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Encapsulation may protect viable probiotic cells. This study aims at the evaluation of a bambara groundnut protein isolate (BGPI)-alginate matrix designed for encapsulating a probiotic Lactobacillus rhamnosus GG. The response surface methodology was employed to gain the optimal concentrations of BGPI and alginate on encapsulation efficiency and survival of encapsulated cells. The capsules were prepared at the optimal combination by the traditional extrusion method composed of 8.66% w/v BGPI and 1.85% w/v alginate. The encapsulation efficiency was 97.24%, whereas the survival rates in an acidic condition and after the freeze-drying process were 95.56% and 95.20%, respectively-higher than those using either BGPI or alginate as the encapsulating agent individually. The designed capsules increased the probiotic L. rhamnosus GG survival relative to free cells in a simulated gastric fluid by 5.00 log cfu/ml after 3 h and in a simulated intestinal fluid by 8.06 log cfu/ml after 4 h. The shelf-life studies of the capsules over 6 months at 4 °C and 30 °C indicated that the remaining number of viable cells in a BGPI-alginate capsule was significantly higher than that of free cells in both temperatures. It was demonstrated that the BGPI-alginate capsule could be utilized as a new probiotic carrier for enhanced gastrointestinal transit and storage applied in food and/or pharmaceutical products., Competing Interests: Conflict of Interest: All authors declare no conflicts of interest in this study.

A lactobacillus strain isolated from a vaginal tract of a healthy woman was examined in vitro for its probiotic potential. This strain, identified as Lactobacillus fermentum SK5, was able to survive at pH 3-4 and 0.1-0.2% bile, and unaffected by pepsin (3 g l(-1)) and pancreatin (1 g l(-1)), but was susceptible to all tested antibiotics except metronidazole. L. fermentum SK5 had an antimicrobial potential against gastrointestinal pathogenic Escherichia coli and vaginal pathogenic Gardnerella vaginalis. The effective substance was suspected to be a bacteriocin-like compound with a molecular weight of more than 10 kDa, but hydrogen peroxide was also detected. Further studies revealed that L. fermentum SK5 had good autoaggregation characteristic and a high surface hydrophobicity that enhanced its adhesion ability to epithelial cells and for biofilm formation. This lactobacillus showed coaggregation with E. coli and G. vaginalis to affect their adhesion and colonization. The adhesion of L. fermentum SK5 to HeLa, HT-29 and Caco-2 cells and its inhibition of E. coli and G. vaginalis adherence to these cells were demonstrated. These incidences provided evidence of the possible colonization of L. fermentum SK5 that would prevent binding and growth of E. coli and G. vaginalis onto intestinal and vaginal epithelial cells. On the basis of the ability of L. fermentum SK5 to inhibit pathogenic microorganisms through coaggregation and antimicrobial substances, it is likely that this lactobacillus strain could be a potential probiotic candidate for beneficial use in protecting against gastrointestinal and vaginal microbial infections., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The aims of this study were to develop a transdermal patch for selective controlled delivery of the active S-enantiomer from racemic propranolol, and to evaluate its performance in vivo using Wistar rats. A molecularly imprinted polymer (MIP) thin-layer composited cellulose membrane with selectivity for S-propranolol was employed as the enantioselective-controlled release system. The effect of gel reservoir (poloxamer and chitosan) on enantioselective delivery was investigated. The chitosan gel allowed excellent selectivity for delivery of the S-propranolol enantiomer, whilst the more rheologically structured poloxamer gel formulation provided no selective release of S-propranolol. The chitosan gel exhibited high flux and had the ability to enantioselective deliver S-propranolol across excised rat skin. The results from confocal laser scanning microscopy study, carried out with the R- and S-propranolol enantiomers labeled with a 1-pyrenebutyric acid probe as fluorescent markers, suggested that the MIP composite membrane selectively regulated the release of the recognised S-enantiomer via a facilitated transport pathway through complex formation with the selective receptor sites, while the release of the R-enantiomer was via a non-selective route. The reservoir patch for enantiomer-controlled delivery of propranolol was therefore fabricated by incorporating the chitosan gel formulation containing racemic propranolol hydrochloride into the MIP composite membrane laminated backing. These patch devices were shown to exhibit the significant stereoselectivity uptake of propranolol when attached to the skin, using pharmacokinetic studies in rats. S-Propranolol enantiomer plasma concentration profiles for the transdermal patch in the in vivo study were comparable to data for the gel formulations that were applied directly to skin, and containing a single S-enantiomer of propranolol. The results demonstrate that the transdermal patch based on the MIP composite membrane-controlled release system may have potential in the enantioselective-controlled delivery of the S-isomer of racemic propranolol.

The aim of the study is to examine thermal behavior of water within reticulated structure of bacterial cellulose (BC) films by sub-ambient differential scanning calorimetry (DSC). BC films with different carbon source, either manitol (BC (a)) or glycerol (BC (b)), were produced by Acetobacter xylinum using Hestrin and Shramm culture medium under static condition at 30 +/- 0.2 degrees C for 3 days. BC samples were characterized by electron scanning microscopy and X-ray diffraction spectroscopy. The pore analysis was done by B.H.J. nitrogen adsorption. The pre-treated with 100% relative humidity, at 30.0 +/- 0.2 degrees C for 7 days samples were subjected to a between 25 and -150 degrees C-cooling-heating cycle of DSC at 5.00 degrees C/min rate. The pre-treated samples were also hydrated by adding 1 mul of water and thermally run with identical conditions. It is observed that cellulose fibrils of BC (a) were thinner and reticulated to form slightly smaller porosity than those of BC (b). They exhibited slightly but non-significantly different crystalline features. The freezable bound water behaved as a water confinement within pores rather than a solvent of polymer which is possible to use thermoporosimetry based on Gibb-Thomson equation to approach pore structure of BC. In comparison with nitrogen adsorption, it was found that thermoporosimetry underestimated the BC porosity, i.e., the mean diameters of 23.0 nm vs. 27.8 nm and 27.9 nm vs. 33.9 nm for BC (a) and BC (b), respectively, by thermoporosimetry vs. B.H.J. nitrogen adsorption. It may be due to large non-freezable water fraction interacting with cellulose, and the validity of pore range based on thermodynamic assumptions of Gibb-Thomson theory.

Porphyromonas gingivalis infections cause problems in periodontal diseases and in certain systemic diseases. There is evidence that Lactobacillus spp. can control populations of P. gingivalis, but there are few data on the effects of purified bacteriocins from Lactobacillus paracasei HL32 on P. gingivalis. The objective of this study was to examine the antibacterial activity of a bacteriocin from L. paracasei HL32 and to relate this activity to its composition. A bacteriocin was purified from culture supernatants of Lactobacillus spp. using a dialysis technique followed by gel-permeation chromatography. Composition of the bacteriocin was characterised by ninhydrin tests, ultraviolet spectrophotometry, thin-layer chromatography, sodium-dodecyl sulphate-polyacrylamide gel electrophoresis, electrospray ionisation mass spectrometry and amino acid analysis. The amino acid sequence from the N-terminal of the bacteriocin was determined. Antibacterial activity was examined by the cylinder plate method, microtitre assay and scanning electron microscopy as compared with standard antibiotics. The bacteriocin had a molecular weight of approximately 56kDa, was comprised of 68% carbohydrate and 32% protein, and showed maximum peak absorbance at 214 and 254nm. The bacteriocin was found to be effective against P. gingivalis; it caused swelling and pore formation on the cell envelope at a minimum bactericidal concentration of 0.14mM, and caused death within 2h. Metronidazole killed P. gingivalis but did not affect the envelope, whereas tetracycline affected P. gingivalis with cell deformation. In conclusion, the bacteriocin from L. paracasei HL32 had the ability to kill P. gingivalis, suggesting that it could be a promising alternative chemotherapeutic agent for P. gingivalis infections.

A composite membrane for transdermal delivery of S-propranolol enantiomer was developed based on the controlled pore functionalization of bacterial cellulose membranes using a molecularly imprinted polymer (MIP) layer synthesis. The reactive pore-filling of an asymmetric porous cellulose membrane with a MIP thin-layer was effected using a silanized coupler as an additional anchor for the MIP. MIP thin-layers with specific binding sites for S-propranolol were synthesized by copolymerization of methacrylic acid with a cross-linker, ethylene glycol dimethacrylate in the presence of S-propranolol as the template molecule and the latter was subsequently extracted. Selective transport of S-propranolol through the MIP composite membrane was obtained, although this was determined mostly by the parent cellulose membrane with some ancillary contributory effect from the MIP layer. In addition, an enantioselectivity in the transport of propranolol prodrug enantiomers was found, suggesting that the shape and functional groups orientation, which are similar to that of the print molecule were essential for enantiomeric recognition of the MIP composite membrane. The enantioselectivity of S-MIP membranes was also shown when the release of propranolol enantiomers was studied in vitro using rat skin, with racemic propranolol contained in the donor compartment. The composite membrane of bacterially-derived cellulose and molecularly imprinted polymer may have great potential for use as a transdermal enantioselective controlled-release system for racemic propranolol.

The objective of this study was to develop a rapid-release diazepam suppository. Four kinds of diazepam suppositories were formulated: (1) a conventional suppository with Witepsol H-15 as a base, (2) a conventional suppository with mixed polyethylene glycols as a base, (3) a hollow-type suppository with Witepsol H-15 as a base that contained diazepam solution in its cavity and (4) a hollow-type suppository with Witepsol H-15 as a base that contained diazepam powder in its cavity. The result of the differential scanning calorimetry thermograms indicated that diazepam dissolved in Witepsol base had a strong affinity to the lipophiic base while diazepam dispersed in polyethylene glycol base was still in the crystalline form. The release study of prepared suppositories showed that the release of diazepam from suppository 1 and suppository 4 was very slow. The diazepam released from suppository 2 after 5 minutes was about 30%. The diazepam released from suppository 3 after 5 minutes was about 85%, which was significantly faster than that of the other three formulations (1, 2, and 4). The hollow-type suppository that contained diazepam solution was found to be the most effective rapid-release formulation.

Purpose: Prodrug of non-steroidal anti-inflammatory drugs (NSAIDs) or NSAIDs linked with guaiacol have been reported to suppress gastrointestinal (GI) toxicity or induce GI protective effect. In this study. mefenamic-guaiacol ester was synthesized and its physicochemical properties. stability, and transport across Caco-2 monolayers were investigated., Methods: Synthesis of the ester was carried out using mefenamic acid, guaiacol. N. N'-dimethylaminopyridine, and N,N'dicyclohexylcarbodiimide. The hydrolysis of the ester was investigated in aqueous buffer solutions pH 1-12 as well as in Caco-2 homogenate, human plasma, and porcine liver esterase. Caco-2 cell monolayers were utilized for transport studies. Due to the high lipophilicity of the ester with a calculated logP of 6.15, bovine serum albumin (BSA, 4%) was included in the receiver compartment to obtain a good in vitro-in vivo correlation. Permeation of the ester was assessed with or without the exposure of cells to PMSF, an inhibitor of esterase., Results: The ester was stable at a wide pH range from 1-10. However, it was hydrolyzed by enzymes from porcine liver esterase and Caco-2 homogenate. With the PMSF exposure on the apical (AP) side and in the presence of 4% BSA on the basolateral (BL) side, the transported amount of the ester from AP-to-BL direction was 14.63% after 3 hr with a lag time of 23 min. The Papp for the ester was 4.72 x 10(-6) cm s(-1)., Conclusion: The results from hydrolysis studies indicate that this ester is a prodrug. The Papp value suggests the moderate absorption characteristic of the compound. The accumulation of this highly lipophilic ester in Caco-2 cells is reduced in the presence of BSA.