Enhanced Solubility and Bioavailability of Naringenin via Liposomal Nanoformulation: Preparation and <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> Evaluations

This study was aimed at preparing orally administered naringenin-loaded liposome for pharmacokinetic and tissue distribution studies in animal models. The liposomal system, consisting of phospholipid, cholesterol, sodium cholate, and isopropyl myristate, was prepared using the thin-film hydration method. Physicochemical characterization of naringenin-loaded liposome such as particle size, zeta potential, and encapsulation efficiency produced 70.53?±?1.71 nm, ?37.4?±?7.3 mV, and 72.2?±?0.8%, respectively. The in vitro release profile of naringenin from the formulation in three different media (HCl solution, pH 1.2; acetate buffer solution, pH 4.5; phosphate buffer solution, pH 6.8) was significantly higher than the free drug. The in vivo studies also revealed an increase in AUC of the naringenin-loaded liposome from 16648.48 to 223754.0 ng·mL^?1 h as compared with the free naringenin. Thus, approximately 13.44-fold increase in relative bioavailability was observed in mice after oral administration. The tissue distribution further showed that the formulation was very predominant in the liver. These findings therefore indicated that the liposomal formulation significantly improved the solubility and oral bioavailability of naringenin, thus leading to wider clinical applications.     

<Emphasis Type="Italic">In Vitro</Emphasis> Anti-inflammatory and Antimicrobial Activities of Azithromycin After Loaded in Chitosan- and Tween 20-Based Oil-in-Water Macroemulsion for Acne Management

The objectives of the current investigation are (1) to prepare and characterize (particle size, surface charge (potential zeta), surface morphology by transmission electron microscopy, drug content, and drug release) the azithromycin (AZM, 100 mg)-loaded oil-in-water (o/w) macroemulsion, (2) to assess the toxicity of macroemulsion with or without AZM using RBC lysis test in comparison with AZM in phosphate buffer solution of pH 7.4, (3) to compare the in vitro antimicrobial activity (in Escherichia coli using zone inhibition assay) of AZM-loaded macroemulsion with its aqueous solution, and (4) to assess the in vitro anti-inflammatory effect (using egg albumin denaturation bioassay) of the AZM-loaded macroemulsion in comparison with diclofenac sodium in phosphate buffer solution of pH 7.4. The AZM-loaded macroemulsion possessed the dispersed oil droplets with a mean diameter value of 52.40?±?1.55 μm. A reversal in the zeta potential value from negative (?2.16?±?0.75 mV) to positive (+6.52?±?0.96 mV) was noticed when AZM was added into the macroemulsion. At a 1:5 dilution ratio, 2.06?±?0.03 mg of drug was released from macroemulsion followed by 1.01?±?0.01 and 0.25?±?0.08 mg, respectively, for 1:10 and 1:40 dilution ratios. Antimicrobial activity maintenance and significant reduction of RBC lysis property were noticed for AZM after loaded in the macroemulsion. However, an increment in the absorbance values for emulsion-treated samples in comparison to the control samples was noticed in the anti-inflammatory test. This speculates the potential of the AZM-loaded emulsion to manage inflammatory conditions produced at Acne vulgaris.     

Formulation,Optimization, Characterization,and Pharmacokinetics of Progesterone Intravenous Lipid Emulsion for Traumatic Brain Injury Therapy

Traumatic brain injury (TBI) is a major cause of mortality and disability throughout the world. Progesterone (PROG) plays an important role in neurologic treatment. The aim of this study was to develop a progesterone formulation with good physical and chemical stability. Progesterone intravenous lipid emulsion (PILE) was prepared based on one-factor-at-a-time experiments and orthogonal design. The optimal PILE was evaluated for mean particle size, particle size distribution, zeta potential, morphology, pH, osmolarity, entrapment efficiency, storage stability, and pharmacokinetics in ICR mice compared with the commercial progesterone products. The droplets of PILE had the smallest possible diameters of 218.0?±?1.8 nm and adequate zeta potential of ?41.1?±?0.9 mV. The volume percentage of droplets exceeding 5 μm (PFAT₅) of PILE was 0.003?±?0.0015% and much less than the specified standard. The TEM imaging proved that emulsion droplets had a smooth spherical appearance. Chemically and physically stable PILE was obtained with excellent entrapment efficiency that was up to 95.23%, with suitable pH at 7.15?±?0.01 and osmolarity at 301.3?±?1.2 mOsmol/l. Storage stability tests indicated that the emulsion was stable long term under ambient temperature conditions. Animal studies demonstrated that the emulsion was more effective with the higher progesterone concentration in the brain compared with commercial products. Therefore, the optimized PILE would offer great promise as a means of progesterone delivery for TBI therapy.     

Mercury sensing and toxicity studies of novel latex fabricated silver nanoparticles

Safe and eco-friendly alternatives to currently used hazardous chemico-physical methods of silver nanoparticles (AgNPs) synthesis are need of time. Rapid, low cost, selective detection of toxic metals in environmental sample is important to take safety action. Toxicity assessment of engineered AgNPs is essential to avoid its side effects on human and non-target organisms. In the present study, biologically active latex from Euphorbia heterophylla (Poinsettia) was utilized for synthesis of AgNPs. AgNPs was of spherical shape and narrow size range (20–50 nm). Occurrence of elemental silver and crystalline nature of AgNPs was analyzed. Role of latex metabolites in reduction and stabilization of AgNPs was analyzed by FT-IR, protein coagulation test and phytochemical analysis. Latex-synthesized AgNPs showed potential in selective and sensitive detection of toxic mercury ions (Hg²⁺) with limit of detection around 100 ppb. Addition of Hg²⁺ showed marked deviation in color and surface plasmon resonance spectra of AgNPs. Toxicity studies on aquatic non-target species Daphnia magna showed that latex-synthesized AgNPs (20.66 ± 1.52 % immobilization) were comparatively very less toxic than chemically synthesized AgNPs (51.66 ± 1.52 % immobilization). Similarly, comparative toxicity study on human red blood cells showed lower hemolysis (4.46 ± 0.01 %) by latex-synthesized AgNPs as compared to chemically synthesized AgNPs causing 6.14 ± 0.01 % hemolysis.     

Optimization of <Emphasis Type="Italic">Curcuma</Emphasis> Oil/Quinine-Loaded Nanocapsules for Malaria Treatment

Quinine, a treatment used in chloroquine-resistant falciparum malaria, was loaded into poly(?-caprolactone) or Eudragit^® RS100 nanocapsules using Curcuma oil as the oil-based core. Until now, the effect of cationic nanocapsules on malaria has not been reported. A 2⁴ factorial design was adopted using, as independent variables, the concentration of Curcuma oil, presence of quinine, type of polymer, and aqueous surfactant. Diameter, zeta potential, and pH were the responses studied. The formulations were also evaluated for drug content, encapsulation efficiency, photostability, and antimalarial activity against Plasmodium berghei-infected mice. The type of polymer influenced all of the responses studied. Quinine-loaded Eudragit^® RS100 (F13) and PCL nanocapsules (F9), both with polysorbate 80 coating, showed nanometric particle size, positive zeta potential, neutral pH, high drug content, and quinine photoprotection ability; thus, these nanocapsules were selected for in vivo tests. Both formulations showed lower levels of parasitemia from the beginning of the experiment (5.78 ± 3.60 and 4.76 ± 3.46% for F9 and F13, respectively) and highest survival mean time (15.3 ± 2.0 and 14.9 ± 5.6 days for F9 and F13, respectively). F9 and F13 showed significant survival curve compared to saline, thus demonstrating that nanoencapsulation improved bioefficacy of QN and co-encapsulated curcuminoids, regardless of the surface charge.     

Enhancement of Bioavailability and Pharmacodynamic Effects of Thymoquinone Via Nanostructured Lipid Carrier (NLC) Formulation

Thymoquinone (TQ), obtained from black cumin (Nigella sativa), is a natural product with anti-oxidant, anti-inflammatory, and hepatoprotective effects but unfortunately with poor bioavailability. Aiming to improve its poor oral bioavailability, TQ-loaded nanostructured lipid carriers (NLCs) were prepared by high-speed homogenization followed by ultrasonication and evaluated in vitro. Bioavailability and pharmacodynamic studies were also performed. The resultant NLCs showed poor physical homogeneity in Compritol 888 ATO Pluronic F127 system which consequently produced larger particle size and polydispersity index, smaller zeta potential values, and lower short-term (30 days) physical stability than other systems. Encapsulation efficiency percentage (EE%) lied between 84.6?±?5% and 96.2?±?1.6%. TQ AUC_0–t values were higher in animals treated with NLCs, with a relative bioavailability of 2.03- and 3.97-fold (for F9 and F12, respectively) higher than TQ suspension, indicating bioavailability enhancement by NLC formulation. Hepatoprotective effects of F12 showed significant (P?<?0.05) decrease in both serum alanine amino transferase and aspartate amino transferase to reach 305.0?±?24.88 and 304.7?±?23.55 U/ml, respectively, when compared with untreated toxic group. Anti-oxidant efficacy of F12 showed significant (P?<?0.05) decline of malondialdehyde and elevation of reduced glutatione. This improvement was also confirmed histopathologically.     

Structural and functional characterization of 4-hydroxyphenylpyruvate dioxygenase from the thermoacidophilic archaeon Picrophilus torridus

4-Hydroxyphenylpyruvate dioxygenase (Hpd, EC 1.13.11.27) catalyzes the conversion of 4-hydroxyphenylpyruvate into homogentisate in the second step of oxidative tyrosine catabolism. This pathway is known from bacteria and eukaryotes, but so far no archaeal Hpd has been described. Here, we report the biochemical characterization of an Hpd from the extremophilic archaeon Picrophilus torridus (Pt_Hpd), together with its three-dimensional structure at a resolution of 2.6 Å. Two pH optima were observed at 50 °C: pH 4.0 (close to native conditions) and pH 7.0. The enzyme showed only moderate thermostability and was inactivated with a half-life of ~1.5 h even under optimal reaction conditions. At the ideal physiological growth conditions of P. torridus, Pt_Hpd was inactive after 1 h, showing that the enzyme is protected in vivo from denaturation and/or is only partially adapted to the harsh environmental conditions in the cytosol of P. torridus. The influence of different additives on the activity was investigated. Pt_Hpd exhibited a turnover number k _cat of 9.9 ± 0.6 s^?1 and a substrate binding affinity K _m of 142 ± 23 µM. In addition, substrate inhibition with a binding affinity K _i of 1.9 ± 0.3 mM was observed. Pt_Hpd is compared with isoenzymes from other species and the putative bacterial origin of the gene is discussed.     

Degradation of a xenobiotic textile dye, Disperse Brown 118, by Brevibacillus laterosporus

The toxic textile dye, Disperse Brown 118, was degraded by Brevibacillus laterosporus. 96 % decolorization was achieved within 48 h at pH 7, 40 °C at 50 mg dye l^?1 accompanied by significant increases in the activities of veratryl alcohol oxidase, tyrosinase and NADH-DCIP reductase. HPTLC and FT-IR spectroscopy confirmed biodegradation after dye decolorization. As identified by GC–MS, biodegradation products of Disperse Brown 118 were N-carbamoyl-2-[(8-chloroquinazolin-4-yl)oxy] acetamide and N-carbamoyl-2-(quinazolin-4-yloxy)acetamide which were much less toxic than parent dye as evidenced by phytotoxicity tests.     

Purification, characterization and cloning of a thermotolerant isoamylase produced from Bacillus sp. CICIM 304

A novel thermostable isoamylase, IAM, was purified to homogeneity from the newly isolated thermophilic bacterium Bacillus sp. CICIM 304. The purified monomeric protein with an estimated molecular mass of 100 kDa displayed its optimal temperature and pH at 70 °C and 6.0, respectively, with excellent thermostability between 30 and 70 °C and pH values from 5.5 to 9.0. Under the conditions of temperature 50 °C and pH 6.0, the K _m and V _max on glycogen were 0.403 ± 0.018 mg/mg and 0.018 ± 0.001 mg/(min mg), respectively. Gene encoding IAM, BsIam was identified from genomic DNA sequence with inverse PCRs. The open reading frame of the BsIam gene was 2,655 base pairs long and encoded a polypeptide of 885 amino acids with a calculated molecular mass of 101,155 Da. The deduced amino acid sequence of IAM shared less than 40 % homology with that of microbial isoamylase ever reported, which indicated it was a novel isoamylase. This enzyme showed its obvious superiority in the industrial starch conversion process.     

In vivo and in vitro decolorization of synthetic dyes by laccase from solid state fermentation with Trametes sp. SYBC-L4

Synthetic decolorization of dyes through solid cassava residue substrate fermentation with Trametes sp. SYBC-L4 via in vivo and in vitro processes was investigated in this study. Effects of pH and mediator (1-hydroxybenzotriazole, HBT) concentration on dyes decolorization were evaluated. In vitro, decolorization ratios of dyes differed considerably in pH and increased with the increasing of HBT concentration. Crude laccase (50 U/L) derived from Trametes sp. SYBC-L4 decolorized 67.91 ± 1.25 % Congo red (100 mg/L), 94.58 ± 1.05 % aniline blue (100 mg/L) and 99.02 ± 0.54 % indigo carmine (100 mg/L) with 2.5 mM HBT at pH 4.5 in 36 h of incubation. In vivo, decolorization ratios of dyes were not enhanced by usage of the mediator. After 10 days of fermentation, decolorization ratio of Congo red (1,000 mg/kg), aniline blue (1,000 mg/kg) and indigo carmine (1,000 mg/kg) was 57.82 ± 0.84, 92.53 ± 1.12 and 97.26 ± 1.92 % without the usage of mediator at pH 4.5, respectively. Moreover, there was no obvious difference between the in vivo decolorization of aniline blue and indigo carmine in the pH range of 3.0–9.0. Results showed that Trametes sp. SYBC-L4 had great potential to be used for dyes decolorization via in vivo and in vitro processes. Moreover, in terms of pH range and mediator, in vivo decolorization with Trametes sp. SYBC-L4 was more advantageous since laccase mediator was needless and the applicable range of pH was broader.     

Spectral CT Imaging in Patients with Budd-Chiari Syndrome: Investigation of Image Quality

To assess the image quality of monochromatic imaging from spectral CT in patients with Budd-Chiari syndrome (BCS), fifty patients with BCS underwent spectral CT to generate conventional 140 kVp polychromatic images (group A) and monochromatic images, with energy levels from 40 to 80, 40 + 70, and 50 + 70 keV fusion images (group B) during the portal venous phase (PVP) and the hepatic venous phase (HVP). Two-sample t tests compared vessel-to-liver contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) for the portal vein (PV), hepatic vein (HV), inferior vena cava. Readers’ subjective evaluations of the image quality were recorded. The highest SNR values in group B were distributed at 50 keV; the highest CNR values in group B were distributed at 40 keV. The higher CNR values and SNR values were obtained though PVP of PV (SNR 18.39 ± 6.13 vs. 10.56 ± 3.31, CNR 7.81 ± 3.40 vs. 3.58 ± 1.31) and HVP of HV (3.89 ± 2.08 vs. 1.27 ± 1.55) in the group B; the lower image noise for group B was at 70 keV and 50 + 70 keV (15.54 ± 8.39 vs. 18.40 ± 4.97, P = 0.0004 and 18.97 ± 7.61 vs. 18.40 ± 4.97, P = 0.0691); the results show that the 50 + 70 keV fusion image quality was better than that in group A. Monochromatic energy levels of 40–70, 40 + 70, and 50 + 70 keV fusion image can increase vascular contrast and that will be helpful for the diagnosis of BCS, we select the 50 + 70 keV fusion image to acquire the best BCS images.     

Anaerobic fungal communities differ along the horse digestive tract

Anaerobic fungi are potent fibre degrading microbes in the equine hindgut, yet our understanding of their diversity and community structure is limited to date. In this preliminary work, using a clone library approach we studied the diversity of anaerobic fungi along six segments of the horse hindgut: caecum, right ventral colon (RVC), left ventral colon (LVC), left dorsal colon (LDC), right dorsal colon (RDC) and rectum. Of the 647 ITS1 clones, 61.7 % were assigned to genus level groups that are so far without any cultured representatives, and 38.0 % were assigned to the cultivated genera Neocallimastix (35.1 %), Orpinomyces (2.3 %), and Anaeromyces (0.6 %). AL1 dominated the group of uncultured anaerobic fungi, particularly in the RVC (88 %) and LDC (97 %). Sequences from the LSU clone library analysis of the LDC, however, split into two distinct phylogenetic clusters with low sequence identity to Caecomyces sp. (94–96 %) and Liebetanzomyces sp. (92 %) respectively. Sequences belonging to cultured Neocallimastix spp. dominated in LVC (81 %) and rectum (75.5 %). Quantification of anaerobic fungi showed significantly higher concentrations in RVC and RDC compared to other segments, which influenced the interpretation of the changes in anaerobic fungal diversity along the horse hindgut. These preliminary findings require further investigation.     

Triphenylphosphonium-desferrioxamine as a candidate mitochondrial iron chelator

Cell-impermeant iron chelator desferrioxamine (DFO) can have access to organelles if appended to suitable vectors. Mitochondria are important targets for the treatment of iron overload-related neurodegenerative diseases. Triphenylphosphonium (TPP) is a delocalized lipophilic cation used to ferry molecules to mitochondria. Here we report the synthesis and characterization of the conjugate TPP–DFO as a mitochondrial iron chelator. TPP–DFO maintained both a high affinity for iron and the antioxidant activity when compared to parent DFO. TPP–DFO was less toxic than TPP alone to A2780 cells (IC₅₀ = 135.60 ± 1.08 and 4.34 ± 1.06 μmol L^?1, respectively) and its native fluorescence was used to assess its mitochondrial localization (Rr = +0.56). These results suggest that TPP–DFO could be an interesting alternative for the treatment of mitochondrial iron overload e.g. in Friedreich’s ataxia.     

Acute Toxicity of Arsenic under Different Temperatures and Salinity Conditions on the White Shrimp Litopenaeus vannamei

The aim of this study was to determine acute toxicity in the post larvae of the white shrimp Litopenaeus vannamei after 96 h of exposure to dissolved arsenic under three different temperatures and salinity conditions. Recent reports have shown an increase in the presence of this metalloid in coastal waters, estuaries, and lagoons along the Mexican coast. The white shrimp stands out for its adaptability to temperature and salinity changes and for being the main product for many commercial fisheries; it has the highest volume of oceanic capture and production in Mexican shrimp farms. Lethal concentrations (LC₅₀–96 h) were obtained at nine different combinations (3?×?3 combinations in total) of temperature (20, 25, and 30 °C) and salinity (17, 25, and 33) showing mean LC₅₀–96 h values (±standard error) of 9.13?±?0.76, 9.17?±?0.56, and 6.23?±?0.57 mgAs?L^?1(at 20 °C and 17, 25, and 33 salinity); 12.29?±?2.09, 8.70?±?0.82, and 8.03?±?0.59 mgAs?L^?1 (at 25 °C and 17, 25, and 33 salinity); and 7.84?±?1.30, 8.49?±?1.40, and 7.54?±?0.51 mgAs?L^?1 (at 30 °C and 17, 25, and 33 salinity), respectively. No significant differences were observed for the optimal temperature and isosmotic point of maintenance (25 °C–S 25) for the species, with respect to the other experimental conditions tested, except for at 20 °C–S 33, which was the most toxic. Toxicity under 20 °C–S 33 conditions was also higher than 25 °C–S 17 and 20 °C (S 17 or 25). The least toxic condition was 25 °C–S 17. All this suggests that the toxic effect of arsenic is not affected by temperature changes; it depends on the osmoregulatory pattern developed by the shrimp, either hyperosmotic at low salinity or hiposmotic at high salinity, as observed at least on the extreme salinity conditions here tested (17 and 33). However, further studies testing salinities near the isosmotic point (between 20 and 30 salinities) are needed to clarify these mechanisms.     

Induction of laccases in Trametes versicolor by aqueous wood extracts

The induction of laccase isoforms in Trametes versicolor HEMIM-9 by aqueous extracts (AE) from softwood and hardwood was studied. Samples of sawdust of Pinus sp., Cedrela sp., and Quercus sp. were boiled in water to obtain AE. Different volumes of each AE were added to fungal cultures to determine the amount of AE needed for the induction experiments. Laccase activity was assayed every 24 h for 15 days. The addition of each AE (50 to 150 μl) to the fungal cultures increased laccase production compared to the control (0.42 ± 0.01 U ml^?1). The highest laccase activities detected were 1.92 ± 0.15 U ml^?1 (pine), 1.87 ± 0.26 U ml^?1 (cedar), and 1.56 ± 0.34 U ml^?1 (oak); laccase productivities were also significantly increased. Larger volumes of any AE inhibited mycelial growth. Electrophoretic analysis revealed two laccase bands (lcc1 and lcc2) for all the treatments. However, when lcc2 was analyzed by isoelectric focusing, inducer-dependent isoform patterns composed of three (pine AE), four (oak AE), and six laccase bands (cedar AE) were observed. Thus, AE from softwood and hardwood had induction effects in T. versicolor HEMIM-9, as indicated by the increase in laccase activity and different isoform patterns. All of the enzymatic extracts were able to decolorize the dye Orange II. Dye decolorization was mainly influenced by pH. The optimum pH for decolorization was pH 5 (85 %), followed by pH 7 (50 %) and pH 3 (15 %). No significant differences in the dye decolorizing capacity were detected between the control and the differentially induced laccase extracts (oak, pine and cedar). This could be due to the catalytic activities of isoforms with pI 5.4 and 5.8, which were detected under all induction conditions.     

Inorganic carbon and pH effect on growth and lipid productivity of Tetraselmis suecica and Chlorella sp (Chlorophyta) grown outdoors in bag photobioreactors

There has been considerable interest in cultivation of green microalgae (Chlorophyta) as a source of lipid that can alternatively be converted to biodiesel. However, almost all mass cultures of algae are carbon-limited. Therefore, to reach a high biomass and oil productivities, the ideal selected microalgae will most likely need a source of inorganic carbon. Here, growth and lipid productivities of Tetraselmis suecica CS-187 and Chlorella sp were tested under various ranges of pH and different sources of inorganic carbon (untreated flue gas from coal-fired power plant, pure industrial CO₂, pH-adjusted using HCl and sodium bicarbonate). Biomass and lipid productivities were highest at pH 7.5 (320?±?29.9 mg biomass L^?1 day^?1and 92?±?13.1 mg lipid L^?1 day^?1) and pH 7 (407?±?5.5 mg biomass L^?1 day^?1 and 99?±?17.2 mg lipid L^?1 day^?1) for T. suecica CS-187 and Chlorella sp, respectively. In general, biomass and lipid productivities were pH 7.5?>?pH 7?>?pH 8?>?pH 6.5 and pH 7?>?pH 7.5?=?pH 8?>?pH 6.5?>?pH 6?>?pH 5.5 for T. suecica CS-187 and Chlorella sp, respectively. The effect of various inorganic carbon on growth and productivities of T. suecica (regulated at pH?=?7.5) and Chlorella sp (regulated at pH?=?7) grown in bag photobioreactors was also examined outdoor at the International Power Hazelwood, Gippsland, Victoria, Australia. The highest biomass and lipid productivities of T. suecica (51.45?±?2.67 mg biomass L^?1 day^?1 and 14.8?±?2.46 mg lipid L^?1 day^?1) and Chlorella sp (60.00?±?2.4 mg biomass L^?1 day^?1 and 13.70?±?1.35 mg lipid L^?1 day^?1) were achieved when grown using CO₂ as inorganic carbon source. No significant differences were found between CO₂ and flue gas biomass and lipid productivities. While grown using CO₂ and flue gas, biomass productivities were 10, 13 and 18 %, and 7, 14 and 19 % higher than NaHCO₃, HCl and unregulated pH for T. suecica and Chlorella sp, respectively. Addition of inorganic carbon increased specific growth rate and lipid content but reduced biomass yield and cell weight of T. suecica. Addition of inorganic carbon increased yield but did not change specific growth rate, cell weight or content of the cell weight of Chlorella sp. Both strains showed significantly higher maximum quantum yield (F_v/F_m) when grown under optimum pH.     

A Highly Efficient NADH-dependent Butanol Dehydrogenase from High-butanol-producing Clostridium sp. BOH3

Butanol has been considered as a better alternative fuel and it can be produced from anaerobic Clostridial fermentation. Though several enzymes are involved in the biosynthesis of butanol in Clostridia, butanol dehydrogenase (BDH) is understood to play a major role, which catalyzes the conversion of butyraldehyde into butanol at the expenditure of a cofactor NAD(P)H. Recently, the strain Clostridium sp. BOH3 is reported to generate high level of butanol from monosugars. To investigate the BDH activity at various stages of fermentation, BOH3 was cultured in reinforced Clostridial medium with 30 g/l of glucose at 35 °C and the cells were harvested periodically from acid production and solvent production phases. During acid production, NADPH-dependent BDH activity is higher than NADH dependent BDH. Conversely, NADH-BDH activity is predominant during solvent production phase. The optimum pHs for NADH and NADPH-BDH are estimated as pH?6 and 8, respectively. By employing three steps of purification, NADH-BDH is purified to 102-fold with 36 % yield. Subsequent characterization reveals that NADH-BDH is a dimer composed of two subunits depicting the molecular weight of 44 kDa. The peptide finger printing analysis (MS/MS) suggests that the purified protein has higher homology with bifunctional acetaldehyde-CoA and alcohol dehydrogenase of Clostridium acetobutylicum. The extensive kinetic studies show that NADH-BDH follows an ordered sequential bi bi mechanism. The calculated values of K _{butyraldehyde} and K _NADH are 8.35?±?0.25 and 0.076?±?0.02 mM, respectively, whereas V _max is 4.02?±?0.07 μmol/(mg protein. min). The purified NADH-BDH retains 70 % of its initial activity after 7 days at 4 °C.     

Topical Formulation Containing Beeswax-Based Nanoparticles Improved <Emphasis Type="Italic">In Vivo</Emphasis> Skin Barrier Function

Lipid nanoparticles have shown many advantages for treatment/prevention of skin disorders with damaged skin barrier function. Beeswax is a favorable candidate for the development of nanosystems in the cosmetic and dermatological fields because of its advantages for the development of products for topical application. In the present study, beeswax-based nanoparticles (BNs) were prepared using the hot melt microemulsion technique and incorporated to a gel-cream formulation. The formulation was subsequently evaluated for its rheological stability and effect on stratum corneum water content (SCWC) and transepidermal water loss (TEWL) using in vivo biophysical techniques. BNs resulted in mean particle size of 95.72?±?9.63 nm and zeta potential of ?9.85?±?0.57 mV. BN-loaded formulation showed shear thinning behavior, well adjusted by the Herschel-Bulkley model, and a small thixotropy index that were stable for 28 days at different temperatures. BN-loaded formulation was also able to simultaneously decrease the TEWL and increase the SCWC values 28 days after treatment. In conclusion, the novel beeswax-based nanoparticles showed potential for barrier recovery and open the perspective for its commercial use as a novel natural active as yet unexplored in the field of dermatology and cosmetics for treatment of skin diseases with damaged skin barrier function.     

Mucoadhesive Chitosan-Pectinate Nanoparticles for the Delivery of Curcumin to the Colon

In the present study, we report the properties of a mucoadhesive chitosan-pectinate nanoparticulate formulation able to retain its integrity in the milieu of the upper gastrointestinal tract and subsequently, mucoadhere and release curcumin in colon conditions. Using this system, we aimed to deliver curcumin to the colon for the possible management of colorectal cancer. The delivery system comprised of a chitosan-pectinate composite nanopolymeric with a z-average of 206.0 nm (±6.6 nm) and zeta potential of +32.8 mV (±0.5 mV) and encapsulation efficiency of 64%. The nanoparticles mucoadhesiveness was higher at alkaline pH compared to acidic pH. Furthermore, more than 80% release of curcumin was achieved in pectinase-enriched medium (pH 6.4) as opposed to negligible release in acidic and enzyme-restricted media at pH 6.8. SEM images of the nanoparticles after exposure to the various media indicate a retained matrix in acid media as opposed to a distorted/fragmented matrix in pectinase-enriched medium. The data strongly indicates that the system has the potential to be applied as a colon-targeted mucoadhesive curcumin delivery system for the possible treatment of colon cancer.     

Enhanced Solubility and Dissolution Rate of Lacidipine Nanosuspension: Formulation Via Antisolvent Sonoprecipitation Technique and Optimization Using Box–Behnken Design

Lacidipine (LCDP) is a highly lipophilic calcium channel blocker of poor aqueous solubility leading to poor oral absorption. This study aims to prepare and optimize LCDP nanosuspensions using antisolvent sonoprecipitation technique to enhance the solubility and dissolution of LCDP. A three-factor, three-level Box–Behnken design was employed to optimize the formulation variables to obtain LCDP nanosuspension of small and uniform particle size. Formulation variables were as follows: stabilizer to drug ratio (A), sodium deoxycholate percentage (B), and sonication time (C). LCDP nanosuspensions were assessed for particle size, zeta potential, and polydispersity index. The formula with the highest desirability (0.969) was chosen as the optimized formula. The values of the formulation variables (A, B, and C) in the optimized nanosuspension were 1.5, 100%, and 8 min, respectively. Optimal LCDP nanosuspension had particle size (PS) of 273.21 nm, zeta potential (ZP) of ?32.68 mV and polydispersity index (PDI) of 0.098. LCDP nanosuspension was characterized using x-ray powder diffraction, differential scanning calorimetry, and transmission electron microscopy. LCDP nanosuspension showed saturation solubility 70 times that of raw LCDP in addition to significantly enhanced dissolution rate due to particle size reduction and decreased crystallinity. These results suggest that the optimized LCDP nanosuspension could be promising to improve oral absorption of LCDP.