Potential of thermophilic amylolytic bacteria for growth in unconventional media: Potato peels

Extremozymes have gained high level of popularity for their industrial relevance. In this regard four thermophilic bacterial isolates were isolated from hot spring Chakwal in Pakistan. All the strains were screened for amylolytic activity by producing zone of clearance on starch agar plates. The bacterial isolates were cultivated employing potato peels as major energy source. All the four bacterial strains were Gram positive, motile, endospore formers and were positive for catalase and oxidase tests. Phylogenetic analysis based on 16S rRNA sequences confirmed that all the strains were belonged to the Bacillus licheniformis with 98–99% similarity under Accession numbers KF424263, KF424264, KF424265, and KF424266 for KA2, KA5, KA6, and KA9, respectively. The pH, temperature, oxygen requirement, and inocula size of the medium were optimized, which could yield amylase up to 0.61 U while growing in potato peels based media. Besides being thermostable, the enzymes have a working pH range of 5–9. The isolate KA2 showed maximum threefold purification, and percentage yield was estimated to be 93.06% as compared to crude enzyme. They yielded enough protein suggesting their potential in industrial applications in unconventional and economical substrate.

Practical applications

Amylases produced in this study could be utilized in starch hydrolysis for the production bioethanol and can be employed in different industries like food, paper, and detergent for various purposes. In addition, production of efficient amylases resolves the waste management problem of agro‐industrial waste of potato peels.     

Algebraic structures of soft sets associated with new operations

Recently new operations have been defined for soft sets. In this paper, we study some important properties associated with these new operations. A collection of all soft sets with respect to new operations give rise to four idempotent monoids. Then with the help of these monoids we can study semiring (hemiring) structures of soft sets. Some of these semirings (hemirings) are actually lattices. Finally, we show that soft sets with a fixed set of parameters are MV algebras and BCK algebras.     

A Study on Physical Properties of Melt Blended Acrylonitrile Butadiene Styrene/Ethylene Vinyl Acetate Modified with Linear Low Density Polyethylene and Montmorillonite

In this study, acrylonitrile butadiene styrene/ethylene vinyl acetate-based melt blends were prepared using linear low-density polyethylene as modifier. Commercially available sodium montmorillonite clay was organically modified and incorporated in blends. Fourier transformed infrared was used to confirm the structure of the blend and composites. Morphology of acrylonitrile butadiene styrene / ethylene vinyl acetate blend showed two-phase structure that formed a well-aligned pattern with fine nanoclay distribution. Addition of organo-modified clay depicted increase in tensile strength (43%) and modulus (89%) in damage-free range. XRD results of sodium montmorillonite, organically modified Na-montmorillonite, and PNCs were compared to investigate the degree of dispersion in matrix.     

Membrane potential and fixed-charge density across TiPO4–VPO4 composite membranes for uni-univalent electrolyte solution

The TVP composite membranes were prepared by sol–gel process, and the membrane potential has been measured for characterizing the ion-transport phenomena across a charged membrane using electrolytes (KCl, NaCl and LiCl). The membrane potential offered by the electrolytes is in the order of LiCl > NaCl > KCl, and the membrane is found to be cation-selective. The results have been used to estimate fixed-charge density, distribution coefficient, charge effectiveness and transport properties of electrolytes of this membrane. The fixed-charge density is the most important parameter, governing transport phenomena in membranes. It is estimated by the TMS method; it is dependent on the feed composition due to the prefential adsorption of some ions. The results indicate that the applied pressure is also an important variable to modify the charge density and, in turn, the performance of membrane. The order of charge effectiveness of the electrolytes in membrane depends on the ionic radii of the counter-ions. The experimental results for membrane potential are quite consistent with the theoretical prediction. The morphology of the membrane surface is studied by scanning electron micrographs (SEM).     

Enhanced Cr(vi) removal using iron nanoparticle decorated graphene

Nanoscale iron particles decorated graphene sheets synthesized via sodium borohydride reduction of graphene oxide, showed enhanced magnetic property, surface area and Cr(vi) adsorption capacity compared to bare iron nanoparticles.     

An Effective Online Collaborative Training in Developing Listening Comprehension Skills

The COVID-19 outbreak severely affected formal face-to-face classroom teaching and learning. ICT-based online education and training can be a useful measure during the pandemic. In the Pakistani educational context, the use of ICT-based online training is generally sporadic and often unavailable, especially for developing English-language instructors’ listening comprehension skills. The major factors affecting availability include insufficient IT resources and infrastructure, a lack of proper online training for speech and listening, instructors with inadequate academic backgrounds, and an unfavorable environment for ICT-based training for listening comprehension. This study evaluated the effectiveness of ICT-based training for developing secondary-level English-language instructors’ listening comprehension skills. To this end, collaborative online training was undertaken using random sampling. Specifically, 60 private-school instructors in Chakwal District, Pakistan, were randomly selected to receive online-listening training sessions using English dialogs. The experimental group achieved significant scores in the posttest analysis. Specifically, there were substantial improvements in the participants’ listening skills via online training. Given the unavailability of face-to-face learning during COVID-19, this study recommends using ICT-based online training to enhance listening comprehension skills. Education policymakers should revise curricula based on online teaching methods and modules.     

Urease-Based Biocatalytic Platforms―A Modern View of a Classic Enzyme with Applied Perspectives

Catalysis Letters - The biotechnology industry is currently seeking increased or improved enzyme efficiency and the emergence of new methods to maximize their shelf-life. Enzyme immobilization on...