[en] The present study describes the production, purification and characterization of alkaline protease from mutant strain of Bacillus subtilis EMS-8. The enzyme was purified using ammonium sulphate precipitation which gave 2.64 fold purification with 81.5% yield at 70% saturation. The molecular weight of the enzyme was determined using SDS-PAGE and it was found to be 25 KDa. The optimum pH of enzyme activity was 8.5; however the enzyme remained stable up to pH 10 after 24 hrs of incubation. Similarly, the optimum temperature for enzyme activity was 40 degree C, whereas it remained stable up to 90 degree C with greatly reduced activity. Alkaline protease showed highest specificity towards casein. Among different inhibitors, Phenylmethylsulphonyl fluoride (PMSF) completely inhibited the enzyme activity indicating the serine nature of protease. Similarly, the protease activity was greatly reduced in the presence of MnCl/sub 2/, whereas MgCl/sub 2/ enhanced its activity. The shelf life of the protease was also determined and it was found that the activity of the enzyme came to an end after second week, when the enzyme was stored at room temperature. (author)

[en] A case is reported of a 42 year-old female who presented with the painful upper left first molar. Comprehensive clinical examination did not reveal the cause of the pain which got progressively worse. The tooth was extracted on the insistence of the patient. Microscopic examination of multiple sections of the decalcified tooth showed a large freestone which occupied most of the pulp chamber and was closely related to a nerve bundle. The finding tended to support the view that pulp stones in an apparently healthy tooth may cause toothache. (author)

[en] Polymer blend technology has earned a significant position in the field of polymer science. Current membrane technology can easily and simply remove and separates carbon dioxide as pressure, temperature, costs, and energy requirements are low. There is also no corrosion problem from the straightforward process of removing CO2 from natural gas, especially in remote or offshore locations that are easily scaled up. However, glassy polymeric membranes suffer from a lack of permeability causing performance degradation and higher selectivity. Nevertheless, amine solutions are capable of purifying naturally acidic gas. Within this framework, the blending of the polysulfone (PSU) glassy polymer with amines such as diethanolamine (DEA), methyl diethanolamine (MDEA), and monoethanolamine (MEA) in a dimethylacetamide solvent, resulted in the development of flat sheet membranes with the desired properties. The findings showed good miscibility between PSU and amines blends, all the original functional groups were shown by FTIR. The synthesized amine polymer blend membrane were found to have homogenous surfaces and a packed bed sphere structure (PBSS) as shown by FESEM images. Furthermore the addition of different amine solution, have increased the size of PBSS due to incorporation of amine molecule into the sphere. (author)

[en] Lipases are the enzymes of choice for applications in a large number of industries. Present study describes the isolation of potent lipolytic fungal strains and their subsequent production by using shake flasks fermentation technique. The selected isolate was identified as Aspergillus terreus, based on morphological features and 18s rRNA sequencing. Seven different culture media were analyzed for the extracellular lipase production employing A. terreus as the production organism and it was found that M6 gave maximum lipase production i.e., 5.0 U/mL/min in the medium containing (% w/v) MgSO4, 0.05; NaNO3, 0.05; KCl, 0.05; KH2PO4, 0.2; olive oil, 1.0; pH 6.0. Maximum production of lipase (7.66 U/mL/min) was found at a medium pH of 6.0 and an incubation temperature of 30 degree C after 72 hrs of incubation period. An increase in the lipase production (7.99 U/mL/min) was observed when the production medium was provided with 1.0% peptone, 2.0% glucose and 1.0% olive oil. Ammonium sulphate precipitation was carried out for the partial purification of the lipase and maximum purification of the enzyme was found at 80% saturation level of ammonium sulphate with 1.812 fold purification. (author)

[en] While BP metabolism in liver has been extensively studied relatively little work has been performed in extrahepatic tissues such as brain. It has been shown that brain of fetal and adult mice and rats converts PAH(s) including BP to mutagenic and cytotoxic metabolities. These studies have focused on characterization of AHH activity in brain microsomes and mitochondria. In this communication the authors report the distribution and retention of radiolabeled BP in discrete regions of rat brain

[en] To gain a better understanding of protein adsorption onto biomaterial surfaces is required for the control of biocompatibility and bioactivity. Various samples of diamond like carbon (DLC) and silicon-doped DLC were synthesised using plasma enhanced chemical vapour deposition (PECVD). The effects of surface morphology on the interaction of human serum albumin (HSA) with doped and undoped DLC films was investigated using spectroscopic ellipsometry (SE) and other surface analysis techniques. The results highlighted an increase in both contact angle and hydrophobicity with increasing silicon dopant levels. A reduction on the contact angle values. After adsorption of HSA, the films showed a reduction in the contact angle with a significant change in the cosΔ and this gap increased with increasing surface coverage of HSA. The adsorption kinetics of HSA were also investigated and revealed that the maximum adsorption occurred at pH 5.0 and the process involved chemisorption. The experimental isotherm data were analysed using the Langmuir and Freundlich‎ models. The amount of HSA adsorbed increased with contact time and reached saturation ‎after 30 min. The adsorption ‎process was found to be pseudo first order with respect to the bulk concentration and was dependent on both the concentration of protein and surface characteristics of the samples. The amount of adsorbed HSA was higher with higher levels of silicon doping of the DLC. Therefore, doping DLC may provide an approach to controlling the protein adsorption. - Graphical abstract: The average thickness layer of HSA measurement onto surfaces of DLC and Si-DLC. - Highlights: • Diamond Like Carbon (DLC) and Silicon doped DLC were synthesised and characterised. • Si-DLC increases the hydrophobicity and decreases the surface free energy. • Adsorption study using human serum albumin (HSA). • The adsorbed amount of HSA increases with increasing of Silicon content DLC. • Adsorption process follow pseudo first order and Freundlich adsorption isotherm

[en] Increasing resistance of microbes against antimicrobial drugs keep scientists busy in exploring novel and potent antibiotics. The present study is concerned with the production of antitumor antibiotic from Streptomyces griseocarneus NRRL B1068 using submerged fermentation technique. The antibiotic activity was tested against three test microorganisms including A. niger, E. coli and B. subtilis by agar well diffusion method. The production of antibiotic was enhanced by optimizing culture and physical conditions. Different culture media were screened and M1 medium consisting of (g/L), potassium dihydrogen phosphate, 3.24; dipotassium hydrogen phosphate, 5.65; hydrated magnesium sulphate, 1.0; and 1 ml stock solution of salts (ferrous sulphate, 0.1; manganese chloride, 0.1; and zinc sulphate, 0.1) supplemented with 7.5% glucose and 2.0% lysine was found best for antibiotic synthesis. Optimum temperature, pH and incubation period for the production of antitumor antibiotic were found to be 30ºC, 7.2 and 7 days, respectively. Seven days old inoculum in a concentration of 8% (v/v) was determined best for antitumor antibiotic production by Streptomyces griseocarneus NRRL B1068. (author)

[en] The cytochrome P-450 in hepatic microsomes prepared from rats pretreated with hematoporphyrin derivative was shown to be rapidly destroyed in the presence of long-wave ultraviolet light. The photocatalytic destruction of the heme-protein was dependent on both the dose of ultraviolet light and of hematoporphyrin derivative administered to the animals. The destructive reaction was accompanied by increased formation of cytochrome P-420, loss of microsomal heme content, and diminished catalytic activity of cytochrome P-450-dependent monooxygenases such as aryl hydrocarbon hydroxylase and 7-ethoxycoumarin O-deethylase. The specificity of the effect on cytochrome P-450 was confirmed by the observation that other heme-containing moieties such as myoglobin and cytochrome c were not susceptible to photocatalytic destruction. The destruction of cytochrome P-450 was a photodynamic process requiring oxygen since quenchers of singlet oxygen, including 2,5-dimethylfuran, histidine, and beta-carotene, each substantially diminished the reaction. Scavengers of superoxide anion such as superoxide dismutase and of H₂O₂ such as catalase did not protect against photodestruction of cytochrome P-450, whereas inhibitors of the hydroxyl radical, including benzoate, mannitol, and ethyl alcohol, did afford protection. These results indicate that lipid-rich microsomal membranes and the heme-protein cytochrome P-450 embedded therein are potential targets of injury in cells exposed to hematoporphyrin derivative photosensitization

[en] For efficient gas separation the membrane technology is rapidly growing day by day and it is more economical and effectual than past technologies. The main objective of this study is to synthesis polymer blend membranes (PBM) using glassy polysulfone (PSU) and rubbery polyvinyl acetate (PVAc) with the addition of methyl diethanol amine for removal of CO/sub 2/ from CH4. The PBM were developed by varying the composition of PVAc ranging from 5 to 20 wt % with 80 to 100 wt % PSU in DMAc solvent. The amine composition was added to the blend and kept at 10 wt %. The present of MDEA in the PBM had increased the CO/sub 2/ permeance as compare with the based polymer membranes. However as the operating pressure increased from 2 to 10 bar, the PBM (PSU95 percent/PVAc5 percent) with MDEA was found to increase significantly the permeance of CO/sub 2/, hence increasing the separation factor from 9.98+-0.02 to 30.19+-0.49. EPBM was found a very promising to be used for CO/sub 2/CH/sub 4/ separation. (author)

[en] The present study gives an insight into the effect of different activators and inhibitors on the activity and stability of alkaline proteases produced by Bacillus subtilis IH-72. The alkaline protease was strongly activated both by bivalent and monovalent cations such as Mg/sup 2+/, Mn/sup 2+/, Na/sup +/ and K/sup +/. The enzyme activity was considerably enhanced in the presence of fructose, galactose, glucose and mannitol. The enzyme was stabilized up to 10 days by immobilization on activated charcoal and was efficiently stabilized up to 2 months by lyophilization. The enzyme remained stable up to 19 days both at 4 degree C and 30 degree C in the presence of Mn/sup 2+/. However, it exhibited significant stability up to 22 days at 4 degree C and 30 degree C in the presence of fructose, galactose and polyethylene glycol. (author)