Polymorphic information and genetic diversity in <i>Brassica</i> species revealed by RAPD markers

Randomly amplified polymorphic DNA (RAPD) is a tremendously convenient approach used to discriminate between Brassica species owing to its accuracy and speed. RAPD primers generate adequate genetic information that can be used in the primer-marker system. In this work, twenty RAPD-PCR based markers were executed to generate polymorphic data, like polymorphic information content (PIC), mean resolving power (MRP), resolving power (RP), effective multiplex ratio (EMR), and marker index (MI) for the first time and genetic distance among and between six Brassica species were calculated. Our results indicated that 20 primers produced a total of 231 scored band and generated 87% polymorphic bands. Average PIC, MRP, RP, MI, and EMR values were 0.088, 0.65, 6.7, 0.78, and 8.9, respectively. PIC showed an overall negative correlation with MRP, RP, MI, and EMR, whereas MRP, RP, and EMR, were positively correlated with each other. Genetic identities ranged from 41.99% (between Brassica napus and Brassica oleracea) to 68.83% (between Brassica campestris and Brassica oleracea). Dendrogram results showed no clustering between species except between Brassica campestris and Brassica nigra. Nevertheless, these results will be helpful to acquire useful information about the markers and their use to determine the genomic structures of Brassica species. Further, based on genetic distance and polymorphic information, new hybrids can be developed for effective oilseed production.     

Identification of potential inhibitors for Sterol C-24 reductase of <i>Leishmania donovani</i> through virtual screening of natural compounds

Leishmaniasis is a vector-borne parasitic neglected tropical disease caused by a group of about 30 different species of the genus Leishmania. It is transmitted by the bite of female phlebotomies sand fly. Three main clinical manifestations of leishmaniasis include cutaneous, visceral, and mucocutaneous leishmaniasis. Visceral leishmaniasis (VL) caused by Leishmania donovani, is an infection of reticuloendothelial system and fatal if untreated. Cholesterol, a sterol that is prominent in the mammalian cell membranes whereas stigmasterol and ergosterol are more prevalent in plants, yeast, and protozoa, respectively. Ergosterols which is absent in human being, is an important constituent of parasite membrane. Sterol C-24 reductase (LdSR) enzyme catalyzes the final step in the ergosterol biosynthesis pathway. The inhibition of biosynthesis of ergosterol may lead to decreased cell viability and growth. Here, we performed the molecular docking-based virtual screening of a library of natural ligands against LdSR to identify a potential inhibitor to fight leishmaniasis. Capsaicin, prenyletin, flavan-3-ol, resveratrol, and gingerol showed the top binding affinity towards LdSR. Based upon ADME properties and bioactivity score, gingerol showed the best lead-likeness and drug-likeness properties. Hence, we further annotated its leishmanicidal properties. We found that gingerol inhibited the growth and proliferation of promastigotes as well as intra-macrophagic amastigotes. Gingerol exerted its antileishmanial action through the induction of reactive oxygen species (ROS) in concentration-dependent manner. Gingerol induced ROS led to apoptosis. Overall, this study described that gingerol would act as possible inhibitor to LdSR.     

Alginate Encapsulated Bifidobacteria Survival in Mayonnaise

Bifidobacterium bifidum and Bifidobacterium infantis were added to mayonnaise as either free cells or encapsulated. The survival of bifidobacteria and their effect on mayonnaise quality were evaluated. The viability of free cells disappeared after 2 wk; however, encapsulated B. bifidum survived well for 12 and B. infantis for 8 wk. Mayonnaise containing encapsulated bifidobacteria had lower total bacterial counts compared to other treatments. Yeast and mold started to appear after 12 wk of storage in mayonnaise containing encapsulated bifidobacteria and after 6 wk with other treatments (control, cells free of bifidobacteria). Mayonnaise containing encapsulated bifidobacteria had higher titratable acidity and lower TBA values than other treatments. Sensory properties of mayonnaise were improved by the addition of encapsulated bifidobacteria.     

Water Stress and Quality Decline during Storage of Tropical Leafy Vegetables

The effect of water stress (excessive water loss) on postharvest quality during storage of tropical leafy vegetables Brussica junceu L. and Amaranthus caudatus L. at ambient (24°/28°C) and low temperature (2°/4°C) regimes has been investigated. Exposed, nonsealed B. juncea and A. caudutus leaves lost water rapidly during storage at either temperature regime resulting in accelerated decrease in leaf turgidity (wilting), chlorophyll, ascorbic acid and soluble protein content, and an increase in amino acids, in the stressed leaves. Alleviation of water stress by sealing the leaves with thin plastic film restricted chlorophyll, soluble protein and ascorbic acid loss, particularly when the leaves were cooled, and maintained their turgidity. Both leafy vegetables appeared tolerant to chilling injury.     

Activation Mechanisms of Pro-Phenoloxidase on Melanosis Development in Florida Spiny Lobster (Panulirus argus) Cuticle

Phenoloxidase (PO), pro-PO [1] and pro-PO [2], isolated from cuticular extracts of early premolt spiny lobster, resolved into doublets of molecular weights 156, 151, and 96.0, 93 kD, respectively. Trypsin-activated forms of pro-PO [1] and pro-PO [2] were 123 and 83.6 kD, respectively. Apparently melanosis of shell and hyperdermal tissue in lobsters was related to stage of molt. The pro-PO forms were activated in vitro by extracts of molting fluid which is secreted into the cuticle just before molt, and the activated PO co-migrated in SDS-PAGE with the endogenously activated PO. The molting fluid was hypothesized to be the source of the natural activator(s) of pro-PO.     

Minimisation of total tardiness for identical parallel machine scheduling using genetic algorithm

In recent years research on parallel machine scheduling has received an increased attention. This paper considers minimisation of total tardiness for scheduling of n jobs on a set of m parallel machines. A spread-sheet-based genetic algorithm (GA) approach is proposed for the problem. The proposed approach is a domain-independent general purpose approach, which has been effectively used to solve this class of problem. The performance of GA is compared with branch and bound and particle swarm optimisation approaches. Two set of problems having 20 and 25 jobs with number of parallel machines equal to 2, 4, 6, 8 and 10 are solved with the proposed approach. Each combination of number of jobs and machines consists of 125 benchmark problems; thus a total for 2250 problems are solved. The results obtained by the proposed approach are comparable with two earlier approaches. It is also demonstrated that a simple GA can be used to produce results that are comparable with problem-specific approach. The proposed approach can also be used to optimise any objective function without changing the basic GA routine.     

Influence of the concentration of carbon nanotubes on electrical conductivity of magnetically aligned MWCNT–polypyrrole composites

The goal of this work is to study the effect of high magnetic pulses on electrical property of carbon nanotube–polypyrrole (CNT–PPy) composites with different CNT concentrations. CNT–PPy composites are produced in fractions of 1, 5 and 9 wt%. During the polymerization process, the CNTs are homogeneously dispersed throughout the polymer matrix in an ultrasonic bath. Nanocomposite rods are prepared. After exposure to 30 magnetic pulses, the resistivity of the rods is measured. The surface conductivity of thin tablets of composites is studied by 4-probe technique. The magnitude of the pulsed magnetic field is 10 Tesla with time duration of 1.5 ms. The results show that after applying 30 magnetic pulses, the electrical resistivity of the composites decreases depending on the concentration of CNTs in the composites. The orientation of CNTs is probed by atomic force microscopy (AFM) technique. AFM images approved alignment of CNT–polymer fibres in the magnetic field. We found that the enhancement in the electrical properties of CNT–PPy composites is due to rearrangement and alignment of CNTs in a high magnetic field. The stability of nano-composites is studied by Fourier transform infrared spectroscopy.     

Development and antibacterial performance of silver nanoparticles incorporated polydopamine–polyester-knitted fabric

Metallization is one of the finishing processes in textile treatment that can produce multifunctional effects. The present study dealt with the development of an antibacterial polyester-knitted fabric via facile and green impregnation of silver nanoparticles (SNPs). This was done by applying a polymeric foundation on the polyester-knitted fabric by simply dip-coating in the aqueous solution of dopamine. Then the SNPs were in situ fabricated and impregnated on the surface of polydopamine-modified polyester-knitted fabric in an aqueous solution of AgNO₃ at room temperature. Thus, a multi-functional finishing of polyester-knitted fabric was done. The Fourier transform infrared spectroscopy was done to confirm the polymer attachment. Scanning electron microscopy equipped with energy dispersive X-ray was done to confirm the presence of SNPs on treated fabric. The crystallography of the treated surface was examined by X-ray diffraction. The antibacterial properties of treated fabrics against broad spectrum bacterial strains were investigated and found significant.     

Output-feedback control with almost-disturbance-decoupling property—a singular perturbation approach

For square invertible and minimum-phase linear time-invariant systems, a high-gain observer-based control law is proposed. This control law provides internal stability for the closed-loop system and has the almost-disturbance-decoupling properly: that is, the influence of the disturbances on the controlled output can be made arbitrarily small.