Showing papers by "Department of Biotechnology published in 2004"
TL;DR: This review focuses on the ability and strategies of higher plants to respond and adapt to drought stress, including proline and glycine-betaine, as well as the role of abscisic acid under drought stress conditions.
2,015 citations
TL;DR: As angiogenesis is a major event in cancer growth and proliferation, tyrosine kinase inhibitors as a target for anti-angiogenesis can be aptly applied as a new mode of cancer therapy.
Abstract: Tyrosine kinases are important mediators of the signaling cascade, determining key roles in diverse biological processes like growth, differentiation, metabolism and apoptosis in response to external and internal stimuli. Recent advances have implicated the role of tyrosine kinases in the pathophysiology of cancer. Though their activity is tightly regulated in normal cells, they may acquire transforming functions due to mutation(s), overexpression and autocrine paracrine stimulation, leading to malignancy. Constitutive oncogenic activation in cancer cells can be blocked by selective tyrosine kinase inhibitors and thus considered as a promising approach for innovative genome based therapeutics. The modes of oncogenic activation and the different approaches for tyrosine kinase inhibition, like small molecule inhibitors, monoclonal antibodies, heat shock proteins, immunoconjugates, antisense and peptide drugs are reviewed in light of the important molecules. As angiogenesis is a major event in cancer growth and proliferation, tyrosine kinase inhibitors as a target for anti-angiogenesis can be aptly applied as a new mode of cancer therapy. The review concludes with a discussion on the application of modern techniques and knowledge of the kinome as means to gear up the tyrosine kinase drug discovery process.
446 citations
TL;DR: Of the various organisms reported, phytase production by Aspergillus sp.
251 citations
TL;DR: It is demonstrated that miltefosine induces apoptosis-like death in L. donovani based on observed phenomena such as nuclear DNA condensation, DNA fragmentation with accompanying ladder formation, and in situ labeling of DNA fragments by the terminal deoxyribonucleotidyltransferase-mediated dUTP-biotin nick end labeling method.
Abstract: Miltefosine causes leishmanial death, but the possible mechanism(s) of action is not known. The mode of action of miltefosine was investigated in vitro in Leishmania donovani promastigotes as well as in extra- and intracellular amastigotes. Here, we demonstrate that miltefosine induces apoptosis-like death in L. donovani based on observed phenomena such as nuclear DNA condensation, DNA fragmentation with accompanying ladder formation, and in situ labeling of DNA fragments by the terminal deoxyribonucleotidyltransferase-mediated dUTP-biotin nick end labeling method. Understanding of miltefosine-mediated death will facilitate the design of new therapeutic strategies against Leishmania parasites.
230 citations
TL;DR: The aspects discussed include: the mode of action; the structure and structure-function relationships; the structural modifications for improving functionality; recombinant streptokinase; microbial production; and recovery of this protein from crude broths.
207 citations
TL;DR: The study emphasizes the need for using a combination of different marker systems for a comprehensive genetic analysis of Basmati rice germplasm, and the high-level polymorphism generated by SSR, ISSR and AFLP assays described in this study shall provide novel markers to differentiate between traditional BasMati rice supplies from cheaper cross-bred Bas mati and long-grain non-Basmati varieties at commercial level.
Abstract: Molecular markers provide novel tools to differentiate between the various grades of Basmati rice, maintain fair-trade practices and to determine its relationship with other rice groups in Oryza sativa. We have evaluated the genetic diversity and patterns of relationships among the 18 rice genotypes representative of the traditional Basmati, cross-bred Basmati and non-Basmati (indica and japonica) rice varieties using AFLP, ISSR and SSR markers. All the three marker systems generated higher levels of polymorphism and could distinguish between all the 18 rice cultivars. The minimum number of assay-units per system needed to distinguish between all the cultivars was one for AFLP, two for ISSR and five for SSR. A total of 171 (110 polymorphic), 240 (188 polymorphic) and 160 (159 polymorphic) bands were detected using five primer combinations of AFLP, 25 UBC ISSR primers and 30 well distributed, mapped SSR markers, respectively. The salient features of AFLP, ISSR and SSR marker data analyzed using clustering algorithms, principal component analysis, Mantel test and AMOVA analysis are as given below: (i) the two traditional Basmati rice varieties were genetically distinct from indica and japonica rice varieties and invariably formed a separate cluster, (ii) the six Basmati varieties developed from various indica × Basmati rice crosses and backcrosses were grouped variably depending upon the marker system employed; CSR30 and Super being more closer to traditional Basmati followed by HKR228, Kasturi, Pusa Basmati 1 and Sabarmati, (iii) AFLP, ISSR and SSR marker data-sets showed moderate levels of positive correlation (Mantel test, r = 0.42–0.50), and (iv) the partitioning of the variance among and within rice groups (traditional Basmati, cross-bred Basmati, indica and japonica) using AMOVA showed greater variation among than within groups using SSR data-set, while reverse was true for both ISSR and AFLP data-sets. The study emphasizes the need for using a combination of different marker systems for a comprehensive genetic analysis of Basmati rice germplasm. The high-level polymorphism generated by SSR, ISSR and AFLP assays described in this study shall provide novel markers to differentiate between traditional Basmati rice supplies from cheaper cross-bred Basmati and long-grain non-Basmati varieties at commercial level.
122 citations
TL;DR: Knowledge of physiological and genetic characteristics, biochemical capabilities, and ecology of the relevant microbial species and consortia is an essential prerequisite for successful cleaning up of dye-contaminated water bodies, irrespective of the nature of the dye or the choice of biological treatment system being used.
Abstract: Publisher Summary This chapter reviews various dye decolorization methods and developments in biological treatment methods for dye. Biological methods are currently viewed as effective, specific, less energy intensive, and environmentally benign, because they result in partial or complete bioconversion of organic pollutants to stable nontoxic end products. Both biosorption and biodegradation have been explored as methods of biological treatments of dye-contaminated effluents. A wide variety of micro-organisms—including bacteria, fungi, and algae are capable of decolorizing a diverse range of dyes. Many bacteria are able to degrade dyes both aerobically and anaerobically. Biodegradation of azo dyes by bacteria is often initiated by azoreductase-driven cleavage of azo bonds, followed by aerobic or anaerobic degradation of resulting amines. On the other hand, fungal degradation typically originates from the lignolytic activity to degrade azo dyes aerobically with the aid of lignin peroxidase. Furthermore, knowledge of physiological and genetic characteristics, biochemical capabilities, and ecology of the relevant microbial species and consortia is an essential prerequisite for successful cleaning up of dye-contaminated water bodies, irrespective of the nature of the dye or the choice of biological treatment system being used.
122 citations
TL;DR: P. putida was found to be the most suitable biocatalyst for further studies as it showed higher reaction rate, lower K m, better growth rate, good yield and ee values and higher stability compared to the other two microorganisms.
Abstract: Several new microorganisms have been isolated with high nitrilase activity against ( RS )-mandelonitrile using the enrichment culture technique. The organisms were cultivated in liquid culture and the enzyme activity was determined at different phases of growth. The organisms having high enzyme titre were further grown and used as catalysts for the transformation of mandelonitrile to mandelic acid. The percentage conversion was checked with RP-HPLC and the enantiomeric excess was determined on a chiral column. Three isolates gave the desired product, ( R )-(−)-mandelic acid with high ee (%) and were identified as Pseudomonas putida , Microbacterium paraoxydans and Microbacterium liquefaciens . All three isolates showed good specific activity (0.33–0.50 U/mg min) with high ee (>93%) and E values. The conversion of racemic mandelonitrile to mandelic acid by these isolates was compared: P. putida was found to be the most suitable biocatalyst for further studies as it showed higher reaction rate ( k Rxn ), lower K m , better growth rate ( μ ), good yield and ee values and higher stability compared to the other two microorganisms.
87 citations
TL;DR: Both Zn and Cr seem to have a positive effect on insulin signaling leading to glucose uptake, and both Cr and Zn were found to have insulin mimetic activity.
Abstract: Patients on total parenteral nutrition without Cr supplementation develop symptoms similar to those of diabetes. Zn has been implicated in diabetes because of its antioxidant properties and interaction with insulin. To study the effect of these metal ions on insulin signaling proteins, cultured mouse skeletal muscle cells was used as an in vitro model, as the tissue accounts for more than 80% of insulin-stimulated glucose disposal in the body. In the present study, it has been observed that both Cr and Zn, upon prolonged exposure, could stimulate tyrosine phosphorylation of insulin receptor (IR) even in the absence of insulin. Insulin-mediated IR tyrosine phosphorylation was enhanced by the treatment with both of the metal ions. Both Cr and Zn could phosphorylate insulin receptor substrate-1 (IRS-1). Phosphorylation of IRS-1 induced by metal ions was higher than that induced by insulin. Hence, both Cr and Zn were found to have insulin mimetic activity. Both of the metal ions were also found to potentiate insulin-mediated activation of IRS-1. The basal level of glucose uptake was also increased by prolonged treatment of the cells with the metal ions. The ions could also enhance the insulin-stimulated glucose uptake into the cells. Therefore, both Zn and Cr seem to have a positive effect on insulin signaling leading to glucose uptake.
65 citations
TL;DR: A procedure for optimum secondary embryogenesis and maturation of Morus alba somatic embryos is described and the embryogenic competence was maintained for more than a year by repeated subculture.
52 citations
TL;DR: Data demonstrate a direct involvement of PPAR‐γ in insulin sensitization of TZD action on skeletal muscle cells, and suggest that pharmacological overexpression of muscle PPar‐γ gene in skeletal muscle might be a useful strategy for the treatment of insulin resistance.
Abstract: Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) expression is very low in skeletal muscle cells, which is one of the most important target tissues for insulin and plays a predominant role in glucose homeostasis. It has recently been shown that muscle-specific PPAR-gamma deletion in mouse causes insulin resistance. However, it is likely that the observed effects might be due to secondary interaction in whole animal. The aim of the study was to explore the role of muscle PPAR-gamma in insulin sensitivity. We stably transfected C2C12 skeletal muscle cells with plasmids containing sense or antisense constructs of PPAR-gamma and examined the effect of modulation of PPAR-gamma expression in terms of glucose uptake. Effect was also examined in insulin-resistant C2C12 skeletal muscle cells. In transfected C2C12 cell line, the inhibition of PPAR-gamma expression (23.0 +/-0.005%) was observed to induce insulin resistance as determined by functional assessment of 2-deoxyglucose incorporation. Overexpression of PPAR-gamma (28.5 +/- 0.008%) produced an additional effect on insulin (100 nM) and Pioglitazone (50 microM), resulting in 42.7 +/- 3.5% increase in glucose uptake as against 29.2+/-2.8% in wild-type C2C12 skeletal muscle cells differentiated under normal (2% horse serum) condition. Under similar treatment, PPAR-gamma overexpressing cells resistant to insulin exhibited enhanced glucose uptake upto 60.7 +/- 4.08%, as compared to 23.8 +/- 5.1% observed in wild-type C2C12 skeletal muscle cells. These data demonstrate a direct involvement of PPAR-gamma in insulin sensitization of TZD action on skeletal muscle cells, and suggest that pharmacological overexpression of muscle PPAR-gamma gene in skeletal muscle might be a useful strategy for the treatment of insulin resistance.
TL;DR: In this paper, the ability of Pleurotus spp., P. sajor-caju; P. platypus and P. citrinopileatus to treat pulp and paper mill effluent on a laboratory and pilot scale were studied.
Abstract: In this work, the ability of Pleurotus spp.:P. sajor-caju; P. platypus and P. citrinopileatus to treat pulp and paper mill effluent on a laboratory and pilot scale were studied. On the laboratory scale treatment, P. sajor-caju decolorized the effluent by 66.7% on day 6 of incubation. Inorganic chloride liberated by P. sajor-caju was 230.9% (814.0 mg/dl) and the COD was reduced by 61.3% (1302.0 mg/dl) on day 10 of treatment. In the pilot scale treatment maximum decolorization was obtained by P. sajor-caju (60.1%) on day 6 of the incubation. Inorganic chloride content was increased by 524.0 mg/dl (113.0%) and the COD was reduced by 1442.0 mg/dl (57.2%) by P. sajor-caju on day 7 of incubation. These results revealed that the treatment of pulp and paper mill effluent by P. sajor-caju proved as better candidate for the purpose than P. platypus and P. citrinopileatus.
TL;DR: RNAi technology is a potentially useful method to develop highly specific dsRNA-based gene-silencing therapeutics to treat viral infections, cancers, and inherited genetic disorders.
Abstract: One of the most exciting findings in recent years has been the discovery of RNA interference (RNAi). RNAi methodologies hold the promise to selectively inhibit gene expression in mammals. RNAi is an innate cellular process activated when a double-stranded RNA (dsRNA) molecule of greater than 19 duplex nucleotides enters the cell, causing the degradation of not only the invading dsRNA molecule, but also single-stranded (ssRNAs) RNAs of identical sequences, including endogenous mRNAs. The use of RNAi for genetic-based therapies has been widely studied, especially in viral infections, cancers, and inherited genetic disorders. As such, RNAi technology is a potentially useful method to develop highly specific dsRNA-based gene-silencing therapeutics.
TL;DR: Results indicate that 4-methane sulfonyl aroyl group at 5-position and other substituents of different quadrants of Craig plot on the phenyl moiety at the third position could lead to more potent candidates.
TL;DR: The growth and production pattern of phytase by a filamentous fungus, Aspergillus niger van Teighem, were studied in submerged culture at varying agitation rates and controlled and uncontrolled pH conditions to determine the volumetric oxygen transfer coefficient.
Abstract: The growth and production pattern of phytase by a filamentous fungus, Aspergillus niger van Teighem, were studied in submerged culture at varying agitation rates and controlled and uncontrolled pH conditions. Allowing the initial culture to grow under neutral condition with subsequent decline in pH resulted in increased phytase productivity. A maximum of 141 nkat/mL phytase was obtained when the broth pH was maintained at pH 2.5 as compared to 17 nkat/mL units at controlled pH 5.5. The culture morphology and rheological properties of the fermentation broth significantly varied with the agitation rate. The volumetric oxygen transfer coefficient was determined at different phases of fungal growth during batch fermentation using static gassing out and dynamic gassing out methods. The oxygen transfer coefficient (k(L)a) of the fermenter was found to be 125 h(-)(1) at 500 rpm as compared to 38 h(-)(1) at 200 rpm. The oxygen transfer rates at different phases of growth were significantly affected by cell mass concentration and fungal morphology. During the course of fermentation there was a gradual decline of k(L)a from 97 h(-)(1) on day 2 to 63 h(-)(1) on day 6 of fermentation, after which no significant change was observed. The degree of agitation considerably influenced the culture morphology where shear thinning of filamentous fungus was observed with the increase in agitation.
TL;DR: A new class of anti-inflammatory agents designed and synthesized for the first time wherein the utility of aliphatic oxime esters in modulating the anti- inflammatory activity profile is apparent is apparent.
TL;DR: It is shown that azadirachtin was less effective against third instar H. armigera larvae in inducing acute toxicity via topical treatment in comparison with rocaglamide, which could be due to the induced cytotoxicity at non‐specific cellular levels.
Abstract: Rocaglamide, a highly substituted benzofuran, was isolated and identified as the main biologically active component in Aglaia elaeagnoidea (syn. A. roxburghiana) for gram pod borer Helicoverpa armigera (Hubner). Addition of rocaglamide to an artificial diet retarded the growth of neonate larvae in a dose-dependent manner with EC 50 values of 0.76 p.p.m. These values compared favourably with azadirachtin (EC 50 = 0.23 p.p.m.). However, azadirachtin was apparently more potent than rocaglamide in inducing growth inhibition via oral administration to these first stadium larvae. The candidate compound was found to have LD 50 and LD 95 values of 0.40 and 1.02 μg per larva, respectively, in topical application against third instar larvae 96 h post-treatment. However, these values for azadirachtin were 8.16 and 25.8 μg per larva for the same period. This shows that azadirachtin was less effective against third instar H. armigera larvae in inducing acute toxicity via topical treatment in comparison with rocaglamide. However, severe morphological larval deformities were observed in such azadirachtin-treated larvae during the process of ecdysis. The cytotoxic nature of rocaglamide was established by evaluating dietary utilization and the results did not implicate any antifeedant effect but the toxicity-mediated effect due to reduced efficiency of conversion of ingested food. It was obvious that feeding deterrence is not the primary mode of action but a centrally mediated effect, which could be due to the induced cytotoxicity at non-specific cellular levels.
TL;DR: In vitro propagation techniques through rhizome cultures provide an efficient and rapid method for shoot propagation of S. parviflora and the levels of hyoscyamine and scopolamine were higher in in vitro-propagated plants than in the native growing plants.
Abstract: A rapid micropropagation system for Scopolia parviflora Nakai (Solanaceae), a rare medicinal plant native to Korea, was established using rhizome cultures. Shoots that originated from adventitious shoots of the rhizome were multiplied when the rhizomes were cultured on half-strength B5 liquid medium supplemented with various growth regulators. Optimum shoot multiplication was observed in half-strength B5 medium containing 3% (w/v) sucrose and 5.77 μM gibberellic acid (GA3). Each rhizome gave rise to an average of 12 shoots. Shoot elongation and root induction from multiple shoots occurred on growth regulator-free half-strength B5 solid medium. Healthy plantlets were transferred to a peat moss:vermiculite mixture for acclimatization, which was successful. The concentrations of tropane alkaloids, hyoscyamine and scopolamine were determined in different tissues of native growing plants, in vitro-propagated plants and acclimatized plants by high-performance liquid chromatography. The analysis revealed that the levels of hyoscyamine and scopolamine were higher in in vitro-propagated plants than in the native growing plants. When the rhizome was cut into segments and transferred to optimal culture conditions for multiple shoot propagation, only 12 weeks were required to produce a mature plant. We conclude that in vitro propagation techniques through rhizome cultures provide an efficient and rapid method for shoot propagation of S. parviflora.
TL;DR: The NaAsO 2 -induced cell death exhibited characteristics of apoptosis-like DNA laddering and fragmentation in both the affected wild type and resistant cells, however, poly(ADP-ribose)polymerase cleavage was evident in the wild type strain but not in the resistant strain.
TL;DR: The influence of various culture conditions on growth and ginkgolides (GKA and GKB), and bilobalide formation in callus and suspension cultures of Ginkgo biloba were investigated and callus induced from the leaf petioles exhibited distinct morphological and physiological responses.
Abstract: The influence of various culture conditions on growth and ginkgolides (GKA and GKB), and bilobalide formation in callus and suspension cultures ofGinkgo biloba were investigated. Callus induced from the leaf petioles exhibited distinct morphological and physiological responses. The cell biomass and ginkgolides content varied among the cell lines brownish callus lines produced high levels of ginkgolides and bilobalide in spite of poor cell growth. Among the culture media used, MS medium showed significant effect on cell growth and ginkgolides production. Low concentration of sucrose (3%) improved cell growth, while higher sucrose levels (5 and 7%) improved ginkgolides production. Cultivation of callus cultures above 28°C dramatically reduced their growth rate; however the cell lines grown at 36°C showed increased levels of bilobalide content. A 2.5-L balloon type bubble bioreactor (BTBB) was successfully developed for the cell growth and ginkgolides production.
Journal Article•
TL;DR: Skin barrier integrity and electrochemical stability of insulin was dependent on the charge applied during iontophoresis, and FT-IR spectroscopy and TGA studies showed that the skin hydration increased with increase in the charges applied and thus facilitated the transport of insulin.
Abstract: Transdermal iontophoresis is a physical enhancement strategy primarily for charged molecules and offers a number of advantages for the delivery of peptides and proteins. The singular advantage of iontophoresis lies in the precise control of dose by manipulating the current protocol. The objective of the present investigation was to understand the role of electronic parameters on iontophoretic transport of large peptides using insulin as a model peptide. Ex vivo permeation experiments were conducted using excised rat skin and the influence of varying current strengths, duration, on/off ratios and switching iontophoresis on insulin permeation were studied. High performance liquid chromatography (HPLC), polyacrylamide gel electrophoresis (SDS-PAGE) and thin layer chromatography (TLC) were used to assess the electrochemical stability of insulin; while Fourier transform infra-red (FT-IR) spectroscopy and thermogravimetric analysis (TGA) were used to understand the biophysical changes in skin during iontophoresis. The permeation of insulin was found to increase as a function of current strength and duration of current application. Skin barrier integrity and electrochemical stability of insulin was dependent on the charge applied during iontophoresis. FT-IR spectroscopy and TGA studies showed that the skin hydration increased with increase in the charge applied and thus facilitated the transport of insulin. Periodic iontophoresis did not show any significant difference in insulin permeation compared with continuous current application; 1:1 on/off ratio resulted in higher amount of insulin permeation, while flux was highest with mixed duty cycle. Switching iontophoresis was useful in reducing the pH shift and in improving the electrochemical stability of insulin at pH 3.6 and 7.4, respectively. The electroosmotic flow was influenced by the pH of the donor medium, as well as by the electrode polarity during switching and non-switching iontophoresis. Overall, the study demonstrates the issues related to the optimization of electronic parameters for the iontophoretic delivery of a large peptide.
TL;DR: Traditional fermentation systems employed by rural people of India were initially screened for phytate-hydrolysing microbes on solid medium supplemented with calciumphytate, and three new microbial genera are added to the list of phytase-producing organisms.
Abstract: Traditional fermentation systems employed by rural people of India were initially screened for phytate-hydrolysing microbes on solid medium supplemented with calcium phytate. It was followed by enzyme assay of culture filtrates to differentiate the phytase-producing microbes. Three new microbial genera are added to the list of phytase-producing organisms.
TL;DR: An efficient method was established for genetic transformation of Morus alba clone M5 using Agrobacterium tumefaciens mediated gene transfer using Cotyledon explants from in vitro grown seedlings and transgenic plants were micropropagated and successfully acclimatised.
TL;DR: Various experimental approaches adopted with RNAi and possible therapeutic applications are reviewed, which have the potential to facilitate the understanding of biological processes and potentially lead to exciting new drugs.
Abstract: RNA interference, part of a complicated network of interconnected pathways for cellular defence, RNA surveillance and development, has become a powerful tool for the experimental manipulation of gene expression. It is the process by which double-stranded (dsRNA) silences specific gene expression through homology-dependent degradation of cognate mRNA. The dsRNA is converted into 21nt small interfering RNAs (siRNAs), which directs a complex ribonuclease system to substrate mRNA targets. The degradation of the target mRNA is initiated with the cleavage at a position corresponding to the centre of the siRNA. Dissecting individual cellular pathways to reveal the function of numerous proteins is an approach to drug discovery. Interfering RNA (RNAi) serves as a rapid and convenient tool, which works in various organisms. RNAi technology has the potential to facilitate our understanding of biological processes and potentially lead to exciting new drugs. Here we review various experimental approaches adopted with RNAi and possible therapeutic applications.
TL;DR: Aqueous and organic solvent extracts tested by agar-well diffusion method against 12 human pathogenic bacteria and 3 fungal strains showed activity to most of the organisms.
Abstract: Isolation of the natural products from the stems of Jatropha maheshwarii yielded 5 compounds such as Friedelin (0.16%), epi-friedelinol (0.12%), n-octacosanol (0.11%), β-sitosterol (0.2%), and β-sitosterol-3-β-D-glucopyranoside (0.24%). Aqueous and organic solvent extracts tested by agar-well diffusion method against 12 human pathogenic bacteria and 3 fungal strains showed activity to most of the organisms. Methanol extract exhibited maximum activity. Activity against S. aureus provides scientific evidence for use in skin diseases and toothaches.
TL;DR: The ginkgolides and bilobalide contents were not correlated with the production between dominant trees and their corresponding cells, and NAA was better at callogenesis than 2,4-D in both the female and male trees.
Abstract: Ginkgolides (GK) and bilobalide are valuable compounds that belong to the lactone terpene. The contents of these metabolites were determined by HPLC from female and male tree ofGinkgo biloba L. The productivity ofG. biloba cells was also compared with the corresponding individual trees. High variations in the ginkgolides and bilobalide were observed from different individuals, plant parts, and cultured cells. The ginkgolides and bilobalide contents were different depending on the plant parts. Callus was obtained from various plant tissues, and NAA was better at callogenesis than 2,4-D in both the female and male trees. The plants and their corresponding cells showed considerable variation in their ginkgolides and bilobalide concentrations. The ginkgolides and bilobalide contents were not correlated with the production between dominant trees and their corresponding cells. Light irradiation enhanced the production of GK-A and GK-B, however, the concentration of bilobalide decreased under dark conditions.
Journal Article•
TL;DR: Solasodine contents in the regenerated shoots was found to be 10 times higher than the callus culture and approached towards the field grown plants, while thin layer chromatography revealed the presence of three compounds.
Abstract: Leaf and hypocotyl explants of 15 days old aseptically grown seedlings of Solanum laciniatum were cultured on MS medium supplemented with NAA (2 mg/l) and kinetin (0.5 mg/l) for callus initiation. For maintenance and proliferation of callus MS medium supplemented with 2,4-D (1 mg/l) and kinetin (0.5 mg/l) was used. The growth of the calli derived from hypocotyls increased with time of incubation and remained almost constant after 45 days. The solasodine content in callus culture was maximum after 30 days of incubation. Addition of L-arginine in the medium (50-150 mg/l) increased growth as well as chlorophyll content in the callus culture. The solasodine content also increased up to 1.2 to 1.4 times in these cultures. High frequency shoot regeneration was obtained in MS medium having BA (4 mg/l) and IBA (0.25 mg/l). For shoot multiplication, MS medium having BA (4 mg/l) was used. Shoots rooted on the same medium. Organogenesis promoted solasodine accumulation in the cultures. Regenerated shoots yielded higher solasodine content than undifferentiated as well as organogenic callus. Solasodine contents in the regenerated shoots was found to be 10 times higher than the callus culture and approached towards the field grown plants. Thin layer chromatography revealed the presence of three compounds. The most predominant spot (Rf 0.789) corresponded to the reference solasodine.
TL;DR: In this article, phytochemical analysis revealed the presence of flavones and triterpenes in all the solvent extracts, coumarins and steroids in hexane and chloroform extracts, quinine, alkaloids, lignins and phenols in chloro-form and methanol extracts and proteins, saponins, starch, sugar and tannin in methanoline extract.
Abstract: Leaves of Phyllanthus singampattiana, locally known as Aathuchadai by the Kanis of Tamil Nadu in India is consumed for curing jaundice, diarrhea and dysentery. Preliminary phytochemical analysis revealed the presence of flavones and triterpenes in all the solvent extracts, coumarins and steroids in hexane and chloroform extracts, quinine, alkaloids, lignins and phenols in chloroform and methanol extracts and proteins, saponins, starch, sugar and tannin in methanol extract. Isolation yielded friedelin, epi-friedelinol, n-octacosanol, α-amyrin, β-sitosterol, luteolin and β-sitosterol-3β-D-glucopyranoside. The aqueous and solvent extracts when tested against 11 gram-negative and 2 gram-positive bacteria and 3 fungi expressed activity to most of the organisms. Activity was not recorded for hexane extract, against A. niger and A. flavus (except methanol extract) and against S. aureus in lower concentration of chloroform extract. Methanol extract showed more activity amongst all the solvent extracts, particularly remarkable activity recorded against gram-positive bacteria. Activity against diarrhea and dysentery causing organisms such as A. hydrophila, E. aerogenes, K. pneumoniae, P. vulgaris, S. enteritidis, V. cholerae, V. parahaemolyticus and V. vulnificus substantiated the claims of the ethnic uses. Activity against C. albicans indicates the possibility to develop drugs for skin diseases.
TL;DR: The present study describes an improved methodology for the unambiguous determination and estimation of gibberellins from fermentation broth using HPLCMS/MS, which revealed the formation of reduced GA3 in the broth.
Abstract: A method for the detection of gibberellins produced by Fusarium verticilliodes is described using HPLCMS/MS (HPLC tandem MS). A Hypersil (5 μm) octadecylsilane column with methanol/water as eluent in the ratio 3:1 at a flow rate of 0.5 mllmin was used. In the HPLCMS, GA 3 (gibberellic acid; m/z 346.3) eluted at retention time t r = 3.08 min, with the corresponding mass chromatogram having peaks at mlz 346.7 and 328.8 corresponding to the M + and M + -H 2 O ions respectively. The ethyl acetate extract from the broth, subjected to HPLCMS analysis under similar conditions, showed a constituent with t, = 2.13 min, the mass chromatogram of which exhibited peaks at m/z 348.9 and 331.9 corresponding to the MH + and MH + -H 2 O ions respectively. Comparison of the MS and MS/MS results (direct infusion) of an authentic sample of GA 3 and the ethyl acetate extract from the broth revealed the formation of reduced GA 3 in the broth. The present study, utilizing HPLCMS/MS, describes an improved methodology for the unambiguous determination and estimation of gibberellins from fermentation broth.
TL;DR: The treatment of cells with p38 MAPK inhibitor, SB203580, blocked the insulin stimulated glucose uptake in sensitive as well as resistant cells and it also prevented the activation of p38 by insulin, suggesting the potential involvement of p 38 as well the mechanistic role of TZDs in insulin resistance.
Abstract: We have previously reported that thiazolidinediones (TZDs) are able to restore the tyrosine phosphorylation of insulin receptor and insulin receptor substrate-1, activation of phosphatidyl inositol 3-kinase and glucose uptake in insulin resistant skeletal muscle cells [21]. In this study, we investigated the effects of insulin stimulation and TZDs on the role of mitogen-activated protein kinase (MAPK) in insulin resistant skeletal muscle cells. All the three MAPKs [extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 MAPK] were activated by insulin in the sensitive skeletal muscle cells. In contrast, activation of p38 MAPK was impaired in insulin resistant cells, where as ERK and JNK were activated by insulin. Treatment with TZDs resulted in the restoration of p38 MAPK activity in insulin resistant cells. The treatment of cells with p38 MAPK inhibitor, SB203580, blocked the insulin stimulated glucose uptake in sensitive as well as resistant cells and it also prevented the activation of p38 by insulin. These results suggest the potential involvement of p38 as well as the mechanistic role of TZDs in insulin resistance.