Browsing by Author "Chakraborty, Usha"
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Item Open Access Biochemical characterization of temperature stress response of Cicer Arietinum L and induction of thermotolerance(University of North Bengal, 2006) Tongden, Cyaria; Chakraborty, UshaItem Open Access Biochemical responses of maize (Zea mays L.) to water stress(University of North Bengal, 2013-10) Lama, Rohini; Chakraborty, UshaItem Open Access Characterisation of active principles found in some ethnomedicinal plants(University of North Bengal, 2008) Das, Hariswami; Chakraborty, UshaItem Open Access Comparative analysis of antioxidant activities and phytochemical properties of some culinary herbs(University of North Bengal, 2016-03) Dev Chaudhuri, Sandip; Shah, Anju; Chakraborty, UshaThe present work aimed to evaluate the antioxidant activities as well as phytochemical analysis of leaf extracts of some commonly used leafy spices such as Murraya koenigi (Mk), Coriandrum sativum (Cs), Trigonella foenum-graecum (Tfg) and Mentha x piperita (Mp). Lyophilised plant extracts (LPEs) were obtained by hot water extraction (HWE) process followed by rotavap and lyophilisation. Among the herbs tested, Mk showed the highest antioxidant activity in DPPH Scavenging (77.35 % mg-1 of LPE), superoxide anion radical scavenging (60.21 % mg-1 of LPE) and hydrogen peroxide scavenging (57.21 % mg-1 of LPE) model. Tfg showed least activity in DPPH scavenging (33.15 % mg-1 of LPE) and superoxide anion radical scavenging (25.36 % mg-1 of LPE) assay while Cs had the least activity in hydrogen peroxide scavenging (43.70 % mg-1 of LPE) system. Phytochemical investigations revealed the presence of major primary and secondary metabolites. MK possessed highest amount of phenolics (5.70 mg GAE g-1 of LPE), soluble sugars (68.18 mg GLE g-1 of FTW) and proteins (69.84 mg BSAE g-1 of FTW) and plant pigments (total chlorophyll 6.22 mg g-1 of FTW and total carotenoid 0.19 μg g-1 of FTW) among the herbs. SDS-PAGE and HPLC finger printing had been performed for analysis of protein patterns and phenolic compounds respectively. In conclusion, addition of culinary herbs and leafy spices that show high to moderate antioxidant activity with an excellent amount of phytochemicals in dietary items would go a long way in assuring human health and wellness as well as enhancement of the disease fighting capacity against oxidative stress related disorders.Item Open Access Comparative study of basal thermo tolerant attributes in tolerant and susceptible wheat cultivars(University of North Bengal, 2019-03) Sarkar, Jayanwita; Chakraborty, Usha; Chakraborty, BishwanathTwo wheat cultivars, viz. C306 and HT41, have been evaluated for their responses to heat stress in terms of some biochemical and physiological attributes. During the exposure to high temperature (40°C for 6 and 12 h), a significant reduction in RWC and FW was recorded in HT41 which was also associated with heat susceptibility. The detrimental effects of high temperature were also apparent in terms of lipid peroxidation, chlorophyll content, H2O2 generation and electrolyte leakage and these were more pronounced in HT 41. Accumulation of osmolytes like proline, total sugar increased due to heat injury and also varied between the two cultivars. In this present study evaluation and analysis of these biochemical and physiological characters under heat stress could unravel the mechanism of basal thermotolerance and thus might be useful as genetic stock to develop wheat tolerant varieties.Item Open Access Development of an easy and efficient technique for cultivation of different species of Pleurotus(University of North Bengal, 2014-03) Roy, Somnath; Barman, Shibu; Chakraborty, Usha; Chakraborty, BishwanathOyster mushroom is one of the most popular mushrooms in North Bengal and a large number of growers are now cultivating oyster mushroom throughout the year. There are mainly three species of oyster mushroom (Pleurotus ostreatus, P. sajor-caju, P florida) which are being cultivated in this region. Out of these three mushrooms, P. ostreatus and P. sajor-caju are generally cultivated in summer as it grows in a temperature between 25-33C while P. florida is generally cultivated during winter as it requires 15-20°C for its growth. Bottle cultivation is a technique of mushroom cultivation where it reduces the cost of plastic bags and the plastic bottles can be recycled. Besides plastic bottles, other used laboratory chemical plastic containers were also tested and gave good results.Item Open Access Influence of drought and salinity on metabolic processes in different wheat varieties(University of North Bengal, 2013-11) Pradhan, Bhumika; Chakraborty, UshaItem Open Access Medicinal properties of some dietary herbs and spices(University of North Bengal, 2017) Chaudhuri, Sandip Dev; Chakraborty, UshaItem Open Access Oxidative stress signaling in soybean and lentil under temperature stress induction of thermotolerance(University of North Bengal, 2011) Pradhan, Deepti; Chakraborty, UshaItem Open Access Phytochemical analysis of some ferns with reference to their antioxidant, hypoglycemic and antimicrobial activities(University of North Bengal, 2016) Jaishee, Nishika; Chakraborty, UshaItem Open Access RAPD analysis and rDNA gene sequence based phylogeny of Bipolaris sorokiniana, a spot blotch pathogen of sorghum(University of North Bengal, 2019-03) Bhattacharjee, Priyanka; Sen, Armab; Chakraborty, Usha; Chakraborty, BiswanathSorghum [Sorghum bicolor (L) Moench] is the one of the most important cereal crops in the world. It is the staple food grain for over 750 million people who live in the semi-arid tropics of Africa, Asia, and Latin America. Global pro-duction of sorghum is currently estimated to be 57.6 million tonnes, with Asian countries contributing 20% of the total production. Within Asia, India is the largest producer of sorghum grain. Recently there have been severe signs of sorghum decline caused by Bipolaris sorokiniana resulting in decreased production of sorghum in villages of Kalimpong and Darjeeling. In the present study, initially, several strains of the fungus were isolated from diseased leaves of Sorghum bicolor and Triticum aestivum which were morphologically identified as Bipolaris sorokiniana. Genomic DNA of B. sorokiniana isolated from infected leaves was purified and PCR amplification of 18s rDNA was done using specific primers. Amplified product (1190 bp) was sequenced and aligned against ex-type strain sequences of B. sorokiniana from NCBI GenBank using BLAST and phylogenetic analysis was done using MEGA4 software. RAPD PCR analysis and DGGE analysis of amplified genomic DNA were done. The evolutionary history was inferred using the UPGMA method. Amplification of ITS region of the rDNA can be considered as a rapid technique for identifying pathogens successfully in all cases.Item Open Access Reactive oxygen species and environmental stresses(University of North Bengal, 2007-03) Chakraborty, UshaReactive oxygen species (ROS) include oxygen ions, free radicals and peroxides both inorganic and organic. They are generally very small molecules and are highly reactive due to the presence of unpaired valence shell electrons. ROSs form as a natural byproduct of the normal metabolism of oxygen and have important roles in cell signaling. While ROS have the potential to cause oxidative damage to cells during environmental stress, recent studies have shown that ROS play a key role in plants as signal transduction molecules involved in mediating responses to pathogen infection, environmental stresses, programmed cell death and developmental stimuli. The rapid increase in ROS production, referred to as 'the oxidative burst', was shown to be essential for many of these processes, and genetic studies have shown that respiratory burst oxidase homolog (Rboh) genes, encoding NADPH oxidases, are the main producers of signal transduction-associated ROS in cells during these processes.Item Open Access Screening of free-living bacteria from the rhizosphere of Jute for their multiple plant growth promoting and antagonistic activity against phytopathogens(University of North Bengal, 2015-03) Majumdar, Sukanta; Chakraborty, UshaPresent investigation was undertaken to screen the PGPR isolates from the rhizosphere of Jute for their plant growth promoting and antagonistic activities in the view of an alternative way to chemical fertilizer and hazardous fungicides. A total 76 isolates were isolated from different parts of northern West Bengal and screened for their antagonistic activity against Macrophomiona phaseolina. Most promising five isolates were selected for further study and screened for other plant growth promoting and lytic enzyme producing abilities. Out of these, two isolates were Gram positive and rest three Gram negative. All five isolates exhibited several plant growth promoting activities. All five isolates showed IAA and ammonia production whereas four out five showed phosphate solubilization activity. Three PGPR strains exhibited siderophore production and only one isolate showed cyanide production ability. Among the lytic enzymes, chitinase was produced by three isolates. Among them B-3 showed highest degree of chitinase production. Protease was also produced by four strains but amylase and B-1,4-glucanase activity showed by only one isolate, Act-6. Two isolates B-3 and Acti-6 showed considerable amount of antagonistic activity against three phytopathogens Macrophomina phaseolina, Fusarium oysporum, and F. semitectum suggesting that Acti-6 and B-3 showed several attributes to be the potent strains of PGPR and can be used as biofertilizer as well as biocontrol agents.Item Open Access Serological detection of sphaerostible repens B. and Br. causing violet root rot disease of tea and its management(University of North Bengal, 2002) Das, Jyotsna; Chakraborty, UshaItem Open Access Studies on anthropogenic stresses in tea (Camellia Sinensis (L) O. Kuntze)(University of North Bengal, 2009) Saha, Gargi; Chakraborty, UshaItem Open Access Studies on bio-degradation of pulses by storage fungi(University of North Bengal, 2005) De, Paramita; Chakraborty, UshaItem Open Access Studies on heavy metal stresses in Okra Abelmoschus Esculentus (L) Moench(University of North Bengal, 2007) Lahon, Belinda; Chakraborty, UshaItem Open Access Studies on the Biology of Brown blight disease of Tea, Camellia sinences(L.) O, Kuntze with special reference to the factors effecting its in incidence(University of North Bengal, 2000) Datta, Shraboni; Chakraborty, UshaItem Open Access Studies on the Brown Blight disease of tea Camellia sinensis L. (O.) Kuntze cause by Glomerella cingulata (stoneman) Spauld. & Schrenk. and its interaction with phylloplane microorganisms(University of North Bengal, 1995) Das, Gouri; Chakraborty, Usha