Economic production of Lysinibacillus sphaericus under solid state fermentation

A highly active mosquitocidal Lysinibacillus sphaericus namely Ls 9B24 was isolated from soil of Alexandria governorate in Egypt. It was more active than the standard strain, L. sphaericus 2362. The sporulation and toxin formation of both cultures grown on different leguminous seeds and by-products under solid state fermentation (SSF) were studied. Among the tested substrates, 6% cotton seed meal enhanced sporulation and the mosquitocidal activity of L. sphaericus 2362, while 6% fodder yeast enhanced sporulation and the mosquitocidal activity of Ls 9B24. The optimum SSF growth conditions for maximum mosquitocidal activity by both cultures were using coarse wheat bran as a carrier material, 50% initial moisture content, 4–64 × 10⁶ colony forming units (CFU)/g solid medium inoculum and 6 days’ incubation period at 30°C. Addition of 0.5% yeast extract enhanced toxicity about 2.2 and 1.8 fold for L. sphaericus 2362 and Ls 9B24, respectively.     

Hesperidin modulates dextran sulfate sodium‐induced ulcerative colitis in rats: Targeting sphingosine kinase‐1‐ sphingosine 1 phosphate signaling pathway,mitochondrial biogenesis,inflammation, and apoptosis

Ulcerative colitis (UC) is a chronic gastrointestinal disorder interfering with life quality. A total of 60 male Wistar rats were divided into four equal groups: Control (group I), hesperidin only (group II), UC untreated (group III), and UC treated with hesperidin (group IV). Hesperidin had modulatory effects on UC pathogenesis, which might be through alleviating colonic sphingosine phosphate phosphatase 2 messenger RNA expression and sphingosine kinase‐1 levels, thus suppressing the subsequent downstream inflammatory and apoptotic cascades represented by decreased macrophage inflammatory protein‐1α and enhancement of B‐cell lymphoma 2 immunohistochemistry expression. Also, it improved mitochondrial biogenesis by increasing the peroxisome proliferator‐activated receptor‐gamma‐coactivator 1‐α level. It successfully restored redox potential as evidenced by marked alleviations of the nitric oxide and peroxynitrite levels, increasing total antioxidant capacity, and activating the superoxide dismutase enzyme. Also, hesperidin alleviated the UC disease activity index and improved the histopathological picture. These findings may offer a new therapeutic strategy for UC treatment.     

Do cancer cells in human and meristematic cells in plant exhibit similar responses toward plant extracts with cytotoxic activities?

We examined the effect of water extracts of Persea americana fruit, and of the leaves of Tabernamontana divericata, Nerium oleander and Annona cherimolia (positive control) on Vicia faba root cells. We had confirmed in our previously published data the cytotoxicity of these plant extracts on four human cancer cell lines: liver (HepG-2), lung (A549), colon (HT-29) and breast (MCF-7). Vicia faba roots were soaked in plant extracts at dilutions of 100, 1,250, 2,500, 5,000, 10,000, 20,000 ppm for 4 and 24 h. All treatments resulted in a significant reduction in the mitotic index in a dose dependant manner. Root cells treated with T. divericata, N. oleander and A. cherimolia exhibited a decrease in prophase cell percentage, increase in micronuclei and chromosomal abnormalities as concentration increased. The P. americana treatment showed the highest cytotoxic effect on cancer cells, prophase cell percentage increased linearly with the applied concentration and no micronuclei were detected. This study shows that root tip assay of beans can be used in initial screening for new plant extracts to validate their use as candidates for containing active cytotoxic agents against malignant cells. This will greatly help in exploring new plant extracts as drugs for cancer treatment.     

Extracts of Feijoa Inhibit Toll-Like Receptor 2 Signaling and Activate Autophagy Implicating a Role in Dietary Control of IBD

Background

Inflammatory bowel disease (IBD) is a heterogeneous chronic inflammatory disease affecting the gut with limited treatment success for its sufferers. This suggests the need for better understanding of the different subtypes of the disease as well as nutritional interventions to compliment current treatments. In this study we assess the ability of a hydrophilic feijoa fraction (F3) to modulate autophagy a process known to regulate inflammation, via TLR2 using IBD cell lines.

Method

Mouse embryonic fibroblasts (MEF) deleted for ATG5, and two intestinal epithelial cells HCT15 and HCT116, were used to test the anti-inflammatory effect of F3 after stimulating the cells with a TLR2 specific ligand PAM3CSK4.

Results

F3 was able to reduce TLR2 specific inflammation and stimulate autophagy in MEFs and HCT15 cells but not in HCT116 cells. The anti-inflammatory effect was reduced in the MEF cells deleted for ATG5. In addition, the activation of autophagy by F3 was enhanced by PAM3CSK4.

Conclusion

F3 of feijoa can interact with cells via a TLR2 specific mechanism and reduce Nuclear factor kappa B (NF-κB) activation in part due to stimulation of autophagy. These results suggest that there is potential benefit in using feijoa extracts as part of dietary interventions to manage IBD in patients.     

Basis for formulating biosurfactant mixtures to achieve ultra low interfacial tension values against hydrocarbons

Biosurfactants could potentially replace or be used in conjunction with synthetic surfactants to provide for more cost-effective subsurface remediation. The design of surfactant formulations that are effective in lowering interfacial tension (IFT), which is necessary to mobilize entrapped hydrocarbons, requires information about the surface-active agent (surfactant) and the targeted non-aqueous phase liquids (NAPL). We hypothesized that biosurfactant and synthetic surfactant mixtures can be formulated to provide the appropriate hydrophobic/hydrophilic conditions necessary to produce low IFT against NAPLs, and that such mixtures will produce synergism that make them more effective than individual biosurfactants or synthetic surfactants. Our work tested the interfacial activity of biosurfactants from individual strains and mixtures of biosurfactants from different strains with and without a synthetic surfactant. Multiple regression analysis showed that, for lipopeptide biosurfactants produced by various Bacillus species, the interfacial activity against toluene depended on the relative proportions of 3-OH-C₁₄, C₁₅, C₁₆, and C₁₈ in the fatty acid tail. As the fatty acid composition became more heterogeneous the system produced lower IFT against toluene. In mixtures of lipopeptide biosurfactants with the more hydrophilic, rhamnolipid biosurfactant, the IFT against toluene decreased as the percentage of the 3-OH C₁₄ fatty acid increased in the lipopeptide. Mixtures of lipopeptide biosurfactants with the more hydrophobic synthetic surfactant, C12, C13-8PO SO₄Na, were able to produce low IFT against hexane and decane. In general, we found that lipopeptide biosurfactants with a heterogeneous fatty acid composition or mixtures of lipopeptide and rhamnolipid biosurfactants lowered the IFT against hydrophilic NAPLs. Conversely, mixtures of lipopeptide biosurfactants with a more hydrophobic synthetic surfactant lowered the IFT against hydrophobic NAPLs.     

Polyacetylenes from Notopterygium incisum–New Selective Partial Agonists of Peroxisome Proliferator-Activated Receptor-Gamma

Peroxisome proliferator-activated receptor gamma (PPARγ) is a key regulator of glucose and lipid metabolism and therefore an important pharmacological target to combat metabolic diseases. Since the currently used full PPARγ agonists display serious side effects, identification of novel ligands, particularly partial agonists, is highly relevant. Searching for new active compounds, we investigated extracts of the underground parts of Notopterygium incisum, a medicinal plant used in traditional Chinese medicine, and observed significant PPARγ activation using a PPARγ-driven luciferase reporter model. Activity-guided fractionation of the dichloromethane extract led to the isolation of six polyacetylenes, which displayed properties of selective partial PPARγ agonists in the luciferase reporter model. Since PPARγ activation by this class of compounds has so far not been reported, we have chosen the prototypical polyacetylene falcarindiol for further investigation. The effect of falcarindiol (10 µM) in the luciferase reporter model was blocked upon co-treatment with the PPARγ antagonist T0070907 (1 µM). Falcarindiol bound to the purified human PPARγ receptor with a K_i of 3.07 µM. In silico docking studies suggested a binding mode within the ligand binding site, where hydrogen bonds to Cys285 and Glu295 are predicted to be formed in addition to extensive hydrophobic interactions. Furthermore, falcarindiol further induced 3T3-L1 preadipocyte differentiation and enhanced the insulin-induced glucose uptake in differentiated 3T3-L1 adipocytes confirming effectiveness in cell models with endogenous PPARγ expression. In conclusion, we identified falcarindiol-type polyacetylenes as a novel class of natural partial PPARγ agonists, having potential to be further explored as pharmaceutical leads or dietary supplements.     

Fluorimetric determination of febuxostat in dosage forms and in real human plasma via Förster resonance energy transfer

A rapid, simple, selective and precise fluorimetric method was developed and validated for determination of a selective xanthine oxidase inhibitor; febuxostat (FBX) in pharmaceutical formulations and in human plasma. The proposed method is based on quenching effect of FBX on the fluorescence intensity of terbium (Tb³⁺) through fluorescence resonance energy transfer (FRET) from Tb³⁺ to FBX. The formed complex was measured at λ_ex. 320 nm/λ_em. 490 nm against a reagent blank. Fluorescence intensity of Tb³⁺ was diminished when FBX was added. A linear relationship between the fluorescence quenching value of the formed complex and the concentration of FBX was investigated. The reaction conditions and the fluorescence spectral properties of the complex have been studied. The linearity range of the developed method was 1.0–16.0 μg/ml. The suggested method was applied successfully for the estimation of FBX in bulk powder, dosage forms and spiked plasma samples with excellent recoveries (96.79–98.89%). In addition, the developed method has been successfully applied for determination of FBX in real plasma samples collected from healthy volunteers with good recoveries (82.06–85.65%). All obtained results of the developed method were statistically analyzed and validated according to ICH (International Conference on Harmonization) guidelines.     

Male disadvantage? Fetal sex and cardiovascular responses to asphyxia in preterm fetal sheep

Clinically and experimentally male fetuses are at significantly greater risk of dying or suffering injury at birth, particularly after premature delivery. We undertook a retrospective cohort analysis of 60 female and 65 male singleton preterm fetal sheep (103-104 days, 0.7 gestation) with mean arterial blood pressure (MAP), heart rate, and carotid and femoral blood flow recordings during 25 min of umbilical cord occlusion in utero. Occlusions were stopped early if fetal MAP fell below 8 mmHg or if there was asystole for >20 s. Fetuses that were able to complete the full 25-min period of occlusion showed no differences between sexes for any cardiovascular responses. Similar numbers of occlusions were stopped early in males (mean: 21 min, n = 16) and females (mean: 23 min, n = 16); however, they showed different responses. Short-occlusion males (n = 16) showed a slower initial fall in femoral vascular conductance, followed by greater bradycardia, hypotension, and associated organ hypoperfusion compared with full-occlusion fetuses. In contrast, short-occlusion females (n = 16) showed a significantly more rapid early increase in femoral vascular conductance than the full-occlusion fetuses, followed by worsening of bradycardia and hypotension that was intermediate to the full-occlusion fetuses and short-occlusion males. Among all fetuses, MAP at 15 min of occlusion, corresponding with the time of the maximal rate of fall, was correlated with postmortem weight in males (R(2) = 0.07) but not females. In conclusion, male and female fetuses showed remarkably similar chemoreflex and hemodynamic responses to severe asphyxia, but some males did show impaired hemodynamic adaptation within the normal weight range.     

Origin and function of the multiple extracellular glucosyltransferase species from cultures of a serotype c strain of Streptococcus mutans

Two methods were used to purify the bifunctional extracellular enzyme sucrose: (1-6)- and (1-3)-alpha-D-glucan-6-alpha-D-glucosyltransferase (EC 2.4.1.5; dextransucrase) from continuous cultures of a serotype c strain of Streptococcus mutans. The first method, based on a previously published report, involved Sepharose 6B gel filtration and DEAE cellulose anion exchange chromatography. This resulted in a dextransucrase preparation with an apparent molecular mass of 162 kDa and a specific activity of 125 mg of glucan formed from sucrose h-1 (mg of protein)-1, at 37 degrees C. It was almost homogeneous as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The ratio of carbohydrate to protein was 0.14 and the recovery was 14% relative to the total glucosyltransferase activity in the original culture fluid. In the subsequently preferred method, hydroxyapatite-Ultrogel was used to purify dextransucrase with a 24% yield. The specific activity, 197 mg of glucan formed h-1 (mg of protein)-1, was the highest yet reported and this preparation contained less than 0.5 glucose-equivalent per subunit of molecular mass 162 kDa. Dextransucrase is therefore not a glycoprotein. Exogenous dextran stimulated activity, but was not essential for activity. The purified protein slowly degraded to multiple lower molecular mass forms during storage at 4 degrees C and 87% of the activity was lost after 20 days. The molecular mass of the most prominent, active degradation product was 140 kDa, similar to that of one of the multiple forms of dextransucrase detected in other laboratories. Preparations in which either the 140-kDa or the 162-kDa species predominated catalyzed the synthesis of a water-soluble glucan with sucrose alone, but catalyzed that of an insoluble glucan with sucrose and a high concentration of either (NH4)2SO4 or polyethylene glycol. The water-insoluble glucan was shown to lack sequences of 1,3-alpha-linked glycosyl residues typical of the insoluble glucan, mutan, which has been implicated in dental caries. We conclude that mutan is synthesized by the concerted action of two independent glucosyltransferases rather than by interconvertible forms of a single enzyme, as was proposed previously.     

Development of sensitive spectrofluorometric approach based on formation of pyrrolidone derivative for determination of linagliptin through condensation reaction with ninhydrin and phenylacetaldehyde: Application to content uniformity and real plasma

The new drug linagliptin belongs to the class of dipeptidyl peptidase-4 enzyme inhibitors. Linagliptin is used to treat type 2 diabetes and is taken orally either alone or in combination with other drugs. In this instance, a new, simple, and economical technique for analyzing linagliptin was developed by the effective use of a pyrrolidone derivative. The primary amine group of linagliptin permits its condensation with ninhydrin (0.14% w/v) to produce a fluorescent product in the presence of phenylacetaldehyde (0.02% v/v). All experimental parameters were carefully examined and adjusted in order to monitor the generation of the pyrrolidone derivative at excitation and emission wavelengths of 385 and 475 nm, respectively. The calibration graph was made by plotting the intensity of the fluorescence in relation to linagliptin concentration. A significant linearity was found for values ranging from 20 to 460 ng/mL. The process's validity has been verified by a thorough assessment of the instructions provided by the International Conference on Harmonization (ICH). The results indicate excellent uniformity with a reference method, showing that there is no substantial difference in precision and accuracy. The proposed approach was utilized for determining linagliptin in real rat plasma successfully owing to its high sensitivity. Additionally, the proposed approach was evaluated using the Eco-Scale evaluation tool and showed a high degree of eco-friendliness (86/100).