelate derivatives. The structures were elucidated by high field NMR techniques. The chemotaxonomic aspects are discussed in connection with previous investigations.

Phloroglucinol derivatives and other constituents from South African Helichrysum species

The investigation of 11 South African Helichrysum species afforded in addition to known compounds 26 further phloroglucinol derivatives, nine diterpenes, a derivative of isocomene and an α-pyrone derivative. The structures were elucidated by highfield NMR spectroscopy and a few chemical transformations. Furthermore the structures of several phloroglucinol derivatives were established by synthesis. The chemotaxonomy is discussed.

Weitere Phloroglucin- und α-Pyron-Derivate ausHelichrysum-Arten

The investigation of three South African HELICHRYSUM species afforded a tremetone derivative, where the acetyl group is methylated, four phloroglucin derivatives, two of them being chromones, four alpha-pyrone derivatives and a dihydro chalcone also derived from phloroglucine. The structures were elucidated by sepectroscopic methods.

Neue diterpene und neue dihydrochalkon-derivate sowie weitere inhaltsstoffe aus Helichrysum-arten

The investigation of 25 further Helichrysum species afforded in addition to known compounds a new diterpene, an oxo-geranyllinalol, a second one, most probably a cembrene derivative, and three dihydrochalkone derivatives. The distribution of the constituents in South African Helichrysum species is discussed briefly.

Cannabigerol-ähnliche verbindungen aus Helichrysum umbraculigerum

The investigation of a further South African Helichrysum species afforded eleven resorcinol derivatives, most of them closely related to cannabigerol and the corresponding acid, both also being present in the aerial parts of H. umbraculigerum. Furthermore a new geranyl chalcone is present. The structures are elucidated by spectroscopic methods and some chemical transformations. The occurrence of the cannabigerol-like compounds in a composite is surprising. Probably, some of these compounds are formed by the combination of three different biogenetic pathways.

Weitere phloroglucin-derivate aus Helichrysum-arten

Zusammenfassung The investigation of five further South African Helichrysum species afforded, in addition to known compounds, several new phloroglucinol derivatives, their structures being elucidated by spectroscopic methods and some chemical transformations. These results confirm the existence of several different chemical groups within this large genus.

Neue flavone und phloroglucin-derivate aus Helichrysum herbaceum und Helichrysum chrysargyrum

The investigation of two further South African Helichrysum species afforded five new flavones and six new phloroglucinol derivatives. The structures were elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic situation is discussed briefly.