The grape is one of the most valued conventional fruits, worldwide. Although most of the parts of the grapevine are useful, primarily, the grape is considered as a source of unique natural products not only for the development of valuable medicines against a number of diseases, but also for manufacturing various industrial products. Over the last few decades, apart from the chemistry of grape compounds, considerable progress has been made towards exploring the biological activities of various grape-derived constituents. Today, it is well established that in addition to serving as food, the grape is a major source of several phytochemicals. The main biologically active and well-characterized constituent from the grape is resveratrol, which is known for various medicinal properties in human diseases. This review discusses the roles of various grape-derived phytochemicals in relation to various diseases.

Dengue is an arthropod-borne viral disease caused by four antigenically different serotypes of dengue virus. This disease is considered as a major public health concern around the world. Currently, there is no licensed vaccine or antiviral drug available for the prevention and treatment of dengue disease. Moreover, clinical features of dengue are indistinguishable from other infectious diseases such as malaria, chikungunya, rickettsia and leptospira. Therefore, prompt and accurate laboratory diagnostic test is urgently required for disease confirmation and patient triage. The traditional diagnostic techniques for the dengue virus are viral detection in cell culture, serological testing, and RNA amplification using reverse transcriptase PCR. This paper discusses the conventional laboratory methods used for the diagnosis of dengue during the acute and convalescent phase and highlights the advantages and limitations of these routine laboratory tests. Subsequently, the biosensor based assays developed using various transducers for the detection of dengue are also reviewed.

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The last few years have produced a revolution in the development of very sensitive, rapid, automated, molecular detection methods for a variety of various species of lactic acid bacteria (LAB) associated with food and dairy products. Nowadays many such strains of LAB are considered probiotics. The genome-based methods are useful in identifying bacteria as a complementary or alternative tool to phenotypical methods. Over the years, identification methodologies using primers that target different sequences, such as the 16S ribosomal RNA (rRNA)-encoding gene, the 16S-23S rRNA intergenic spacer region, the 23S rRNA-encoding, recA and ldhD genes; randomly amplified polymorphic DNA, restriction fragment length polymorphism, denaturing gradient gel electrophoresis, temperature gradient gel electrophoresis, amplification rDNA restriction analysis, restriction enzyme analysis, rRNA, pulse field gel electrophoresis and amplification fragment length polymorphism have played a significant role in probiotic bacteriology. Hence, the aim of this review is to provide an overview of some rapid and reliable polymerase chain reaction-based molecular methods used for identifying and differentiating closely related species and strains of LAB associated with food and industry.

The electronic structure, electrical and dielectric properties of barium stannate, a semiconducting perovskite oxide prepared by solid state ceramic route were studied by employing X-ray photoelectron spectroscopy (XPS), Mössbauer and impedance spectroscopic techniques in the temperature range 77–300 K. X-ray diffraction (XRD) pattern of BaSnO3 confirms the cubic structure. Scanning electron microscopy (SEM) images show high porosity in the sample and the average grain size was found to be about 1.85 µm which corroborates with the particle size obtained through XRD line broadening analysis. Mössbauer spectra, at 298 and 78 K reveal that tin exists mainly in tetravalent, Sn4+ state. XPS study also shows the same results but it indicates the existence of a trace amount of Sn2+. Electrical conductivity and dielectric constant of this system have been measured in the temperature range 298 to 148 K and in the frequency range 10-2 to 106 Hz. Frequency and temperature dependent electrical conductivity/dielectric properties have been used to separate the contributions of grains and grain boundaries to the total observed conductivity and dielectric constant. Orientational polarisation and space charge polarisation contributes to the observed dielectric properties of the system.