Cashmirins A and B, new antifungal and urease inhibitory prenylated coumarins from Sorbus cashmiriana

Abstract Cashmirins A (1) and B (2), new prenylated coumarins, have been isolated from the EtOAc- soluble fraction of the whole plant of Sorbus cashmiriana Hedlung, Monog. along with seselin (3), scopoletin (4), 3-hydroxyxanthyletin (5) and luteolin (6), reported for the first time from this species. Their structures were elucidated by spectroscopic techniques including MS, 1D and 2D NMR spectroscopy. Both new compounds 1 and 2 were investigated for biological activities and showed significant antifungal and urease inhibitory activities. Compounds 1 and 2 exhibited significant activity against Aspergillus flavus, Macrophomina phaseolina, Trichophyton simii, Trichophyton schoenleinii, and Pseudallescheria boydri. Both compounds also exhibited significant inhibitory activity against Jack bean urease with IC50 values of 28.2±0.12 µM and 30.3±0.18 µM, respectively compared to thiourea used as positive control.

Antibacterial activity of Hibiscus rosa-sinensis L. red flower against antibiotic-resistant strains of Helicobacter pylori and identification of the flower constituents

Utilization of plant resources for treatment of Helicobacter pylori infections is one of the appealing approaches as rapid emergence of antibiotic-resistant strains is occurring throughout the world. Ethanol extract and its fractions from Hibiscus rosa-sinensis red flower were assessed for antibacterial and urease inhibitory activities towards forty-three clinical strains and two reference strains of H. pylori. The ethyl acetate fraction exhibited the most potent bacteriostatic activity with minimum inhibitory concentrations (MICs) of 0.2-0.25 mg/mL and minimum bactericidal concentrations (MBCs) of 1.25-1.5 mg/mL against all test strains, including forty-three strains resistant to one to four antibiotics, azithromycin (MICs, 8-256 µg/mL), erythromycin (MICs, 8-128 µg/mL), levofloxacin (MICs, 8-256 µg/mL), and/or metronidazole (MICs, 8-256 µg/mL). The fraction had similar antibacterial activities toward these test strains suggesting the preparation and the antibiotics do not have a common mechanism of anti-H. pylori activity. The fraction also had stronger effects on biofilm formation, morphological conversion, and urease activity of H. pylori than the other fractions and the ethanol extract. These flower preparations were non-toxic to three human cell lines, and nine compounds were also isolated and identified from the ethyl acetate fraction. In vivo research needs to be conducted to confirm the potential usefulness of H. rosa-sinensis flower and its constituents for effective prevention and treatment of H. pylori disease.

Biological activity of synthesized 5-{1-[(4-chlorophenyl)sulfonyl]piperidin-4-yl}-2-mercapto-1, 3, 4-oxadiazole derivatives demonstrated by in silico and BSA binding studies

We synthesized a series of compounds bearing pharmacologically important 1,3,4-oxadiazole and piperidine moieties. Spectral data analysis by 1H-NMR, 13C-NMR, IR and EI-MS was used to elucidate the structures of the synthesized molecules. Docking studies explained the different types of interaction of the compounds with amino acids, while bovine serum albumin (BSA) binding interactions showed their pharmacological effectiveness. Antibacterial screening of these compounds demonstrated moderate to strong activity against Salmonella typhi and Bacillus subtilis but only weak to moderate activity against the other three bacterial strains tested. Seven compounds were the most active members as acetyl cholinesterase inhibitors. All the compounds presented displayed strong inhibitory activity against urease. Compounds 7l, 7m, 7n, 7o, 7p, 7r, 7u, 7v, 7x and 7v were highly active, with respective IC50 values of 2.14±0.003, 0.63±0.001, 2.17±0.006, 1.13±0.003, 1.21±0.005, 6.28±0.003, 2.39±0.005, 2.15±0.002, 2.26±0.003 and 2.14±0.002 µM, compared to thiourea, used as the reference standard (IC50 = 21.25±0.15 µM). These new urease inhibitors could replace existing drugs after their evaluation in comprehensive in vivo studies.

Preliminary screening for in vitro anti-enteritic properties of a traditional herb Dillenia pentagyna Roxb. fruit extracts

Objective: To explore anti-enteric properties of Dillenia pentagyna Roxb. (D. pentagyna) fruit extract fractions of different polarities by comparative antimicrobial activity against municipal sewage microflora and to assess its urease inhibition potential. Methods: Different polar fractions of D. pentagyna fruit extracts were studied by antimicrobial susceptibility test with several adjustments in this resource limited setup. Tests were done against municipal sewage microbes at various bacterial load (initially with 1.0 McFarland followed by 1.5 McFarland) using basal (nutrient agar) and selective medium (MacConkey's agar with and without supplementation of 5% NaCl). All assays statistically scaled with a gradient for uniformity and comparison with ciprofloxacin standard. Fraction with highest activity was studied for urease inhibition potential by kinetic method. Results: DP-47 separated by 30% ethyl acetate (EtOAc) in CHCl

Preliminary screening for in vitro anti-enteritic properties of a traditional herb Dillenia pentagyna Roxb. fruit extracts

OBJECTIVE@#To explore anti-enteric properties of Dillenia pentagyna Roxb. (D. pentagyna) fruit extract fractions of different polarities by comparative antimicrobial activity against municipal sewage microflora and to assess its urease inhibition potential.@*METHODS@#Different polar fractions of D. pentagyna fruit extracts were studied by antimicrobial susceptibility test with several adjustments in this resource limited setup. Tests were done against municipal sewage microbes at various bacterial load (initially with 1.0 McFarland followed by 1.5 McFarland) using basal (nutrient agar) and selective medium (MacConkey's agar with and without supplementation of 5% NaCl). All assays statistically scaled with a gradient for uniformity and comparison with ciprofloxacin standard. Fraction with highest activity was studied for urease inhibition potential by kinetic method.@*RESULTS@#DP-47 separated by 30% ethyl acetate (EtOAc) in CHCl3 from CHCl3 extract had slightly higher antimicrobial potency (y=0.758x+7.571) as dissolved in methanol than in dimethylsulfoxide (y=0.300x+6.000). EtOAc extract fractioned by 10% methanol in EtOAc (DP-43) was more potent antimicrobial (y=1.428x+8.392) and soluble in water. Butanol extract fractioned by water (DP-50) showed highest antimicrobial potency (y=3.384x+2.000) than both DP-47 and DP-43 in disk diffusion assays. In higher microbial load DP-50 was potent antimicrobial (y=1.538x+3.000) and completely inhibited any vegetative growth at lower load of 0.5 McFarland. In selective environment DP-50 was effective (y=1.076x+7.500 in MacConkey's, y=1.307x+6.000 in 5% NaCl supplemented). It was evident that enteric pathogens may not easily develop resistance against DP-50 and at high concentration it inhibited urease activity by 94.87%. The standard inhibition by thiourea (1%) is 33.914%.@*CONCLUSIONS@#Highly polar fraction of D. pentagyna Roxb. fruit extract DP-50 have potential antimicrobial activity against sewage microflora in basal and selective culture indicating its potential against non-fastidious, coliforms and Vibrio pathogens. Urease inhibition indicates efficacy against Helicobactor pylory.

Potential Use of Bischofia javanica as an Active Ingredient of Functional Foods and Cosmeceutical Products Possessing Hyaluronidase, Collagenase, Tyrosinase and Urease Inhibitory Effects / 日本補完代替医療学会誌

<i>Bischofia javanica</i> leaf extract exhibited inhibitory activities against hyaluronidase, collagenase, tyrosinase and urease, suggesting that it is useful as an active ingredient for functional foods and cosmeceutical products. In particular, its 50% inhibitory concentration for hyaluronidase was comparable to that of disodium cromoglycate, which is a well-known hyaluronidase inhibitor used as an anti-inflammation and anti-allergy agent. In addition, the extract also inhibited urease with the almost the same potential as acetohydroxamic acid, which is reported to suppress <i>Helicobacter pylori</i>-induced gastritis by inhibiting urease.<br>