High Frequency Direct Plant Regeneration from Leaf and Petals of Cape Primrose (Streptocarpus)

A Chaudhury,JB Power,MR Davey 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.2

High frequency direct plant regeneration from leaf and petal explants was accomplished for the first time in Streptocarpus varieties. The shoot induction frequency varied with respect to the benzylaminopurine (BAP) concentration added to the Murashige and Skoog (MS) medium. MS medium with 0.5 mg l-¹ BAP exhibited the highest (69.9%) plant regeneration frequency with an average of 186 shoots per explant. A higher concentration of BAP inhibited shoot bud induction and plant regeneration along with necrosis of explants. Petal explants derived from the varieties 'Branwen' (pink and white) and 'Chorus Line' (violet and white) displayed plant regeneration frequency of 22.2 - 47.4% (within a total of 12 weeks) on MS medium containing 2.0 mg l-¹ α-naphthaleneacetic acid and 0.5 mg l-¹ BAP for 8 weeks followed by 4 weeks on MS medium with 1.0 mg l-¹ BAP. Scanning electron microscopy confirmed direct plant regeneration without callus. Regenerated plants from leaf explants with well-developed leaves and roots were hardened and successfully transferred to pots in glasshouse exhibiting 86% survival at the end of 4 - 6 weeks. Whereas, regenerated plants from flower petal explants upon transfer to pots in glasshouse exhibited 75 - 82% survival at the end of 4-6 weeks.

High Frequency Direct Plant Regeneration from Leaf and Petals of Cape Primrose (Streptocarpus)

Chaudhury, A.,Power, J.B.,Davey, M.R. 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.2

High frequency direct plant regeneration from leaf and petal explants was accomplished for the first time in Streptocarpus varieties. The shoot induction frequency varied with respect to the benzylaminopurine (BAP) concentration added to the Murashige and Skoog (MS) medium. MS medium with $0.5\;mg\;l^{-1}$ BAP exhibited the highest (69.9%) plant regeneration frequency with an average of 186 shoots per explant. A higher concentration of BAP inhibited shoot bud induction and plant regeneration along with necrosis of explants. Petal explants derived from the varieties 'Branwen' (pink and white) and 'Chorus Line' (violet and white) displayed plant regeneration frequency of 22.2-47.4% (within a total of 12 weeks) on MS medium containing $2.0\;mg\;l^{-1}$ $\alpha$-naphthaleneacetic acid and $0.5\;mg\;l^{-1}$ BAP for 8 weeks followed by 4 weeks on MS medium with $1.0\;mg\;l^{-1}$ BAP. Scanning electron microscopy confirmed direct plant regeneration without callus. Regenerated plants from leaf explants with well-developed leaves and roots were hardened and successfully transferred to pots in glasshouse exhibiting 86% survival at the end of 4-6 weeks. Whereas, regenerated plants from flower petal explants upon transfer to pots in glasshouse exhibited 75-82% survival at the end of 4-6 weeks.

Induction of Shikonin Production in Hairy Root Cultures Of Arnebia hispidissima via Agrobacterium rhizogenes-mediated Genetic Transformation

Chaudhury, Ashok,Pal, Minakshi 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.2

Data presented herein provides a rapid and efficient method for Agrobacterium rhizogenes-mediated genetic transformation of Arnebia hispidissima for hairy root cultures as well as for enhancing Shikonin production. Etiolated explants viz. shoot tip, nodal, leaf and internodal segments were co-cultivated with Agrobacterium rhizogenes for induction of hairy root. Among the various explants employed, leaf explant showed maximum 70.7% response followed by shoot tip 48.3%, nodal segment 38.7% and internodal segment 9.3%. Integration of Ri plasmid rolB gene in the transformed hairy root cultures was confirmed by PCR analysis using forward (FrolB) and reverse (RrolB) primers of rolB gene resulting in the amplification of 0 ~ 0.8 kb fragments. Medium compositions have been optimized for in vitro induction of Shikonin in hairy root cultures of Arnebia hispidissima. Hairy roots on hormone-free MS medium showed red spots in the older part of the tissues which turned white after a second subculture. Whereas hairy roots cultured on RC medium showed faster growth and produced large amount of Shikonin. The Shikonin content in transformed hairy root culture was estimated by recording absorbance at 620 nm and quantified against authentic sample of Shikonin. Shikonin content was estimated to be $0.85\;mg\;g^{-1}$ fresh weight of tissue at the end of the 50 days of culture. The results presented herein will help to design strategies for bridging the gap between ever increasing demand and supply of raw products necessary for obtaining Shikonin for cosmetic, dyeing, food, medicinal, and pharmaceutical industries.

Use of Speckle Tracking Echocardiography to Detect Induced Regional Strain Changes in the Murine Myocardium by Acoustic Radiation Force

Ankur Chaudhury,Austin Wanek,Devasena Ponnalagu,Harpreet Singh,Andrew Kohut 한국심초음파학회 2021 Journal of Cardiovascular Imaging (J Cardiovasc Im Vol.29 No.2

BACKGROUND: It is difficult to simulate the abnormal myocardial strain patterns caused by ischemic coronary artery disease (CAD) which are a precursor to heart failure (HF) within an animal model. Simulation of these strain changes could contribute to better understanding of the early formative stages of HF. This is especially important in investigating the poorly understood pathogenesis of heart failure with preserved ejection fraction (HFpEF). Here, we discuss delivery of high intensity focused ultrasound (HIFU) in a murine model to alter left ventricular (LV) regional longitudinal strain (RLS), and use of speckle tracking echocardiography to detect these changes. METHODS: HIFU pulses (pressure amplitude 1.7 MPa) were generated by amplifying a sinusoidal waveform from a function generator into a piezoelectric transducer. These pulses were then directed extracorporeally towards the anterior LV surface of C57BI6 mice during three time periods (early, mid, and late diastole). Speckle tracking echocardiography was then used to quantify changes in RLS within six segments of the LV. RESULTS: We observed an increase in LV RLS with acoustic augmentation during all three time periods. This augmentation was most prominent near the anterior apical region in early diastole and near the posterior basilar region during late diastole. CONCLUSIONS: Our findings demonstrate the application of HIFU to non-invasively induce changes in RLS within a murine model. Our results also reflect the capability of speckle tracking echocardiography to analyze and quantify these changes. These findings represent the first demonstration of ultrasound-induced augmentation in LV RLS within a small animal model.

Population status, habitat preference, and nesting characteristics of black-headed ibis Threskiornis melanocephalus Latham, 1790 in southern Rajasthan, India

Sunil Chaudhury,Vijay Kumar Koli 국립중앙과학관 2018 Journal of Asia-Pacific Biodiversity Vol.11 No.2

The black-headed ibis Threskiornis melanocephalus is a medium sized (65–75 cm long) wading, nomadic Ciconiiform waterbird, gregariously frequenting shallow habitats. It is wide-ranging species distributed across the Asian continent and categorized as “Near Threatened” by IUCN (International Union for Conservation of Nature) because of decreasing population status from the last few decades. The present work describes the current population status, habitat preference in response to seasonal variation, and nesting characteristics of black-headed ibis T. melanocephalus in southern Rajasthan, India. Different surveys were performed in the study area at different temporal and spatial scales to assess different aspects. A total of 580 individuals (496 adults and 84 juveniles) were recorded during 2016, while 643 individuals (547 adults and 96 juvenile) in 2017. Juveniles represented 14.7% of the total population. The overall adult–juvenile ratio was 0.16 in 2016 and 0.17 in 2017. The encountered birds were found not significantly different seasonally in distinct microhabitats in both years (p < 0.05); highest number was recorded in seasonal wetlands. Nesting sites were recorded in two districts (i.e. Udaipur and Dungarpur) along with eight other waterbird species. Cattle egrets Bubulcus ibis was the most commonly associated nesting species, while babul Acacia nilotica and vilayati babul Prosopis juliflora were the most preferred nesting tree species.

Induction of Shikonin Production in Hairy Root Cultures of Arnebia hispidissima via Agrobacterium rhizogenes-mediated Genetic Transformation

Ashok Chaudhury,Minakshi Pal 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.2

Data presented herein provides a rapid and efficient method for Agrobacterium rhizogenes-mediated genetic transformation of Arnebia hispidissima for hairy root cultures as well as for enhancing Shikonin production. Etiolated explants viz. shoot tip, nodal,leaf and internodal segments were co-cultivated with Agrobacterium rhizogenes for induction of hairy root. Among the various explants employed, leaf explant showed maximum 70.7% response followed by shoot tip 48.3%, nodal segment 38.7% and internodal segment 9.3%. Integration of Ri plasmid rolB gene in the transformed hairy root cultures was confirmed by PCR analysis using forward (FrolB) and reverse (RrolB) primers of rolB gene resulting in the amplification of 0 ~ 0.8 kb fragments. Medium compositions have been optimized for in vitro induction of Shikonin in hairy root cultures of Arnebia hispidissima. Hairy roots on hormonefree MS medium showed red spots in the older part of the tissues which turned white after a second subculture. Whereas hairy roots cultured on RC medium showed faster growth and produced large amount of Shikonin. The Shikonin content in transformed hairy root culture was estimated by recording absorbance at 620 nm and quantified against authentic sample of Shikonin. Shikonin content was estimated to be 0.85 mg g-1 fresh weight of tissue at the end of the 50 days of culture. The results presented herein will help to design strategies for bridging the gap between ever increasing demand and supply of raw products necessary for obtaining Shikonin for cosmetic, dyeing, food, medicinal, and pharmaceutical industries.

Fluorescence spectroscopic study to characterize and monitor TEOS based sol-gel process for development of optical biosensors

N.K.Chaudhury,R.Bhardwaj,B.M.Murari 한국물리학회 2003 Current Applied Physics Vol.3 No.2, 3

Development of optical biosensors is an active area of research in the field of medical technology. Solgel matrices made fromalkoxide silicates,tetraethyl orthosilicate (TEOS) appear to be suitable glassy host matrix for the sensing system. However,themajor problem in the TEOS based solgel matrices is stability. So it is important to study dopantmatrix interaction as a function of time. In the present study,we report uorescence emission and excited state lifetime measurements on uorescent probes entrappedin TEOS solgel for monitoring the physico-chemical processes for characterization and monitoring of local environment (pores) ofviz.,Hoechst 33258 (H258) and pyranine (PY) were used. Solgels containing these probes were prepared at pH¼ 6:0 and thephysical and spectroscopic parameters were monitored as a function of storage time (days). The emission intensity from entrappedH258 has shown relatively higher extent of decrease during aging. The excited state uorescence lifetime measurements on theseprobes depicted single exponential decay component at 5.4 ns (PY) and 3.6 ns (H258) in fresh solgels. After a few days of storageprobe molecule PY. Further conrmation of multicomponents decay was obtained by distribution analysis of lifetime of H258where an increase in width of mean lifetime was observed with storage whereas no such change was indicated from PY. Thus itappears that H258 is a better probe molecule for characterizing and monitoring local environment of pores in solgel.. 2002 Elsevier Science B.V. All rights reserved.

Dissolution kinetics of chromite overburden by using mineral acids

Gautam Roy Chaudhury,P. K. Swain,L. B. Sukla 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.6

different mineral acids were used to determine the kinetics of dissolution of Ni and Fe from chromiteas acid concentration, pulp density, temperature and particlesize. Both Fe and Ni dissolution followed 1st order irreversible kinetics. The activation energy was also measured. Uni-fied rate equations were established for Ni and Fe dissolution for two different mineral acids, HCl and H2SO4. The dis-solution reaction was observed to follow diffusion control-dense-constant size spherical particles.

Analysis of prismatic springs of non-circular coil shape and non-prismatic springs of circular coil shape by analytical and finite element methods

Arkadeep Narayan Chaudhury,Debasis Datta 한국CDE학회 2017 Journal of computational design and engineering Vol.4 No.3

This paper presents a methodology for designing prismatic springs of non-circular coil shape and nonprismatic springs of circular coil shape using analytical and numerical methods. To start with, simple analytical formulations for obtaining the axial deformation of the springs under axial load have been demonstrated. Next, the processes of obtaining CAD models of the springs and their subsequent finite element analysis (FEA) in commercial softwares have been outlined. In the third part, the different springs have been compared with a common cylindrical spring and their merits compared to a common spring have been demonstrated. Next, a fairly accurate analytical formulation (with maximum error of ?7–8%) for obtaining the value and location of maximum shear stress for all the springs has been demonstrated. Next, two aspects of non-prismatic springs under dynamic loads, viz. damping introduced in a vibrating system and contribution of the spring to the equivalent mass in a one dimensional vibrating spring mass system due to shape of the spring have been discussed. The last part involves an analytical formulation for the linear elastic buckling of two springs with circular coil shapes. For the majority of the work, emphasis has been on obtaining and using closed form analytical expressions for different quantities while numerical techniques such as FEA have been used for validation of the same.

High Frequency Direct Plant Regeneration, Micropropagation and Shikonin Induction in Arnebia hispidissima

Pal, Minakshi,Chaudhury, Ashok 한국작물학회 2010 Journal of crop science and biotechnology Vol.13 No.1

The data presented herein reports a rapid and efficient method for direct plant regeneration at high frequency without intervening callus formation from shoot tip (93%) and nodal segment (60%) cultured on MS media supplemented with 0.5 mg $1^{-1}$ KIN, 0.25 mg $1^{-1}$ BAP, 0.1 mg $1^{-1}$ IAA and 100 mg $1^{-1}$ CH. Conversely, leaf and internodal explants were poorly responsive. Adventitious shoot buds arose not only from the cut ends but all along the surface of the explants leading to the formation of clusters with multiple shoots. Multiple shoots upon transfer to MS media supplemented with 2.0 mg $1^{-1}$ IBA induced efficient rooting (80%). In vitro flowering was observed when tissue culture-raised plantlets were maintained for extended period in culture. Shikonin was induced in roots of regenerated plants which often exudates in the culture medium was quantified spectrophotometerically by recording absorbance at 620 nm and estimated to be 0.50 mg $g^{-1}$ fresh weight of tissue at the end of the 50 days of culture. The regenerated plants were successfully acclimatized, hardened, and transferred to soil in green house for micropropagation. The protocol developed here will be very useful for the supply of Arnebia hispidissima all year as a raw product necessary for obtaining Shikonin for the cosmetic, dyeing, food, and pharmaceutical industries.