[Show abstract][Hide abstract] ABSTRACT: Molecular inclusion complexes of usnic acid (UA) with β-cyclodextrin (β-CD) and 2-hydroxypropyl β-cyclodextrin (HP β-CD) were prepared by the co-precipitation method in the solid state in the molar ratio of 1:1. Structural complexes characterization was based on different methods, FTIR, 1H NMR, XRD and DSC. Parallel to the complex by the above methods, corresponding physical mixtures of UA with cyclodextrins and complexing agents (β-CD, HP β-CD and UA) were analyzed. The results of DSC analysis showed that, at around 200 °C, the endothermal peak in the complexes with cyclodextrins originating from the UA melting has disappeared. Complex diffractogram patterns do not contain peaks characteristic for the pure UA. They are more appropriate to cyclodextrin diffractogram. This fact points to the molecular encapsulation of UA in the cyclodextrin cavity. Chemical shifts in 1H NMR spectra after the inclusion of UA into the cyclodextrin cavity, especially H-3 protons (0.0012 and 0.0102 ppm in the β-CD and HP β-CD, respectively) and H-5 and H-6 (0.0134 ppm) and hydrogen from CH3 (0.0073 ppm) HP β-CD also points to the formation of molecular inclusion complexes. The improved solubility of UA in water was achieved by molecular incapsulation. In the complex with β-CD the solubility is 0.3 mg/cm3, with HP β-CD 4.2 mg/cm3 while the uncomplexed UA solubility is 0.06 mg/cm3. The microbial activity of UA and both complexes was tested against eight bacteria and two fungi and during the test no reduced activity of UA in the complexes was observed.
No preview · Article · Jun 2013 · Journal of Inclusion Phenomena
[Show abstract][Hide abstract] ABSTRACT: Venous ulcers (ulcus cruris venosum) are a common chronic disease that requires continuing treatment and significantly influences a patient's way of life. The therapeutic effects of the ointment Herbadermal on epithelialization and microbial flora of venous ulcers in 25 patients (10 men and 15 women) were tested over a 7-week period. The major components of the ointment are extracts of garlic, St. John's wort, and calendula.
The patients were over 18 years of age, with ulceration of the lower leg no longer than 2 months or recurrent ulceration during the last 6 months. The involved patients did not use any other phytomedicines or supportive therapies. Parameters were evaluated before the treatment and every 2 weeks during the period of 7 weeks. The total treatment response was evaluated on the basis of epithelialization, granulation, fibrin deposits, exudation, and edema.
The percentage of epithelialization was 99.1% after 7 weeks, without significant effects on the microbial flora.
This combination of extracts can be recommended as topical treatment for wound healing because of its epithelizing, anti-erythematous, and anti-edematous properties.
No preview · Article · Feb 2012 · Forschende Komplementärmedizin / Research in Complementary Medicine
[Show abstract][Hide abstract] ABSTRACT: New, simple, cost effective, accurate and reproducible UV-spectrophotometric methods were developed and validated for the estimation of sodium usnate in pharmaceutical preparations. Sodium usnate was estimated at 290 nm in water and phosphate buffer (pH 3):methanol (11:20 V/V). Beer's law was obeyed in the concentration range of 0.1-5 μg·cm-3 (r = 0.997) in water and 1-12 μg·cm-3 (r = 0.999) in the phosphate buffer:methanol. The apparent molar absorptivity and Sandell's sensitivity coefficient were found to be 3.16×104 dm3·mol-1·cm-1 and 11.58 ng·cm-2/0.001 A in water and 3.72×104 dm3·mol-1·cm-1 and 9.83 ng·cm-2/0.001 A in phosphate buffer:methanol, respectively, indicating the high sensitivity of the proposed methods. These methods were tested and validated for various parameters according to ICH guidelines. The detection and quantitation limits were found to be 0.0721 and 0.2163 μg·cm-3 in water and 0.163, 0.489 μg·cm-3 in phosphate buffer:methanol, respectively. The proposed methods were successfully applied for the determination of sodium usnate in pharmaceutical preparations. The results demonstrated that the procedure is accurate, precise and reproducible (R.S.D. < 2 %).
No preview · Article · Jan 2010 · Macedonian Journal of Chemistry and Chemical Engineering
[Show abstract][Hide abstract] ABSTRACT: The newly established instrumentation of HPLC/DAD, FTIR, and NMR techniques have been applied for simultaneous identification
and physicochemical compatibility determination of the potential major antiseptic constituents (Hypericum perforatum L. and Usnea barbata extracts) which can be present in some new origin pharmaceutical preparation. Based on the obtained results the conclusion
is that a simultaneous use of the analyzed constituents in production of some new preparations with antiseptic properties
is possible. The chromatographic separation of antiseptic mixture was performed on a RP-HPLC C18 column. For the NMR detection,
the analytes eluted from LC column were trapped and hereafter transported into the NMR flow-cell. The NMR and FTIR techniques
allowed the characterization of the major constituent of Hypericum perforatum L., mainly hypericin, as well as of Usnea barbata, mainly usnic acid.
No preview · Article · Sep 2009 · Russian Journal of Physical Chemistry