Browsing by Author "Archana Prasad"

Now showing 1 - 13 of 13

A Literature Update on Strategies for Harnessing and Conserving the Bioactive Phytochemicals from Tinospora cordifolia: Current Status, Challenges, and Future Prospects
(Springer Nature, 2023) Archana Prasad; Preeti Patel; Mamta Kumari; Gauri Saxena; Debasis Chakrabarty; Satya Shila Singh
Tinospora cordifolia(Family Menispermaceae), commonly known as “Guduchi,” is an extensively used medicinal plant in modern as well as traditional Ayurvedic systems of medicine. The constitutive occurrence of various bioactive constituents such as terpenes, alkaloids, glycosides, aliphatic compounds, and flavonoids attributes to its inexplicable efficacy towards various chronic ailments due to its antidiabetic, anti-inflammatory, hepatoprotective, immunomodulatory, antiperiodic, antileprotic, antispasmodic, antiarthritic, antioxidant, antistress, antimalarial, and antineoplastic activities. The whole plant parts viz. roots, stem, and leaves act as a repository of these important bioactive constituents and are utilized in the preparation of various pharmaceutical, nutraceutical, and cosmeceutical formulations. A scan of the published literature survey on T. cordifolia clearly indicates that an array of reviews is available on the phytochemical and pharmacological activities of this plant, but systematic compilation for its conventional and nonconventional mode of propagation, conservation, and strategies for the sustainable production of its metabolites is still lacking. Hence, the present review is an attempt in this direction focused on understanding the different means of propagation that act as an alternative platform for strategizing the production as well as the conservation of the bioactive constituents of this important medicinal plant. A critical evaluation of the future implications as well as breakthrough for the commercialization of T. cordifolia is also discussed. ©The Editor(s)(if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023
Abiotic Stress-Induced Epigenetic Modifications in Plants
(Springer Nature, 2024) Preeti Patel; Archana Prasad; Satya Shila Singh
Plants are constantly exposed to various unfavourable environmental conditions, which drive them to adopt several survival strategies including epigenetic modifications. These modifications correlate with the expression of genes via transcriptional regulation deprived of altering the DNA sequences. Stress tolerance in plants is significantly conferred by epigenetic changes including small RNA- mediated silencing, histone alterations, and DNA methylation. These modifications also facilitate long-term stress tolerance adaptation via persistent gene regulation or transgenerational inheritance. Various advantageous traits in crop improvement are governed by the heritable epigenetic changes as epialleles. Recently, many studies emphasized the mechanism and regulation of epigenetic modifications adopted by plants in response to different stress. These modifications play an important role in governing stress tolerance, acclimatization, adaptation, and evolution practices. This chapter emphasizes the abiotic stress-induced epigenetic modifications and their regulation in plants. Further, the exploration of epigenetic changes leading to the production of stress-tolerant crops is also discussed. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
Biotic elicitor–induced changes in growth, antioxidative defense, and metabolites in an improved prickleless Solanum viarum
(Springer Science and Business Media Deutschland GmbH, 2022) Archana Prasad; Preeti Patel; Abhishek Niranjan; Aradhana Mishra; Gauri Saxena; Satya Shila Singh; Debasis Chakrabarty
Abstract: Solanum viarum serves as a raw material for the steroidal drug industry due to its alkaloid and glycoalkaloid content. Elicitation is well-known for measuring the increase in the yield of bioactive compounds in in vitro cultures. The current study was performed for the accumulation of metabolites viz. solasodine, solanidine, and α-solanine in S. viarum culture using microbial-based elicitors added in 1%, 3%, 5%, and 7% on 25th and 35th day of culture period and harvested on 45th and 50th days of culture cycle. The treatment of 3% Trichoderma reesei and Bacillus tequilensis culture filtrate (CF) significantly increased biomass, alkaloids/glycoalkaloid content, and yield in S. viarum. T. reesei was found to be the best treatment for enhanced growth (GI = 11.65) and glycoalkaloid yield (2.54 mg DW plant−1) after the 50th day of the culture cycle when added on the 25th day. The abundance of gene transcripts involved in the biosynthesis of alkaloids/glycoalkaloids, revealed by quantitative real-time PCR expression analysis correlates with the accumulation of their respective metabolites in elicited plants. Biochemical analysis shows that elicited plants inhibited oxidative damage caused by reactive oxygen species by activating enzymes (superoxide dismutase and ascorbate peroxidase) as well as non-enzymatic antioxidant mechanisms (alkaloids, total phenols, total flavonoids, carotenoids, and proline). The findings of this study clearly demonstrate that the application of T. reesei and B. tequilensis CF at a specific dose and time significantly improve biomass as well as upregulates the metabolite biosynthetic pathway in an important medicinal plant- S. viarum. Key points: • Biotic elicitors stimulated the alkaloids/glycoalkaloid content in S. viarum plant cultures. • T. reesei was found to be most efficient for enhancing the growth and alkaloids content. • Elicited plants activate ROS based-defense mechanism to overcome oxidative damage. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Depth of soil compaction predominantly affects rice yield reduction by reproductive-stage drought at varietal screening sites in Bangladesh, India, and Nepal
(Springer International Publishing, 2017) Suresh Prasad Singh; Abhinav Jain; M.S. Anantha; Santosh Tripathi; Subarna Sharma; Santosh Kumar; Archana Prasad; Bhawana Sharma; Biswajit Karmakar; Rudra Bhattarai; Sankar Prasad Das; Shravan K. Singh; Vinay Shenoy; R. Chandra Babu; S. Robin; Padmini Swain; J.L. Dwivedi; Ram Baran Yadaw; Nimai P. Mandal; T. Ram; Krishna Kumar Mishra; S.B. Verulkar; Tamal Aditya; Krishna Prasad; Puvvada Perraju; Ram Krishna Mahato; Sheetal Sharma; K. Anitha Raman; Arvind Kumar; Amelia Henry
Aims: Drought is the major constraint to rainfed rice productivity in South Asia, but few reports provide detailed characterization of the soil properties related to drought stress severity in the region. The aim of the study was to provide a compilation of drought breeding network sites and their respective levels of drought stress, and to relate soil parameters with yield reduction by drought. Methods: This study characterized levels of drought stress and soil nutrient and physical properties at 18 geographically distributed research station sites involved in rice varietal screening in Bangladesh, India, and Nepal, as well as at farmers’ fields located near the research stations. Results: Based on soil resistance to penetration profiles, a hardpan was surprisingly absent at about half of the sites characterized. Significant relationships of depth of compaction and yield reduction by drought indicated the effects of soil puddling on susceptibility to cracking, rather than water retention by hardpans, on plant water availability in this region. The main difference between research stations and nearby farmers’ fields was in terms of soil compaction. Conclusions: These results present an initiative for understanding the range of severities of reproductive-stage drought stress in drought-prone rainfed lowland rice-growing areas in South Asia. © 2017, The Author(s).
Genotype-dependent and temperature-induced modulation of secondary metabolites, antioxidative defense and gene expression profile in Solanum viarum Dunal
(Elsevier B.V., 2022) Preeti Patel; Archana Prasad; Dipali Srivastava; Abhishek Niranjan; Gauri Saxena; Satya Shila Singh; Pratibha Misra; Debasis Chakrabarty
The medicinal plant, Solanum viarum Dunal includes a number of compounds with important pharmacological effects. The effect of temperature (heat and cold) stress on growth, secondary metabolite levels and defense mechanism in two genotypes (prickled and prickleless) of S. viarum was evaluated. The two thermal regimes (4 °C for cold and 35 °C for heat stress) were found to be the most optimum for the accumulation of metabolites (steroidal alkaloids and glycoalkaloids, phenolic acids as well as flavonoids). Prickleless genotype showed 4.08 and 1.51 fold higher total alkaloids/glycoalkaloid content at 35 °C and 4 °C temperatures respectively, in comparison with prickled plants. Prickleless plants also registered 2.03 and 2.28 higher fresh and dry biomass accumulation respectively, under cold stress over the control plants. The accretion of phenolic and flavonoid compounds under heat and cold stress is mainly contributed by gallic and ferulic acid in both the genotypes. The quantitative real-time PCR expression analysis showed the abundance of gene transcript involve in the biosynthesis of alkaloids/glycoalkaloid and phenolics/flavonoids that corroborates with the accumulation of their respective metabolites in prickleless plants under temperature stress. Results revealed that the prickleless plants inhibiting the reactive oxygen species (ROS) mediated oxidative damage by activating the enzymatic (superoxide dismutase, peroxidase, catalase and ascorbate peroxidase) and non-enzymatic (alkaloids, phenols, flavonoids, carotenoids and proline) antioxidants mechanism that confirms its efficiency to tolerate thermal stress under both the thermal regimes. The overall result showed that the prickleless genotype served as a better accumulator of biomass, secondary metabolites with an improved antioxidative mechanism in comparison to prickled genotype. Our findings suggest that thermal stress responses differ significantly between genotypes, emphasizing the necessity of maintaining genotypic diversity in adaptive evolution as in the context of global warming and climate change. The present study also opens the possibility of exploiting improved prickleless genotype of S. viarum as a potential system that can be cultivated under different temperature stress conditions to attain the phytopharmaceutical benefits. © 2021 Elsevier B.V.
Glandular trichomes: Bio-cell factories of plant secondary metabolites
(Bentham Science Publishers, 2024) Pragya Shukla; Archana Prasad; Khushboo Chawda; Gauri Saxena; Kapil D. Pandey; Debasis Chakrabarty
Trichomes are specialised epidermal outgrowth that is present on the aerial parts of plants. On the basis of morphological and cellular variation, they are categorized into non-glandular trichomes (NGTs) and glandular trichomes (GTs). NGTs are known to be involved in the protective and defensive roles that attribute to provide structural and chemical corroboration to form specialized groups of secondary metabolites. GTs are specialized micro-organs that are considered factories for the biosynthesis of a considerable amount of different classes of bioactive metabolites. Conventionally these glandular and non-glandular trichomes are known for their protective roles against different biotic and abiotic stresses. Recently, they have attracted the interest of various researchers as a specialized organ for the production of various bioactive molecules of high pharmaceutical and commercial values. The major groups of secondary metabolites such as terpenoids, flavonoids, phenylpropanes, methyl ketones, acyl sugars and defensive proteins are reported in the trichomes of different plant species. However, the conception of the molecular regulation of their biosynthesis, storage and distribution during the development of trichomes is scattered. This review compiles structural and functional aspects of GTs and NGTs along with the molecular mechanism regulated for the production of secondary metabolite in these specialized organs. In addition, the role of several bio-physical parameters that affect the trichome biochemistry, which either directly or indirectly influence the biosynthesis of secondary metabolite, will also be focussed. The systemized knowledge of trichome biology, secondary metabolite pathway modulation and metabolic engineering at one platform will be helpful to explore recent advances in the field of trichome engineering in many medicinally important plants. © 2024 Bentham Science Publishers. All rights reserved.
Growth, phytochemical and gene expression changes related to the secondary metabolite synthesis of Solanum viarum Dunal
(Elsevier B.V., 2021) Preeti Patel; Archana Prasad; Sateesh Chandra Gupta; Abhishek Niranjan; Alok Lehri; Satya Shila Singh; Pratibha Misra; Debasis Chakrabarty
Solanum viarum Dunal, is an important medicinal plant widely used as a source of raw material for the steroidal drug industry. Out of various steroidal precursors, solasodine, an analogue of diosgenin is the most important source of raw material for the synthesis of steroidal drugs. In the present study, growth and phytochemical variations in different tissue (leaves, stem, roots, and berries) of two contrasting genotypes, prickled and prickleless Solanum viarum were evaluated under in vitro and field conditions. Significant variation in growth, yield and contents of glycoalkaloids, phenolics, and flavonoids were evident between two genotypes under in vitro and field conditions. Prickleless genotypes showed improved growth parameters both under in vitro and field conditions, that helps in contributing to higher yield over prickled plants. Tissue-specific chemical analysis revealed that the leaves and roots of prickleless plants serve as a better repertoire for bioactive phytomolecules. The vegetative parts of in vitro grown 50 days old prickleless plants showed comparable/higher metabolite content than 7–8 month old field-grown plants. Hence it can be used as an alternative production platform for further upscaling, elicitation, and precursor feeding targets that enhances its commercial utility. The expression analysis of seven genes involved in the regulation of important metabolite biosynthesis in both prickled and prickleless genotype of Solanum viarum was also examined. The diverse metabolite profiles are correlated with variations in gene expression profiles. This study provides information about the key metabolites and its biosynthetic pathway genes, which could be useful for the selection of an improved prickleless genotype (“Nishkantak”) of Solanum viarum. © 2021 Elsevier B.V.
N-(4-Butylphenyl)salicylaldimine at 160 K
(2003) S. Thamotharan; V. Parthasarathi; S.M. Anitha; Archana Prasad; T.R. Rao; Anthony Linden
In the title compound, C17H19NO, which is a Schiff base, an intramolecular O - H⋯N hydrogen bond involving the hydroxy group forms a six-membered ring with a graph-set motif of S(6). Several intermolecular C - H⋯π interactions occur between adjacent molecules which are arranged perpendicular to one another. © 2003 International Union of Crystallography Printed in Great Britain - all rights reserved.
Rice breeding for yield under drought has selected for longer flag leaves and lower stomatal density
(Oxford University Press, 2021) Santosh Kumar; Santosh Tripathi; Suresh Prasad Singh; Archana Prasad; Fahamida Akter; Md Abu Syed; Jyothi Badri; Sankar Prasad Das; Rudra Bhattarai; Mignon A Natividad; Marinell Quintana; Challa Venkateshwarlu; Anitha Raman; Shailesh Yadav; Shravan K Singh; Padmini Swain; A Anandan; Ram Baran Yadaw; Nimai P Mandal; S. B Verulkar; Arvind Kumar; Amelia Henry
Direct selection for yield under drought has resulted in the release of a number of drought-tolerant rice varieties across Asia. In this study, we characterized the physiological traits that have been affected by this strategy in breeding trials across sites in Bangladesh, India, and Nepal. Drought- breeding lines and drought-tolerant varieties showed consistently longer flag leaves and lower stomatal density than our drought-susceptible check variety, IR64. The influence of environmental parameters other than drought treatments on leaf traits was evidenced by close grouping of treatments within a site. Flag-leaf length and width appeared to be regulated by different environmental parameters. In separate trials in the Philippines, the same breeding lines studied in South Asia showed that canopy temperature under drought and harvest index across treatments were most correlated with grain yield. Both atmospheric and soil stress strengthened the relationships between leaf traits and yield. The stable expression of leaf traits among genotypes and the identification of the environmental conditions in which they contribute to yield, as well as the observation that some breeding lines showed longer time to flowering and higher canopy temperature than IR64, suggest that selection for additional physiological traits may result in further improvements of this breeding pool. © 2021 The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Synthesis and spectral studies on 3d metal complexes of mesogenic schiff base ligands. Part 1. Complexes of N-(4-butylphenyl) salicylaldimine
(2005) T.R. Rao; Archana Prasad
A novel mesogenic Schiff base, N-(4-butylphenyl) salicylaldimine (Hbpsal), was prepared and its ligational behavior towards some 3d metal ions studied. All the metal complexes synthesized were of the general formula, [M(bpsal) 2(H2O)2] where M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The complexes were structurally characterized by elemental analyses, molar conductance, IR, NMR, and electronic spectral data. The metallo mesogenic phases of the Cu(II) complex were studied by optical microscope. The spectral data show that Hbpsal acts as a bidentate ligand towards the metal ions. Mesogenic studies indicate that the ligand shows a focalconic structure with smectic-A phase while the Cu(II) complex displays smectic-A as well as smectic-E phases. Copyright © 2005 Taylor & Francis, Inc.
Synthesis and structural studies of some lanthanide complexes of salicylaldehyde anthranoyl hydrazone
(2002) T.R. Rao; Sabita Shrestha; Archana Prasad; K.K. Narang
Lanthanide complexes of the types Ln(sah)(OAc)·xH2O and Ln′(Hsah)2(X)·xH2O [Ln=Y, La, Nd, Gd, Tb and Dy; Ln′=Pr and Sm, X=NO3 and Cl; H2sah=salicylaldehyde anthranoyl hydrazone were synthesized and characterized by various physico-chemical techniques. The complexes are coloured and highly soluble in methanol, DMSO and DMF. Dehydration studies indicate the presence of both lattice-held and coordinated water molecules. IR, electronic and 1H NMR spectra have been recorded to establish the bonding sites of the ligand. Solution-state conductance measurements indicate the non-electrolytic nature of all of the complexes while solid-state electrical conductivity studies show Nd(sah)(OAc)·4H2O to be a semiconductor. Optical band gap measurements show the Pr, Sm and Dy complexes are direct band gap materials. X-ray diffraction patterns of selected complexes indicate orthorhombic structures.
Synthesis, spectral and electrochemical studies of Co(II) and Zn(II) complexes of a novel schiff base derived from pyridoxal
(2009) Archana Prasad; Ch. Parameswara Rao; Swati Mohan; Angad Kumar Singh; Rajiv Prakash; T.R. Rao
A novel Schiff-base, N - (4-n-butyl)phenylpyridoxaldimine (Hbppyr), was prepared and structurally characterized on the basis of elemental analyses, and mass, NMR IR spectral data. Hbppyr was found to coordinate through the azomethine nitrogen and phenolate oxygen in [M(bppyr)2(H2O)2].nH2O where M = Co and Zn; non-coordination through pyridine nitrogen was implied by the IR spectral data as well as by the cyclic voltammograms of Hbppyr in its free and complexed forms. Pyridoxal-derived ligands have been continuously attracting the attention of number of scientists, mainly for the evolution of iron chelators for the treatment of iron overload disease and cancer.[1-6] Recently, some important review articles appeared on specifically pyridoxal isonicotinoyl hydrazone (PIH) and its analogs in relation to its potential orally effective iron-chelating ability for the treatment of iron overload disease.[1,2] As a part of our systematic investigation[7, 8] on 3d and 4f metal complexes of some novel Schiff base ligands, we report here the synthetic and spectral studies on Co(II) and Zn(II) complexes of pyridoxal-drived Schiff base, (4-n-butyl)phenylpyridoxaldimine (Hbppyr), 1.[image omitted].LLC.
Updates on steroidal alkaloids and glycoalkaloids in Solanum spp.: Biosynthesis, in vitro production and pharmacological values
(Elsevier B.V., 2021) Preeti Patel; Archana Prasad; Kartikeya Srivastava; Satya Shila Singh; Debasis Chakrabarty; Pratibha Misra
Solanum is one of the largest genera of the family Solanaceae comprising > 2000 species distributed mostly in the tropical and subtropical regions of Australia, Africa, and some parts of Asia, such as China, India, and Japan. The nutraceutical and pharmaceutical values of the Solanum species are due to the presence of bioactive phyto-constituents such as steroidal saponins, steroidal alkaloids, terpenes, flavonoids, lignans, sterols, phenolic compounds, coumarins, etc. Among them, the presence of steroidal alkaloids and glycoalkaloids serves as major chemical markers of this genus. Steroidal alkaloids and glycoalkaloids have a special status in traditional and modern systems of medicine possessing a wide range of bioactivities, viz., antimicrobial, analgesic, hepatoprotective, immunomodulatory, anticancer, neurogenetic, etc. Steroidal alkaloids (STAs) are the major class of secondary metabolites found not only in plants but also in higher animals as well as in some aquatic invertebrates. They have a steroidal (cyclopentanophenanthrene) backbone skeleton with a nitrogen atom. The biosynthesis of these alkaloids takes place from steroids or triterpenoid pathway, on the basis of which they are further divided into different classes and subclasses. The present review is focused on the occurrence and biosynthesis of steroidal alkaloids in Solanaceae family. These compounds are mainly triterpene-derived molecules that are involved in various defense responses participating also in formulations of a wide range of phyto-pharmaceuticals. The addition of sugar moieties to the base skeleton by glycosyltransferases resulted in the formation of steroidal glycoalkaloids (STGAs), possessing a wide range of pharmacological values. The accumulation of these bioactive metabolites has been shown to be highly influenced by environmental and geographical factors. Hence, their production via tissue culture always offers an attractive alternate production platform. The current trends and biotechnological tools recently developed for the sustainable production and up-scaling of these bioactive constituents are focused in the present review. © 2021 Elsevier B.V.