Rukhsana Satar

New vision to CuO, ZnO, and TiO2 nanoparticles: their outcome and effects

Nanomaterials and nanotechnology have attracted more and more attention due to their wide ranges of applications in various fields. With a high level of surface energy, high magnetism, high surface area, and low melting point, engineered nanoparticles (ENPs) has been widely used in industry for various applications. Metal nanoparticles, in particular, have been shown to cause significant biological effects. Review discusses cytotoxic to neurotoxic effects of CuO, ZnO, and TiO2 nanoparticles based on the scenario drawn from various in vitro and in vivo studies. ENPs such as TiO2 and ZnO NPs have great practical importance in industrial applications. CuO NPs is also widely used in biomedical applications as catalyst supports, drug carriers, and gene delivery. However, study conducted on TiO2 NPs have forecast that oxidative DNA damage could be attributed due to reduced glutathione levels with concomitant increase in lipid peroxidation and reactive oxygen species generation. Moreover, there are many evidences showing that ZnO NP and CuO NPs generates ROS production and can cause cell death in different types of cultured cell. Nanoparticle toxicity is assessed by set of tests designed to characterize a given risk and also the mechanism for related outcomes. Conclusively, it becomes more and more important for nanotechnologist to understand the potential health effects of ENPs and what new methodology can be applied to reveal problems like gene silencing and inhibition in antioxidant defense mechanism which can be occurred on severe effects to oxidative stress by ENPs.

Immobilization of Aspergillus oryzae β-Galactosidase on Cellulose Acetate-Polymethylmethacrylate Membrane and Its Application in Hydrolysis of Lactose from Milk and Whey

The present study demonstrates the immobilization of Aspergillus oryzae β-galactosidase on cellulose acetate-polymethylmethacrylate (CA-PMMA) membrane and its application in hydrolyzing lactose in dairy industries. The effect of physical and chemical denaturants like pH, temperature, product inhibition by galactose, storage stability, and reuse number of the enzyme immobilized on CA-PMMA membrane has been investigated. Lactose was hydrolyzed from milk and whey in batch reactors at 50°C by free and immobilized β-galactosidase (IβG). Optimum pH for the free and immobilized enzyme was found to be the same, that is, 4.5. However, IβG retained greater fractions of catalytic activity at lower and higher pH ranges. The temperature optimum for the immobilized enzyme was increased by 10°C. Moreover, Michaelis-Menten constant was increased for IβG as compared to the native one while maximum reaction rate was reduced for the immobilized enzyme. The preserved activity of free and immobilized enzyme was found to be 45% and 83%, respectively, after five weeks of storage at 4°C. Reusability of IβG was observed to be 86% even after fifth repeated use, thereby signifying its application in lactose hydrolysis (as shown in lab-scale batch reactors) in various dairy products including milk and whey.

Current opinion in Alzheimerʼs disease therapy by nanotechnology-based approaches

Purpose of review Nanotechnology typically deals with the measuring and modeling of matter at nanometer scale by incorporating the fields of engineering and technology. The most prominent feature of these engineered materials involves their manipulation/modification for imparting new functional properties. The current review covers the most recent findings of Alzheimers disease (AD) therapeutics based on nanoscience and technology. Recent findings Current studies involve the application of nanotechnology in developing novel diagnostic and therapeutic tools for neurological disorders. Nanotechnology-based approaches can be exploited for limiting/reversing these diseases for promoting functional regeneration of damaged neurons. These strategies offer neuroprotection by facilitating the delivery of drugs and small molecules more effectively across the blood–brain barrier. Summary Nanotechnology based approaches show promise in improving AD therapeutics. Further replication work on synthesis and surface modification of nanoparticles, longer-term clinical trials, and attempts to increase their impact in treating AD are required.

Role of Nanodiamonds in Drug Delivery and Stem Cell Therapy

Context The use of nanotechnology in medicine and more specifically drug delivery is set to spread rapidly. Currently many substances are under investigation for drug delivery and more specifically for cancer therapy. Evidence Acquisition Nanodiamonds (NDs) have contributed significantly in the development of highly efficient and successful drug delivery systems, and in stem cell therapy. Drug delivery through NDs is an intricate and complex process that deserves special attention to unravel underlying molecular mechanisms in order to overcome certain bottlenecks associated with it. It has already been established that NDs based drug delivery systems have excellent biocompatibility, nontoxicity, photostability and facile surface functionalization properties. Results There is mounting evidence that suggests that such conjugated delivery systems well retain the properties of nanoparticles like small size, large surface area to volume ratio that provide greater biocatalytic activity to the attached drug in terms of selectivity, loading and stability. Conclusions NDs based drug delivery systems may form the basis for the development of effective novel drug delivery vehicles with salient features that may facilitate their utility in fluorescence imaging, target specificity and sustainedrelease.

CARBOXYLATION OF SILVER NANOPARTICLES FOR THE IMMOBILIZATION OF β-GALACTOSIDASE AND ITS EFFICACY IN GALACTO-OLIGOSACCHARIDES PRODUCTION

The present study investigated the carboxylation of silver nanoparticles (AgNPs) by 1:3 nitric acid-sulfuric acid mixtures for immobilizing Aspergillus oryzae β-galactosidase. Carboxylated AgNPs retained 93% enzyme upon immobilization and the enzyme did not leach out appreciably from the modified nanosupport in the presence of 100 mmol L-1 NaCl. Atomic force micrograph revealed the binding of β-galactosidase on the modified AgNPs. The optimal pH for soluble and carboxylated AgNPs adsorbed β-galactosidase (IβG) was observed at pH 4.5 while the optimal operating temperature was broadened from 50 oC to 60 oC for IβG. Michaelis constant, Km was increased two and a half fold for IβG while Vmax decreases slightly as compared to soluble enzyme. β-galactosidase immobilized on surface functionalized AgNPs retained 70% biocatalytic activity even at 4% galactose concentration as compared to enzyme in solution. Our study showed that IβG produces greater amount of galacto-oligosaccharides at higher temperatures (50 oC and 60 oC) from 0.1 mol L-1 lactose solution at pH 4.5 as compared to previous reports.

Antibacterial activity of iron oxide nanoparticles synthesized by co-precipitation technology against Bacillus cereus and Klebsiella pneumoniae

Abstract The present study investigates the synthesis and characterization of iron oxide nanoparticles (Fe3O4-NPs) for their antibacterial potential against Bacillus cereus and Klebsiella pneumonia by modified disc diffusion and broth agar dilution methods. DLS and XRD results revealed the average size of synthesized Fe3O4-NPs as 24 nm while XPS measurement exhibited the spin-orbit peak of Fe 2p3/2 binding energy at 511 eV. Fe3O4-NPs inhibited the growth of K. pneumoniae and B. cereus in both liquid and soild agar media, and displayed 26 mm and 22 mm zone of inhibitions, respectively. MIC of Fe3O4-NPs was found to be 5 μg/mL against these strains. However, MBC for these strains was observed at 40 μg/mL concentration of Fe3O4-NPs for exhibiting 40–50% loss in viable bacterial cells and 80 μg/mL concentration of Fe3O4-NPs acted as bactericidal for causing 90–99% loss in viability. Hence, these nanoparticles can be explored for their additional antimicrobial and biomedical applications.

Role of Glutaraldehyde in Imparting Stability to Immobilized β-Galactosidase Systems

This review article highlights the role of glutaraldehyde as a matrix activator/stabilizer in imparting higher operational and thermal stability to β-galactosidase (βG) for biotechnological applications. Glutaraldehyde has been used extensively as a crosslinking agent as well as for functionalization of matrices to immobilize βgalactosidase. Immobilized β-galactosidase systems (IβGS) obtained as a result of glutaraldehyde treatment has been employed to hydrolyze whey and milk lactose in batch reactors, continuous packed-bed and fluidized bed reactors under various operational conditions. Moreover, these IβGS have also been utilized for the production of galactooligosaccharides in food, dairy and fermentation industries. It was observed that glutaraldehyde provided remarkable stability to immobilize βG against various physical/chemical denaturants, thus enhancing thermal/operational stability and rendering it more suitable for repeated utilization in industrial scale operations.

Investigating the antibacterial potential of agarose nanoparticles synthesized by nanoprecipitation technology

Abstract Herein, an effort was made to investigate the antibacterial potential of agarose nanoparticles (ANPs) and poly(quaternary ammonium) modified ANPs (mANPs) against Escherichia coli (gram-negative bacterium) and Staphylococcus aureus (gram positive bacterium) in liquid systems as well as on agar plates. ANPs were synthesized by nanoprecipitation technology and characterized by XRD, TEM, TGA, DTA and DLS. The particle size estimated was 30 nm while atomic force microscopy was used to observe the interaction of ligand on ANPs. Antimicrobial characterization was monitored by colony forming units (CFU) as a function of ANPs concentration on agar plates. It was observed that ANPs showed 15 × 109/ml CFU after 24 hours of incubation at 20 mM ANPs concentration while the modified ANPs exhibited 21 × 109/ml CFU under similar incubation conditions. Moreover, zone of inhibition (ZOI) was 2.9 and 3.8 cm, respectively for E. coli by ANPs at 0.2 and 0.4 mM, respectively while it was 3.2 and 3.8 cm respectively by modified ANPs under similar conditions. Similarly, ZOI for S. aureus by ANPs at 0.2 and 0.4 mM was observed at 3.1 and 4.0 cm, respectively, while these values were 3.5 and 4.1 cm, respectively for modified ANPs under similar incubation conditions.

Future Applications of Apricot (Prunus Armeniaca Kaisa) ß Galactosidase in Dairy Industry

Abstract The present study demonstrates the immobilization of β galactosidase from apricots (Prunus armeniaca kaisa) on an inexpensive concanavalin A layered cellulose-alginate hybrid gel. Immobilized β galactosidase retained 78% of the initial activity after crosslinking by glutaraldehyde. It exhibited greater fraction of activity at both acidic and basic pH, and showed broad spectrum temperature optimum as compared to free enzyme. Moreover, immobilized enzyme exhibited higher thermal stability at 60°C and retained 80% of the original enzyme activity in presence of 3% galactose. The crosslinked immobilized enzyme showed improved hydrolysis of lactose from milk and whey in batch processes at 50°C as well as in continuous reactors operated at fl ow rate of 20 mL/h and 30 mL/h even after one month. Moreover, crosslinked adsorbed β galactosidase retained 76% activity even after its sixth repeated use, thereby promoting its use for lactose hydrolysis in various dairy products even for longer durations.

UTILITY OF FUNCTIONALIZED AGAROSE NANOPARTICLES IN HYDROLYZING LACTOSE IN BATCH REACTORS FOR DAIRY INDUSTRIES

Shakeel Ahmed Ansaria,*, Syed Ismail Ahmadb, Mohammad Alam Jafria, Muhammad Imran Naseera and Rukhsana Satarc Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah-21589, Kingdom of Saudi Arabia Physics Division, Department of Basic Sciences, Ibn Sina National College for Medical Studies, Jeddah-21418, Kingdom of Saudi Arabia Department of Biochemistry, Ibn Sina National College for Medical Sciences, Jeddah-21418, Kingdom of Saudi Arabia