Flaxseed Cysteine Protease Exhibits Strong Anticoagulant, Antiplatelet, and Clot-Dissolving Properties.

In this study, we purified and characterized flaxseed cysteine protease (FSCP) with strong anticoagulant, antiplatelet, and clot-dissolving properties. The enzyme was purified to homogeneity by a combination of gel permeation and ion-exchange column chromatography techniques. The purity of the enzyme was evaluated by SDS-PAGE, RP-HPLC, and MALDI-TOF. FSCP was observed as a single band of approximately 160 kDa in SDS-PAGE under reducing and non-reducing conditions. The exact molecular mass of FSCP was found to be 168 kDa by MALDI-TOF spectrometry. The CD spectra of FSCP revealed the presence of 25.6% helices, 25.8% turns, and 48% random coils with no beta-sheet structures. FSCP hydrolyzed both casein and gelatin with a specific activity of 3.5 and 4.2 unit/mg min respectively. The proteolytic activity of FSCP was completely abolished by iodoacetic acid (IAA), suggesting FSCP is a cysteine protease. The pH optimum for the proteolytic activity of FSCP was pH 6.0; the temperature optimum was 30°C. FSCP exhibited strong anticoagulant effect in both platelet-rich plasma (PRP) and platelet-poor plasma (PPP) by extending the clotting time from 222 to 1100 s and from 256 to 1210 s, respectively. FSCP degraded human fibrinogen and fibrin clots. The products of fibrinogen degradation by thrombin and FSCP were different. Furthermore, FSCP inhibited aggregation of washed platelets triggered by ADP, epinephrine, thrombin, collagen, arachidonic acid, and platelet activating factor (PAF). FSCP was found to be nontoxic as it did not damage the membrane of red blood cells (RBCs) and did not induce hemorrhage and edema in experimental mice.

Enhanced bactericidal activity of modified titania in sunlight against Pseudomonas aeruginosa, a water-borne pathogen.

Photocatalyst-mediated inactivations generate reactive oxygen species and OH radicals, which induce oxidative destruction of membrane integrity, causing damage to membrane phospholipids of gram negative bacteria like Pseudomonas aeruginosa. Nanosized TiO(2) was synthesized by gel to crystalline conversion and Zr-doped TiO(2) was synthesized by pulverization using appropriate precursor. The doped nanocrystals retained the anatase phase with a marginal increase in crystallite size, averaging at 25nm. SEM-EDX analysis of the doped sample depicts the substantial growth of grain size with 1.33 atomic weight % of zirconium. The created electron states in the doped sample act as charge carrier traps suppressing recombination which later detraps the same to the surface of the catalyst causing enhanced interfacial charge transfer. Zr-doped TiO(2) at the molecular scale exhibits better photocatalytic activity with lower bandgap energy that can respond to visible light. The redshift caused by the dopants in absorption spectra of TiO(2) facilitated the nonintrinsic sample to exhibit nearly 2-fold enhancement of photoinactivation in sunlight. Extent of photoinactivation of P. aeruginosa was observed to be complete (100%) within 150min of sunlight exposure in the presence of modified TiO(2) .

Synthesis and comparative study of nano-TiO2 over Degussa P-25 in disinfection of water.

Nanostructured TiO(2) crystals were synthesized by gel to crystalline conversion. The crystals obtained were anatase form of titania averaging in 30 nm particles with an intrinsic band gap of 3.1 eV. The photocatalytic behavior was evaluated for the bactericidal effect in water, contaminated with the indicator organism Escherichia coli. The 100% photoinactivation of E. coli was achieved within 60 min with suspended nano-TiO(2). The catalytic activity of synthesized nanosample was observed to be 2.6 times more than that of commercial TiO(2) sample referred to as Degussa P-25. The photoinactivation of E. coli was tested with irradiation source of different wavelengths to substantiate the influence of particle size and nano crystallinity on electronic band structure. The photoactivity of nano titania enhanced to 1.625 times when the source of irradiation shifted from 360 to 400 nm while Degussa P-25 showed no change.