No abstract

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.

There is a worldwide ongoing investigation for novel natural constituents with cytotoxic and antioxidant properties. The aim of this study was to investigate chemical profile and stated biological activities of the supercritical CO2 extract (SCE) of old man’s beard compared to the extracts obtained using the conventional techniques (Soxhlet extracts and macerate). The most abundant compound identified was usnic acid, which content was inversely proportional to the polarity of the solvent used and was the highest in the SCE, which was the sample revealing the highest cytotoxic activity in tested tumor cell lines (B16 mouse melanoma and C6 rat glioma), with lower IC50 values compared to pure usnic acid. Further investigations suggested both SCE and usnic acid to induce apoptosis and/or autophagy in B16 and C6, indicating higher cytotoxicity of SCE to be related to the higher degree of ROS production. A good correlation of usnic acid content in the extracts and their antioxidant capacity was established, extricating SCE as the most active one. Presented results support further investigations of SCE of old man’s beard as a prospective therapeutic agent with potential relevance in the treatment of cancer and/or in oxidative stress-mediated conditions.

No abstract

The objective of this work was to investigate and profoundly characterize low-energy nanoemulsions as multifunctional carriers, with slight reference to dermal administration. An evidence-based approach was offered for deepening the knowledge on their formation via spontaneous emulsification. Curcumin, a compound of natural origin, potentially powerful therapeutic, was chosen as a model API. Due to curcumin's demanding properties (instability, poor solubility, low permeability), its potentials remain unreached. Low-energy nanoemulsions were considered carriers capable of overcoming imposed obstacles. Formulation consisting of Polysorbate 80 and soybean lecithin as stabilizers (9:1, 10%), medium-chain triglycerides as the oil phase (10%) and ultrapure water was selected for curcumin incorporation in 3 different concentrations (1, 2 and 3 mg/mL). Physicochemical stability was demonstrated during 3 months of monitoring (mean droplet size: 111.3-146.8 nm; PDI < 0.2; pH: 4.73-5.73). Curcumin's release from developed vehicles followed Higuchi's kinetics. DPPH (IC50 = 0.1187 mg/mL) and FRAP (1.19 ± 0.02 mmol/g) assays confirmed that curcumin acts as a potent antioxidant through different mechanisms, with no alterations after incorporation in the formulation. High biocompatibility in line with antigenotoxic activity of curcumin-loaded formulations (protective and reparative) was estimated through Comet assay. A multidisciplinary approach is needed to fully characterize developed systems, directing them to more concrete application possibilities.

No abstract

Usnic acid is one of the most investigated lichen secondary metabolites, with several proven biological properties with potential medical relevance. However, its unfavorable physico-chemical properties, as well as observed hepatotoxicity, have discouraged wide-range utilization of usnic acid as a promising therapeutic agent. In accordance with the growing research interest in the development of nanotechnology, especially in the arena of preparations based on natural sources of medicinal compounds, usnic acid incorporated into nano- and microsized colloidal carriers has been a subject of a large number of publications. Therefore, this review discusses the overall results of the studies dealing with usnic acid encapsulated into lipid-based, polymeric and nonorganic micro- and/or nanocarriers, as potential drug delivery systems for this natural compound, in an attempt to introduce its usage as a potential antitumor, antimicrobial, wound-healing, antioxidative and anti-inflammatory drug.

Bilberry represents a valuable source of antioxidant substances responsible for its application for the treatment of different conditions (such as inflammation, cardiovascular disease, cancer, diabetes, and different age-related diseases) associated with increased oxidative stress. As oxidative stress might cause skin impairments, we aim to evaluate a topical preparation containing bilberry leaves extract and bilberry seeds oil, obtained as a byproduct of the food industry. To obtain the extracts, the conventional maceration technique for leaves, and supercritical carbon dioxide extraction for seeds were employed. The chemical profile of both actives was achieved by HPLC and GC methods, revealing the presence of phenolic acids (chlorogenic being the most abundant), flavonoids (isoquercetin in the highest amount), and resveratrol in leaves extract, while in seeds oil the essential ω-3 and ω-6 fatty acids were determined in favorable ratio, almost being 1. Antioxidant potential of the wild bilberry extract and seed oil was evaluated using in vitro DPPH and FRAP assays. Finally, effects of the oil-in-water creams with mentioned wild bilberry isolates on the skin were investigated in an in vivo study conducted on healthy human volunteers, revealing the significant beneficial effects when topically applied.