Development and application of DPPH impregnated paper based color sensor disc to detect vegetable oils addition in cow ghee.

Ghee is a premium product in Southeast Asia and is prone to adulteration with vegetable oils/ fats. The main aim of the study was to develop an easy-to-use paper-based sensor to detect this adulteration. Hence, a protocol involving hexane and acetonitrile for the extraction of synthetic antioxidants from adulterated ghee and its rapid detection using DPPH was standardized. Paper-based discs impregnated with 4 mM DPPH were developed. The developed paper-based disc sensors worked well and their response time was indirectly proportional to the antioxidant concentration (0.0025-0.02%). Using the developed disc sensors, the palm oil, and sunflower oil added to cow ghee @2.5% or more, and 1% or more, respectively could be detected. The shelf life of the developed sensors was 30 and 90 days at 30 °C and 4-6 °C, respectively. In stored cow ghee samples, the response time of the sensors increased as the storage period of ghee samples increased. The cutoff limit to declare the sample of cow ghee as unadulterated was fixed to 60 min. Based on the response time of the sensor, the level of detection of vegetable oils in stored cow ghee was found to be 2.5%.

Physico-chemical properties of Khoa prepared from lactose hydrolyzed buffalo milk.

Lactose is a reducing sugar which is abundantly found in mammalian milk. Lactose intolerance affects more than 70% of the world population, being apparent by the absence of ß-galactosidase enzyme, thus leading to the inability to consume dairy products. In the present work, Khoa was prepared from lactose hydrolysed milk and its physico-chemical, textural and microbiological quality were examined during storage at 5-7 °C for 28 days. The sensory quality of low lactose Khoa was comparable with that of the control Khoa up to the 14th day of storage. Significant differences (p < 0.05) between the acidity, hydroxyl methyl furfural (HMF) content, lightness, redness, springiness, chewiness and hardness values of the low lactose Khoa and the control Khoa were observed. The standard plate count (SPC), coliform and yeast and mould counts of the low lactose Khoa were within Food safety and standards authority of India (FSSAI) standards throughout the 28 days of storage. Therefore, the low lactose Khoa developed in this study had different physicochemical properties from the control sample with better shelf life.

Use of lycopene as a natural antioxidant in extending the shelf-life of anhydrous cow milk fat.

Oxidative rancidity in anhydrous cow milk fat leads to reduction in its shelf life. Use of synthetic antioxidants is prevalent in dairy industry to prevent the development of rancidity. Keeping in view the increasing demand for natural additives, the present study was carried out to explore the potential of lycopene as a natural antioxidant in anhydrous cow milk fat. Lycopene at five different levels (30, 60, 90, 120 and 150 ppm) and butylated hydroxyl anisole (200 ppm), were incorporated in anhydrous cow milk fat. Potential of lycopene extract to enhance the shelf life of anhydrous cow milk fat was evaluated by measuring Free Fatty Acids, peroxide value, Thiobarbituric Acid value and color value during 12 months of storage at ambient conditions (30°C). Lycopene significantly (p<0.05) prevented the development of oxidative rancidity. Lycopene containing samples scored significantly higher in terms of sensory attributes as compared to control.

Colorimetric determination of melamine in milk using unmodified silver nanoparticles.

Melamine is nitrogen rich chemical compound used as an adulterant in dairy products by unscrupulous people to increase the apparent protein content. This incident prompted the researchers to develop simple methods for easy detection of melamine in food samples. In the present paper, we report a simple and sensitive colorimetric method for detection of melamine in milk based on silver nanoparticles. This method relies upon the principle that melamine causes the aggregation of silver nanoparticles, resulting in abrupt color change from yellow to red under optimized conditions. The concentration of melamine in adulterated sample can be quantitated by monitoring the absorption spectra of silver nanoparticles using ultraviolet-visible (UV-Vis) spectrometer. The present colorimetric method which utilizes silver nanoparticles of 35 nm can reliably detect melamine down to a concentration of 0.04 mg l(-1).

Colorimetric detection of melamine in milk by citrate-stabilized gold nanoparticles.

Here, we report a simple and sensitive colorimetric method for detection of melamine in milk using gold nanoparticles (AuNPs). AuNPs of 21-nm size were synthesized by the citrate reduction method. The method is based on the principle that the melamine causes the aggregation of AuNPs and, hence, the wine red color of AuNPs changes to blue or purple. This change in color can be visualized with the naked eye or an ultraviolet-visible (UV-Vis) spectrometer. Under optimized conditions, AuNPs are highly specific for melamine and can detect melamine down to a concentration of 0.05 mg L(-1).

Gene chromosomal organization and expression in cultured human neurons exposed to cocaine and HIV-1 proteins gp120 and tat: drug abuse and NeuroAIDS.

As a model for Neuropsychiatric dysfunction in NeuroAIDS due to HIV-1 infection and drug abuse, we analyzed gene expression in human neurons treated with cocaine and HIV-1 proteins tat and envelope (env). One-way ANOVA showed statistically significant genes among the treatment groups (p < or = 0.0005). The identified genes were then subjected to a "stepwise" analysis using a repeated measures ANOVA to discover genes with parallel response group profiles across the treatment conditions. These groups were then analyzed using a repeated measures ANOVA to assess treatment main effects and gene-by-treatment interactions within groups. One-way ANOVA produced 35 genes that were significantly associated across all treatment conditions. Factorial analysis of each gene found statistically significant differences: 30--tat, 17--cocaine, 10--env, 6--tat/env, 6--coc/env, and 4--coc/tat. Analyses across genes found three sets of four genes, one set of three genes, and three sets of two genes with parallel profiles. Identified genes had functions included signaling, immune related, and transcription control. The genes were not stochastically arranged on the chromosomes, were in proximity to each other, and to other genes involved in neuropsychiatric diseases. We hypothesize that these genes fall in transcriptionally isolated groups and that abused drugs and HIV-1 proteins trigger transcription overload, coerced expression that may result in damage to the chromosome's control and organization of chromatin transcription machinery.

Bioinformatics models in drug abuse and Neuro-AIDS: Using and developing databases.

The magnitude of the problems of drug abuse and Neuro-AIDS warrants the development of novel approaches for testing hypotheses in diagnosis and treatment ranging from cell culture models to developing databases. In this study, cultured neurons were treated with/without HIV-TAT, ENV, or cocaine in a 2x2x2 expression study design. RNA was purified, labeled, and expression data were produced and analyzed using ANOVA. Thus, we identified 35 genes that were significantly expressed across treatment conditions. A diagram is presented showing examples of molecular relationships involving a significantly expressed gene in the current study (SOX2). Also, we use this information to discuss examples of gene expression interactions as a means to portray significance and complexity of gene expression studies in Drug Abuse and Neuro-AIDS. Furthermore, we discuss here that critical interactions remain undetected, which may be unravelled by developing robust database systems containing large datasets and gleaned information from collaborating scientists . Hence, we are developing a public domain database we named The Agora database , that will served as a shared infrastructure to query, deposit, and review information related to drug abuse and dementias including Neuro-AIDS. A workflow of this database is also outlined in this paper.

HIV-associated dementia, Alzheimer's disease, multiple sclerosis, and schizophrenia: gene expression review.

RNA and protein gene expression technologies are revolutionizing our view and understanding of human diseases and enable us to analyze the concurrent expression patterns of large numbers of genes. These new technologies allow simultaneous study of thousands of genes and their changes in regulation and modulation patterns in relation to disease state, time, and tissue specificity. This review summarizes the application of this modern technology to four common neurological and psychiatric disorders: HIV-1-associated dementia, Alzheimer's disease, multiple sclerosis, and schizophrenia and is a first comparison of these diseases using this approach.