Lactobacillus acidophilus bacteriocin, from production to their application: An overview

Antimicrobial proteinaceous compounds such as bacteriocins or bacteriocin-like compounds produced by Lactobacillus acidophilus are largely known and have been found to have potent antimicrobialactivities toward closely related bacteria and undesirable harmful microorganisms. They are useful in the fields of food preservation or safety, health care, and pharmaceutical applications. The inhibitionactivity of these substances has been reported to be strain-dependent. Binding to the epithelial cell on the gastrointestinal surfaces is one of the important factors of resident microflora to colonize the intestine. Certain L. acidophilus strains are able to produce substances that compete and prevent pathogenic bacteria from adhering to the receptors on epithelial cells of intestinal surfaces. The potential probiotic effects of L. acidophilus is well known in the human ecosystem and their production of antimicrobial peptides can contribute to elucidate the precise mechanisms by which L. acidophilus can dominate the intestinal microbiota and achieve their probiotic function. This paper presents a review of the antimicrobial proteinaceous compounds produced by various acidophilus strains, the attempts made to purify them, their characterization and useful applications

Pseudo-unitary symmetry and the Gaussian pseudo-unitary ensemble of random matrices

Employing the currently discussed notion of pseudo-Hermiticity, we define a pseudo-unitary group. Further, we develop a random matrix theory which is invariant under such a group and call this ensemble of pseudo-Hermitian random matrices as the pseudo-unitary ensemble. We obtain exact results for the nearest-neighbour level spacing distribution for (2 X 2) PT-symmetric Hamiltonian matrices which has a novel form, s log (1/s) near zero spacing. This shows a level repulsion in marked distinction with an algebraic form in the Wigner surmise. We believe that this paves way for a description of varied phenomena in two-dimensional statistical mechanics, quantum chromodynamics, and so on.Comment: 9 pages, 2 figures, LaTeX, submitted to the Physical Review Letters on August 20, 200

Dynamic user authentication based on mouse movements curves

In this paper we describe a behavioural biometric approach to authenticate users dynamically based on mouse movements only and using regular mouse devices. Unlike most of the previous approaches in this domain, we focus here on the properties of the curves generated from the consecutive mouse positions during typical mouse movements. Our underlying hypothesis is that these curves have enough discriminative information to recognize users. We conducted an experiment to test and validate our model in which ten participants are involved. Back propagation neural network is used as a classifier. Our experimental results show that behavioural information with discriminating features is revealed during normal mouse usage, which can be employed for user modeling for various reasons, such as information assets protection

In vitro cytotoxic study for partially purified Lasparaginase from fresh leaves, unripe and ripe fruits of Withania somnifera plant

This work aimed to study the cytotoxic effect of L-asparaginase isolated from local Withania somnifera plant on lymphocyte leukemia cells. To achieve this goal, L-asparaginase was purified from W. somnifera fruits by two purification steps, ion-exchange chromatography using DEAE-cellulose and gel filtration chromatography using Sephadex G-150, and the study utilized an in vitro evaluation for the cytotoxic effect of the partially purified L-asparaginase with concentrations ranging (12.5 to 100 μg/ml) in a two fold serial dilutions on some cell suspension culture including, acute lymphocyte leukemia and chronic lymphocyte leukemia culture at different concentrations (12.5 to 100 μg/ml) and different exposure time of treatment (24, 48 and 72 h). This two purification steps raised the specific activity from 1.73 U/mg in crude extract to 2.29 U/mg after ion-exchange and 10.5 U/mg after gel filtration; the purification fold was 1.32 after ion-exchange and 6.06 after gel filtration, the enzyme recovery was 56% after two purification steps and the results, pointed that acute lymphocyte leukemia culture showed highest sensitivity toward the cytotoxic effect (62.3±0.9%) of the partial purified L-asparaginase (100 μg/ml) than other culture after 48 h in a dose dependent manner, and highest cytotoxic inhibitory effect (73.2±1.6%) after 48 h of exposure on chronic lymphocyte leukemia culture, while healthy lymphocyte culture showed novel behavior. The lowest concentration of cell treatment gave the most significant (P< 0.01) inhibitory effect. The conclusion is that there is enough evidence to support the claim that Lasparaginase from W. somnifera may be considered chemotherapeutic agent against cancer, such as acute lymphoblastic leukemia and lymphosarcoma.Keywords: Acute lymphocyte leukemia (ALL), chronic lymphocyte leukemia (CLL), L-asparaginase, cytotoxic assay

Variation in physico-chemical properties of iron oxide pellets using bentonite with calcium hydroxide as binder

Bentonite and calcium hydroxide are the widely used binding materials in iron ore pelletizing plants. This investigation deals with studying the effect of using a mixture of both binders on the green, dry, and indurated iron oxide pellet properties. The binder mixtures consist of 0.4% bentonite, and varying percentage of calcium hydroxide (ranges from 0.5 to 4%). The objective is studying the possibility of partially replacing the expensive bentonite with cheap lime hydrate in pelletizing iron oxide. The results show that, on using binder mixture composed of 0.4% bentonite and 0.5% calcium hydroxide, a deterioration of the physico-chemical properties of the mill scale pellets was observed. Whereas, by increasing the percentage of calcium hydroxide in the binder mixture beyond 0.5%, a substantial enhancement in these properties was achieved

Recycling of manganese secondary raw material via cold-bond pelletizing process

Large quantities of fines were produced during the shipping, transportation, handling and storage of manganese ore sinter imported from different countries to Sinai Company for ferromanganese production. These fines are generally considered as valuable secondary raw materials. Hence, they have a potential to be recycled back to the submerged arc furnace after having been agglomerated. For agglomerates to be considered as feed materials for submerged arc furnace they must have sufficient room temperature strength. Cold-bonded pelletization process offers an economically attractive and environmentally viable method for achieving this. Ordinary Portland cement was used in this investigation for the purpose of producing a suitable coldbonded pellet from such fines. In this investigation, the effect of adding different percentages of Portland cement on the mechanical properties of both green and pellet dried at room temperature for 1, 3, 7, 14, and 28 days of normal curing were studied. The results revealed that, although the compressive strength of green pellets improved with the increase of the amount of cement added, retardation in pellet drop strength was reported. Whereas, the increase in both the cement content and time of drying leads to increase in the mechanical properties of pellets normally cured at room temperature. Pellets obtained with the addition of 9% cement shows reasonable mechanical properties to be charged in the submerged arc furnace. Ferromanganese alloy having a standard range composition was produced in a laboratory submerged arc furnace using such pellets

First genome sequences of buffalo coronavirus from water buffaloes in Bangladesh

AbstractWe report the complete genome sequences of a buffalo coronavirus (BufCoV HKU26) detected from the faecal samples of two domestic water buffaloes (Bubalus bubalis) in Bangladesh. They possessed 98–99% nucleotide identities to bovine coronavirus (BCoV) genomes, supporting BufCoV HKU26 as a member of Betacoronavirus 1. Nevertheless, BufCoV HKU26 possessed distinct accessory proteins between spike and envelope compared to BCoV. Sugar-binding residues in the N-terminal domain of S protein in BCoV are conserved in BufCoV HKU26