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This is the first report on the development and validation of high-performance thin-layer chromatography (HPTLC) method for simultaneous analysis of five antipsychotic and medicinally important β-carboline alkaloids (βCAs), namely, harmalol, harmaline, harmine, harmane and norharmane. These βCAs occurs in both plant and animal system including human being. In the present investigation, their best separation was achieved using an optimized mobile phase, chloroform: methanol: glacial acetic acid (7.8:2.2:0.2, v / v / v) on aluminum TLC plates precoated with silica gel 60 F254. The quantification was performed by densitometric scanning in fluorescence mode at 366 nm. The calibration curves were drawn using linear regression, plotted over the range 25–250 ng band−1 of standard βCAs with correlation coefficient (R 2) between 0.97 and 0.992. Accuracy in terms of recovery (83.95–112.40%), repeatability of application (0.61–2.42%), repeatability of measurement (1.94–3.05%) and intermediate precision (0.62–11.16%) of developed method were simultaneously determined. The limit of detection and limit of quantification were between 4.95–6.59 and 16.50–21.93 ng band−1, respectively. The method was validated according to ICH guidelines and was simple, cost-effective, precise, sensitive and specific for the determination of βCAs in herbs, Fagonia schweinfurthii, Peganum harmala and Tribulus terrestris. The developed HPTLC method would have importance in forensic and industrial chromatographic analysis and fingerprinting of various herbs and drug formulations containing βCAs. [ABSTRACT FROM AUTHOR]

Macroalgae associated bacteria are the major source of polysaccharide hydrolyzing enzymes for efficient bioutilisation of macroalgal biomass. In this study, extracellular porphyranase, PB1 isolated from a macroalgae associated bacterium, Bacillus sp. NIOA284 was purified and characterized for hydrolysis of porphyran into porphyran oligosaccharides. The enzyme, PB1 showed the highest activity at the optimum conditions; the temperature of 35 ºC, pH 7 and 0.4 NaCl with 10 mM CoCl 2. The structural characterization of the enzymatically produced POS using NMR spectroscopy and HRMS spectrometry showed that the enzyme acted on porphyran as β-porphyranase and produced di, tri and tetra saccharides. The bioactive potential of POS was determined based on its radical scavenging and prebiotic activity. Results show that POS exhibited higher antioxidant activity than parent porphyran and fructooligosaccharides. It was also capable to proliferate the beneficial gut bacterium Lactobacillus acidophilus and L. bulgaricus , it recorded a prebiotic activity score equivalent to model prebiotic compound fructooligosaccharides. Results show that the enzymatically produced POS has combined antioxidant and prebiotic activity. This highlights the significance of macroalgae associated bacteria as a source of enzymes capable of hydrolyzing polysaccharides into simple bioactive oligosaccharides for efficient management of chronic disorders caused due to oxidative stress. [Display omitted] • Porphyranase was purified and characterized from a macroalgal associated bacteria. • Oligosaccharides were produced from porphyran through enzymatic hydrolysis. • Porphyran oligosaccharides demonstrated efficient free radical scavenging activity. • Porphyran oligosaccharides exhibited prebiotic activity higher than porphyran. • Bioactive oligosaccharides are efficient for management of oxidative stress. [ABSTRACT FROM AUTHOR]

Drug resistance and relapse after treatment of visceral leishmaniasis (VL) with the chemotherapeutic drugs has impeded the VL elimination programme especially, in the endemic region of Bihar, India. Currently, Antimonials (Sbv) have been rendered obsolete (Bihar) as frequent treatment failure and relapse in Sbv treated patient's warrants greater vigilance and attention to the limited drugs. A clinical isolate of L.donovani obtained from an Amphotericin B (AmB) relapse patient was evaluated for its susceptibility to AmB and a hyperlipidemic drug Guggul. The evaluation of susceptibility or resistance to any drug still relies on in vitro assay on promastigote and amastigote stages of Leishmania spp. as there are no validated markers which can ascertain drug resistance in Leishmania. The anti-promastigote effect of AmB and Guggul were demonstrated by significant cellular and morphological changes exhibiting apoptosis-mediated cell death. To further illustrate the molecular mechanism of the parasite's response upon exposure to either AmB and Guggul, sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS) for quantitative proteomics analysis was performed along with computational data analysis; revealing considerable differences in the proteome profiles which could be regarded as putative markers for resistance or drug targets for development of therapeutic antileishmanials. [ABSTRACT FROM AUTHOR]

The present study provides comprehensive proteomics analyses of the response of L. donovani parasite to pharamacological stress in vitro. Identification of differentially expressed proteins with associated molecular functions and metabolic pathways, clearly provides an insight into the potential mechanism of the antileishmanial effects as well as a comparative response of the parasite to Guggul and AmB. Treatment of parasite with AmB results in an enhanced modulatory mechanism to counteract the drug induced stress which may have contributed to relapse. In the case of Guggul treatment, an effective antipromastigote activity was observed, which is being reported for the first time. Thus, a deeper understanding of the molecular pathways in the Leishmania parasite in response to pharmacological stress would help in designing novel and effective strategies in targeting the key molecules essential for parasite survival. It will also help in screening of new lead molecules targeting these vital pathways which could be used as an adjunct therapy along with the limited repertoire of antileishmanial drugs. Unlabelled Image • SWATH-MS quantitative proteomics reveals differential expression of proteins under pharmacological stress in L. donovani. • Antipromastigote effect of Guggul via apoptosis not reported hitherto. • Upregulation of mitochondrial and antioxidant enzymes to counteract AmB induced stress in L. donovani. • PPI network analysis; identification of hub proteins and functional annotation of DEPs. [ABSTRACT FROM AUTHOR]