Foetidumins A-D, and other chemical constituents from Helichrysum foetidum (L.) Moench (Asteraceae) with antiparasite activity.

The phytochemical investigation of the MeOH and CH2Cl2-MeOH (1:1) extracts from the flowers and twigs of Helichrysumfoetidum (L.) Moench (Asteraceae), which showed antileishmanial and antiplasmodial activities during the preliminary screening, led to the isolation of four undescribed compounds, including two ent-beyer-15-ene-type diterpenoids, foetidumins A (1) and B (2), one flavonoid, foetidumin C (3) and one chalcopyrone, foetidumin D (4). Additionally, fourteen known compounds comprising, two ent-beyer-15-ene-type diterpenoids (5-6), six flavonoids (7-12), two steroids (13-14), three triterpenoids (15-17), and one glyceryl monostearate (18) were also isolated. The chemical structures of foetidumins A-D were fully elucidated by analyses of their spectroscopic data. The structure and the stereochemistry of foetidumin A (1) were confirmed by SC-XRD analyses. Among the tested compounds, foetidumin C (3), erythroxylol A (6), and kaempferol (7) displayed the highest antileishmanial potency with IC50 values of 13.0, 11.8, and 11.1 µM, respectively. Foetidumin C (3) had no cytotoxicity toward Vero cells with the selectivity index > 3.59. Meanwhile, extracts of flowers and twigs had higher activity against Plasmodium falciparum chloroquine-sensitive (Pf3D7) strain with IC50 values of 3.66 and 10.52 µg/mL, respectively.

Towards a modern approach to traditional use of Helichrysum italicum in dermatological conditions: In vivo testing supercritical extract on artificially irritated skin.

ETHNOPHARMACOLOGICAL RELEVANCE: Helichrysum italicum has been widely used in traditional medicine to treat allergies, colds, cough, skin, liver and gallbladder disorders, inflammation, infections, and sleeplessness. Furthermore, it possesses considerable wound healing and skin protective properties, documented by several in vivo studies performed on animals. However, there is a lack of experimental evidence supporting its potential as a topical agent tested by human clinical trials. AIM OF THE STUDY: The study aimed to investigate the skin protective activity of cotton gauze and polypropylene non-woven fabric, impregnated with H. italicum extract by the integrated supercritical CO2 extraction-supercritical solvent impregnation process. MATERIALS AND METHODS: The integrated process of supercritical CO2 extraction of H. italicum and the impregnation of cotton gauze and polypropylene non-woven fabric was performed under 350 bar and 40 °C with and without the addition of ethanol as a cosolvent. Impregnated textile materials were tested in vivo for their bioactivity on irritated human skin. Randomized in vivo studies performed involved assays of both safety and efficacy of the impregnated textiles. The effects were evaluated using the in vivo non-invasive biophysical measurements of the following skin parameters: electrical capacitance, transepidermal water loss, melanin index, erythema index, and skin pH. RESULTS: Both cotton gauze and polypropylene non-woven fabric were impregnated with H. italicum extracts under supercritical conditions with considerable values of the impregnation yield (1.97%-4.25%). The addition of ethanol as a cosolvent during the process caused significant changes in the incorporated extracts' impregnation yield and chemical profile. Both impregnated textile materials were safe, evaluated by their testing on the human skin with no cause of any irritation and redness. However, efficacy studies revealed that polypropylene non-woven fabric impregnated with H. italicum extract with ethanol as a cosolvent, possessed significantly greater potential for skin protection than the other investigated samples. CONCLUSIONS: The present study demonstrated the feasibility of the combined supercritical extraction and impregnation process in developing materials for topical application based on H. italicum extract. The results of in vivo studies performed on human volunteers confirmed the suitability of H. italicum active components to be a part of human skin protective preparations because of their ability to maintain the skin unimpaired. Traditionally claimed applications as a medicinal plant capable of regenerating skin have been scientifically proven, in addition to employing green technology in obtaining the impregnated materials with a broad spectrum of utilization.

Antioxidant and Toxic Activity of Helichrysum arenarium (L.) Moench and Helichrysum italicum (Roth) G. Don Essential Oils and Extracts.

Helichrysum arenarium (L.) Moench (sandy everlasting) is the only species from genus Helichrysum Mill that grows spontaneously in Lithuania. The chemical composition of the essential oils (EOs) from inflorescences and leaves of H. arenarium wild plants was analysed by GC-MS. Palmitic (≤23.8%), myristic (≤14.9%) and lauric (6.1%) acids, n-nonanal (10.4%), and trans-ß-caryophyllene (≤6.5%) were the major constituents in the EOs. For comparison, the main components in EO from flowers (commercial herb material) of H.italicum were γ-curcumene (21.5%), ß-selinene (13.6%), α-selinene (8.1%), ß-eudesmol (8.3%), and α-pinene (6.5%). Composition of H. arenarium methanolic extracts was investigated by HPLC-DAD-TOF. The main compounds were the following: luteolin-7-O-glucoside, naringenin and its glucoside, apigenin, chlorogenic acid, arenol, and arzanol. Antioxidant activity of EOs and extracts was tested by DPPH● and ABTS●+ assays. Sandy everlasting extracts exhibited significantly higher radical scavenging activities (for leaves 11.18 to 19.13 and for inflorescences 1.96 to 6.13 mmol/L TROLOX equivalent) compared to those of all tested EOs (0.25 to 0.46 mmol/L TROLOX equivalent). Antioxidant activity, assayed electrochemically by cyclic and square wave voltammetry correlated with total polyphenolic content in extracts and radical scavenging properties of EOs and extracts. The toxic activity of EOs of both Helichrysum species was evaluated using a brine shrimp (Artemia salina) bioassay. H. italicum inflorescence EO was found to be toxic (LC50 = 15.99 µg/mL) as well as that of H. arenarium (LC50 ≤ 23.42 µg/mL) oils.

Metabolite Profiling of Helichrysum italicum Derived Food Supplements by 1H-NMR-Based Metabolomics.

Helichrysum italicum is a medicinal plant from the Mediterranean area, widely used in traditional medicine for its anti-inflammatory, antibacterial and antioxidant properties and for its preventive effects on microcirculation diseases. Due to these properties, it finds large applications in cosmetic, food and pharmaceutical fields. Additionally, hydroalcoholic extracts and mother tinctures based on H. italicum represent products with a high commercial value, widely distributed not only in drug stores but also on on-line markets. The different extraction procedures used can greatly affect the fingerprints of the extracts, resulting in a different qualitative or quantitative profile of the chemical constituents responsible for biological activity. The aim of the present study was to characterize the composition of bioactive compounds present in water-ethanol and glycerol extracts of H. italicum derived food supplements. Metabolite profiles of the extracts were obtained by 1H NMR experiments and data were processed by multivariate statistical analysis to highlight differences in the extracts and to evidence the extracts with the highest concentrations of bioactive metabolites. In detail, this work highlights how derived food supplements of H. italicum obtained using ethanol-water mixtures ranging from 45% to 20% of ethanol represent the products with the highest amount of both primary (amino acids) and secondary metabolites including 3,4-dicaffeoylquinic acid (9), chlorogenic acid (10), 3,5-dicaffeoylquinic acid (11), and kaempferol 3-O-glucopyranoside (12). Moreover, it is evident that the use of an ethanol-water mixture 20:80 is the most suitable method to afford the highest number of phenolic compounds, while food-derived supplements obtained by glycerol extraction are characterized by a high amount of ß-glucose and α-glucose and a low content of phenolic compounds.

Linking the antimicrobial and anti-inflammatory effects of immortelle essential oil with its chemical composition - The interplay between the major and minor constituents.

Immortelle (Helichrysum italicum, Asteraceae) essential oil has been widely used in alternative medicine to accelerate wound healing, as well as in cosmetic products to stimulate skin regeneration and to reduce the appearance of wrinkles. It is also considered a natural and safe culinary spice that could also be applied in the food industry as a preservative in the future. The therapeutic efficacy of this oil changes with the natural variability of the composition. Herein we tested and mutually compared the antimicrobial and anti-inflammatory activities of four commercial immortelle oils differing in the relative amounts of marker compounds, i.e. neryl esters, α-pinene, γ- and ar-curcumenes, and ß-diketones. The anti-inflammatory effect of selected chromatographic fractions, enriched in the aforementioned constituents, was evaluated by studying toxicity toward rat peritoneal macrophages, their nitric oxide production, myeloperoxidase, and arginase activities. Subsequently, the compositional and activity data were subjected to a multivariate statistical treatment to reveal the possible correlation(s) between the percentage of essential-oil constituents and the observed activities. The obtained results imply that immortelle oil efficiency as an antimicrobial and/or anti-inflammatory agent is most plausibly a result of a synergistic action between its constituents, and/or, rather unexpectedly, the presence of some minor constituents.

Supercritical Carbon Dioxide Extraction of Four Medicinal Mediterranean Plants: Investigation of Chemical Composition and Antioxidant Activity.

With everyday advances in the field of pharmaceuticals, medicinal plants have high priority regarding the introduction of novel synthetic compounds by the usage of environmentally friendly extraction technologies. Herein, a supercritical CO2 extraction method was implemented in the analysis of four plants (chamomile, St. John's wort, yarrow, and curry plant) after which the non-targeted analysis of the chemical composition, phenolic content, and antioxidant activity was evaluated. The extraction yield was the highest for the chamomile (5%), while moderate yields were obtained for the other three plants. The chemical composition analyzed by gas chromatography-high-resolution mass spectrometry (GC-HRMS) and liquid chromatography-high-resolution mass spectrometry (LC-HRMS) demonstrated extraction of diverse compounds including terpenes and terpenoids, fatty acids, flavonoids and coumarins, functionalized phytosterols, and polyphenols. Voltammetry of microfilm immobilized on a glassy carbon electrode using square-wave voltammetry (SWV) was applied in the analysis of extracts. It was found that antioxidant activity obtained by SWV correlates well to 1,1-diphenyl-2-picrylhidrazine (DPPH) radical assay (R2 = 0.818) and ferric reducing antioxidant power (FRAP) assay (R2 = 0.640), but not to the total phenolic content (R2 = 0.092). Effective results were obtained in terms of activity showing the potential usage of supercritical CO2 extraction to acquire bioactive compounds of interest.

Evaluation of toxicological and antimicrobial activity of lavender and immortelle essential oils.

Lavender and immortelle essential oils (EOs) are widely used to treat a spectrum of human conditions. The aim of this study was to investigate cyto/genotoxic effects of lavender and immortelle EOs using plant cells (Allium cepa) and human lymphocytes, as well as their antimicrobial potential using nine strains of bacteria and fungi. Our results for lavender and immortelle EOs showed that the frequency of chromosome aberrations (CAs) was increased in comparison with controls. For both oils, increased frequency of apoptosis for all concentrations, as well as the frequency of necrosis (0.10/0.30 µl/ml for lavender/immortelle, respectively) was demonstrated. In human lymphocytes, differences for minute fragments between immortelle oil (0.10 µl/ml) and controls were observed. Increased frequency of apoptosis was detected for immortelle oil (0.20 µl/ml), while both oils (0.20; 0.30 µl/ml lavender, and immortelle at all concentrations) induced higher frequency of necrosis in comparison with controls. Lavender EO was effective against all tested Gram-positive and Gram-negative bacteria, while immortelle EO inhibited only Gram-positive bacteria. Both oils exhibited antifungal effect. Our results demonstrated that lavender and immortelle EOs showed cyto/genotoxic effects in both, plant and human cells, as well as antimicrobial properties. Further studies are needed to strengthen these findings.

Phenylpropanoids and flavonoid from Helichrysum petiolare Hilliard & B. L. Burtt.

The phytochemical analysis of a  methanolic extract from Helichrysum petiolare Hilliard & B. L. (Asteraceae) confirmed the content of phenylpropanoids and flavonoids. Five secondary metabolites were isolated using preparative HPLC, namely coumarin scopolin (1), 3-chlorogenic acid (2), caffeic acid-hexose derivative (3), dicaffeoylquinic acid (5), and the flavonoid isoquercitrin (4). These compounds were identified from this species for the first time. Only dicaffeoylquinic acid was able to inhibit Escherichia coli CCM 7929 at the concertation of 512 μg mL-1 in a screening of antibacterial activity.

In Vitro Evaluation of the Anti-Diabetic Potential of Aqueous Acetone Helichrysum petiolare Extract (AAHPE) with Molecular Docking Relevance in Diabetes Mellitus.

Diabetes mellitus (DM) is a chronic metabolic condition that can lead to significant complications and a high fatality rate worldwide. Efforts are ramping up to find and develop novel α-glucosidase and α-amylase inhibitors that are both effective and potentially safe. Traditional methodologies are being replaced with new techniques that are less complicated and less time demanding; yet, both the experimental and computational strategies are viable and complementary in drug discovery and development. As a result, this study was conducted to investigate the in vitro anti-diabetic potential of aqueous acetone Helichrysum petiolare and B.L Burtt extract (AAHPE) using a 2-NBDG, 2-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl) amino)-2-deoxy-d-glucose uptake assay. In addition, we performed molecular docking of the flavonoid constituents identified and quantified by liquid chromatography-mass spectrometry (LC-MS) from AAHPE with the potential to serve as effective and safe α-amylase and α-glucosidase inhibitors, which are important in drug discovery and development. The results showed that AAHPE is a potential inhibitor of both α-amylase and α-glucosidase, with IC50 values of 46.50 ± 6.17 (µg/mL) and 37.81 ± 5.15 (µg/mL), respectively. This is demonstrated by a significant increase in the glucose uptake activity percentage in a concentration-dependent manner compared to the control, with the highest AAHPE concentration of 75 µg/mL of glucose uptake activity being higher than metformin, a standard anti-diabetic drug, in the insulin-resistant HepG2 cell line. The molecular docking results displayed that the constituents strongly bind α-amylase and α-glucosidase while achieving better binding affinities that ranged from ΔG = -7.2 to -9.6 kcal/mol (compared with acarbose ΔG = -6.1 kcal/mol) for α-amylase, and ΔG = -7.3 to -9.0 kcal/mol (compared with acarbose ΔG = -6.3 kcal/mol) for α-glucosidase. This study revealed the potential use of the H. petiolare plant extract and its phytochemicals, which could be explored to develop potent and safe α-amylase and α-glucosidase inhibitors to treat postprandial glycemic levels in diabetic patients.

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.

Helichrysum araxinum Takht. ex Kirp. grown in Italy: volatiloma composition and in vitro antimicrobial activity.

In the present work the composition of biogenic volatile organic compounds (BVOCs) and the essential oil (EO) of Helichrysum araxinum Takht. ex Kirp. aerial parts, together with the antimicrobial activity, were investigated. The results showed the prevalence of sesquiterpene hydrocarbons in both spontaneous emissions as well as in the EO. The main compounds of BVOCs were γ-curcumene (10.7%), γ-muurolene (9.2%), and ß-selinene (8.5%). This latter constituent also showed a similar amount in the EO and represented the most abundant compounds together with α-selinene (8.0%). It is Interesting to note the same percentage of monoterpene hydrocarbons (MHs) in both the aroma profile and the EO (18.0%) with the same most abundant compounds: ß-pinene (6.3% in BVOCs vs. 5.1% in EO, respectively) and limonene (4.5% in VOCs vs. 4.9% in EO, respectively). With regard to the antimycotic activity, the EO showed to be inactive against the tested strains, while a moderate antibacterial activity was shown against Staphylococcus isolates.

Secondary metabolites of Helichrysum plicatum DC. subsp. plicatum flowers as strong carbonic anhydrase, cholinesterase and α-glycosidase inhibitors.

Helichrysum plicatum species are used in Turkish folk medicine as lithagogue, diuretic, and nephritic. Research on the methanol (MeOH) extract of flowers of H. plicatum DC. subsp. plicatum resulted in the isolation of eight known compounds (1-8). The chemical structures of the compounds were determined as ß-sitosterol (1), apigenin (2), nonacosanoic acid (3), astragalin (4), ß-sitosterol-3-O-ß-D-glucopyranoside (5), helichrysin A (6), helichrysin B (7), and isosalipurposide (8) by spectroscopic and chromatographic/spectrometric methods, including 1D and 2D nuclear magnetic resonance and liquid chromatography-tandem mass spectrometry. Nonacosanoic acid (3) was isolated for the first time from H. plicatum DC. subsp. plicatum. The MeOH extract and isolated compounds were evaluated for their in vitro human carbonic anhydrase I (hCAI) and II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase inhibitory activities. The IC50 values of H. plicatum DC. subsp. plicatum MeOH extract for hCAI, hCAII, AChE, BChE, and α-glycosidase were found to be 77.87, 52.90, 115.50, 117.46, and 81.53 mg/mL, respectively. The compounds showed IC50 values of 1.43-4.47, 1.40-4.32, 1.69-2.90, 1.09-3.89, and 1.61-3.80 µM against hCAI, hCAII, AChE, BChE, and α-glycosidase, respectively. In summary, H. plicatum DC. subsp. plicatum secondary metabolites demonstrated strong inhibitory effects especially against hCAI and hCAII, whereas the MeOH extract showed a weak inhibitory effect on all enzymes.

Assessing the cytotoxic/genotoxic activity and estrogenic/antiestrogenic potential of essential oils from seven aromatic plants.

Alternative therapies with new drugs are needed because the clinical efficacy of conventional chemotherapy is often reduced due to collateral effects. Many natural products of plant origin, including essential oils (EOs) have proved to be effective in prevention and therapy of several diseases such as bacterial infections, chronic diseases and cancer. In the present study, we investigated some biological activities of EOs extracted from seven plants: Rosmarinus officinalis, Salvia somalensis, Thymus vulgaris, Achillea millefolium, Helichrysum italicum, Pistacia lentiscus, Myrtus communis. In particular, we evaluated the cytotoxic and genotoxic activity using the cytochalasin B-blocked micronucleus assay (CBMN) in human peripheral lymphocytes, cytotoxicity in a human ovarian carcinoma cell line (A2780), and the estrogenic/antiestrogenic activity using a yeast strain expressing the human estrogen receptor alpha (ERα). Our results show that most EOs can have a strong cytotoxic and a slight/moderate genotoxic effect on human peripheral lymphocytes, and also a pronounced cytotoxic effect in A2780 cells. In addition, some EOs seem to have a marked antiestrogenic activity that could potentially perturb the estrogen-dependent tissues.

Pumpkin seeds, Centella asiatica, Boswellia, Helichrysum, acetate vitamin E, Melaleuca alternifolia and hyaluronic acid phytocomplex monotherapy effects in patients with chronic pelvic pain syndrome.

BACKGROUND: Proxelan® and antibiotics combined therapy was successfully previously used in the treatment of symptoms of patients with chronic prostatitis. Aim of the present study was to investigate the effects of Proxelan® monotherapy on pain symptoms of patients with chronic prostatitis (CP) or chronic pelvic pain syndrome (CPPS) in a prospective pilot study. METHODS: Thirty consecutive patients with CP/CPPS symptoms younger than 50, without urinary obstruction, total prostate-specific antigen (PSA) <4 ng/mL, negative microbiology testing on prostate fluid and urethral swab, naïve from other treatments during the previous three months were enrolled in a pilot study. IPSS and NIH-CPSI questionnaires were administered to all the patients. Patients could choose to be investigated regarding semen quality and IL6/IL8 seminal markers for inflammatory disease prior and after the therapy course. Proxelan® suppositories were prescribed for each patient for a month with a daily dosage of 1 suppository at bed-time. The primary endpoint of the study included at least a 30% reduction of pain symptoms because similar results can be obtained in each previously investigated placebo group. Effects on semen parameters such as leukocytospermia, spermatozoa concentration and motility, cytokine levels were considered as secondary endpoints. RESULTS: Subjective pain relief was obtained in all the patients with significant decrease of NIH-CPSI pain items (P=0.04). Urinary symptoms, investigated by IPSS questionnaire, decreased significantly (P=0.04) as well as quality of life items (P=0.04). Leukocytospermia was found in 5/15 patients available for further investigations. IL6 decreased by 11.55% one month after the treatment while sperm motility resulted increased by 17.3%. CONCLUSIONS: Proxelan® monotherapy may represents a promising valid alternative to combined treatment with antibiotics in patients with CP/CPPS symptoms although the results obtained should be investigated in randomized controlled trials.

Antifungal activity of oils macerates of North Sardinia plants against Candida species isolated from clinical patients with candidiasis.

Antibiotic resistance is one of the bigger problem of public health: the rise of multi-drug resistant organisms causes a challenge in the treatment of infective diseases. Anti-Candida resistance to conventional antifungal agents has increased in the last period. Our research was intended to evaluate antimicrobial activity of oil macerate (OM) of Helichrysum microphyllum Cambess. subsp. tyrrhenicum Bacch., Brullo & Giusso and OM of Hypericum perforatum subsp. angustifolium against several clinical strains. The study included 30 patients with candidiasis who had not received any antifungal treatment before they were enrolled. A collection of 30 clinical isolates belonging to 5 different species of Candida spp. was selected for this study. The data obtained showed an interesting activity of both Oil Macerate especially against C. krusei and C. parapsilosis. On the contrary, H. microphyllum Oil Macerate has had a better activity than the H.perforatum especially in relation to C. glabrata and C. krusei.

Cyclophosphamide-induced reproductive toxicity: Beneficial effects of Helichrysum odoratissimum (Asteraceae) in male Wistar rats.

OBJECTIVE: Cyclophosphamide (CP) is commonly used to treat some cancers, but its clinical efficacy is also linked with testicular toxicity. We investigated the effects of aqueous extract (AE) and methanolic extract (ME) of Helichrysum odoratissimum for reducing CP-induced reproductive toxicity in male rats. METHODS: In addition to a normal control (group 1), drugs or vehicles were administered orally to seven groups (n = 5) of rats that had already received 4-weeks of pre-treatment with CP (5 mg/[kg·d], per oral administration); group 2 received CP + distilled water (10 mL/[kg·d]); group 3 received CP + 5% tween 80 (10 mL/[kg·d]); group 4 received CP + clomiphene citrate (0.25 mg/[kg·d]); groups 5 and 6 received CP + AE (50 and 100 mg/[kg·d]) and groups 7 and 8 received CP + ME (50 and 100 mg/[kg·d]). Animals were sacrificed on day 15, and body and sexual organ weights, sperm characteristics, testosterone level and testicular histology were evaluated. RESULTS: The CP-treated group showed a significant reduction (P < 0.001) in the body and seminal vesicle weights, testosterone level, sperm count, sperm motility and sperm viability, but elevated (P < 0.001) sperm morphological abnormalities and testicular structure alterations, compared to the control group. Interestingly, these detrimental effects of CP were reversed by treatment with H. odoratissimum extracts. For instance, both extracts and all doses of H. odoratissimum significantly increased the sperm count (P < 0.001), sperm motility (AE, 50 mg/kg, P < 0.05; ME, 50 and 100 mg/kg, P < 0.05) and sperm viability (AE, 50 mg/kg, P < 0.001; ME, 50 and 100 mg/kg, P < 0.001) compared to the CP group. H. odoratissimum also improved plasmatic and intratesticular testosterone levels and prevented histological alterations of the testes. CONCLUSION: H. odoratissimum might be considered as an alternative drug to alleviate/prevent reproductive damage in cancer patients receiving CP chemotherapy.

In Vitro Anticollagenase and Antielastase Activities of Essential Oil of Helichrysum italicum subsp. italicum (Roth) G. Don.

The chemical composition of the essential oil of flowering aerial parts of Helichrysum italicum subsp. italicum cultivated in central Italy, Marche region, was analyzed by means of gas chromatography-mass spectrometry. Seventy-eight components, accounting for 98.71% of the whole essential oil composition, were identified and quantified. Neryl acetate showed the largest relative abundance in the composition, accounting for 15.75% of the oil, followed by α-pinene (8.21%); 4,6,9-trimethyl-8-decene-3,5-dione, (Italidione I), (7.34%); ar-curcumene and ß-selinene (5.37%); γ-curcumene (4.83%); nerol (4.75%); α-selinene (4.68%); limonene (4.55%); linalool (4.42%), and 2,4,6,9-tetramethyl-8-decene-3,5-dione (Italidione II), (4.26%). The oil inhibited in vitro collagenase and elastase activities, with IC50 values of 36.99 ± 1.52 and 135.43 ± 6.32 µg/mL, respectively. Neryl acetate, nerol, and linalool, distinctive compounds of the oil obtained from this plant, tested alone or in mixture, at the same percentages shown in the essential oil, exhibited no activity against the two enzymes. On the contrary, α-pinene and limonene, tested alone and in mixture, showed inhibitory activity on both collagenase and elastase.

HPLC-Based Activity Profiling for Antiprotozoal Compounds in the Endemic Iranian Medicinal Plant Helichrysum oocephalum.

In a screening of Iranian plants for antiprotozoal activity a dichlomethane extract from the aerial parts of Helichrysum oocephalum showed in vitro antiprotozoal activity against Plasmodium falciparum and Leishmania donovani, with IC50 values of 4.01 ± 0.50 and 5.08 ± 0.07 µg/mL, respectively. The activity in the extract was tracked by HPLC-based activity profiling, and subsequent targeted preparative isolation afforded 24 compounds, including pyrones 22-24, phloroglucinol derivatives 12-19, and compounds containing both structural motifs (1-11, 20, and 21). Of these, 15 compounds were new natural products. The in vitro antiprotozoal activity of isolates was determined. Compound 3 showed good potency and selectivity in vitro against L. donovani (IC50 1.79 ± 0.17 µM; SI 53).

Synergistic potential of Juniperus communis and Helichrysum italicum essential oils against nontuberculous mycobacteria.

OBJECTIVE: The present study evaluated the possible synergistic antimycobacterial interactions of Juniperus communis and Helichrysum italicum essential oils (EO). METHODS: Antimycobacterial potential was tested against Mycobacterium avium and Mycobacterium intracellulare using broth and water dilution method and checkerboard synergy method. Antiadhesion and antibiofilm effect of EOs was evaluated on biotic (HeLa cells) and abiotic surface (polystyrene). To evaluate the possible mechanisms of action, cellular leakage of proteins and DNA was tested and structural changes were visualized with a transmission electron microscope. RESULTS: MIC, minimum bactericidal concentration (MBC) and minimal effective concentration (MEC) were 1.6 mg ml-1 for J. communis EO and 3.2 mg ml-1 for H. italicum EO against both mycobacteria. All combinations of EOs in checkerboard synergy method produced fractional inhibitory concentration index values ranging from 0.501 to 1.5, corresponding to synergistic, additive or indifferent effects. Mycobacterium avium showed a greater tendency to create biofilm but these EOs at subinhibitory concentrations (sMIC) effectively blocked the adhesion and the establishment of biofilm. The exposure of both mycobacteria to MICs and sMICs lead to significant morphological changes: acquired a swollen form, ghost-like cell, disorganized cytoplasm detached from the cell wall. OD value of supernatant for both mycobacteria exposed to EOs have confirmed that there is a leakage of cellular material. CONCLUSION: The leakage of the cellular material is noticeably higher in sMIC, which is probably due to cell wall damage. sMIC of both EOs have an additive or synergistic effect, reducing MICs, limiting adhesion and preventing the formation of biofilms.

Pyrone derivatives from Helichrysum italicum.

Chemical investigation of aerial parts of Helichrysum italicum yielded two new pyrone derivatives (1 and 2) along with ten known compounds. The structures of the new compounds were established by 1D and 2D NMR spectra as well as by HRESIMS data. Compound 1 represented a rare dimer of substituted α- and γ-pyrone units. DFT-NMR and TDDFT-ECD calculations were carried out to determine the absolute configuration of 1 but failed, representing the limitation of TDDFT-ECD calculation for the configurational assignment. All compounds were measured for their antibacterial and cytotoxic activity but proved to be inactive.