Hem Chandra Joshi

Valeriana wallichii DC a high-altitude medicinal plant is highly sensitive to drought stress which adversely impacts its physiological functions and root biomass. This study aimed to evaluate salicylic acid role in mitigating drought stress by assessing physiological and biochemical responses in V. wallichii. Plants were treated with foliar applications of SA at concentrations of 0.25, 0.50, 0.75 and 1.0 mM during vegetative and flowering stages. Physiological parameters such as photosynthetic rate, stomatal conductance, water use efficiency (WUE), intrinsic WUE (iWUE), carboxylation efficiency and biochemical traits including chlorophyll and carotenoid content were measured, alongside fresh and dry root biomass. Drought stress significantly reduced photosynthetic performance (Pn) (3.95 micro-mol CO2 per square meter per second at 25% FC), stomatal conductance, relative water content and root yield. SA application notably improved these traits. At 25% FC, 1.0 mM SA enhanced WUE (28.78), iWUE (642.37 micro-mol/mol) and fresh root weight (8.41 g). Under moderate drought (50% FC), 0.50 mM SA improved net photosynthesis (12.5 micro-mol CO2 per square meter per second, dry root weight (2.31 g) and chlorophyll content. SA treatments also stabilized membrane integrity and maintained higher chlorophyll fluorescence efficiency (Fv/Fm). These findings demonstrate that foliar application of SA enhances drought tolerance in V. wallichii by improving photosynthetic efficiency, water relations and root biomass. The study supports the strategic use of SA to improve the resilience and productivity of medicinal plants under drought stress conditions.

Mass spectrometry (MS) has revolutionized drug discovery, offering unparalleled accuracy in identifying and quantifying biomolecules. Recent advancements, such as high-resolution MS, have enhanced sensitivity and resolution, enabling precise molecular characterization. Techniques like liquid chromatography-MS (LC-MS) and quantitative MS, including multiple reaction monitoring (MRM), have improved drug metabolism and pharmacokinetics studies. Imaging mass spectrometry (IMS) allows for the spatial visualization of drug distribution in tissues, providing insights into drug efficacy and safety. These innovations accelerate the identification of drug candidates and their mechanisms, transforming pharmaceutical research and personalized medicine development.

The maintenance of sustainability and quantification of soil health in the rice–wheat system in the Himalayan tarai region is of utmost importance, and a long-term study can properly demonstrate what needs to be done to achieve this. The current study was conducted after the completion of a 29-year crop cycle in the rice–wheat system in 2015 at Pantnagar. Since the beginning of the experiment in 1984, various NPK combinations with or without Zn and farmyard manure (FYM) applications were maintained in a fixed layout along with an absolute control plot without any external nutrition. FYM at 5 mg ha⁻¹ and Zn at 5 kg ha⁻¹ were applied in only rice, and NPK-chemical fertilizers were applied both in rice and wheat. The results revealed that the application of N at 120 kg ha⁻¹ + P at 40 kg ha⁻¹ + K at 40 kg ha⁻¹ + FYM at 5 mg ha⁻¹ + Zn at 5 kg ha⁻¹ (NPK + FYM + Zn) resulted in the maximum attainment of long-term system productivity and the sustainable yield index (SYI), which were 22% higher than those with NPK application. NPK + FYM + Zn and NPK + FYM also improved the soil's overall physical, chemical, and biological parameters. Soil organic carbon, dehydrogenase activity, soil available P and K, phosphate solubilizing bacteria, and actinomycetes were found to be the most important soil quality parameters in Mollisols. From this study, it can be concluded that the application of the recommended NPK along with FYM and Zn can improve soil health and sustain the system productivity of the rice–wheat system in Mollisols of the Himalayan tarai region.

The main aim of this study is to determine the changes occurred in the antioxidant capacity and UV-protection capacity of rutin with a different redox-potential metal cation. The complexes were characterized by UV-Visible and IR spectroscopy. Rutin belongs to the flavonols and it is a glycoside form of quercetin. Chelate formation is a result of interaction of rutin with metal ions. The chelation of metals can be crucial in the prevention of radical generation, which damages target biomolecules. The interactions between flavonoids and transition metal ions to form complexes that prevent the participation of metal ions in free radical generating processes, thus exhibit an anti-oxidant behavior, metal-flavonoid complexes various biological and pharmacological activities. The coordination of Rutin (Rut) with Rut-Zr, Rut-Mo, Rut-Zn, Rut-Cu, Rut-Ni, Rut-Fe, Cit-Zn, Cit-Mo, Cit-Zr, Cit-Cu, Cit-Fe, and Cit-Ni may simulate the catalyzed centre of the hyperoxide dismutase in the metal coordinate structure, thus displayed the DPPH, hydroxyl radical scavenging activity, metal chelating, and nitric oxide (NO) and superoxide dismutase (SOD) radical scavenging. Therefore, the metal flavonoid complexes are very helpful in discovery and development of new drugs.

Over past few decades water pollution has become an issue of worldwide major concern. Availability of fresh water is decreasing gradually as water resource being limited and unevenly spread throughout the globe. Water pollution assessment and development of new and effective waste water treatment methods has become new a line of wide scope in scientific world. Meanwhile, with reference to past studies, we are well aware about the urban pollution that our crowded cities cause by dumping human excreta, household and industrial waste into river bodies but a question arise what is the contribution of rural area and agricultural activities in contaminating river bodies? And is the level of pollution due to agricultural and rural activities is significant with respect to urban pollution? Here we need to take account of biological processes such as bio-magnification and accelerated eutrophication that is caused by direct discharge of agricultural water containing chemical fertilizers and plant growth boosters during irrigation of agricultural field. A study has been conducted by us that involved, collecting water samples of river Rispana and river Bindal from area where agricultural activities are conducted and from areas of crowded city. We ran test like pH, pOH, conductivity, hardness, total dissolved salts, biochemical oxygen demand and chemical oxygen demand to estimate quality of water samples and results were compared as rural vs. urban pollution index.