Isolation, in vitro, and in vivo pathogenicity test of Tilapia lake virus (TiLV) and development of a prognostic semi-quantitative lesion scoring system for differentiating clinical/subclinical infection in farmed tilapia (Oreochromis niloticus L.)

Tilapia lake virus ('TiLV-MH-2022') was recently recovered from the naturally infected farmed tilapia. Reverse transcription-polymerase chain reaction (RT-PCR) using segment 1 specific primers, followed by Sanger sequencing, confirmed the infection. The pairwise sequence homology of segment 1 showed its close relationship with the previous isolates. The virus was successfully detected from the mucus, which emphasised the possibility of non-invasive screening of tilapia on a large scale. The virus inoculum prepared from the infected tissues was tested for in vivo and in vitro pathogenicity. Around 100-140 nm-sized electron-dense virus particles were observed in the infected OnlL cells. Based on the onset of symptoms and lesions, all RT-PCR-positive fish were categorised into two groups, 'clinical' and 'subclinical'. A lesion-scoring technique was developed for assessing the pathogenicity of the virus isolate. The external and internal gross lesions and histopathological alterations in the critical organs of the fish, such as the brain, kidney, gills, and liver, were assessed on a scale of 0 (no gross lesion) to 5 (most severe lesions). Overall lesion score was significantly high in the clinical and subclinical groups for gross and histopathology, respectively. This study is the first such attempt to standardise a semi-quantitative lesion scoring technique for TiLV infection, which establishes a clinical relevance and prognostic ability to distinguish between the apparent and inapparent infection.

Addition of oral Fexofenadine to topical therapy leads to a significantly greater reduction in the serum IL-31 levels in mild to moderate pediatric atopic dermatitis

BACKGROUND

Recent evidence has suggested that oral antihistamines could have a beneficial role in atopic dermatitis (AD) due to their anti-inflammatory action. Hence, we aimed to evaluate the effectiveness of adding an oral second generation, non-sedating, H1 antihistamine (Fexofenadine) to topical treatment in AD.

MATERIALS AND METHODS

In this prospective randomized study, a total of 50 patients with a diagnosis of mild to moderate atopic dermatitis were recruited and randomized into two groups A (appropriate topical treatment combined with oral fexofenadine) and B (appropriate topical treatment without oral fexofenadine). Both groups received the respective treatments for a duration of 8 weeks.

RESULTS

There was no significant difference between the two groups in terms of SCORAD and the 5-D Itch Score at any of the time points (2 weeks, 4 weeks, 8 weeks). However, the serum IL-31 (ng/ml) decreased significantly from baseline in the fexofenadine group after 8 weeks of treatment.

CONCLUSIONS

Although we could not conclusively confirm the clinical efficacy of adding oral fexofenadine to topical treatment in AD, serological evaluation indicates that fexofenadine treatment can lead to significant lowering of serum IL-31 levels in AD patients.

Bioactive phytocompound mulberroside C and endophytes of Morus alba as potential inhibitors of HIV-1 replication: a mechanistic evaluation

OBJECTIVES

Despite considerable advancement in antiretroviral therapy, development of safe, effective, and multi-targeted drugs for HIV still remains a big challenge. Endophytes are untouched and, hence, an important and novel sources in drug discovery endeavours. The present study was conducted to identify the anti-HIV compounds from Morus alba and endophytes isolated from it.

METHODS

The extracts of isolated endophytes were screened using high-performance liquid chromatography (HPLC). Further, all samples were analysed for their cytotoxicity using a thiazolyl blue tetrazolium bromide assay. Subsequently, anti-HIV activity was performed using cell-based and cell-free assay. At the end, potential endophytes were identified using gene sequencing.

RESULTS

A total of 27 endophytes were isolated from the eight stem bark samples of M. alba. Of the 27 endophytes, extracts of total of four endophytes showed a profile similar to the M. alba plant when analysed by HPLC. Further experimentation with extracts of these four endophytes, along with an extract of M. alba stem bark and its bioactive molecule, mulberroside C, revealed that all these six samples have good inhibitory potential for HIV. Among them, mulberroside C and two endophytic fungal extracts showed very potent anti-HIV activity. Subsequently, mechanistic studies at the molecular level showed that out of six test samples, three acted as protease inhibitors. Further, all four potential endophytes were identified using gene sequencing.

CONCLUSIONS

The overall findings of these studies can help in the development of a novel anti-HIV candidate from mulberroside C, an extract of stem bark of M. alba and extracts of these endophytes. However, further validation and clinical studies are required to develop an anti-HIV drug.

Inhibitory mechanism of an antifungal drug, caspofungin against amyloid β peptide aggregation: Repurposing via neuroinformatics and an experimental approach

The multifactorial neurological condition called Alzheimer's disease (AD) primarily affects elderly individuals. Despite the calamitous consequences of AD, curative strategies for a regimen to apply remain inadequate as several factors contribute to AD etiology. Drug repurposing is an advance strategy prior to drug discovery as various effective drugs perform through alteration of multiple targets, and the present "poly-pharmacology" can be a curative approach to complex disorders. AD's multifactorial behavior actively encourages the hypothesis for a drug design approach focused on drug repurposing. In this study, we discovered that an antifungal drug, Caspofungin (CAS) is a potent Aβ aggregation inhibitor that displays significantly reduced toxicity associated with AD. Drug reprofiling and REMD simulations demonstrated that CAS interacts with the β-sheet section, known as Aβ amyloid fibrils hotspot. CAS leads to destabilization of β-sheet and, conclusively, in its devaluation. Later, in vitro experiments were acquired in which the fibrillar volume was reduced for CAS-treated Aβ peptide. For the first time ever, this study has determined an antifungal agent as the Aβ amyloid aggregation's potent inhibitor. Several efficient sequence-reliant potent inhibitors can be developed in future against the amyloid aggregation for different amyloid peptide by the processing and conformational optimization of CAS.

Clinical evaluation of an in-house-developed real-time RT-PCR assay for serotyping of dengue virus

In the present study, an in-house-developed real-time RT-PCR (rRT-PCR) for serotyping of dengue virus (DENV) was evaluated for its performance, using 612 clinical samples. Compared to the composite reference standard, the in-house-developed rRT-PCR had an overall sensitivity of 97.5% and a specificity of 100%. The assay had a sensitivity of 100%, 95.6%. 96.9% and 100% for detecting DENV-1, DENV-2, DENV-3 and DENV-4, respectively. We recommend periodic evaluation of real-time RT-PCR assays for detecting DENV serotypes with a large number of samples and the use of at least two assays that target different regions of DENV genomes.

Bleomycin modulates amyloid aggregation in β-amyloid and hIAPP

Aberrant misfolding and amyloid aggregation, which result in amyloid fibrils, are frequent and critical pathological incidents in various neurodegenerative disorders. Multiple drugs or inhibitors have been investigated to avert amyloid aggregation in individual peptides, exhibiting sequence-dependent inhibition mechanisms. Establishing or inventing inhibitors capable of preventing amyloid aggregation in a wide variety of amyloid peptides is quite a daunting task. Bleomycin (BLM), a complex glycopeptide, has been widely used as an antibiotic and antitumor drug due to its ability to inhibit DNA metabolism, and as an antineoplastic, especially for solid tumors. In this study, we investigated the dual inhibitory effects of BLM on Aβ aggregation, associated with Alzheimer's disease and hIAPP, which is linked to type 2 diabetes, using both computational and experimental techniques. Combined results from drug repurposing and replica exchange molecular dynamics simulations demonstrate that BLM binds to the β-sheet region considered a hotspot for amyloid fibrils of Aβ and hIAPP. BLM was also found to be involved in β-sheet destabilization and, ultimately, in its reduction. Further, experimental validation through in vitro amyloid aggregation assays was obtained wherein the fibrillar load was decreased for the BLM-treated Aβ and hIAPP peptides in comparison to controls. For the first time, this study shows that BLM is a dual inhibitor of Aβ and hIAPP amyloid aggregation. In the future, the conformational optimization and processing of BLM may help develop various efficient sequence-dependent inhibitors against amyloid aggregation in various amyloid peptides.

Bleomycin acts as a dual inhibitor against both amyloid β and human islet amyloid polypeptide by binding to the β-sheet grooves considered as the amyloids hotspot.

Synergistic approaches unraveling regulation and aggregation of intrinsically disordered β-amyloids implicated in Alzheimer's disease

Alzheimer's disease is a severe brain illness that causes vast numbers of nerve cells in the brain to die, driven by the production and deposition of amyloid beta (Aβ) peptides. Intrinsically disordered proteins (IDPs) generally lack stable structures and are abundant in nature. Aβ peptide is a well-known IDP with a wide range of oligomeric forms. Dysfunctions in Aβ lead to oligomerization, formation of fibrils, and neurodegenerative disorders or other forms of dementia. In this study, we used replica exchange molecular dynamics (REMD) to elucidate the roles of different osmolytes, particularly urea and trimethylamine N-oxide (TMAO), to study shifts in IDP populations. REMD samples the conformational space efficiently and at physiologically relevant temperatures, compared to conventional molecular dynamics that sample at a constant temperature. Urea is known to minimize the aggregation process, while TMAO is beneficial for its stabilizing action. The two osmolytes displayed characteristic effects on Aβ peptides and resulted in progressive modulation of conformations. The present study underlines the hypothesis of "modulation of conformational ensembles" to explain the regulation and aggregation of IDPs.

Important amino acid residues of hexachlorocyclohexane dehydrochlorinases (LinA) for enantioselective transformation of hexachlorocyclohexane isomers

LinA-type1 and LinA-type2 are two well-characterized variants of the enzyme ‘hexachlorocyclohexane (HCH)-dehydrochlorinase’. They differ from each other at ten amino acid positions and exhibit differing enantioselectivity for the transformation of the (–) and (+) enantiomers of α-HCH. Amino acids responsible for this enantioselectivity, however, are not known. An in silico docking analysis identified four amino acids (K20, L96, A131, and T133) in LinA-type1 that could be involved in selective binding of the substrates. Experimental studies with constructed mutant enzymes revealed that a combined presence of three amino acid changes in LinA-type1, i.e. K20Q, L96C, and A131G, caused a reversal in its preference from the (–) to the (+) enantiomer of α-HCH. This preference was enhanced by the additional amino acid change T133 M. Presence of these four changes also caused the reversal of enantioselectivity of LinA-type1 for δ-HCH, and β-, γ-, and δ-pentachlorocyclohexens. Thus, the residues K20, L96, A131, and T133 in LinA-type1 and the residues Q20, C96, G131, and M133 in LinA-type 2 appear to be important determinants for the enantioselectivity of LinA enzymes.

Functional attributes of evolutionary conserved Arg45 of Wolbachia (Brugia malayi) translation initiation factor-1

AIM

Wolbachia is a promising antifilarial chemotherapeutic target. Translation initiation factor-1 (Tl IF-1) is an essential factor in prokaryotes. Functional characterization of Wolbachia's novel proteins/enzymes is necessary for the development of adulticidal drugs.

MATERIALS & METHODS

Mutant, Wol Tl IF-1 R45D was constructed by site directed mutagenesis. Fluorimetry and size exclusion chromatography were used to determine the biophysical characteristics. Mobility shift assay and fluorescence resonance energy transfer were used to investigate the functional aspect of Wol Tl IF-1 with its mutant.

RESULTS

Both wild and mutant were in monomeric native conformations. Wild exhibits nonspecific binding with ssRNA/ssDNA fragments under electrostatic conditions and showed annealing and displacement of RNA strands in comparison to mutant.

CONCLUSION

Point mutation impaired RNA chaperone activity of the mutant and its interaction with nucleotides.

Effects of gamma irradiation on chickpea seeds vis-a-vis total seed storage proteins, antioxidant activity and protein profiling

The present work describes radiation—induced effects on seed composition vis—à—vis total seed proteins, antioxidant levels and protein profiling employing two dimensional gel electrophoresis (2D—GE) in kabuli and desi chickpea varities. Seeds were exposed to the radiation doses of 1,2,3,4 and 5 kGy. The total protein concentrations decreased and antioxidant levels were increased with increasing dose compared to control seed samples. Radiation induced effects were dose dependent to these seed parameters while it showed tolerance to 1 kGy dose. Increase in the dose was complimented with increase in antioxidant levels, like 5 kGy enhanced % scavenging activities in all the seed extracts. Precisely, the investigations reflected that the dose range from 2 to 5 kGy was effective for total seed storage proteins, as depicted quantitatively and qualitative 2D—GE means enhance antioxidant activities in vitro.

DNA polymorphisms in chickpea accessions as revealed by PCR-based markers

Chickpea is a food legume which is alleged to be a preferred source of protein next only to milk. Germplasm of cultivated chickpea available is deficient in desired genetic variation. Genetic manipulations therefore, necessitate the genetic exploitation of its related annual and wild species. 42 RAPD and 41 ISSR markers were employed to ascertain polymorphism across 20 genotypes which were collected from 10 different geographical areas of the world. RAPD marker detected 51% genetic polymorphisms while ISSR marker detected 54 %. With an average of 6.5 each RAPD primer amplified 5—8 bands. Similarly with an average of 7.9 each ISSR primer amplified 4—12 bands. The cluster dendrogram demonstrated a similarity coefficient range from 0.80 to 0.92 due to RAPD markers, whereas with ISSR primers the cluster dendrogram showed similarity coefficient of 0.60 to 1.00. Accessions from same geographical area seem to be genetically similar than those from geographically distant and isolated ones. When however compared, interestingly the ISSR dendrogram showed more correlation with pedigree data than the RAPD dendrogram. The variability index worked out in the present study ranges from 0.79 to 0.96. Since the ultimate reason for such studies is selection of diverse genetic accessions for their recommendation to breeding programmers, the accessions like ICC6263, ICC6306 and ICC17160 can be recommended as parents. Further breeding programmes can therefore be planned to procure additional variation complexes in chickpea genetic stocks.

Purification and dose-dependent toxicity study of abrin in swiss albino male mice

Abrin, a phytotoxin obtained from the seeds of the Abrus precatorius plant, is highly toxic with an estimated human fatal dose of 0.1—1 μg/kg. In this study, abrin was purified and characterized through SDS PAGE and mass spectrometry analysis; further study on toxicity was carried out to investigate the alteration in biochemical, and hematological variables through histopathological observations in mice. The intraperitoneal LD50 value of purified abrin for mice was found to be 0.91μg/kg of body weight. Mice were exposed to 0.4 and 1.0 LD50 abrin doses intraperitoneally and observed on days 1, 3, and 7. Plasma GOT and GPT levels increased significantly at both doses. At 1.0 LD50 dose, alkaline phosphatase, bilirubin, urea, uric acid, and creatinine levels increased, whereas albumin, total protein, glucose and cholesterol levels decreased significantly. Abrin intoxication also altered the hemoglobin, WBC, and RBC counts significantly at 1.0 LD50 dose. Liver GSH levels decreased while lipid peroxidation increased significantly in a dose—dependent manner. Biochemical changes were supported by the histological investigation, which also showed the degenerative changes in organs. In conclusion, abrin intoxication caused toxic effects and severe damages on studied organs mediated through alteration in biochemical and hematological variables, lipid peroxidation, and degeneration.

Wolbachia transcription elongation factor "Wol GreA" interacts with α2ββ'σ subunits of RNA polymerase through its dimeric C-terminal domain

OBJECTIVES

Wolbachia, an endosymbiont of filarial nematode, is considered a promising target for therapy against lymphatic filariasis. Transcription elongation factor GreA is an essential factor that mediates transcriptional transition from abortive initiation to productive elongation by stimulating the escape of RNA polymerase (RNAP) from native prokaryotic promoters. Upon screening of 6257 essential bacterial genes, 57 were suggested as potential future drug targets, and GreA is among these. The current study emphasized the characterization of Wol GreA with its domains.

METHODOLOGY/PRINCIPAL FINDINGS

Biophysical characterization of Wol GreA with its N-terminal domain (NTD) and C-terminal domain (CTD) was performed with fluorimetry, size exclusion chromatography, and chemical cross-linking. Filter trap and far western blotting were used to determine the domain responsible for the interaction with α2ββ'σ subunits of RNAP. Protein-protein docking studies were done to explore residual interaction of RNAP with Wol GreA. The factor and its domains were found to be biochemically active. Size exclusion and chemical cross-linking studies revealed that Wol GreA and CTD exist in a dimeric conformation while NTD subsists in monomeric conformation. Asp120, Val121, Ser122, Lys123, and Ser134 are the residues of CTD through which monomers of Wol GreA interact and shape into a dimeric conformation. Filter trap, far western blotting, and protein-protein docking studies revealed that dimeric CTD of Wol GreA through Lys82, Ser98, Asp104, Ser105, Glu106, Tyr109, Glu116, Asp120, Val121, Ser122, Ser127, Ser129, Lys140, Glu143, Val147, Ser151, Glu153, and Phe163 residues exclusively participates in binding with α2ββ'σ subunits of polymerase.

CONCLUSIONS/SIGNIFICANCE

To the best of our knowledge, this research is the first documentation of the residual mode of action in wolbachial mutualist. Therefore, findings may be crucial to understanding the transcription mechanism of this α-proteobacteria and in deciphering the role of Wol GreA in filarial development.

Immunization with a multisubunit vaccine considerably reduces establishment of infective larvae in a rodent model of Brugia malayi

Although recombinant vaccines have several advantages over conventional vaccines, protection induced by single antigen vaccines is often inadequate for a multicellular helminth parasite. Therefore, immunoprophylactic efficacy of cocktail antigen vaccines comprised of several combinations of three Brugia malayi recombinant proteins BmAF-Myo, Bm-iPGM and Bm-TPP were evaluated. Myosin+TPP and iPGM+TPP provided the best protection upon B. malayi infective larval challenge with ∼70% reduction in adult worm establishment over non-vaccinated animals that was significantly higher than the protection achieved by any single antigen vaccine. Myosin+iPGM, in contrast did not provide any enhance protection over the single recombinant protein vaccines. Specific IgG, IgM level, IgG antibody subclasses levels (IgG1, IgG2a, IgG2b, IgG3), lymphocyte proliferation, reactive oxygen species level and cytokines level were also determined to elucidate the characteristics of the protective immune responses. Thus the study undertaken provided more insight into the cocktail vaccination approach to combat LF.

Inhibition of P. falciparum PFATP6 by curcumin and its derivatives: a bioinformatic study

Curcumin, a yellow spice has been shown to have many pathological uses including cancer and malaria. Recent experimental data have shown the inhibitory effect of curcumin and its two derivatives on the growth of Plasmodium falciparum in cell culture at low micromolar concentrations. Previous studies have suggested that Ca(2+)—ATPase (PfATP6) of P. falciparum is the target of many antimalarial drugs. However, the mechanism of inhibition of Ca(2+)—ATPase (PfATP6) is not known. In addition, it is not clear which specific isomeric form of curcumin is the most potent inhibitor of P. falciparum. Here we address this issue using bioinformatics tools. We generated a molecular model of Ca(2+)—ATPase (PfATP6) of P. falciparum and carried out molecular docking of all curcumin analogues of Zinc database of compounds (zinc.docking.org). Two molecular docking programs Glide and FlexX were used to determine binding feasibility of 351 analogues of curcumin. The comparison of docking parameters showed, more than 20 analogues are better ligands of PfATP6 than curcumin itself. . The binding of curcumin and its analogues to PFATP6 is mediated by both hydrophobic and polar interactions. Our results suggest that curcumin analogues are promising lead compounds for the development of antimalarial drugs.

Molecular characterization of NAD+-dependent DNA ligase from Wolbachia endosymbiont of lymphatic filarial parasite Brugia malayi

The lymphatic filarial parasite, Brugia malayi contains Wolbachia endobacteria that are essential for development, viability and fertility of the parasite. Therefore, wolbachial proteins have been currently seen as the potential antifilarial drug targets. NAD(+)-dependent DNA ligase is characterized as a promising drug target in several organisms due to its crucial, indispensable role in DNA replication, recombination and DNA repair. We report here the cloning, expression and purification of NAD(+)-dependent DNA ligase of Wolbachia endosymbiont of B. malayi (wBm-LigA) for its molecular characterization. wBm-LigA has all the domains that are present in nearly all the eubacterial NAD(+)-dependent DNA ligases such as N-terminal adenylation domain, OB fold, helix-hairpin-helix (HhH) and BRCT domain except zinc-binding tetracysteine domain. The purified recombinant protein (683-amino acid) was found to be biochemically active and was present in its native form as revealed by the circular dichroism and fluorescence spectra. The purified recombinant enzyme was able to catalyze intramolecular strand joining on a nicked DNA as well as intermolecular joining of the cohesive ends of BstEII restricted lamda DNA in an in vitro assay. The enzyme was localized in the various life-stages of B. malayi parasites by immunoblotting and high enzyme expression was observed in Wolbachia within B. malayi microfilariae and female adult parasites along the hypodermal chords and in the gravid portion as evident by the confocal microscopy. Ours is the first report on this enzyme of Wolbachia and these findings would assist in validating the antifilarial drug target potential of wBm-LigA in future studies.

Insights into the internalization and retrograde trafficking of Dengue 2 virus in BHK-21 cells

Background

Dengue virus (DENV) enters cells via endocytosis, traffics to perinuclear (PN) region, the site of morphogenesis and exits by exocytosis. This study aims to understand the role of dynamin II, endosomes, microtubules (MT) and dynein in the early events of DENV replication.

Findings

Using double immunoflourescence labelling of DENV-2 infected BHK-21 cells it was observed that the surface envelope (E) protein of the virion associated with dynamin II from 0–30 min post infection (p.i.). The sphincter like array of dynamin II supported its pinchase-like activity. The association with endosomes was observed from 0 min at cell periphery to 30 min in the perinuclear (PN) region, suggesting that internalization continued for 30 min. Association of E protein with alpha-tubulin was observed from 8 h indicating that it was the newly translated protein that trafficked on the MT. Dynein was found to associate with the E protein from 4 h in the cytoplasm to 48 h in the PN region and dissociate at 72 h. Association of E protein with dynein was confirmed by immunoprecipitation. Overexpression of dynamitin, which disrupts the dynein complex, resulted in loss of trafficking of viral E and core proteins. The findings corroborated with the growth kinetics assessed by quantitation of viral RNA in infected BHK-21 cells. The detection of E protein at 4 h–8 h correlated with detectable increase in viral RNA from 8 h. The detection of high concentrations of E protein in the PN region at 24–48 h coincided with release of virus into the supernatant starting from 36 h p.i. The dissociation of dynein from E protein by 72 h was coincident with maximum release of virus, hinting at a possible negative feedback for viral protein translation.

Conclusion

The study shows for the first time the association of dynamin II with DENV-2 during entry and dynein dependent retrograde trafficking of DENV proteins on microtubules.

Maternal footprints of Southeast Asians in North India

We have analyzed 7,137 samples from 125 different caste, tribal and religious groups of India and 99 samples from three populations of Nepal for the length variation in the COII/tRNA(Lys) region of mtDNA. Samples showing length variation were subjected to detailed phylogenetic analysis based on HVS-I and informative coding region sequence variation. The overall frequencies of the 9-bp deletion and insertion variants in South Asia were 1.9 and 0.6%, respectively. We have also defined a novel deep-rooting haplogroup M43 and identified the rare haplogroup H14 in Indian populations carrying the 9-bp deletion by complete mtDNA sequencing. Moreover, we redefined haplogroup M6 and dissected it into two well-defined subclades. The presence of haplogroups F1 and B5a in Uttar Pradesh suggests minor maternal contribution from Southeast Asia to Northern India. The occurrence of haplogroup F1 in the Nepalese sample implies that Nepal might have served as a bridge for the flow of eastern lineages to India. The presence of R6 in the Nepalese, on the other hand, suggests that the gene flow between India and Nepal has been reciprocal.

Analysis of the PB2 gene reveals that Indian H5N1 influenza virus belongs to a mixed-migratory bird sub-lineage possessing the amino acid lysine at position 627 of the PB2 protein

Outbreaks of highly pathogenic avian influenza (HPAI) H5N1 virus were reported for the first time in India during February 2006. Herein, we have sequenced and analyzed the PB2 genes of five influenza virus isolates obtained from three affected states (Gujarat, Madhya Pradesh and Maharashtra) in India during the outbreaks. In the phylogenetic analysis, the Indian isolates were grouped in the mixed-migratory bird sub-lineage of the Eurasian lineage. From the phylogenetic tree, it is evident that viruses were probably introduced to India from China via Europe because they share a direct ancestral relationship with the Indian isolates. The virus might have spread through migratory waterfowls that survived the HPAI H5N1 infection. These viruses were able to replicate in cultured cells of avian and mammalian hosts and posses lysine at position 627 of the PB2 protein, indicating that they might be able to cross the host barrier to infect mammals.

Anti-ulcer activity of Adhatoda vasica Nees

Adhatoda vasica Nees (Acantheceae), commonly known as Vasaka, is a well-known plant in indigenous systems of medicine and is used for its beneficial effects, particularly in bronchitis. The present investigation was carried out to study the anti-ulcer activity of Adhatoda vasica leaves using two ulcer models (1) Ethanol-induced, and (2) Pylorus ligation plus aspirin-induced models. Adhatoda vasica leaf powder showeda considerable degree of anti-ulcer activity in experimental rats when compared with a control. The highest degree of activity (80%) was observed in the ethanol-induced ulceration model. Results of the study suggest that in addition to its classically established pharmacological activities, the plant also has immense potential as an anti-ulcer agent of great therapeutic relevance.

HPTLC method for the estimation of alkaloids of Cinchona officinalis stem bark and its marketed formulations

We report a sensitive method for the estimation of quinine (Qn), cinchonine (Cn), and cinchonidine (Cnd) and a new method based on fluorescence enhancement and detection and quantification of quinidine (Qnd) from Cinchona stem bark and its formulations, using HPTLC. Standard solutions of Qn, Qnd, Cn, and Cnd were applied on precoated HPTLC plates and developed with chloroform/diethylamine (9.6:1.4 v/v). The plates were scanned and quantified at 226 nm for Qn, Cn, Cnd and for Qnd at 366 nm in fluorescence and reflectance mode ([symbol: see text] K400 filter). The method was validated for precision, accuracy and repeatability. Further, the stem bark of Cinchona officinalis and some herbal and homeopathic formulations were evaluated for their individual alkaloid content applying the developed method.

Sensitive high-performance thin-layer chromatographic method for the estimation of diospyrin, a tumour inhibitory agent from the stem bark of Diospyros montana Roxb

Diospyrin, a tumour inhibitory agent from the stem bark of Diospyros montana was isolated and characterised. A sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the estimation of diospyrin. The method was validated for precision (intra- and inter-day), repeatability and accuracy. The method was found to be precise, with the RSDs for intra-day in the range of 0.72-1.85% and RSDs for inter-day in the range of 1.06-2.95%, for different concentrations. Instrumental precision and repeatability of the method were found to be 0.086 and 0.937 (% CV), respectively. Accuracy of the method was checked by performing the recovery study at two levels and average percentage recovery was found to be 97.87%. The developed HPTLC method was adopted for the estimation of diospyrin content of the stem bark of D. montana from different regions, which varied from 0.35 to 0.47% (w/w) in the samples.

A rapid method for isolation of andrographolide from andrographis paniculata nees (kalmegh)

A simple and rapid method for isolation of andrographolide from the leaves of Andrographis paniculata is reported. This involves extraction of the leaf powder by cold maceration in a 1:1 mixture of dichloromethane and methanol and isolation of andrographolide directly from the resulting extract by recrystallisation. The identity of the compound was confirmed through IR, UV, mass and melting point, and co-chromatography with a reference standard on TLC. The purity of the compound was confirmed by TLC, UV absorption spectrum, HPLC and differential scanning calorimetry, the latter of which gave the melting point of andrographolide as 235.3°C.