Propolis - quality analysis and use in topical formulations.

The aim of this study was to produce propolis extracts, assess their quality and effect on skin cells and determine the penetration of active ingredients from designed semi-solid topical formulations. The use of higher-concentration ethanol and a larger amount of raw material allows extracting a larger quantity of active ingredients from raw propolis. Ultrasound extraction is an effective method for the production of aqueous extracts of propolis. The results show that depending on concentration, propolis extracts reduce the viability of keratinocytes. The phenolic compounds under observation penetrated the epidermis and dermis from designed formulations. The base of semi-solid formulation influences the efficacy of propolis preparations. The overall quantity of phenolic compounds that penetrated the skin was around 2 % from the ointment and 1.5 % from the cream.

MODELING AND BIOPHARMACEUTICAL EVALUATION OF SEMISOLID SYSTEMS WITH ROSEMARY EXTRACT.

Scientific literature provides a great deal of studies supporting antioxidant effects of rosemary, protecting the body's cells against reactive oxygen species and their negative impact. Ethanol rosemary extracts were produced by maceration method. To assess biological activity of rosemary extracts, antioxidant and antimicrobial activity tests were performed. Antimicrobial activity tests revealed that G+ microorganisms are most sensitive to liquid rosemary extract, while G-microorganisms are most resistant to it. For the purposes of experimenting, five types of semisolid systems were modeled: hydrogel, oleogel, absorption-hydrophobic ointment, oil-in-water-type cream and water-in-oil-type cream, which contained rosemary extract as an active ingredient. Study results show that liquid rosemary extract was distributed evenly in the aqueous phase of water-in-oil-type system, forming the stable emulsion systems. The following research aim was chosen to evaluate the semisolid systems with rosemary exctract: to model semisolid preparations with liquid rosemary extract and determine the influence of excipients on their quality, and perform in vitro study of the release of active ingredients and antimicrobial activity. It was found that oil-in-water type gel-cream has antimicrobial activity against Staphylococcus epidermidis bacteria and Candida albicans fungus, while hydrogel affected only Candida albicans. According to the results of biopharmaceutical study, modeled semisolid systems with rosemary extract can be arranged in an ascending order of the release of phenolic compounds from the forms: water-in-oil-type cream < absorption-hydrophobic ointment < Pionier PLW oleogel < oil-in-water-type eucerin cream < hydrogel < oil-in-water-type gel-cream. Study results showed that oil-in-water-type gel-cream is the most suitable vehicle for liquid rosemary extract used as an active ingredient.

DETERMINATION OF ANTIMICROBIAL ACTIVITY OF CHLORHEXIDINE GEL.

Many researchers have advocated in recent times that antiseptic use in healing wounds should be discouraged. Antiseptics have been found to retard healing of wounds. Poloxamer 407 shows thermoreversible properties, which are of the utmost interest in optimizing drug formulation (fluid state at room temperature facilitating administration and gel state above sol-gel transition temperature, at body temperature, promoting prolonged release of pharmacological agents). Chlorhexidine, a commonly used antiseptic, is known to be less toxic on granulation cells. Acting as an antiseptic, it is an effective bactericidal agent against the most categories of microbes, including bacteria, yeast, and viruses. Objective of this study was to evaluate antimicrobial activ- ity of chlorhexidine containing poloxamer gel to Gram-positive and Gram-negative bacteria in vitro. Chlorhexidine gels and chlorhexidine aqueous solutions have different antibacterial activity to S. amis, E.faecalis, E. coli and P. aemginosa strains in vitro. It depends on concentration and dosage form of antiseptic. Study results confirmed that antimicrobial activity of gel depends on active ingredient concentration in antiseptic. The best inhibition effect for both of reference and wild-type bacteria was obtained for 1% chlorhexidine gel. Summarizing the results and assessing the characteristics of the gel ingredients, it can be suggested using chlorhexidine gels in veterinary medicine.

Total phenolic content and antimicrobial activity of different lithuanian propolis solutions.

The manufacture of ethanol-free propolis solutions offers a broader application. A few trials with Lithuanian propolis have been conducted. The aims of the study are to manufacture propolis water and water-free solutions and evaluate the quality and antimicrobial activity of these solutions. The studied solutions containing 2.5%, 5%, and 10% propolis are prepared. As solvents, purified water, 70% v/v ethanol, 96.3% v/v ethanol, propylene glycol, and their systems were used. Determination of total levels of phenolic compounds (FAE mg/g) is based on colour oxidation-reduction reaction using Folin-Ciocalteu reagent under alkaline conditions and performed at 765 nm wavelength using UV spectrophotometer. The highest content of phenolic compounds was determined in solutions containing 10% propolis extracts, and the lowest amounts in 2.5% propolis extracts. The water extracted the lowest amount of phenolic compounds from crude propolis, ethanol extracted the highest amount, and propylene glycol ranked the middle position. It is determined that technological parameters (stirring, temperature) contribute to content of phenolic compounds. During microbiological study, MICs were determined. The studies showed that water extracted propolis solutions and solvents mixture did not inhibit the growth of the studied microorganisms, and propolis solutions in propylene glycol were found to have antimicrobial activity.

Analysis of content of phenolic acids in Lithuanian propolis using high-performance liquid chromatography technique.

UNLABELLED: The aim of the study was to analyze phenolic acids in Lithuanian propolis and to compare it with the composition of propolis in neighboring countries (Latvia and Poland) according to the predominant flora in the collecting places. The study was also aimed at the evaluation of the effect of the layer thickness (mm) of the harvested propolis on the quality of the raw material in determining the amount of phenolic acids. MATERIALS AND METHODS: The object of the study was propolis collected in Lithuania, Poland, and Latvia in late July of 2006 and 2007. The qualitative and quantitative analysis of phenolic acids was performed using the high-performance liquid chromatography technique (HPLC). RESULTS: The results of the study showed that the quantitative and qualitative composition of phenolic acids in propolis depended on the plants from which the bees in the area collected substances for the raw material of propolis. The predominant phenolic acids were determined to be ferulic and coumaric acids, and they may be among the main indicators of quality in the standardization of the raw material and preparations of propolis. CONCLUSION: We created an HPLC-based analysis method for the identification and quantification of phenolic acids in propolis. The variety of phenolic acids in propolis depends on the vegetation predominating in the harvesting area. Studies have shown that the highest amount of phenolic acids is observed in propolis harvested in areas characterized by the predominance of deciduous trees and meadows. Results have also shown that ferulic and coumaric acids are the predominant phenolic acids in propolis. The thickness of the layer of the collected propolis in the hive also influences its chemical composition.

Analysis of the antimicrobial activity of propolis and lysozyme in semisolid emulsion systems.

Propolis as an active natural substance is attractive due to its antimicrobial and antimycotic properties. Lysozyme was added to semisolid dermatological preparations as a complementary substance capable of potentiating their antimicrobial and antimycotic effect; this substance has been used for several decades as a preservative in food industry. The aim of this study was to model a semisolid emulsion system (o/w) for cutaneous use with moisturizing and antimicrobial properties, where the active substances would be propolis and/or lysozyme. The microbiological examination was performed under aseptic conditions. The microbiological examination was aimed at determining the antimicrobial efficacy of the studied preparation in the solid growth media using the wells technique. The results of the antimicrobial assay showed that the effectiveness of propolis against the growth of S. aureus was intensified by the lysozyme introduced into the emulsion systems. In addition to that, the results of examinations showed that the active substance propolis in emulsion systems more efficiently inhibited spore bacteria (Bacillus cereus) than lysozyme did, yet lysozyme had a more pronounced antimycotic (against Candida albicans) effect, compared to propolis. All studied cream samples inhibited the growth of Gram-negative microorganisms (Escherichia coli). The results of this study suggest that the application of propolis and lysozyme as the active substances may increase the antimycotic and antibacterial effect of the studied preparations.

[Development of technology of sodium cromoglycate eye drops]. / Natrio kromoglikato akiu lasu technologijos sukurimas.

UNLABELLED: Ophthalmologic preparation of sodium cromoglycate can be successfully employed both as a preventive means and as a treatment of allergic eye diseases. The objective of this research was to select the composition of sodium cromoglycate eye drops and to develop the technology using which it would be possible to produce aqueous and prolonged-release sodium cromoglycate eye drops. MATERIALS AND METHODS: Sodium cromoglycate 2% and 4% solution-eye drops; sodium cromoglycate 4% solution--prolonged-release eye drops. In order to evaluate the quality and stability of these eye drops methods of qualitative and quantitative analysis were applied. RESULTS: On the basis of the research data compositions of 2% and 4% sodium cromoglycate eye drops and prolonged-release sodium cromoglycate 4% eye drops were chosen. Experimental batches were prepared and investigated according to developed experimental schemes of technologies of 2% and 4% sodium cromoglycate eye drops and prolonged-release sodium cromoglycate 4% eye drops. Technological properties of polymeric substances, i.e. hypromellose and polyvinyl alcohol, and their solutions were evaluated. The obtained results showed that polyvinyl alcohol improved the solubility of sodium cromoglycate in water. For sterile filtration of the viscous solution of prolonged-release sodium cromoglycate eye drops the filtration system of two prefilters and sterilizing membrane filter was developed and optimal temperature of 35-40 degrees C of filtered solution was determined.

[Study of biopharmaceutic characteristics of cromoglycate eye drops]. / Natrio kromoglikato akiu lasu biofarmaciniu charakteristiku tyrimas.

One of the factors influencing the release of active substance from the drug formulation is presence of polymeric substance resulting in increase of viscosity of eye drops. Diffusion of sodium cromoglycate from polyvinyl alcohol 1.4%, 3% solutions and hypromellose 1% aqueous solution was investigated using in vitro method and diffusion coefficients were evaluated. Release of sodium cromoglycate from polyvinyl alcohol 1.4%, 3% solutions and hypromellose 1% aqueous solution was slower than the release from aqueous solution of sodium cromoglycate. The sodium cromoglycate diffusion from ophthalmic vehicle process kinetics was influenced by viscosity of these solutions and nature of the used polymers. The diffusion process of sodium cromoglycate from 1.4% PVA solution was more intensive if compared to diffusion from 1% hypromellose solution. The influence of excipients on sodium cromoglycate diffusion from eye drop formulation was evaluated when polymeric solutions have been used as vehicles.

[Development of formulation of hipromellose eye drops (artificial tears)]. / Hipromeliozes akiu lasu (dirbtines asaros) technologijos sukurimas.

The task of this research work was to develop a formulation of hipromellose ophthalmic preparation by determining optimal composition of active ingredients and excipients. Aqueous solution of hipromellose 1% and sorbitol 4.5% was prepared with addition of phosphate buffer (pH 7.05) and preservative cetrimide 0.01%. Sterile filtration was used for solution sterilization. Polimeric membrane prefilters of 1 microm, 0.45 microm and 0.22 microm pore size were employed as sterilizing filter. It is recommended to increase the temperature up to 35-38 degrees C for more efficient filtration of the solution. Quality parameters and analytical methods for quality control have been developed to control the quality and to evaluate the stability of hipromellose eye drops during their storage for 24 months. The obtained results confirmed the sterility and stability of hipromellose eye drops for the period of two years.

[Hormonal anti-inflammatory and anti-allergic ocular drugs and their use (review of the literature)]. / Hormoniniai priesuzdegiminiai-antialerginiai oftalmologiniai vaistai ir ju vartojimas (literaturos apzvalga).

Recent reports have shown a worldwide increase of allergic diseases during the past 10-20 years. One of the risk factors of allergic diseases is atmospheric pollution. Ocular allergic disorders contain 2-15 percents of all allergic diseases. Corticosteroids have been useful in control of inflammatory and immunologic diseases of the eye. The anti-inflammatory effects of corticosteroids are nonspecific and they inhibit inflammation without regard to cause. Topical therapy is effective in anterior segment of eye. New modes of delivering a drug to the eyes are being actively explored. Formulation characteristics markedly increase drug residence time in the eye and absorption. The difficulty for drugs to penetrate through the cornea is combined with their rapid removal through the tear system and their dilution by reflex tearing.