120 research outputs found
Thin-layer chromatographic separations of lantadenes, the pentacyclic triterpenoids from lantana ( Lantana camara) plant
Seven solvent systems of varying suitability are reported for the thin-layer chromatographic separation of lantadenes isolated from the heptatotoxic plant
Lantana camara var.
aculeata. Hexane-methanol-ethyl acetate (85:10:5) was found to be the most suitable for the separation of lantadene A, B, C, D, reduced lantadene A and reduced lantadene B. Lantadenes could be detected on thin layers of silica gel G using Liebermann-Burchard reagent, vanillin-sulphuric acid and primulin sprays
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Determination of Both Tannin and Protein in a Tannin-Protein Complex
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Recent advances in the role of neutrophils and neutrophil extracellular traps in acute pancreatitis
Pathophysiology of Experimental Pancreatitis
Acute pancreatitis is a significant cause of morbidity, mortality, and hospitalization worldwide. The incidence of acute pancreatitis is on the rise. Owing to an incomplete understanding of the pathophysiology of acute pancreatitis, no targeted therapy is available for this disease. Hence, currently, the treatment revolves largely around supportive measures. Our limited understanding of the pathophysiology of acute pancreatitis is based on studies using experimental animal models and pancreatic cell‐based in vitro experiments. Several experimental models of acute pancreatitis have been developed in different species. However, lately most of the studies have been performed in murine models, for multiple reasons, the most important of which is the availability of strains of mice with different gene deletions. Although studies on these murine models have provided useful information on the initiating events of acute pancreatitis, these models do not mimic the progression of human pancreatitis. Studies suggest that acute pancreatitis begins in the pancreatic acinar cells. Premature activation of zymogens, inhibition of secretion, and activation of inflammatory pathways are observed in the pancreatic acinar cells within minutes of pathologic provocation. Other events such as increased endoplasmic reticulum stress, loss of mitochondrial potential, and autophagy dysfunction are also observed in pancreatic acinar cells, early on during acute pancreatitis. Eventually, these events lead to pancreatic acinar cell death and spread of inflammation to other organs. Uncontrolled systemic inflammation can lead to multiorgan failure. Studies in experimental models suggest that intra‐acinar trypsin activation, which has been considered central to the pathogenesis of acute pancreatitis for decades, results from colocalization of zymogens and lysosomes. Perturbed calcium signaling is believed to be involved in initiating pathologic changes. Although inhibition of trypsin provides significant protection from acinar cell death, recent studies suggest that events other than trypsin activation play a central role in pathogenesis of acute pancreatitis. Emerging evidence suggests that cathepsin B, in addition to playing an important role in trypsin activation, can play a role in activation of cell death pathways. Furthermore, data suggest that trypsin‐independent inflammation plays an important role in local and systemic injury. The ability to modulate the pathophysiology and progression of inflammation might improve the outcomes for patients
A triterpenoid acid, lantadene D from Lantana camara var. Aculeata
A novel triterpenoid, lantadene D, has been isolated from the leaves of the hepatotoxic plant Lantana camara var. aculeata. Its structure has been established as 22-β-isobutyroyloxy-3-oxoolean-12-en-28-oic acid
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Reversed-phase high-performance liquid chromatographic separation and quantification of lantadenes using isocratic systems
Isocratic systems of varying suitability are reported for reversed-phase HPLC of lantadenes, the pentacyclic triterpenoids from the hepatotoxic plant
Lantana camara var.
aculeata. The column used was a Nova-Pak C
18 (250 × 4.6 mm). The detection was at 210 nm and 240 nm. The mobile phase acetonitrile-water-acetic acid (80:20:0.01) provided baseline separation of all the lantadenes except lantadenes A and C. The mobile phase methanol-water-acetic acid (85:15:0.01) also provided resolution of all the lantadenes but the retention time windows were very broad. The mobile phase methanol-acetonitrile-water-acetic acid (68:20:12:0.01) has been found to be the most suitable for the separation and quantitation of lantadenes
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Protein-binding capacity of microquantities of tannins
The physiological effect of tannins is studied in terms of their protein-binding or precipitation capacity. A number of assays based on binding of hemoglobin or bovine serum albumin (BSA) and subsequent determination of unbound protein in supernatant or tannin in a protein-tannin complex are available but with various limitations. These methods are unable to estimate protein-binding capacity, if the quantity of tannin available is low. In the method reported here, tannins or other phenolics were applied on chromatography paper and reacted with BSA and unbound BSA was washed off. The protein in the tannin-protein complex was measured spectrophotometrically after staining with Ponceau S. It required microquantities of sample. Using this method the protein-binding capacity of total leaf extract and hydrolyzable and condensed tannins of
Quercus incana, Q. semecarpofolia, and
Q. dilatata was determined. The protein binding capacities of ellagic acid and quercetin (μg BSA/mg) were 297.3 and 78.0, respectively
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Molecular structure, polymorphism, and toxicity of lantadene a, the pentacyclic triterpenoid from the hepatotoxic plant Lantana camara
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