Evaluation of the probiotic characteristics of Bacillus species isolated from different food sources

Probiotics have established their efficacy as dietary adjuncts providing benefits to consumers. However, selection of probiotics before incorporation into diet requires close scrutiny in the form of in vitro as well as in vivo tests. Three bacteriocinogenic Bacillus sp., namely, B. licheniformis Me1, B. flexus Hk1, and B. subtilis Bn1 previously isolated from milk, cheese and fermented beans, respectively, were characterized for typical in vitro probiotic criteria. When compared to probiotic Bacillus coagulans, all three cultures were found to possess better acid and bile tolerance. Cultures Me1 and Bn1, except Hk1, showed bile salt hydrolase activity. A marked difference in adhesion to hydrocarbons and auto-aggregation properties from 10–80 and 60–99%, respectively, were observed for the tested cultures. Highest antioxidant activity was measured for culture Hk1 (66.6%), whereas least activity of 53% was observed for culture Bn1. Cultures Me1 and Bn1 were sensitive to all the antibiotics tested, whereas Hk1 and B. coagulans showed resistance to the penicillin group of β-lactum antibiotics. All the tested cultures showed a broad spectrum of activity against food-borne pathogens. In co-cultivation studies, B. licheniformis Me1 completely inhibited the growth of the indicator pathogen Listeria monocytogenes ScottA. Overall, the test cultures exhibiting potential probiotic characteristics, particularly B. licheniformis Me1, can serve as probiotics of commercial interest.     

Density functional theory investigation of cocaine water complexes

Twenty cocaine–water complexes were studied using density functional theory (DFT) B3LYP/6-311++G** level to understand their geometries, energies, vibrational frequencies, charge transfer and topological parameters. Among the 20 complexes, 12 are neutral and eight are protonated in the cocaine-water complexes. Based on the interaction energy, the protonated complexes are more stable than the neutral complexes. In both complexes, the most stable structure involves the hydrogen bond with water at nitrogen atom in the tropane ring and C?=?O groups in methyl ester. Carbonyl groups in benzoyl and methyl ester is the most reactive site in both forms and it is responsible for the stability order. The calculated topological results show that the interactions involved in the hydrogen bond are electrostatic dominant. Natural bond orbital (NBO) analysis confirms the presence of hydrogen bond and it supports the stability order. Atoms in molecules (AIM) and NBO analysis confirms the C-H?·?·?·?O hydrogen bonds formed between the cocaine-water complexes are blue shifted in nature.     

Reactive Oxygen Species Modulate the Barrier Function of the Human Glomerular Endothelial Glycocalyx

Reactive oxygen species (ROS) play a key role in the pathogenesis of proteinuria in glomerular diseases like diabetic nephropathy. Glomerular endothelial cell (GEnC) glycocalyx covers the luminal aspect of the glomerular capillary wall and makes an important contribution to the glomerular barrier. ROS are known to depolymerise glycosaminoglycan (GAG) chains of proteoglycans, which are crucial for the barrier function of GEnC glycocalyx. The aim of this study is to investigate the direct effects of ROS on the structure and function of GEnC glycocalyx using conditionally immortalised human GEnC. ROS were generated by exogenous hydrogen peroxide. Biosynthesis and cleavage of GAG chains was analyzed by radiolabelling (S³⁵ and ³H-glucosamine). GAG chains were quantified on GEnC surface and in the cell supernatant using liquid chromatography and immunofluorescence techniques. Barrier properties were estimated by measuring trans-endothelial passage of albumin. ROS caused a significant loss of WGA lectin and heparan sulphate staining from the surface of GEnC. This lead to an increase in trans-endothelial albumin passage. The latter could be inhibited by catalase and superoxide dismutase. The effect of ROS on GEnC was not mediated via the GAG biosynthetic pathway. Quantification of radiolabelled GAG fractions in the supernatant confirmed that ROS directly caused shedding of HS GAG. This finding is clinically relevant and suggests a mechanism by which ROS may cause proteinuria in clinical conditions associated with high oxidative stress.     

Variations in random amplified polymorphic DNA profile and toxin production among isolates of Colletotrichum falcatum Went from sugarcane in Tamil Nadu,India

Red rot, caused by Colletotrichum falcatum Went, is one of the most important diseases of sugarcane (Saccharum officinarum L.). The pathogen shows a great diversity in virulence as a number of pathotypes are known to occur in nature. In the present study, the toxin producing ability and genetic variability among isolates of C. falcatum collected from major sugarcane growing areas of Tamil Nadu, India were analysed. The C. falcatum isolates differed significantly in their ability to produce toxin in vitro. The toxin from C. falcatum isolate Cf 671a induced the maximum electrolyte leakage (300 μS) from sugarcane leaf tissues. The genetic relatedness of the isolates of C. falcatum differing in toxin production potential was investigated by using RAPD analysis. Analysis of the genetic coefficient matrix derived from the scores of RAPD profiles showed that minimum and maximum percent similarities among the tested C. falcatum isolates were in the range of 19 to 95% respectively. The phylogenetic analysis by the UPGMA identified two main clusters. Cluster A contains only one isolate (Cf 98061) and all the other isolates were placed in Cluster B confirming high genetic diversity among the isolates. No correlation was observed between clustering of the C. falcatum isolates in the dendrogram and their toxin producing abilities.     

Effect of mitogen-activated protein kinases on chemokine synthesis induced by substance P in mouse pancreatic acinar cells

Substance P, acting via its neurokinin 1 receptor (NK1 R), plays an important role in mediating a variety of inflammatory processes. Its interaction with chemokines is known to play a crucial role in the pathogenesis of acute pancreatitis. In pancreatic acinar cells, substance P stimulates the release of NFκB-driven chemokines. However, the signal transduction pathways by which substance P-NK1 R interaction induces chemokine production are still unclear. To that end, we went on to examine the participation of mitogen-activated protein kinases (MAPKs) in substance P-induced synthesis of pro-inflammatory chemokines, monocyte chemoanractant protein-1 (MCP-I), macrophage inflammatory protein-lα (MIP-lα) and macrophage inflammatory protein-2 (MIP-2), in pancreatic acini. In this study, we observed a time-dependent activation of ERK1/2, c-Jun N-terminal kinase (JNK), NFκB and activator protein-1 (AP-1) when pancreatic acini were stimulated with substance P. Moreover, substance P-induced ERK 1/2, JNK, NFκB and AP-1 activation as well as chemokine synthesis were blocked by pre-treatment with either extracellular signal-regulated protein kinase kinase 1 (MEK1) inhibitor or JNK inhibitor. In addition, substance P-induced activation of ERK 112, JNK, NFκB and AP-1-driven chemokine production were attenuated by CP96345, a selective NK1 R antagonist, in pancreatic acinar cells. Taken together, these results suggest that substance P-NK1 R induced chemokine production depends on the activation of MAPKs-mediated NFκB and AP-1 signalling pathways in mouse pancreatic acini.     

The effect of nerve growth factor on the early responses during the process of wound healing

In this study, we investigated the role of nerve growth factor (NGF)-incorporated collagen on wound healing in rats. Full-thickness excision wounds were made on the back of female rats weighing about 150-160 g. Topical application of NGF-incorporated collagen, at a concentration of 1 microg/1.2 mg collagen/cm(2), once a day, for 10 days resulted in complete healing of wounds on the 15th day. The concentrations of collagen, hexosamine and uronic acid in the granulation tissue were determined. The NGF-incorporated collagen-treated rats required shorter duration for the healing with an increased rate of wound contraction. Histological and electron microscopical evaluations were also performed, which reveal the activation of fibroblasts and endoplasmic reticulum and therefore increased level of collagen synthesis due to NGF application. These results clearly indicate that the topical application of NGF-incorporated collagen enhanced the rate of healing of excision wounds.