Evaluation of some biological activities of Abelia triflora R Br (Caprifoliaceae) constituents

Purpose: To investigate the antioxidant, anti-inflammatory, antidiabetic,  cardiovascular and cytotoxic activities of the leaf extract and major compounds isolated from Abelia triflora R. Br. (Caprifoliaceae)Methods: The chloroform soluble fraction of A. triflora leaves was subjected to several column chromatographic separations to isolate its constituents.  Anti-inflammatory and antioxidant activities were determined in terms of the ability to inhibit NF-kB, iNOS activity and lipoxygenase enzyme, and to decrease oxidative stress in HepG2 cells. Antidiabetic and cardiovascular activities were determined by screening for peroxisome proliferator-activated receptor alpha (PPARα) and PPARɣ agonistic activities. In vitro cytotoxic activity was determined against a set of four human cancer cell lines (SK-MEL, KB, BT-549, SK-OV-3) and two  non-cancerous kidney cell lines (LLC-PK1 and VERO). Cell viability was measured by neutral red assay.Results: Three triterpene acids were isolated from the chloroform fraction namely; ursolic acid (4), 2, 3-dihydroxy ursolic acid (5) and 2, 3, 21-trihydroxy ursolic acid (6). The results showed that ursolic acid exhibited potent inhibition of lipoxygenase enzyme and iNOS (inducible nitric oxide synthase) activity with IC50 (half-maximal inhibitory concentration) value of 13.0 μg/mL, compared to parthenolide positive standard (IC50, 0.3μg/mL); furthermore, it inhibited NF-kB (nuclear factor-kappa B) with IC50 of 25.0 μg/mL, compared to parthenolide (positive standard, (IC50, 0.5 μg/mL). Also, ursolic acid possessed the highest cytotoxic effect against the three cell lines, SK-MEL (IC50, 14.5 μg/mL), BT-549 (IC50, 16.0 μg/mL) and SK-OV-3 (IC50, 12.5 μg/mL). Only 2,3-dihydroxy ursolic acid activated PPARɣ (1.5-fold at 25 μM), compared to rosiglitazone (positive standard, 3.7 fold at 10 μM)Conclusion: Among the investigated compounds, ursolic acid exhibited the highest anti-inflammatory and cytotoxic activities, while 2,3-dihydroxy ursolic acid demonstrated antidiabetic activity via activation of PPARɣ.Keywords: Abelia triflora, Anti-inflammatory, Antidiabetic, Cardiovascular activity, Antioxidant, Cytotoxi

Trichosides A and B, new withanolide glucosides from <i>Tricholepis eburnea</i>

<p>Trichosides A (<b>1</b>) and B (<b>2</b>), new withanolide glucosides, have been isolated from the <i>n</i>-butanolic fraction of the 75% methanolic extract of aerial parts of <i>Tricholepis eburnea</i>. Their structures were elucidated through spectroscopic analysis including ESI-MS, 2D NMR and acid hydrolysis.</p

Eburneolins A and B, new withanolide glucosides from <i>Tricholepis eburnea</i>

<p>Eburneolins A (<b>1</b>) and B (<b>2</b>), new withanolide glucosides, have been isolated from the <i>n</i>-butanolic fraction of the 75% methanolic extract of aerial parts of <i>Tricholepis eburnea</i>. Their structures were elucidated through spectroscopic analysis including ESI-MS, 2D NMR and acid hydrolysis.</p

Adsorption of Remazol Brilliant Violet-5R from Aqueous Solution Using Sugarcane Bagasse as Biosorbent: Kinetic and Thermodynamic Studies

Sugarcane bagasse is an inexpensive and eco-friendly natural biosorbent for the removal of various organic pollutants. The adsorption of Remazol Brilliant Violet-5R (RBV-5R) dye on sugarcane bagasse (SCB) was studied. Biosorbent was characterized using EDX and FTIR. The effect of various experimental parameters, such as pH, biosorbent dosage, initial dye concentration, contact time, adsorption with shaking and without shaking, and the temperature, was optimized. At pH 6, maximum biosorption of 92.22% was achieved using 0.15 g of SCB. The equilibrium was attained within 30&ndash;40 min for the removal of RBV-5R. The initial dye concentration of 10 &micro;g/mL was determined as an optimum concentration for maximum removal of RBV-5R at 30 &deg;C. Langmuir and Freundlich adsorption isotherms were applied, and it was found that the biosorption of RBV-5R follows Freundlich adsorption isotherms. Kinetic studies were also carried out and it was found that the proposed method followed the pseudo-second-order kinetic model (R2 = 0.98). From desorption study, it was found that maximum desorption in the increasing order was obtained using ethanol, methanol, and 0.2 M sodium hydroxide (NaOH). The biosorption study was applied to actual textile waste effluent to pave way for the practical usage of this technology on a larger scale and the results were found effective

Adsorption of Remazol Brilliant Violet-5R from Aqueous Solution Using Sugarcane Bagasse as Biosorbent: Kinetic and Thermodynamic Studies

Sugarcane bagasse is an inexpensive and eco-friendly natural biosorbent for the removal of various organic pollutants. The adsorption of Remazol Brilliant Violet-5R (RBV-5R) dye on sugarcane bagasse (SCB) was studied. Biosorbent was characterized using EDX and FTIR. The effect of various experimental parameters, such as pH, biosorbent dosage, initial dye concentration, contact time, adsorption with shaking and without shaking, and the temperature, was optimized. At pH 6, maximum biosorption of 92.22% was achieved using 0.15 g of SCB. The equilibrium was attained within 30–40 min for the removal of RBV-5R. The initial dye concentration of 10 µg/mL was determined as an optimum concentration for maximum removal of RBV-5R at 30 °C. Langmuir and Freundlich adsorption isotherms were applied, and it was found that the biosorption of RBV-5R follows Freundlich adsorption isotherms. Kinetic studies were also carried out and it was found that the proposed method followed the pseudo-second-order kinetic model (R2 = 0.98). From desorption study, it was found that maximum desorption in the increasing order was obtained using ethanol, methanol, and 0.2 M sodium hydroxide (NaOH). The biosorption study was applied to actual textile waste effluent to pave way for the practical usage of this technology on a larger scale and the results were found effective

Quantifying Co–Zn contents for compositional tailoring of strontium W-type hexaferrites for useful applications

Structural, optical, dielectric, and magnetic characteristics of Sr–Ni–W hexaferrites were probed to justify their potential use in various applications. Sr1-xCoxZnyNi2-yFe16O27 (WHFs) ferrites were synthesized by the self-combustible sol-gel method. XRD analysis confirmed a single-phase material with different Co–Zn contents. Fourier transform infrared spectroscopic (400-4000 cm−1) analysis was performed. Variations in Raman intensities indicated the induction of local strain due to a mismatch of ionic radii. The energy band gap (1.879 eV) was calculated from photoluminescence spectra, indicating the semiconducting nature of materials. SEM images showed the presence of grains with hexagonal platelet morphology oriented irregularly, which is highly beneficial for microwave absorption. The high coercivity values indicated that the materials are magnetically hard. Magnetic analysis revealed the potential use of materials in high-storage applications. Dielectric properties were determined using a vector network analyzer within a frequency span (0–6 GHz), indicating materials' usefulness in constructing resonant circuits and MLCIs