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Lipopolysaccharide (LPS) from gram-negative bacteria is a major factor that contributes to multiple organ failure including lung injury. Among LPS-induced metabolites, reactive oxygen species are considered to play a crucial pathogenic role in the lung damage. In this study, the effect of early administration of an antioxidant, a-lipoic acid (LA), on bronchoalveoar lavage fluid (BALF) lipid peroxidation, hydrogen peroxide (H2O2), sulphydryl group (-SH) concentration and total protein concentration was evaluated in rats with endotoxic shock induced by administration of LPS (Escherichia coli 026:B6, 30 mg/kg, i.v.). The animals were treated intravenously with normal saline or LA (60 mg/kg or 100 mg/kg i.v.) 30 min after LPS injection. Five hours after LPS or saline administration, the animals were sacrificed and BALF was obtained for measurements. The results showed that the levels of oxidative markers, thiobarbituric acid reactive substances (TBARS) and H2O2 were increased significantly in BALF, whereas they were decreased significantly on treatment with LA. The concentrations of -SH groups were significantly increased and total protein concentration was insignificantly decreased in the LPS/LA group. There was no difference in oxidative stress reduction between 60 mg/kg and 100 mg/kg doses. These results indicate that early administration of lipoic acid provides protective effects against endotoxin-induced oxidative stress in the lung and supports the idea that alpha-lipoic acid is a free radical scavenger and a potent antioxidant.
Using the general Hildebrand-Scatchard-Fedors theory of solubility, the mole fraction (x2) of solubility of phytochemicals contained in the dry green tea leaves was calculated which determines the profile of pharmacological activity.The applicative purpose of the study was to estimate the actual solubility of phytochemicals – S|real.| [mol/dm3] in water and in water-ethanol solutions of diversified polarity (εM) for their selective extraction and optimal formulation of oral solid dosage form.The basic physico-chemical and structural quantities of phytochemicals and corresponding mathematical equations of general Hildebrand-Scatchard-Fedors theory of solubility were used to calculate the actual solubility – S|real.| and the level of hydrophilic-lipophilic balance (HLB).The calculated actual solubility values – S|real.| [mol/dm3] collated with correlation equations enabled the assessment of phytochemical capability for the process of mass exchange on phase boundary. Correlation equations for the dependence log P = f (– log S|real.|) point to the structural preferences of phytochemicals in the kinetics of the mass exchange (diffusion) through the natural phase boundary.Calculations and correlations between the values characterizing the actual solubility – S|real.|, media polarity (water, ethanol and their solutions) and the partition coefficient (log P) including the level of hydrophilic-lipophilic balance (HLB) show that basing on thermodynamic components of the general Hildebrand-Scatchard-Fedors theory of solubility, the diffusion profile of phytochemicals contained in the green tea extract (Ext. Camellia sinensis L. aqu. siccum) through the biological phase boundary as well as optimal choice of the extraction medium for selective extraction of the class of phytochemicals can be estimated.
Introduction: Common ivy (Hedera helix) is a plant used successfully in the treatment of various ailments. This is possible owing to the unique set of substances contained in it such as large amount of saponins, flavonoids, phenolic acids and phytosterols as well as polyacetylenes and coumarins. All these substances have been used in the production of cosmetic and medicinal preparations. Clinical trials on the efficacy and safety of dry ivy leaf extract have shown its high efficacy, comparable to synthetic medications, and better tolerance of herbal drugs. Objective: Investigations were performed on model ivy leaf (Hedera helix) extracts which were created using a medium of diversified polarity (ԐM). Measurements of viscosity and surface activity on phase boundary were performed. During preformulation studies attention was drawn to the possibility of micellar solubilization of cholesterol and selected structures of nonsteroidal anti-inflammatory drugs (NSAIDs) – ketoprofen. Methods: Viscosity measurements of Extractum Hederae helicis e folium aqueous solutions and in 0.1 mol HCl were performed according to the Polish Standard with Ubbelohde dilution viscometer. The surface tension of aqueous solutions – Δγ25 of Hederae helicis e folium extracts was determined according to the Polish Standard with stalagmometric method . Critical micellar concentration (cmc) was calculated. This enabled to evaluate the dependence ΔG0 =2.303 RT× log cmc of the thermodynamic potential of micelle formation (ΔG0 ). Results: It has been confirmed in the conducted comparative studies that aqueous solutions of Extr. Hederae helicis e folium created with maltodextrin as well as with SiO2 – maltodextrin result in micellar solubilization. The increase of granulometric size of cholesterol particle to Ø 1.60 mm decreased the amount of solubilized cholesterol but solubility preferences of the extracts were maintained. Conclusions: Model extracts produced from Hederae helicis e folium with diversified polarity of the extraction medium (water – ethanol) are characterized by appropriate solubility of the components which results not only from the presence of chlorophyll and its derivatives in the extract but also from the technique used for spray drying of the extract.
Green tea offers not only pleasant, delicate flavor, but also provides health benefits. The extract contains, among others, polyphenols responsible for antioxidant and anti-inflammatory properties. They reduce the risk of cancer and their presence exerts preventive activity against cardiovascular diseases. Analysis of selected physicochemical and solubilizing properties of pharmacopoeial-true solutions of dry green tea extract. The caffeine content was determined in the extract and in dry residue after solubilization by high performance liquid chromatography. The process of micellar solubilization of cholesterol granules and ketoprofen was carried out in model solutions of green tea extract. The obtained results indicate that the prepared ‘ex tempore’ leaf green tea infusion subjected to short thermal exposure will be characterized by significant solubilization abilities. The outcomes of the research pointed to the possibility of developing a solid oral dosage form with titrated dry green tea extract of expected pharmacotherapeutic profile.
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