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The study aims to monitor pesticide and antibacterial drug residues in food of animal origin namely eggs, chicken, chevon and cow milk using two modified multi-residue analytical methods for simultaneous detection and quantification of thirteen pesticides with gas chromatography-electron capture detector (GC-ECD) and four antibacterial drugs with high performance liquid chromatography–diode array detector (HPLC-DAD). A total of 462 egg, 503 chicken, 575 chevon and 570 milk samples were collected from the local markets, dairy farms and households in twelve districts of West Bengal and four districts of Odisha, India. Samples were procured in summer and winter season. The validation of the method included the determination of limit of detection, limit of quantification, linearity, accuracy and precision and an inter- and intra-day assay of the method. Good linearity was obtained (r2 > 0.99), the recovery % ranged from 85.07 to 93.53% for antibacterial drugs and from 82.0 to 99.47% for pesticides, inter-assay and intra-assay variability were below 10 and 15% and repeatability was

Antitumor potential of a 1,4-dihydropyridine derivative (DHP-8) has been successfully studied previously in a number of cancer cell lines including the human melanoma cells, A375. In order to validate its anticancer activity, DMBA induced tumor in Swiss Albino mice was considered for this study. DMBA causes skin carcinoma in murine systems and is an important in vivo model for evaluating the efficacy of any new chemical entity against skin cancer. Topical administration of DHP-8 at the dose rate of 33.3 and 50.0 mg/kg body weight showed a significant reduction in tumor parameters. It also prevented the progression and differentiation of squamous cell carcinoma, as evidenced from histopathological studies. Immunohistochemical analysis for the expression of Ki67 indicated that it also reduced cancer cell proliferation. Additionally, it induced apoptosis in the tumor cells by activation of Caspase3. Our results indicated that DHP-8 efficiently attenuated DMBA induced tumor progression and it could be a potent therapeutic agent for skin cancer treatment.

Leaf senescence is an intricate process that requires time-dependent transitions of cellular physiology and metabolism. It is a coordinated process that includes interaction between cells and organs. It requires the combined functions of hundreds of genes, enzymes, and signaling pathways that desegregate various endogenous and exogenous signals, controlled by many layers of regulation. The timing of senescence is affected by developmental and environmental signals throughout the leaf life span. In plants, the process involves morphological, biochemical, and molecular changes that permit the remobilization of nutrients in a well-synchronized way from senescence-affected leaves toward the growing leaves, developing fruits, seeds, and buds. Significant research has been done to understand leaf senescence by means of genetic and molecular studies. Recently developed omics techniques help in the identification, isolation, and characterization of senescence-associated genes (SAGs) and functions of relative proteins in the last few years. The functioning of SAGs is regulated genetically and epigenetically by plant hormones, nutrients, protein degradation, and nitrogen mobilization. Hormonal regulation and sugar signaling play a central role in leaf senescence, which can influence the plant growth, stress responses and timing of leaf senescence. All known phytohormones to date affect leaf senescence by some means, but the functions of ethylene and cytokinin in the process still need to be explored. It has been hard to study the role of various hormones in regulating the initiation and development of leaf senescence. Some studies have proved that phytohormones play an important role in delaying and accelerating leaf senescence by declining or increasing their levels and site of action. This chapter includes information about the potential biochemical and molecular events that take place during developmental senescence and the prominent roles of hormones that involve developmental aging, initiation, and progression of senescence.

Terpenoids are the most functionally and structurally varied group of plant metabolites. These are synthesized in all organisms but are especially abundant and diverse in plants. Despite their diversity of functions and structures, all terpenoids are derived from the common five-carbon (C5) building unit, isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) through MEP pathway in all living organisms. The MEP pathway synthesizes IPP and DMAPP in plastids in plants and more complex terpenoids are usually formed by “head-to-tail” or “head-to-head” addition of isoprene units. Monoterpene indole alkaloids (MIAs) are one of important class of terpenoids which are C10 terpenoids, consisting of two isoprene units and are the components of more than 2000 defined compounds. These are a large group of plant-derived natural products with a range of pharmacological properties. These MIAs are potent drugs, such as anticancer, antimalarial, and antiarrhythmic agents. These MIAs have been found in eight different plant families, being most common in Apocynaceae, Rubiaceae, and Loganiaceae. Madagascar periwinkle, Catharanthus roseus, the best-characterized MIA-producing plant species, is the source of the valuable MIAs. It has approximately 130 alkaloids of indole group, out of which 25 are dimeric in nature. Some of these compounds have important medicinal properties such as anticancerous property (vincristine and vinblastine) and antiarrhythmic property (ajmalicine and serpentine). In the present chapter, molecular network of monoterpene indole alkaloids (MIAs) signaling in plants with reference to Catharanthus roseus (L.) G. Don has been reviewed.