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The growing demand and application of industrially important enzyme necessitate the need to explore new sources with diverse enzymes ranging in their specificity and activities. Enzymes are safe alternatives to chemical synthesis due to minimum side effect and ease of manufacturing. Solid state fermentation (SSF) is a cost-effective alternative to submerged fermentation with agro-residues or waste, often being used as substrate for growing diverse organisms for production of metabolites. Current study is one of the scarce report on exploring alpha amylase and cellulase production ability Aspergillus ochraceus (MTCC 1877) using wheat bran as substrate at relative humidity of 90% and at 30 ºC, for 7 days. Result showed the potential of Aspergillus ochraceus (MTCC 1877), as potential source of the two enzymes. Results revealed comparatively higher alpha amylase activity in the SSF extract of Aspergillus ochraceus (MTCC 1877) in comparison to Trichoderma longibrachiatum (ITCC 7839). On the contrary, comparatively higher cellulase activity was observed in the SSF extract of Trichoderma longibrachiatum (ITCC 7839). The results showed the potential of Aspergillus ochraceus (MTCC 1877) as a source of the two enzymes. Variation in enzymes activity may be attributed to the experimental culture conditions and may be further optimized to enhance the enzymes yield.

Bacopa monnieri (L.) Wettst. is a well documented nootropic plant, extensive known for alleviating symptoms of neurological disorder, along with other symptomatic relief. This property is attributed to the active phytocompounds, saponins (bacoside A) present in the plant. However, lack of stringent validation guidelines in most of the countries bring to the market, formulations differing in phytocompounds yield, thereby suggesting possible variation in therapeutic efficacy. The in-vitro suspension cultures of the Bacopa monnieri, provide an ease of scale-up, but regulating saponin yield is a stringent task. The aim of the study is to explore the effects of different concentrations (0, 0.25, 0.50, 0.75 and 1.0 ppm) of zinc oxide nanoparticles (ZnO NP) (24 nm in size), in regulating growth rate, bacoside yield and transcriptional profile of HMG CoA reductase gene in the suspension cells of Bacopa monnieri. Results showed a linear correlation between Bacoside A yield and ZnO NP concentrations with around 2 fold increase in total bacoside A concentration at 1 ppm. Also, ZnO NP supplemented suspension cells showed variation in the specific growth rate. Neuroprotective properties, analyzed using methanolic extracts of suspension cells again obtrude the extract of ZnO NP supplemented (0.75 ppm and 1 ppm) culture for better response in alleviating oxidative stress mediated damage to neuronal cells. ZnO NP supplemented system showed lower expression of HMG CoA reductase gene (the rate limiting step in bacoside A biosynthesis) but higher concentration of bacoside A, suggesting possible role of ZnO NP in isoprenoid pathway than MVA pathways.

Objectives To examine the neuroprotective property of triterpenoid glycoside saponins of Bacopa monnieri (L.) Wettst. bacoside A and its components against H2O2-induced oxidative stress on neuronal (N2a) cells. Methods The cytoprotective effects of individual bacoside A components were evaluated towards oxidative stressed neuronal cells. Bacoside A was screened for neuronal cell viability (MTT assay) and change in intracellular reactive oxygen species (ROS), anti-apoptotic properties and mitochondrial membrane potential (MMP) using fluorescence microscopy. Key findings Different bacoside A components showed decrease in N2a cell viability below 100 (%) after bacoside A concentration of 0.4 mg/ml. Further, cytoprotective effect of optimized dose of bacoside A was analysed for alleviating oxidative stressed, apoptosis and MMP in H2O2 stressed neuronal cells. Results showed increase in MMP, and decrease in apoptotic induction, without much change in nuclear integrity in stressed neuronal cells. Results showed bacoside A3 and bacopaside II have comparatively higher cytoprotective ability whilst isomer of bacopasponin C, bacopasaponin C and mixture showed comparatively less response. Conclusions Amongst four different bacoside A components, bacoside A3 and bacopaside II showed comparatively higher neuroprotective response analysed as higher cell viability and decreased intracellular ROS, suggesting better regulation of cyto-(neuronal) protection of N2a cells.

In this study, the effect of modified Hestrin Schramm (HS) medium supplemented with different carbon sources viz., glucose, fructose, galactose and lactic acid on the yield and physicochemical properties of bacterial cellulose (BC) produced from Gluconacetobacter xylinus strain MTCC 7795 in shake flask culture conditions was investigated. Growth studies indicated that all carbon sources supported the growth of bacteria, though specific growth rate and doubling time differs. Fructose gave the highest cellulose yield of 7.72 mg/ml after 130 h of fermentation, while yield in glucose and galactose supplemented medium were 4.49 mg/ml and 3.38 mg/ml, respectively. X-ray powder diffraction (XRD) analysis revealed that all BC samples were amorphous in comparison to commercial cellulose. Fourier transform infrared (FTIR) spectroscopic investigations of bacterial cellulose (BC) samples affirm the purity of the cellulose produced. No significant variations in physicochemical properties of cellulose samples produced with different carbon sources were observed. This study for the first time has investigated the effect of carbon sources on physicochemical properties of bacterial cellulose produced by G. xylinus MTCC 7795 and provides a strategy for economical production of BC with anticipated application in therapeutics and tissue engineering.

Chitosan/poly(vinyl alcohol) (CS/PVA) blend membranes were prepared using the casting method and their physiochemical properties were analyzed using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). FTIR and XRD demonstrated possible hydrogen bonds between CS and PVA. The addition of PVA to CS resulted in surface roughness as analyzed by SEM. The CS/PVA blend membrane exhibited high tensile properties (81.62%) and reduced water-holding capacity (53.8%) compared to a pure CS membrane (control). Cell viability and proliferation were assessed via an MTT assay with Vero cell culture. Associated with improved physicochemical properties, the CS/PVA blend membrane promotes cell proliferation of Vero cells with high specific growth rate (0.582 day-1). The results demonstrate that the blending of CS and PVA could significantly alter the surface rugosity, water-holding capacity and improve the mechanical and biological properties of the membrane. Interestingly, this concept can be extended for different anchorage-dependent cell lines, as an alternative carrier material.

Summary Summary In the present study, production, characterization and optimization of bacterial cellulose (BC) from Gluconacetobacter xylinus MTCC 7795 has been investigated. Effect of various carbon sources and bioprocess parameters on bacterial growth rate and subsequent BC production were studied and optimized. Supplementation of the media with different carbon sources resulted in varying yield of bacterial cellulose. Variations in the arrangement of bacterial cellulose with variations in carbon source were analyzed using FT-IR. Results have suggested that characteristic vibrational modes of BC produced were almost same in the typical fingerprint regions as in commercial cellulose.

Bacosides, constituents of Bacopa monnieri (Linn.), are reported to be potential therapeutic saponins in the cure of Parkinson’s disease (PD). However, detailed mechanism for control of PD by bacosides is not well documented. PD has been reported to be caused by genetic mutations in leucine-rich repeat kinase 2 (LRRK2) leading to higher kinase activity that has been identified as a major cause of familial PD. The LRRK2 was thus proposed as an important marker in the pathogenesis of PD. This suggests that inhibition of LRRK2 holds promise as a potential treatment for PD. Our study focuses on the possible application of bacoside A constituents as potential inhibitors of LRRK2. In this work, we have carried out the in silico molecular docking studies of bacoside A constituents with LRRK2, proposing their role as an inhibitor in PD. The study has revealed the significant interactions between bacosaponin and LRRK2 having ten H-bonds at receptor-ligand site with binding affinity −7.5 kcal/mol. Hence, amongst the studied triglycosidic saponins, bacosaponin was analyzed to be a better ligand, proposing it to be a major constituent in inhibiting enzymatic activities of mutated LRRK2.

Antimicrobial peptides are produced by prokaryotes and eukaryotes with fundamental role of protection against pathogenic microbes. Staphylococcus aureus, a major virulent pathogen in humans, shows multiple drug resistance and is affected by the bacteriocin activity of Mutacin IV. Currently, peptide therapeutics has been reported as a potential alternative for treating microbial infections specially exhibiting multiple drug resistance. However, the mechanism of action and interaction of peptides with target proteins is not known. The current work is an attempt to address the above issue by performing molecular docking and randomization experiments. In this study, antimicrobial peptides of bacterial origin (168 peptides) were collected from APD2 database and their net charge and hydrophobicity values were retrieved. Mutacin IV (APD Id—AP01174), a 44 amino acids long peptide derived from Streptococcus mutans UA140, was selected on the basis of high hydrophobicity to net charge ratio (0.52) and used for in silico docking studies with therapeutically important surface proteins viz. IsdA, IsdB, ClfB, and SasG of S. aureus using ZDOCK server. The docking result of IsdB surface protein and Mutacin IV was found better (ZDOCK score 1168.582) as compared to others. Afterwards, the native Mutacin IV sequence was randomized to generate 50 new combinations using EMBOSS (Shuffleseq) tool. The new sequence of Mutacin IV was screened on the basis of high in vivo to in vitro aggregation ratio (i.e. high in vivo aggregation and low in vitro aggregation values) and good binding energies against IsdB surface protein of S. aureus from the randomized sequences. The new peptide sequence showed an in vivo to in vitro aggregation ratio of 2.206 and 0.888, respectively which is higher than native sequence of Mutacin IV ratio (0.205). Moreover, the ZDOCK scores were found to be 1370.529 and 1687.048 which were better than the native sequence of Mutacin IV (ZDOCK score 1168.582). This research work identifies the new sequence of Mutacin IV peptide which binds effectively to the surface proteins of S. aureus and thereby could be a better peptide than native Mutacin IV. Our finding also demonstrates enhanced interactions of new Mutacin IV peptide with IsdB surface protein to understand the structural implications and proposes its effective antimicrobial role against S. aureus.

Acetobacter aceti MTCC 2623 was studied as an alternative microbial source for bacterial cellulose (BC) production. Effect of media components on cell growth rate, BC production and cellulose characteristics were studied. FTIR results showed significant variations in cellulose characteristics produced by A. aceti in different media. Results have shown the role of fermentation time on crystallinity ratio of BC in different media. Further, effect of six different media components on cell growth and BC production was studied using fractional factorial design. Citric acid was found to be the most significant media component for cell growth rate (95% confidence level, R(2)=0.95). However, direct role of these parameters on cellulose production was not established (p-value>0.05).

Pseudomonas aeruginosa is an opportunistic bacterium known for causing chronic infections in cystic fibrosis and chronic obstructive pulmonary disease (COPD) patients. Recently, several drug targets in Pseudomonas aeruginosa PAO1 have been reported using network biology approaches on the basis of essentiality and topology and further ranked on network measures viz. degree and centrality. Till date no drug/ligand molecule has been reported against this targets.In our work we have identified the ligand /drug molecules, through Orthologous gene mapping against Bacillus subtilis subsp. subtilis str. 168 and performed modelling and docking analysis. From the predicted drug targets in PA PAO1, we selected those drug targets which show statistically significant orthology with a model organism and whose orthologs are present in all the selected drug targets of PA PAO1.Modeling of their structure has been done using I-Tasser web server. Orthologous gene mapping has been performed using Cluster of Orthologs (COGs) and based on orthology; drugs available for Bacillus sp. have been docked with PA PAO1 protein drug targets using MoleGro virtual docker version 4.0.2.Orthologous gene for PA3168 gyrA is BS gyrAfound in Bacillus subtilis subsp. subtilis str. 168. The drugs cited for Bacillus sp. have been docked with PA genes and energy analyses have been made. Based on Orthologous gene mapping andin-silico studies, Nalidixic acid is reported as an effective drug against PA3168 gyrA for the treatment of CF and COPD.

Laccase production by an indigenously isolated white rot basidiomycete Coriolus sp. in solid-state fermentation was (SSF) studied. Bioprocess variables (pH, relative humidity (RH), nitrogen source (gram flour) and incubation time) were optimized in SSF using Plackett–Burman design. Laccase yield of 404.23 U/g dry substrate (U/gds) was obtained in control conditions using wheat bran as solid substrate after 10 days of studies with 80% RH at 30 °C and five agar plugs as the inoculum. Further, 6.5 fold increase in laccase activity (2661.36 U/g dry substrate) was achieved at RH 89%; gram flour 1 g/5 gds; pH 5.0 and 10 days of incubation. Statistical analysis showed RH as most significant parameter and incubation time to be least significant parameter for laccase production. Proposed mathematical model based on multiple regression was in complete agreement with experimental observation. Thus, the indigenous isolate seems to be a potential laccase producer using SSF.

Cloning and expression of any heterologous gene product always impart metabolic load on the recombinant host for utilization of its metabolites that results in variations in cellular physiology. An understanding of such stress is important for robust process design and scale-up. In the present communication, an attempt has been made to explain the metabolic load imposed on the recombinant strain of Escherichia coli BL21(DE3) owing to over-expression of amyE gene, using different expression vectors of varying size. Current studies show that metabolic quotient or specific oxygen uptake rate (SOUR) of different recombinant hosts increases with an increase in vector size, showing correlation between vector size and cellular metabolic load. Further increase in SOUR on protein expression shows even higher metabolic load for protein expression than plasmid maintenance. Increase in bacterial size and decrease in specific growth rate on transformation and recombinant protein expression are cellular respon...

Plastic materials, particularly polyethylene, are the potential source of environmental pollution. In the present study, a fungal strain was isolated from plastic waste dumpsites capable of adherin...

Technological advancement in molecular biology techniques has proved to be useful in successful overexpression of recombinant proteins. However, one of the major issues of concern is the instability of recombinant plasmid when the recombinant hosts are grown without selection pressure. Current study proposes a correlation between segregational instability and plasmid size. In order to explain the segregational instability, existing mathematical model have been used. Four different recombinant vectors pET29b, pET32b, pET43b and pCS22, all having 1.5 kb α-amylase gene (amyE) insert from Bacillus amyloliquefaciens were used in the study. Culture when grown in repeated batch without suitable selection pressure showed plasmid free cells generating from plasmid bearing cells. Segregational instability of 2.2 × 10−3 and 1.4 × 10−3 per generation was observed with pET43b-amyE plasmid and pCS22-amyE plasmid respectively. This is the first report on segregational instability of commercially available vectors. A mathematical correlation has been proposed between plasmid size and rate of segregational loss per generation (R).

The blend membranes with varying weight ratios of chitosan/poly (vinyl alcohol) (CS/PVA) (1:0, 1:1, 1:2.5, 1.5:1, 1.5: 2.5) were prepared using solvent casting method and were evaluated for their potential application in single-use membrane bioreactors (MBRs). The physicochemical properties of the prepared membranes were investigated for chemical interactions (FTIR), surface morphology (SEM), water uptake, protein sorption (qe), ammonia sorption and growth kinetics of Vero cells. CS/PVA blend membrane having weight ratio of 1.5:1 had shown enhanced membrane flexibility, reduced water uptake, less protein sorption and no ammonium sorption compared to CS membrane. This blend membrane also showed comparatively enhanced higher specific growth rate (0.82/day) of Vero cells. Improved physicochemical properties and growth kinetics obtrude CS/PVA (1.5:1) as a potential surface for adhesion and proliferation with possible application in single use membrane bioreactors. Additionally, new insight explaining correlation between water holding (%) of CS/PVA (1.5:1) blend membrane and doubling time (td) of Vero cells is proposed.