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The content of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) increased in the roots of Salvia miltiorrhiza. The expression levels of genes encoding enzymes and the activities of key enzymes in the tanshinone biosynthesis pathway increased accordingly. The results showed that AP2/ERF TFs could positively regulate the biosynthesis of tanshinone in the roots of Salvia miltiorrhiza under salt stress.Temozolomide (TMZ) is a broad spectrum alkylating agent found effective in the treatment of glioblastoma multiforme, refractory anaplastic astrocytoma, and metastatic melanoma. The major drawback associated with TMZ is pH-dependent stability and short half-life. At physiological pH, it undergoes conversion to MTIC (methyltriazine imidazole carboxamide) and AIC (amino imidazole carboxamide), resulting in only 20-30% brain bioavailability. There is a need for an analytical method for the estimation of TMZ in stability samples and nanoformulations. In this research study, analytical methods were developed for the estimation of TMZ using two media pH 1.2 (0.1 N HCl) and pH 4.5 acetate buffer, which were validated for linearity, range, precision, accuracy, limit of detection, limit of quantification, and specificity as per ICH guidelines. The % RSD was found to be less then 2% indicating the reliability of the method. Further, the application of the developed methods was explored. The stability of TMZ in three pH conditions (1.2, 4.5, and 7.4) and the respective degradation rate kinetics was studied. Conversion of TMZ was found to follow first order kinetics with the conversion rate of 0.0011, 0.0011, and 0.0453 h-1 in pH 1.2, 4.5, and 7.4 respectively. The developed methods accurately estimated the TMZ concentration in lipid nanoformulation (liposomes) indicated by ~100% recovery. Acetate buffer (pH 4.5) was found to be an appropriate dissolution media for TMZ loaded lipid nanoformulations. The developed methods were found to be suitable for routine analysis, for the determination of drug stability and estimation of temozolomide in lipid nanoformulations.A novel and efficient non-azo formation based method was developed for trace sensing of mesalazine (MES), a pharmaceutical aromatic amine. MES was simply coupled with a Meldrum's activated furan (MAF) reagent via a furan ring opening reaction to form a colored product. The intense purple colored solution was detected at 575 nm. The reaction of MES with MAF was monitored by employing 1H NMR spectroscopy and mass spectrometry. In addition, density functional theory (DFT) was applied to optimize the structure of the colored product and its λmax (the wavelength of maximum absorbance) in dimethyl sulfoxide and water. The colored product was considered in three possible structures, and the most possible structures in dimethyl sulfoxide and in water were identified by employing the DFT calculations. Both of the most possible structures indicated only a local excitation in their λmax and no charge transfer was observed. However, one of the structures in dimethyl sulfoxide presented charge transfer properties occurrinwas successfully applied for detection of MES in various water matrices and pharmaceutical tablets.Recently, Krishnamoorthy and coworkers reported a new type of proton transfer, which was labeled as 'proton transfer triggered proton transfer', in 3,5-bis(2-hydroxypheny)-1H-1,2,4-triazole (bis-HPTA). read more In this work, the excited-state double proton transfer (ESDPT) mechanism and multiple fluorescent characteristics of bis-HPTA were investigated. Upon photo-excitation, the intramolecular hydrogen bonding strength changed and the electron density of bis-HPTA redistributed. These changes will affect the proton transfer process. In S0 state, the proton transfer processes of bis-HPTA were prohibited on the stepwise and concerted pathways. After vertical excitation to the S1 state, the ESIPT-II process was more likely to occur than the ESIPT-I process, which was contrary to the conclusion that the ESIPT-II process is blocked and the ESIPT-II process takes place after the ESIPT-I process proposed by Krishnamoorthy and coworkers. When the K2 tautomer was formed through the ESIPT-II process, the second proton transfer process on the stepwise pathway was prohibited. On another stepwise pathway, after the ESIPT-I process (form the K1 tautomer), the second proton transfer process should overcome a higher potential barrier than the ESIPT-I process to form ESDPT tautomer. On the concerted pathway, the bis-HPTA can synchronous transfer double protons to form the ESDPT tautomer. The ESDPT tautomer was unstable and immediately converted to the K2 tautomer via a barrierless reverse proton transfer process. Thus, the fluorescent maximum at 465 nm from the ESDPT tautomer reported by Krishnamoorthy and coworkers was ascribed to the K2 tautomer. Most of the fluorophores show dual fluorescent properties, while the bis-HPTA undergoing ESDPT process exhibited three well-separated fluorescent peaks, corresponding to its normal form (438 nm), K1 tautomer (462 nm) and K2 tautomer (450 nm), respectively.We have prepared high purity Zinc oxide (ZnO) nanoparticles (NPs) by solution combustion synthesis (SCS) method with the aid of lime juice extract. From powder X-ray diffraction (XRD) spectra, it is observed that the ZnO NPs possess single phase, hexagonal wurzite structure with sharp intense peak at (101) plane, agrees with the planes of SAED pattern. Further, the crystallite size is found to be around 18 nm. UV-Vis analysis shows strong UV absorbance band at 381 nm and PL measurements reveals the presence of strong UV emission at 347 nm along with few weak visible emissions. Optical studies infer the existence of lower recombination rate of electron-hole pair, influence the photocatalytic activity of ZnO. From XPS measurements, presence of oxygen rich states on surface are also confirmed (O 1 s states). The degradation performance and reusability of four different dyes (methylene blue (MB), methyl orange (MO), rhodamine B (RhB), Pararosaniline (PRA)) under UV and sunlight irradiations are carried out to illustrate the photo-catalytic activity in presence of a catalyst like ZnO NPs.