Publications by authors named "Keshab Bhattarai"

, commonly known as Tulsi, is revered in Ayurveda for its extensive medicinal properties. However, there is a need to consolidate current knowledge on its phytochemical constituents and their pharmacological activities to identify potential areas for further research and drug development. This review aims to bridge this gap by providing a comprehensive analysis of the bioactive secondary metabolites found in , such as rosmarinic acid, oleanolic acid, luteolin, ursolic acid, and limonene, and their associated therapeutic effects.

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Lasso peptides are a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) that feature an isopeptide bond and a distinct lariat fold. A growing number of secondary modifications have been described that further decorate lasso peptide scaffolds. Using genome mining, we have discovered a pair of lasso peptide biosynthetic gene clusters (BGCs) that include cytochrome P450 genes.

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Inflammatory disorders are the prime contributor to public health issue and the development of more effective and safer anti-inflammatory drugs in addition to other therapeutic alternatives to treat inflammatory illnesses, particularly chronic inflammatory diseases, is one of the foremost current issues. In this regard, our present work is concerned with the synthesis of a new series of -alkyl/aralkyl/aryl derivatives () of 5-((-tolyloxymethyl)-4H-1,3,4-oxadiazole-2-ylthio)propionamide which was instigated by the successive conversions of -tolyloxyacetic acid into ester, hydrazide and 5-(-tolyloxymethyl)-4H-1,3,4-oxadiazole-2-thiol. The planned compounds () were attained by the reaction of 5-(-tolyloxymethyl)-4H-1,3,4-oxadiazole-2-thiol with variety of -alkyl/aralkyl/aryl electrophiles in potassium hydroxide and were characterized by FTIR, H-, C-NMR spectroscopy, EI-MS and HR-EI-MS spectrometry and probed for their inhibiting potential against soybean 15-lipoxygenase (15-LOX) enzyme.

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Lasso peptides are a class of ribosomally synthesized and post-translationally modified peptides (RiPPs) that feature an isopeptide bond and a distinct lariat fold. A growing number of secondary modifications have been described that further decorate lasso peptide scaffolds. Using genome mining, we have discovered a pair of lasso peptide biosynthetic gene clusters (BGCs) that include cytochrome P450 genes.

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The underlying correlation between the inflammation, innate immunity and cancer is extensively familiar and linked through a process mediated by three enzymes; cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 (CYP). The ever increase in the reported side effects of the antiinflammatory drugs against the targeted enzymes and the resistance developed afterwards compels the researchers to synthesize new effective molecules with safer profile. On the basis of these facts, our ongoing research on 1,3,4-oxadiazole derivatives deals with the synthesis of a new series of N-alkyl/aralky/aryl derivatives of 5-((p-tolyloxymethyl)-4H-1,3,4-oxadiazole-2-ylthio)acetamide (6a-o) which were developed by the sequential conversion of p-tolyloxyacetic acid (a) into ester (1) hydrazide (2) and 5-(p-tolyloxymethyl)-4H-1,3,4-oxadiazole-2-thiol (3).

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Two new ircinianin-type sesterterpenoids, ircinianin lactone B and ircinianin lactone C ( and ), together with five known entities from the ircinianin compound family (, -) were isolated from the marine sponge . Ircinianin lactones B and C ( and ) represent new ircinianin terpenoids with a modified oxidation pattern. Despite their labile nature, the structures could be established using a combination of spectroscopic data, including HRESIMS and 1D/2D NMR techniques, as well as computational chemistry and quantum-mechanical calculations.

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Lipoxygenases (LOXs) are a class of enzymes that catalyze the production of pro-inflammatory mediators, such as leukotrienes and lipoxins, via an arachidonic acid cascade as soon as they are released from the membrane phospholipids after tissue injury. In continuation of our efforts in search for new LOX inhibitors, a series of chlorophenyl-furfuryl-based 1,2,4-triazole derivatives were prepared and evaluated for their 15-LOX inhibitory activities. A simple precursor, 4-chlorobenzoic acid (), was consecutively transformed into benzoate (), hydrazide (), semicarbazide (), and -furfuryl 5-(4-chlorobenzyl)-4-1,2,4-triazole (), which when further merged with electrophiles () resulted in end products ().

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Lipoxygenases (LOXs) are a group of enzymes that catalyze the oxidation of polyunsaturated fatty acids and initiate the biosynthesis of secondary metabolites that are involved to control inflammation. In search of new and more potent LOX inhibitors, a series of new 3-(5-(4-chlorophenyl)-4-(2-furylmethyl)-1,2,4-triazole hybrids was prepared and screened for its LOX inhibitory potential. 4-Chlorobenzoic acid () was metamorphosed into -furfuryl-5-(4-chlorophenyl)-4-(2-furylmethyl)-1,2,4-triazole () via intermediates like benzoate (), hydrazide () and semicarbazide ().

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Plants have a pivotal role in ethnopharmacology, and their preparations are in use globally. However, getting down to the structure requires an effective workflow and mostly requires a time-consuming isolation process. Although bioassay-guided approaches are widely popular, they face a massive problem of rediscovery in recent times, especially in plant metabolomics.

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Epidemiological studies suggest that regular intake of soy isoflavone exerts a preventive effect on postmenopausal obesity and other forms of dysmetabolism. Estrogens inhibit eating behavior. Soy isoflavones may act as estrogen agonist in estrogen-depleted conditions, whereas they may either act as an estrogen antagonist or be ineffective in estrogen-repleted conditions.

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A chemical reinvestigation of the Indonesian strain sp. SHP 22-7 led to the isolation of three new pyrimidine nucleosides, along with six known analogues and zincphyrin. The structures of the new compounds (, , ) were elucidated by employing spectroscopic techniques (NMR, MS, CD, and IR) as well as enantioselective analyses of methyl branched side chain configurations.

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Scientists working in natural products chemistry have been enticed by the current advancements being made in the discovery of novel "magic bullets" from microbes homed to all conceivable environments. Even though researchers continue to face challenges funneling the novel bioactive compounds in the global therapeutic industries, it seems most likely that the discovery of some "hit molecules" with significant biomedical applications is not that far. We applaud novel natural products for their ability to combat the spread of superbugs and aid in the prevention of currently observed antibiotic resistance.

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Searching small molecules as an auspicious approach to develop new anti-inflammatory drugs is a challenge for the researchers especially by modifying active pharmacophoric groups in the targeted molecules. In the current work, a series of new S-alkyl/aralky derivatives (8a-h; 9a-h) of 2-(4-ethyl/phenyl-5-(1-phenylcarbamoylpiperidine)-4H-1,2,4-triazol-3-ylthio)ether were synthesized and assessed for their inhibitory action against the 15-lipoxygenase from soybean (15-sLOX). The basic precursor ethyl piperidine-4-carboxylate (a) was consecutively changed into phenylcarbamoyl derivative (1), hydrazide (2), semicarbazides (3/4) and N-ethyl/phenyl-5-(1-phenylcarbamoylpiperidine)-1,2,4-triazoles (5/6), which further in association with electrophiles (7a-h) promoted to the final products (8a-h; 9a-h).

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In search for new anti-inflammatory agents that inhibit the enzymes of arachidonic acid pathway as the drug targets, the present article describes the screening of 1,3,4-oxadiazole analogues against lipoxygenase (LOX) enzyme. The work is based on the synthesis of new N-alkyl/aralky/aryl derivatives (6a-o) of 2-(4-phenyl-5-(1-phenylcarbamoylpiperidine)-4H-1,3,4-oxadiazol-3-ylthio)acetamide which were obtained by the reaction of 1,3,4-oxadiazole (3) with various electrophiles (5a-o), in KOH. The synthesized analogues showed potent to moderate inhibitory activity against the soybean 15-LOX enzyme; especially 6g, 6b, 6a and 6l displayed the potent inhibitory potential with IC values 7.

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Context: species are prolific sources of bioactive secondary metabolites known especially for their antimicrobial and anticancer activities.

Objective: This study sought to isolate and characterize antioxidant molecules biosynthesized by sp. KTM18.

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Secondary metabolites synthesized by fungi have become a precious source of inspiration for the design of novel drugs. Indeed, fungi are prolific producers of fascinating, diverse, structurally complex, and low-molecular-mass natural products with high therapeutic leads, such as novel antimicrobial compounds, anticancer compounds, immunosuppressive agents, among others. Given that these microorganisms possess the extraordinary capacity to secrete diverse chemical scaffolds, they have been highly exploited by the giant pharma companies to generate small molecules.

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Hunting small molecules as anti-inflammatory agents/drugs is an expanding and successful approach to treat several inflammatory diseases such as cancer, asthma, arthritis, and psoriasis. Besides other methods, inflammatory diseases can be treated by lipoxygenase inhibitors, which have a profound influence on the development and progression of inflammation. In the present study, a series of new N-alkyl/aralky/aryl derivatives (7a-o) of 2-(4-phenyl-5-(1-phenylcarbamoyl)piperidine-4H-1,2,4-triazol-3-ylthio)acetamide was synthesized and screened for their inhibitory potential against the enzyme 15-lipoxygenase.

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In examining the role of institutions in resisting corruption and its impact on growth, most studies concentrate on the aggregate level and conclude that sound institutions enhance growth. We focus instead on varying dimensions of heterogeneous institutions in the presence of corruption and their interactive effect on stock returns in four emerging economies: Brazil, Russia, India, and China (BRIC). We pay particular attention to democratic accountability, bureaucratic quality, and law and order.

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Amid a rising threat of antimicrobial resistance in a global scenario, our huge investments and high-throughput technologies injected for rejuvenating the key therapeutic scaffolds to suppress these rising superbugs has been diminishing severely. This has grasped world-wide attention, with increased consideration being given to the discovery of new chemical entities. Research has now proven that the relatively tiny and simpler microbes possess enhanced capability of generating novel and diverse chemical constituents with huge therapeutic leads.

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We previously found that equol, a metabolite of intestinal bacterial conversion from soy isoflavone daidzein, has female-specific anorectic effects. In the present study, we used seven-week-old female ovariectomized (OVX) Sprague Dawley rats to test the hypothesis that the anorectic effect of dietary daidzein may be attributed to delayed gastric emptying. Results suggest that dietary daidzein delays gastric emptying and that it has an anorectic effect with residual gastric contents, but not without gastric contents.

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We previously found that daidzein decreased food intake in female rats. To understand the mechanism of anorectic action of dietary daidzein, it is necessary to determine distributions of daidzein and S-equol, a metabolite of intestinal bacterial conversion from daidzein, in the body. In the present study, we measured the concentrations of daidzein and S-equol in serum and bile in sham-operated and ovariectomized female rats fed a diet containing 150 mg/kg daidzein for 7 days.

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The promotion of muscle recovery after immobilization is important to preserve an optimum health status. Here, we examined the effect of dietary Alaska pollack protein (APP) on skeletal muscle weight after atrophy induced by hind limb immobilization using plaster immobilization technique. Rat left limb was casted with a wetted plaster cast under anesthesia.

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Two compounds, compounds 1 and 2, were isolated from Preussia sp. The molecular structures of both compounds were elucidated by analyzing one-dimensional (1D) and 2D nuclear magnetic resonance data along with high-resolution mass spectrometry data. Compound 1 was obtained as novel in structure, and compound 2 was recently reported elsewhere.

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We compared the effects of two major isoflavones, daidzein and genistein, on lipid metabolism in rats. Daidzein (150 mg/kg diet), genistein (150 mg/kg diet), daidzein and genistein (1:1, 300 mg/kg diet), or control diets were fed to 4 groups of 6-week-old ovariectomized (Ovx) and non-Ovx Sprague Dawley rats for 4 weeks. Dietary daidzein, but not genistein, reduced serum and hepatic total cholesterol levels significantly relative to that by the control group, regardless of whether the rats had undergone ovariectomy.

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We previously found that daidzein decreased food intake in female rats. The present study aimed to elucidate the relationship between dynamics of appetite-mediated neuropeptides and the anorectic effect of daidzein. We examined appetite-mediated gene expression in the hypothalamus and small intestine during the 3 meals per day feeding method.

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