Comparative chemical composition and variability of biological activity of methanolic extracts from Hypericum perforatum L

Extracts against Human Melanoma Cells from Different Stages of Cancer Progression, Cultured under Normoxia and Hypoxia

Oxidative stress and the hypoxic microenvironment play a key role in the progression of human melanoma, one of the most aggressive skin cancers. The aim of our study was to evaluate the effect of Hypericum perforatum extracts of different origins (both commercially available (HpEx2) and laboratory-prepared from wild grown (HpEx12) and in vitro cultured (HpEx13) plants) and hyperforin salt on WM115 primary and WM266-4 lymph node metastatic human melanoma cells cultured under normoxic and hypoxic conditions. The polyphenol content, radical scavenging activity, and hyperforin concentration were determined in the extracts, while cell viability, apoptosis, ROS production, and expression of NRF2 and HO-1, important oxidative stress-related factors, were analyzed after 24 h of cell stimulation with HpExs and hyperforin salt. We found that cytotoxic, pro-apoptotic and antioxidant effects depend on the extract composition, the stage of melanoma progression, and the oxygen level. Hyperforin salt showed lower activity than H. perforatum extracts. Our study for the first time showed that the anticancer activity of H. perforatum extracts differs in normoxia and hypoxia. Importantly, the composition of extracts of various origins, including in vitro cultured, resulting in their unique properties, may be important in the selection of plants for therapeutic application.

Novel Signposts on the Road from Natural Sources to Pharmaceutical Applications: A Combinative Approach between LC-DAD-MS and Offline LC-NMR for the Biochemical Characterization of Two Hypericum Species (H. montbretii and H. origanifolium)

The members of the genus Hypericum have great potential to develop functional uses in nutraceutical and pharmaceutical applications. With this in mind, we aimed to determine the chemical profiling and biological properties of different extracts (ethyl acetate, methanol and water) from two Hypericum species (H. montbretii and H. origanifolium). We combined two approaches (LC-DAD-MS and LC-NMR) to identify and quantify chemical compounds of the extracts. Antioxidant properties (free radical quenching, reducing power and metal chelating) and enzyme inhibitory effects (cholinesterase, tyrosinase, amylase and glucosidase) were determined as biological properties. The tested extracts were rich in caffeic acid derivatives and flavonoids, and among them, 3-caffeoyl quinic acid and myricetin-3-O-rhamnoside were found to be the main compounds. The total phenolic and flavonoid levels were determined to be 50.97-134.99 mg GAE/g and 9.87-82.63 mg RE/g, respectively. With the exception of metal chelating, the methanol and water extracts showed stronger antioxidant properties than the ethyl acetate extracts. However, different results were obtained for each enzyme inhibition assay, and in general, the ethyl acetate extracts present more enzyme-inhibiting properties than the water or methanol extracts. Results from chemical and biological analyses were combined using multivariate analysis, which allowed establishing relationships between composition and observed effects of the Hypericum extracts based on the extraction solvents. To gain more insights between chemical compounds and enzyme-inhibiting effects, we performed molecular docking analysis. We observed favorable interactions between certain compounds and the tested enzymes during our analysis, confirming the data obtained from the multivariate approach. In conclusion, the obtained results may shed light on the road from natural sources to functional applications, and the tested Hypericum species may be considered potential raw materials, with promising chemical constituents and biological activities.

Preliminary Evidence of the Efficacy of Nitric Acid Treatment in Onychomycosis

Onychomycosis is the main cause of toenail disorders and is produced by a fungal infection. It is becoming more prevalent because of new lifestyles and immunosuppression statuses. The therapeutic approach to onychomycosis is under considerable study because of the lengthy treatments that require strong patient commitment, the limited efficacy of treatments, the inclusion of active substances that can be hepatotoxic and cause pharmacological interactions, and/or the questionable efficacy of treatments due to a lack of clinical trials. This study responds to the demand for rapid treatment with minimal pharmacological interactions. Methods: The efficacy of nitric acid 60% treatment in patients with onychomycosis was monitored and studied. The antifungal efficacy of nitric acid was measured by microbiological culture before and after treatment and the clinical evolution of nail dystrophy was quantitatively measured by monitoring with the Onychomycosis Severity Index (OSI). Results: The results show that, with the protocol used, nitric acid 60% painlessly cured 40% (microbiologic cure) of the cases treated, and in all cases, clinical improvement was observed (p = 0.011). Conclusions: The treatment with nitric acid 60% is as efficient as conventional treatments, requires less patient compliance of the treatment and produces no pharmacological interactions, providing alternative treatment in the case of hepatotoxicity.

Perspective on the application of medicinal plants and natural products in wound healing: A mechanistic review

Wound is defined as any injury to the body such as damage to the epidermis of the skin and disturbance to its normal anatomy and function. Since ancient times, the importance of wound healing has been recognized, and many efforts have been made to develop novel wound dressings made of the best material for rapid and effective wound healing. Medicinal plants play a great role in the wound healing process. In recent decades, many studies have focused on the development of novel wound dressings that incorporate medicinal plant extracts or their purified active compounds, which are potential alternatives to conventional wound dressings. Several studies have also investigated the mechanism of action of various herbal medicines in wound healing process. This paper attempts to highlight and review the mechanistic perspective of wound healing mediated by plant-based natural products. The findings showed that herbal medicines act through multiple mechanisms and are involved in various stages of wound healing. Some herbal medicines increase the expression of vascular endothelial growth factor (VEGF) and transforming growth factor-β (TGF-β) which play important role in stimulation of re-epithelialization, angiogenesis, formation of granulation tissue, and collagen fiber deposition. Some other wound dressing containing herbal medicines act as inhibitor of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and inducible nitric oxide synthase (iNOS) protein expression thereby inducing antioxidant and anti-inflammatory properties in various phases of the wound healing process. Besides the growing public interest in traditional and alternative medicine, the use of herbal medicine and natural products for wound healing has many advantages over conventional medicines, including greater effectiveness due to diverse mechanisms of action, antibacterial activity, and safety in long-term wound dressing usage.

Medicinal plants as therapeutic options for topical treatment in canine dermatology? A systematic review

Background

Medicinal plants have been used traditionally since centuries for wound care and treatment of skin diseases both in human and animals. Skin diseases are one of the most common reasons for owners to take their dog to the veterinarian. The demands for treatment and prophylaxis of these diseases are broad. A wide range of bacteria including antibiotic-resistant bacteria can be involved, making the treatment challenging and bear an anthropo-zoonotic potential. The aim of this review is to systematically evaluate based on recent scientific literature, the potential of four medicinal plants to enrich the therapeutic options in pyoderma, canine atopic dermatitis, otitis externa, wounds and dermatophytosis in dogs.

Results

Based on four books and a survey among veterinarians specialized in phytotherapy, four medicinal plants were chosen as the subject of this systematic review: Calendula officinalis L. (Marigold), Hypericum perforatum L. agg. (St. John’s Wort), Matricaria chamomilla L. (syn. Matricaria recutita L., Chamomile) and Salvia officinalis L. (Sage). According to the PRISMA statement through literature research on two online databases a total of 8295 publications was screened and narrowed down to a final 138 publications for which full-text documents were analyzed for its content resulting in a total of 145 references (21 clinical, 24 in vivo and 100 in vitro references).

Conclusions

All four plants were proven to have antibacterial and antifungal effects of a rather broad spectrum including antibiotic-resistant bacteria. This makes them an interesting new option for the treatment of pyoderma, otitis externa, infected wounds and dermatophytosis. Marigold, St. John’s Wort and Chamomile showed wound-healing properties and are thus promising candidates in line to fill the therapeutic gap in canine wound-healing agents. St. John’s Wort and Chamomile also showed anti-inflammatory and other beneficial effects on healthy skin. Due to the wide range of beneficial effects of these medicinal plants, they should be taken into account for the treatment of dermatologic diseases in dogs at least in future clinical research.

Electronic supplementary material

The online version of this article (10.1186/s12917-019-1854-4) contains supplementary material, which is available to authorized users.

Antifungal Evaluation of Hypericum Triquetrifolium Polar Extracts against Fusarium spp

The chemical composition of different kinds of Hypericum triquetrifolium extracts was analyzed by LC-DAD-ESI-MS. Hyperoside, rutin, isoquercitrin and biapigenin were the main constituents. As these natural compounds were reported in the literature for their antifungal activity, the total extracts were tested for their antifungal activity against eight phytopathogenic strains of Fusarium species.

Antimicrobial and antibiofilm activity of polyurethane/Hypericum perforatum extract (PHPE) composite

Microbial accumulation in materials used in sectors such as medical, textile and food can lead to serious diseases, infections and uncontrollable problems. Many of the materials used in the above-mentioned industries have highly sensitive surfaces for microorganisms and cause colonization and biofilm formation. Colonization and biofilm formation threaten human health and they cause many diseases that result in death every year. Antimicrobial materials have an important role in combating pathogens. This article is about a new material with antibiofilm and antimicrobial properties combining polyurethane and Hypericum perforatum extract (PHPE) together. Antimicrobial effect of H. perforatum extract was determined against three clinical pathogens; C. albicans, E. coli and S. aureus. The highest antimicrobial activity of H. perforatum extract was found against S. aureus strain. Antibiofilm analysis results revealed that H. perforatum was also inhibited by the biofilm formation of S. aureus by 56.85%. The combination of polyurethane material and H. perforatum extract (PHPE) resulted in 92.85% decrease in S. aureus biofilm compared to control group. The reduction of S. aureus after H. perforatum incorporation was revealed by Scanning Electron Microscopy (SEM) study. The results show that the polyurethane material combined with H. perforatum extract inhibits the formation of S. aureus biofilm.

Bioactive compounds from Hypericum humifusum and Hypericum perfoliatum: inhibition potential of polyphenols with acetylcholinesterase and key enzymes linked to type-2 diabetes

CONTEXT

Natural products are reported to have a wide spectrum of pharmacological properties such as antimicrobial, anti-inflammatory and anti-cholinesterase. The genus Hypericum (Hypericaceae) is a source of a variety of molecules with different biological activities, notably hypericin and various phenolics.

OBJECTIVES

The goals of the present work were the determination of total phenolic and flavonoid content, hypericin and hyperforin concentration as well as the evaluation of biological of Hypericum humifusum L. (Hhu) and Hypericum perfoliatum L. (Hper).

MATERIALS AND METHODS

The various extracts of aerial parts were powdered, and then extracted with methanol. Antibacterial activity was performed according to minimum inhibitory concentration (MIC) and minimum bactericidal (MBC) methods against four Gram-positive bacteria, four Gram-negative bacteria and yeast.

RESULTS

The results revealed that H. humifusum, bear the highest total phenolic and flavonoid content (48-113 mg GAE/g and 8-41 mg RE/g, respectively) as well as hypericin (60-90 mg/g) and hyperforin (8-30 mg/g) concentration. Both species showed significant antioxidant activity as revealed by DPPH, FRAP, ABTS, and metal chelating assays. H. humifusum exhibited a strong acetylcholinesterase (3.86-4.57 mg GALAEs/g), α-glucosidase (0.73-2.55 mmol ACEs/g) and α-amylase (3-8 mmol ACEs/g) inhibitory activity. The extract of H. humifusum exhibited strong antibacterial activity mainly against Staphylococcus epidermidis, Staphylococus aureus, and Enterococcus faecium (MIC values ranging from 200 to 250 μg/mL). The highest antifungal activity was showed for H. perfoliatum extract (MIC value = 250 μg/mL).

CONCLUSION

The data suggest that H. humifusum could be used as valuable new natural agents with functional properties for pharmacology industries.

Hypericum perforatum: Influences of the habitat on chemical composition, photo-induced cytotoxicity, and antiradical activity

CONTEXT

Hypericin, isolated from Hypericum perforatum L. and about another 300 Hypericum species (Guttiferae), is one of the most powerful photosensitizers found in nature.

OBJECTIVE

The aim of this study was to assess the variability of chemical composition and biological activities of four H. perforatum samples, collected at different altitudes in the South Apennine of Italy.

MATERIALS AND METHODS

MTT assay was used to evaluate the antiproliferative activity of different samples concentrations (0.6-100 µg/mL) after irradiation at 365 nm. The inhibition of nitric oxide production was evaluated after 24 h of incubation using the macrophage cell line RAW 264.7 and sample solutions ranging from 12.5 to 1000 µg/mL. Antioxidant activities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and β-carotene bleaching test (ranges were 12.5-1000 and 1-400 µg/mL, respectively). Chemical composition was evaluated through HPTLC, and different contents of hypericin and rutin have been observed.

RESULTS

The most phototoxic sample was collected from Zumpano (no. 1 at 370 m), with IC50 values of 24.61 ± 0.02 μg/mL. Sample no. 1 showed also the best radical scavenging activity (IC50 value of 9.18 ± 0.03 μg/mL) and the best antioxidant activity (IC50 value of 10.04 ± 0.03 μg/mL after 30 min of incubation). Best activity of extract no. 1 was well in accordance with chemical data, including the phenolic total content and particular metabolome profile.

DISCUSSION AND CONCLUSION

This paper confirms the usefulness in maintaining the exploration of H. perforatum activities, in order to confirm its potentiality as a multipurpose plant.

Hypericum perforatum L. subsp. perforatum induces inhibition of free radicals and enhanced phototoxicity in human melanoma cells under ultraviolet light

OBJECTIVES

Our interest continues in discovering phytocomplexes from medicinal plants with phototoxic activity against human melanoma cells; thus the aim of the present study was to assess antioxidant, anti-inflammatory and phototoxic activity of Hypericum perforatum L. subsp. perforatum, and relate these properties to the plant's chemical composition.

MATERIALS AND METHODS

Components of H. perforatum subsp. perforatum were extracted by hydroalcoholic solution and chemical profiles of preparations (HyTE-3) performed by HPTLC. Linoleic acid peroxidation and DPPH tests were used to assess antioxidant activity, while MTT assay allowed evaluation of anti-proliferative activity with respect to A375 human melanoma cells after irradiation with UVA dose, 1.8 J/cm(2) . Inhibition of nitric oxide production of macrophages was also investigated.

RESULTS

HyTE-3 indicated better antioxidant activity with β-carotene bleaching test in comparison to DPPH assay (IC50 = 0.89 μg/ml); significant phototoxicity in A375 cells at 78 μg/ml concentration resulted in cell destruction of 50%. HyTE-3 caused significant dose-related inhibition of nitric oxide production in murine monocytic macrophage cell line RAW 264.7 with IC50 value of 342 μg/ml.

CONCLUSIONS

The H. perforatum subsp. perforatum-derived product was able to suppress proliferation of human malignant melanoma A375 cells; extract together with UVA irradiation enhanced phototoxicity. This biological activity of antioxidant effects was combined with inhibition of nitric oxide production.

Estimation of dermatological application of creams with St. John's Wort oil extracts

Oleum Hyperici, the oil extract of St. John’s Wort (SJW), is one of the oldest folk remedies, traditionally used in the topical treatment of wounds, bruises, ulcers, cuts, burns, hemorrhoids and also as an antiseptic. Considering the advantageous characteristics of emulsion applications, in the present study we have formulated three O/W creams containing 15% (w/v) of SJW oil extract as an active ingredient. The aim was to estimate dermatological application of the prepared creams for the abovementioned indications. The extracts were prepared according to the prescriptions from traditional medicine, however with different vegetable oils used as an extractant, namely: Olive, palm and sunflower oil. The investigated O/W creams demonstrated significant antiinflammatory effects in an in vivo double-blind randomized study, using a sodium lauryl sulphate test. Both skin parameters assessed in the study (electrical capacitance and erythema index), were restored to the baseline value after a seven-day treatment with the tested creams. Almost all investigated SJW oil extracts and corresponding creams displayed the same antimicrobial activity against the most of the investigated microorganisms with obtained minimal inhibitory concentrations values of 1,280 µg/mL, 2,560 µg/mL or >2,560 µg/mL.

A review of the antibacterial activity of Hypericum perforatum L

Hypericum perforatum L. (Hypericaceae) is a perennial herb that is commonly known as St. John's Wort. The plant has been valued for its important biological and chemical perspectives and its use in the treatment of infectious diseases has been documented in ethnobotanical reports. Most recent interest in H. perforatum has focused on its antidepressant effects, and only recently has its antimicrobial activity been evaluated against a number of bacterial and fungal strains. The present review gives a comprehensive summary of the ethnobotanical uses, chemical constituents and biological effects (antibacterial and antifungal) of this species. A comprehensive account of the chemical constituents including anthraquinone derivatives (naphthodianthrones), flavonoids, prenylated phloroglucinols, tannins and volatile oils is also included. Various types of preparations, ointments, creams and extracts prepared with and compounds isolated from this species have been found to possess a broad spectrum of biological and pharmacological effects such as antidepressant effects, wound-healing, antiviral and antimicrobial activity. The antibacterial activity of crude extracts can be related to the use of the herb as a wound healer in ancient times. The sole antibacterial principle isolated to date is a tetraketone, hyperforin, also thought to be responsible for the antidepressant activity of the herb. The available literature indicates that it has a higher antibacterial activity against Gram-positive than Gram-negative bacteria, and alcoholic extracts (methanolic/ethanolic) were shown to possess more pronounced activity than aqueous extracts. Based on the chemical and pharmacological characteristics of H. perforatum, we concluded that this species has beneficial therapeutic properties and has the potential for use as an effective adaptogenic herbal remedy.

Hypericins as potential leads for new therapeutics. Int J Mol Sci. 2010;11:562-594. [PMID: 20386655 PMCID: PMC2852855 DOI: 10.3390/ijms11020562]

70 years have passed since the first isolation of the naphthodianthrones hypericin and pseudohypericin from Hypericum perforatum L. Today, they continue to be one of the most promising group of polyphenols, as they fascinate with their physical, chemical and important biological properties which derive from their unique chemical structure. Hypericins and their derivatives have been extensively studied mainly for their antitumor, antiviral and antidepressant properties. Notably, hypericin is one of the most potent naturally occurring photodynamic agents. It is able to generate the superoxide anion and a high quantum yield of singlet oxygen that are considered to be primarily responsible for its biological effects. The prooxidant photodynamic properties of hypericin have been exploited for the photodynamic therapy of cancer (PDT), as hypericin, in combination with light, very effectively induces apoptosis and/or necrosis of cancer cells. The mechanism by which these activities are expressed continues to be a main topic of discussion, but according to scientific data, different modes of action (generation of ROS & singlet oxygen species, antiangiogenesis, immune responces) and multiple molecular pathways (intrinsic/extrinsic apoptotic pathway, ERK inhibition) possibly interrelating are implicated. The aim of this review is to analyse the most recent advances (from 2005 and thereof) in the chemistry and biological activities (in vitro and in vivo) of the pure naphthodianthrones, hypericin and pseudohypericin from H. perforatum. Extracts from H. perforatum were not considered, nor pharmakokinetic or clinical data. Computerised literature searches were performed using the Medline (PubMed), ChemSciFinder and Scirus Library databases. No language restrictions were imposed.