Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 12 de 12
1.
ACS Omega ; 9(19): 21545-21556, 2024 May 14.
Article En | MEDLINE | ID: mdl-38764647

Functionalization of room temperature liquids based on disubstituted imidazolium ionic liquids represents a promising avenue for tailoring their tunable physicochemical properties and expanding their potential application as green solvents to capture carbon dioxide as a greenhouse gas. In this work, new hydroxyl functionalized imidazolium ionic liquids were prepared from condensation of ethanolamine with glyoxal and formalin in the presence of acetic acid as catalyst. The chemical modification of the hydroxyl groups with epichlorohydrine added new hydroxylpropanoxychloride groups on the imidazolium cation that were quaternized with N-methylimidazolium chloride to produce new imidazolium acetate ionic liquids. The chemical structures, thermal stability, and thermal characteristics of the prepared imidazolium ionic liquids were evaluated. The incorporation of functionalized 1-chloro-2-hydroxypropanoxy and N-methylimidazolium chloride groups into the chemical structure of the imidazolium cations improved the thermal properties of the prepared ionic liquids. The application of the prepared ionic liquids as pure or mixed solvents with saline water to capture CO2 under atmospheric and 55.2 bar pressures was evaluated at room temperature. The data indicate that the prepared ionic liquids have superior CO2 adsorption/desorption rate in short time during 30 and 15 min and that their CO2 capture efficiency increased from 6.2 to 16.8 molCO2/kgIIL and from 9.1 to 20.0 molCO2/kgIIL at atmospheric and 55.2 bar pressures, respectively.

2.
Front Chem ; 10: 1078163, 2022.
Article En | MEDLINE | ID: mdl-36505739

A series of pyrazolyl-s-triazine compounds with an indole motif was designed, synthesized, and evaluated for anticancer activity targeting dual EGFR and CDK-2 inhibitors. The compounds were tested for cytotoxicity using the MTT assay. Compounds 3h, 3i, and 3j showed promising cytotoxic activity against two cancer cell lines, namely A549, MCF-7, and HDFs (non-cancerous human dermal fibroblasts). Compound 3j was the most active candidate against A549, with an IC50 of 2.32 ± 0.21 µM. Compounds 3h and 3i were found to be the most active hybrids against MCF-7 and HDFs, with an IC50 of 2.66 ± 0.26 µM and 3.78 ± 0.55 µM, respectively. Interestingly, 3i showed potent EGFR inhibition, with an IC50 of 34.1 nM compared to Erlotinib (IC50 = 67.3 nM). At 10 µM, this candidate caused 93.6% and 91.4% of EGFR and CDK-2 inhibition, respectively. Furthermore, 3i enhanced total lung cancer cell apoptosis 71.6-fold (43.7% compared to 0.61% for the control). Given the potent cytotoxicity exerted by 3i through apoptosis-mediated activity, this compound emerges as a promising target-oriented anticancer agent.

3.
Saudi J Biol Sci ; 29(2): 1191-1196, 2022 Feb.
Article En | MEDLINE | ID: mdl-35197786

Xanthones C-glycosides are plants secondary metabolites with diverse biological activities. Among the C-glycoside xanthones, the mangiferin (MF) is of widespread occurrence in plants while isomangiferin (IsoMF) is not very common. For the present study mangiferin (MF) and isomangiferin (IsoMF) were isolated from Dryopteris ramosa. The antibacterial potential of MF and IsoMF was evaluated by using agar well diffusion method while cytotoxic properties of MF and IsoMF were assessed by brine shrimp lethality test (BSLT). The antibacterial potential of MF and IsoMF increases in dose dependent manner. The minimum inhibitory concentration (MIC) indicated strong antibacterial potential of MF against Salmonella setubal (125 µg/mL) and Bacillus subtilis (125 µg/mL) while MF showed weak antibacterial potential against Escherichia coli (500 µg/mL). On the other hand the IsoMF showed better antibacterial potential against all the tested strain including Escherichia coli (MIC = 250 µg/mL). The MF and IsoMF showed poor cytotoxicity towards Brine shrimp nauplii as indicated by their LD50 (969.77 ± 0.67 and 768.92 ± 0.81 µg/mL respectively). The present study has highlighted the antibacterial potential of MF and IsoMF. Further evaluation of these two isomeric compounds may prove to be the future remedies for various bacterial infections and other human ailments.

4.
Saudi J Biol Sci ; 29(1): 88-95, 2022 Jan.
Article En | MEDLINE | ID: mdl-35002397

Citrus black rot disease being caused by Alternaria citri is a major disease of citrus plants with 30-35% economic loss annually. Fungicides had not been effective in the control of this disease during last few decades. In the present study, antifungal role of green synthesized zinc oxide (ZnO) and copper oxide (CuO) nanoparticles (NPs) were studied against Alternaria citri. Alternaria citri was isolated from disease fruits samples and was identified by staining with lacto phenol cotton blue. Furthermore, CuO and ZnO NPs were synthesized by utilizing the lemon peels extract as the reducing and capping agent. Nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. From the XRD data, the calculated size of CuO NPs was to be 18 nm and ZnO NPs was16.8 nm using Scherrer equation. The SEM analyses revealed the surface morphology of all the metal oxide NPs synthesized were rounded, elongated and or spherical in the shape. The zone of inhibition was observed to be 50 ± 0.5 mm by CuO NPs, followed by 51.5 ± 0.5 mm by ZnO NPs and maximum zone of antifungal inhibition was observed to be 53 ± 0.6 mm by mix metal oxide NPs. The results of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the synthesized nanoparticles showed that at the certain concentrations (80 mg ml-1), these NPs were capable of inhibiting the fungal growth, whereas above that specified concentrations (100 mg ml-1), NPs completely inhibited the fungal growth. Based on these findings, the green synthesized NPs can be used as alternative to fungicide in order to control the citrus black rot disease.

5.
Saudi J Biol Sci ; 29(1): 287-295, 2022 Jan.
Article En | MEDLINE | ID: mdl-35002421

Endophytes are microorganisms residing within plant tissues. Bacterial endophytes are important sources for production of pharmaceutically important metabolites. Berberis lycium is an important medicinal plant and there exist no report regarding isolation and determination of bioactive potential of its bacterial endophytes. Therefore the present study was aimed to isolate and identify bacterial endophytes from Berberis lycium. The study resulted in isolation of 20 strains of bacterial endophytes. Based on their antibacterial activity three strains were identified as Bacillus cereus (LBL6), Bacillus thuringiensis (SBL3) and Bacillus anthracis (SBL4) on basis of 16SrRNA gene using universal primers. Crude ethyl acetate extracts of LBL6, SBL3 and SBL4 were further evaluated for antioxidant and antifungal activities. Moderate antioxidant activity (56 %) at a concentration of 1000 µg/mL was observed for LBL6 followed by 45 and 43 % activity by SBL4 and SBL3 respectively. Significant antifungal activity was observed against Aspergillus niger (60 %) and Aspergillus flavus (56 %) at concentration of 4 mg/mL of SBL3 and SBL4 respectively. GCMS analysis of extract (LBL6) exhibited presence of 12 bioactive secondary metabolites corresponding to antimicrobial, antifungal, antioxidant, antitumor and anticancer activities. In conclusion, present study highlighted the importance of Berberis lycium to host diverse bacterial endophytes of pharmaceutical importance.

6.
Saudi J Biol Sci ; 29(1): 472-479, 2022 Jan.
Article En | MEDLINE | ID: mdl-35002443

Bidens bipinnata is widely utilized medicinal plant for treatment of diseases like malaria, sore throat, acute nephritis and dysentery. However, despite its traditional uses Bidens bipinnata is not widely explored for its antimicrobial effect. Thus, the current study is aimed to form antimicrobial activity report of Bidens bipinnata extracts, along with isolation and evaluation of antibacterial activity of the isolated compounds through bioassay-guided purification. Hexane extract of its leaves has appeared to be most active thus it is exposed to automated column chromatography. Further purification using High-performance liquid chromatography has led to isolation of active peaks, identified by Gas Chromatography-mass spectrometry, as 16-Pregnenolone and 9-Octadecenoic acid (Z)-, methyl ester. Their antimicrobial activity was confirmed via broth dilution procedure on Staphylococcus aureus, 16-Pregnenolone revealed a strong antimicrobial activity with MIC50 of 72 µg/mL whereas 9-Octadecenoic acid (Z)-, methyl ester display an MIC50 of >250 µg/mL. Present study is the first report on isolation of these compounds from Bidens bipinnata.

8.
Saudi J Biol Sci ; 28(11): 6432-6440, 2021 Nov.
Article En | MEDLINE | ID: mdl-34764760

The emergence of multidrug resistance in pathogenic bacteria limits the utilization of available antibiotics. The development of alternate options to treat infectious diseases is the need of the day.The present study was aimed to synthesize, characterize and evaluate the bioactive properties of silver nanoparticles. Endophytic bacterium Bacillus cereus (MT193718) isolated from Berberis lycium was used to synthesize biocompatible silver nanoparticles. Antibacterial properties of AgNPs were evaluated against clinically isolated multidrug-resistant strains of Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae. AgNPs indicated significant antibacterial activity against S. aureus and K. pneumoniae fwith a zone of inhibition of 17 and 18 mm at a concentration of 1000 µg/ mL with minimum inhibitory concentration of 15.6 and 62.5 µg/mL respectively. Significant antioxidant activity with an IC50 value of 9.5 µg/mL was recorded. Biosynthesized AgNPs were found compatible with red blood cells at a concentration of 31.5 µg/ml with no clumping of erythrocytes. The study suggested that AgNPs synthesized by the endophytic bacterium Bacillus cereus are biologically active and can be used as antioxidant and antibacterial agents against drug-resistant bacteria.

9.
Saudi J Biol Sci ; 28(10): 5841-5848, 2021 Oct.
Article En | MEDLINE | ID: mdl-34588899

Rice bran oil is known as wonder oil and it is the most important vegetable oil in Asia. Rice bran oil is extracted from bran that is the outer hard layer of rice. It is an emerging category in edible oil with a lot of nutritional properties and health benefits. Rice bran oil is heart-friendly, boosts up immunity, and prevents from other diseases occurring commonly in Pakistan. The current study aimed to stabilize rice bran oil through different probiotic isolates and to assess the nutritional content of rice bran oil after stabilization. The study was aimed to inactivate naturally occurring lipases that can hydrolyze oil into glycerol and free fatty acid which is a serious problem that gives it a rancid taste and smell. Antilipase activity was used to inactivate naturally occurring lipases that are a huge threat to the stabilization process. The fermentation process utilizes antilipase activity without affecting the nutritional value of oil. Lactobacillus strains were used for the stabilization of rice bran oil. Rice bran oil was extracted in the Soxhlet apparatus. The probiotic lab isolates Lactobacillus delbrueckii S2, Lactobacillus casei S5 and Lactobacillus plantarum S13 were applied to it to increase its shelf life and prevent oxidative rancidity. The extraction temperature of rice bran oil was maintained above 40 °C to inhibit lipase activity. Rice bran oil samples were stored at refrigeration temperature to arrest lipase activity. Probiotics maintained acidic pH to keep oil stabilization. Qualitative analysis was done to confirm rice bran oil stabilization. Determination of Free Fatty Acid (FFA) and saponification value confirmed that oxidative rancidity of rice bran oil was controlled by probiotics. FFA count was less than 10% and Saponification Value (SV) was 180. GC analysis was performed to analyze the FFA profile. Gas Chromatography results have shown 3 fatty acids. Statistical analysis has shown non-significant effect on different incubation temperatures of Lactobacillus isolates. Among the biological methods of stabilization, the use of probiotics is a novel concept and recommended for commercial application.

10.
Saudi J Biol Sci ; 28(9): 5238-5249, 2021 Sep.
Article En | MEDLINE | ID: mdl-34466102

Water deficit stress negatively affects wheat growth, physiology, and yield. In lab and hydroponic experiments, osmotic stress levels (control, -2, -4, -6 and -8 Bars) created by PEG-6000, caused a significant decline in germination, mean germination time, root, shoot, and coleoptile length in both wheat genotypes examined. Germination was inhibited more in Wafaq-2001 than in Chakwal-50. Wafaq-2001 showed a higher susceptibility index based on root and shoot dry weight than did Chakwal-50. Wheat plants exhibited osmotic adjustment through the accumulation of proline, soluble sugars, soluble proteins, and free amino acids, and increased antioxidation activities of superoxide dismutase, peroxidase, catalase, and malondialdehyde. Increasing water deficit stress caused a linear decline in chlorophyll contents, leaf membrane stability, and relative water content in all wheat plants, with Wafaq-2001 showing a more severe negative impact on these parameters with increasing stress levels. The results suggest the possibility of utilizing some of these parameters as quantitative indicators of water stress tolerance in plants. Gas exchange measurements (photosynthesis, transpiration, stomatal conductance), leaf osmotic potential, water potential, and yield attributes decreased more abruptly with increasing water deficit, whereas leaf cuticular wax content increased in both genotypes, with more severe impacts on Wagaq-2001. More reduction in biochemical, physiological, and yield attributes was observed in Wafaq-2001 than was observed in Chakwal-50. Based on these results, we can conclude that Chakwal-50 is a more drought-tolerant genotype, and has excellent potential for future use in breeding programs to improve wheat drought tolerance.

11.
Cardiovasc Res ; 105(3): 260-70, 2015 Mar 01.
Article En | MEDLINE | ID: mdl-25560320

AIMS: Crosstalk between cardiomyocytes and fibroblasts in physiological conditions and during disease remains poorly defined. Previous studies have shown that fibroblasts and myocytes interact via paracrine communication, but several experimental confounding factors, including the use of immature myocytes and the induction of alpha-smooth muscle actin (α-SMA) expression in fibroblasts by prolonged culture, have hindered our understanding of this phenomenon. We hypothesize that fibroblasts and myofibroblasts differentially affect cardiomyocytes viability, volume, and Ca(2+) handling via soluble mediators. More specifically here: (i) we compare the effects of freshly isolated fibroblasts and cultured fibroblasts from normal rat hearts on adult cardiomyocytes; (ii) we compare the effects of (freshly isolated) normal fibroblasts and myofibroblasts from pressure-overloaded hearts; and (iii) we study the contribution of TGF-ß and the importance of the crosstalk between the two cell types. METHODS AND RESULTS: We used co-culture methods and conditioned medium to investigate paracrine interaction between fibroblasts and cardiomyocytes. All fibroblast types reduce cardiomyocyte viability and increase cardiomyocyte volume but α-SMA-negative fibroblasts increase cardiomyocyte Ca(2+) transient amplitude, whereas cultured fibroblasts and myofibroblasts from pressure-overloaded hearts decrease Ca(2+) transient amplitude. In turn, cardiomyocytes release soluble mediators that affect fibroblast proliferation. Using SB431542 to block TGF-ß type 1 receptors, we determined that TGF-ß directly causes cardiomyocyte hypertrophy and participates in bi-directional regulatory signalling between fibroblasts and cardiomyocytes. CONCLUSIONS: Fibroblasts have different roles during physiology and disease in regulating myocardial function via soluble mediators. A crosstalk between fibroblasts and cardiomyocytes, controlled by TGF-ß, is crucial in this interaction.


Cardiomegaly/metabolism , Fibroblasts/metabolism , Myocytes, Cardiac/metabolism , Paracrine Communication , Transforming Growth Factor beta/metabolism , Animals , Calcium Signaling , Cardiomegaly/pathology , Cell Proliferation , Cell Size , Cell Survival , Cells, Cultured , Coculture Techniques , Culture Media, Conditioned/metabolism , Disease Models, Animal , Fibroblasts/pathology , Membrane Potentials , Myocytes, Cardiac/pathology , Myofibroblasts/metabolism , Myofibroblasts/pathology , Protein Serine-Threonine Kinases/metabolism , Rats, Inbred Lew , Receptor, Transforming Growth Factor-beta Type I , Receptors, Transforming Growth Factor beta/metabolism , Time Factors
12.
J Mol Cell Cardiol ; 51(3): 390-8, 2011 Sep.
Article En | MEDLINE | ID: mdl-21740909

Electrophysiological and pharmacological data from the human heart are limited due to the absence of simple but representative experimental model systems of human myocardium. The aim of this study was to establish and characterise adult human myocardial slices from small patients' heart biopsies as a simple, reproducible and relevant preparation suitable for the study of human cardiac tissue at the multicellular level. Vibratome-cut myocardial slices were prepared from left ventricular biopsies obtained from end-stage heart failure patients undergoing heart transplant or ventricular assist device implantation, and from hearts of normal dogs. Multiple slices were prepared from each biopsy. Regular contractility was observed at a range of stimulation frequencies (0.1-2 Hz), and stable electrical activity, monitored using multi-electrode arrays (MEA), was maintained for at least 8 h from slice preparation. ATP/ADP and phosphocreatine/creatine ratios were comparable to intact organ values, and morphology and gap junction distribution were representative of native myocardium. MEA recordings showed that field potential duration (FPD) and conduction velocity (CV) in human and dog slices were similar to the values previously reported for papillary muscles, ventricular wedges and whole hearts. Longitudinal CV was significantly faster than transversal CV, with an anisotropic ratio of 3:1 for human and 2.3:1 for dog slices. Importantly, slices responded to the application of E-4031, chromanol and 4-aminopyridine, three potassium channel blockers known to affect action potential duration, with an increase in FPD. We conclude that viable myocardial slices with preserved structural, biochemical and electrophysiological properties can be prepared from adult human and canine heart biopsies and offer a novel preparation suitable for the study of heart failure and drug screening.


Heart/drug effects , Heart/physiology , Adult , Animals , Dogs , Electrophysiological Phenomena/drug effects , Electrophysiological Phenomena/physiology , Heart Conduction System/drug effects , Heart Conduction System/physiology , Humans , In Vitro Techniques , Middle Aged , Myocardium/metabolism , Myocardium/pathology , Potassium Channel Blockers/pharmacology , Tissue Survival/physiology
...