Ana Radovanovic

The use of dry Jerusalem artichoke as a functional nutrient in developing extruded food with low glycaemic index

This study considers the use of dry Jerusalem artichoke (JA) as a functional nutrient in developing food products with enhanced nutritional characteristics and low glycaemic index (GI). Three different formulations based on buckwheat and JA were developed and processed using extrusion technology. Nutritional properties including the levels of total dietary fibre (TDF), protein, inulin, total carbohydrates and lipids were analysed. A clinical study was performed on ten healthy volunteers (aged between 21 and 56) to determine the level of GI and glycaemic load (GL). The results revealed that JA significantly (P<0.05) increased the levels of TDF and inulin whilst decreasing carbohydrates, lipids and proteins. The resulting products had a significant (P<0.05) effect on IAUC between reference food and extruded products, GI and GL. Samples containing 80% of Jerusalem artichoke were considered as a low GI food whilst samples containing 30% and 60% of Jerusalem artichoke as a medium GI food. A similar trend was seen in terms of GL.

Population pharmacokinetics of 25-hydroxyvitamin D in healthy young adults.

OBJECTIVES The aim of our study was to develop a population pharmacokinetic (PPK) model for 25-hydroxyvitamin D clearance in a healthy young adult population in Serbia. METHODS Study sample consisted of 70 healthy young students of the Faculty of Medical Science, University of Kragujevac, Serbia, with a mean age and body mass index of 22.39 ± 1.82 years and 21.31 ± 2.69 kgm-2, respectively. Non-linear mixed-effect modeling (NONMEM) software was used for data analysis. A validation set of 16 participants was used to estimate the predictive performance of the pharmacokinetic model. RESULTS In the base model (without covariates), we had parameter estimates of 0.01 L/h for apparent clearance, 0.25 L for apparent volume of distribution, while value of minimum objective function (MOF) was 383.468. The full regression model was established by estimating the effects of 12 covariates. Mean intake of vitamin D from foods (DD) and value of phosphate in serum (PHO) were covariates included in the final model, while others were excluded in this process. The estimated value in the final MOF model was 274.555. The final regression model formula was: clearance (CL) (L/h) = 0.0711 + 0.738 x DD + 0.618 x PHO. CONCLUSIONS The PPK model obtained determined clearance of 25-hydroxyvitamin D in a healthy young adult population in Serbia. Mean intake of vitamin D from foods and serum phosphate level are the most important covariates that influence value of 25-hydroxyvitamin D clearance in healthy young adults.

Evaluation Of Potential Cytotoxic Effects Of Herbal Extracts

Abstract Herbal medicines have played an important role in treating different diseases since ancient times. Bioactive components of medicinal plants are a good starting point for discovering new drugs such as chemotherapeutics. Currently, there are four classes of plant-derived chemotherapeutic drugs used in clinical practice. However, to discover new potential cytotoxic molecules, the research effort on herbal extracts has not diminished. The aim of this review was to evaluate the chemical constituents of plants that possess cytotoxicity, the signalling pathways responsible for this effect, and the influence of solvent polarity on potential cytotoxic effect and to present the cytotoxic activity of selected herbal extracts. The polyphenolic, anthraquinon, diterpneoid, triterpenoid, flavonoid, betulinic acid and berberine content contributes to cytotoxicity of herbal extracts. The inhibitory effect on cancer cells viability could be a consequence of the non-apoptotic processes, such as cell cycle arrestment, and the apoptotic process in tumour cells through different signalling pathways. The influence of solvent polarity on potential cytotoxic effect of herbal extracts should not be ignored. In general, the best cytotoxic activity was found in nonpolar and moderately polar herbal extracts. The herbal extract with IC50 below 30 μg/ml could be considered a very strong cytotoxic agent. Considering that many antitumor drugs have been discovered from natural products, further research on plants and plant-derived chemicals may result in the discovery of potent anticancer agents.

CUTANEOUS TOLERANCE OF SEA BUCKTHORN OIL EMULSION

Introduction: Sea buckthorn oil ( Hippophae rhamnoides L.) is medically used both externally and internally, but the external application is unsutable due to its liquid, lipophylic and highly colored nature. These difficulties could be overbriged by formulation of semisolid emulsion with sea buckthorn oil. Previous research on this formulation showed that it has higher wound healing potential then sea buckthorn oil, possesing enhanced structure of liquid crystals, stability and suitability for topical use. Aim: The aim of this investigation was to complete characterization of proposed emulsion, by testing its potential for causing skin irritation. Methods: The emulsion was prepared by standard emulsifying techniques using a combination of surfactants that form an enhanced structure of liquid crystals. Amount of 40% of sea buckthorn oil was incorporated. Since results of previous research on this formulation show wound healing effect on an animal model, we also tested skin tolerance of it on animal skin model. Evaluation was done by Draize test which measures level of skin changes of rabbit skin. Results: There was absence of edema or erythema type of irritation after 2h, 24h, 48h, 72h and 7 days of application of semisolid emuslion with sea buckthorn oil. Conclusion: This study confirmed that combination of the proposed ingredients is adequate and the concentrations of surfactants used to form stable emulsion were appropriate also for skin application. The proposed formulation of emulsion with sea buckthorn oil exerted percutaneous tolerance and could be safely applied on the skin. Key words: sea buckthorn oil, emulsion, topical use, irritation

Cutaneous Effects of Sea Buckthorn Oil Emulsion

Abstract Sea buckthorn oil (Hippophae rhamnoides L.) is medically used both externally and internally, but the external application is unsuitable due to its liquid, lipophilic and highly coloured nature. These difficulties could be overcome by a formulation of semisolid emulsion with sea buckthorn oil. Previous research on this formulation showed that it has higher wound healing potential than sea buckthorn oil, possessing an enhanced structure of liquid crystals, stability and suitability for topical use. The aim of this investigation was to completely characterizise a proposed emulsion by testing skin effects, such as moisturising potential, skin pH and potential to cause skin irritation. The emulsion was prepared by standard emulsifying techniques using a combination of surfactants that form an enhanced structure of liquid crystals. Approximately 40% of sea buckthorn oil was incorporated. The moisturising potential and skin pH were tested on the healthy skin of volunteers. Skin tolerance was tested on a rabbit skin model and evaluated by the Draize test. The tested emulsion containing sea buckthorn oil did not cause a significant change in skin pH, while it significantly increased skin hydration. Th ere was an absence of edema or erythema type of irritation after 2 h, 24 h, 48 h, 72 h and 7 days of application of the emulsion with sea buckthorn oil. The tested formulation shows good moisturizising effects and does not cause human or animal skin irritation. Th e study confi ms that the combination of the proposed ingredients in a sea buckthorn oil emulsion is adequate and could be safe for skin application Sažetak Ulje pasjeg trna (Hippophae rhamnoides L.) se u medicinske svrhe upotrebljava kako za eksternu tako i za internu primenu, pri čemu je eksterna primena nepogodna usled njegove tečne konzistencije, lipofi lne prirode i intenzivne obojenosti. Navedeni nedostaci bi se mogli prevazići formulacijom polučvrstih emulzija sa uljem pasjeg trna. Prethodna ispitivanja ove formulacije su pokazala da poseduje znatno veći potencijal za zarastanje rana u odnosu na ulje pasjeg trna, unapređenu strukturu tečnih kristala, stabilnost i pogodnost za lokalnu primenu. Sprovedeno istraživanje imalo je za cilj da upotpuni karakterizaciju predložene formulacije, testirajući efekte na koži- hidrirajući potencijal, pH kože i potencijal za izazivanje kožnih iritacija. Emulzija je pripremljena standardnim tehnikama emulgovanja, korišćenjem kombinacije surfaktanata kojima se formira poboljšana struktura tečnih kristala pri čemu je ulje pasjeg trna je bilo inkorporirano u količini od 40%. Hidrirajući potencijal i pH kože su bili testirani na koži zdravih volontera. Tolerancija kože je testirana na modelu zečje kože i procenjivana pomoću Draize-ovog testa. Ispitivana emulzija sa uljem pasjeg trna nije pokazala značajne promene pH kože, dok je pokazan značajan hidrirajući efekat. Nisu se javile kožne iritacije, tipa edema ili eritema, nakon 2h, 24h, 48h, 72h i 7 dana od aplikacije emulzije sa uljem pasjeg trna. Evaluirana formulacija ne izaziva iritaciju ni humane ni životinjske kože i pokazuje dobar hidrirajući efekat. Studija potvrđuje da je kombinacija preloženih sastojaka u emulziji sa uljem pasjeg trna adekvatna i može se bezbedno primenjivati na koži.