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Metal complexes of drug are used to inhibit growth of pathogenic microorganisms and reduces drug resistance. Moxifloxacin is a dihydroquinoline-3-carboxylic acid 4th generation fluoroquinolone antibiotic that has tendency to bind with metal ions. In current study four moxifloxacin-metal complexes i.e. Moxifloxacin-sliver (Moxi-Ag), Moxifloxacin-rhodium (Moxi-Rh), Moxifloxacin-titanium (Moxi-Ti) and Moxifloxacin-rubidium (Moxi-Rb) have been synthesized and evaluated for antibacterial activities against resistant microorganisms along with antioxidant effects. The structure elucidation was carried out using FTIR, 1H- NMR, and UV-Vis spectroscopy. Agar well diffusion method and DPPH (1, 1- dipheny1-2-picrylhydrazyl) methods were used to study the antibacterial and antioxidant activity respectively. Both 1H NMR and FTIR spectra clearly showed that Moxi-metal complexes are formed due to change in their carboxyl stretching band in IR, H-2 and H-5 peak position in 1H NMR. All the Moxi-metal complexes showed distinguished antibacterial effects against both Gram-negative and Gram-positive bacteria as compared to drug which was found resistant against many microorganisms. Moxi-Rb and Moxi-Ag metal complexes showed higher antioxidant activity (IC50 values range from 8.26 - 9.19 µg/ml) than Moxi-Ti and Moxi-Rh metal complexes (IC50 range from 11.23 - 14.65 µg/ml). [ABSTRACT FROM AUTHOR]

Benzimidazole and its derivatives found variety of biological activities, for the searching of its potent antiinflammatory analogues, we synthesized four novel 4-(2-keto-1-benzimidazollinyl) piperidine derivatives (Q1 to Q4) by refluxing piperidine with substituted imidazole and subjected to in-vitro anti-inflammatory (ROS, NO) and antibacterial activities, structures were elucidated using spectroscopic techniques. Results revealed that compound Q1 showed most effective anti-inflammatory activity with IC50 7.6±1.3 μg/ml compared with standard Ibuprofen having IC50 11.2±1.9μg/mL. Compound Q3 showed good activity for Nitrite accumulation by stimulating macrophages test similar to standard NG Methyl L-arginine acetate with IC50 value 24.2±0.8μg/mL. The antibacterial activity of these compounds were evaluated against selected Gram+ve E. faecalis, C. diphtheriae, S. aureus and Gram -ve organism E. coli, Enterobacter aerogenes and P. aeruginosa. Synthesized compounds showed low to moderate level of antibacterial activity Q1 showed the highest antibacterial activity against Enterococcus faecalis and Escherichia coli with zone of inhibition 18mm and Q3 showed highest activity against Corynebacterium diptheriae (ZOI:18mm). Structure-activity relationship (SAR) study revealed that among all the synthesized compounds unsubstituted naphthalene (Q1) and phenyl (Q3) ring containing derivatives were most potent. [ABSTRACT FROM AUTHOR]

The species of Lactic acid bacteria are known to confer beneficial effects on the host by inhabiting in their gastrointestinal tract (GIT). They succeed in surviving the harsh conditions of the GIT by exhibiting strong tolerance against gastric acids, digestive enzymes and bile simultaneously antagonizing the pathogens by production of antimicrobials. This study has been conducted to elaborate these probiotic characteristics in vivo for which mice were intragastrically given a probiotic approved dose of 1011cfu/ml for 4 days to assess the persistence of two probiotic candidates Lactobacillus plantarum Lp36 and Lactobacillus plantarum Lp86. The fecal count of the test probiotic candidates were seen to persist well in the GIT for 15 days with a count ranging between 104-108cfu/mg of feces (p>0.01). The safety assessment of L. plantarum Lp36 in healthy and S. typhi in infected mice showed an increase in cell count from (day zero of inoculation) 106cfu/100mg of feces to108cfu/100mg (p>0.01) which was maintained till day six, suggesting the persistence in the GIT. The sections of the mice intestinal lining under scanning electron microscope revealed the adherence of Lp36 and Lp86 to the intestinal epithelia. The mice did not show any adverse effect on its health. These findings make our strains promising probiotic candidates to be used to promote health benefits after further assessments. [ABSTRACT FROM AUTHOR]

Five Lactobacillus strains isolated from vegetable and dairy products showed 99% similarity with Lactobacillus plantarum 1(Lp-1) using API –CHL 50 kit. Most of them proved to be sensitive to bacterial cell-wall inhibitors i.e. penicillin, ampicillin, amoxicillin and methicillin as studied by disc-diffusion method. These strains manifested profound tolerance to acidic-stress where Lp86 and Lp36 exhibited a good survival pattern at pH-2 for 4 hr retaining a survival count of 85% and 50%, respectively. A high survival of 85.7% was witnessed in Lp86 in presence of protease while Lp36 maintained 94.55% and 92.65% of population under the influence of enzyme pancreatin and pepsin. All the strains displayed marked tolerance against trypsin as the count did not drop below 77%. Absorbance and growth in terms of cfu/ml for bile-tolerance was examined for concentrations reflecting those in the GIT of humans, all the Lp-1 strains when grown with 1% bile showed a drop in the viable count by 1 log cycle i.e. from 1010 to 109cfu/ml. Fulfilling the above mentioned criteria these probiotic candidates displayed their capacity to reach the colon as viable metabolically active cells after successfully surviving under conditions similar to the gastrointestinal tract of humans. Upon examining the viability and stability of these probiotic candidates in most common foods serving as vehicle for probiotic delivery to the intestine, it was noticed that all the isolates tested sustained a probiotic approved number of 107 cfu/ml for effective function as recommended by WHO, after a maximum storage for one month. Hence, it could be justified that the selected probiotic candidates possess prominent probiotic potential. Therefore, L. plantarum 1 strains could prove to be an efficient probiotic after further in vivo studies to explore its safety in human subjects. [ABSTRACT FROM AUTHOR]

Bioturbation of sediments by burrowing organisms plays a key role in the functioning of coastal ecosystems. Burrowing is considered an energetically expensive activity, yet the energy costs of burrowing and the potential impacts of multiple stressors (such as salinity stress and wave action) on bioenergetics and burrowing performance of marine bioturbators are not well understood. We investigated the effects of mechanical disturbance and salinity stress on the burrowing behavior, aerobic capacity and energy expense of digging in a common marine bioturbator, the soft-shell clam Mya arenaria from the Baltic Sea (control salinity 15). Mya arenaria showed large individual variability in the burrowing efficiency, with an average of ~7% of the body energy reserves used per burial. Clams with higher mitochondrial capacity and lower energy expenditure per burial showed higher endurance. Acclimation for 3-4 weeks to low (5) or fluctuating (5-15) salinity reduced the burrowing speed and the number of times the clams can rebury but did not affect the mitochondrial capacity of the whole body or the gill. Acclimation to the fluctuating salinity shifted the predominant fuel use for burrowing from proteins to lipids. Our data indicate that the reduced burrowing performance of clams under the salinity stress is not due to the limitations of energy availability or aerobic capacity but must involve other mechanisms (such as impaired muscle performance). The reduction in the burrowing capacity of clams due to salinity stress may have important implications for survival, activity and ecological functions of the clams in shallow coastal ecosystems. [ABSTRACT FROM AUTHOR]

Salmonella regulatory protein SlyA is implicated in virulence, survival in macrophages and resistance to oxidative stress and anti-microbial peptides. SlyA is a member of the MarR family of winged-helix transcription factors. Systematic mutational analysis of the SlyA operator sequence and of the predicted DNA-binding region of SlyA shows that no single base pair in the palindromic SlyA operator sequence is essential for DNA binding, and identifies amino acid residues required to allow SlyA to recognise DNA. Combining the structure-function studies described here and elsewhere with the structures of MarR family proteins suggests a possible model for regulation of SlyA binding to DNA. [ABSTRACT FROM AUTHOR]