Faculty of Applied Sciences
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Item Sulfonic acid functionalized boron nitride nano materials as a microwave-assisted efficient and highly biologically active one-pot synthesis of piperazinyl-quinolinyl fused Benzo[c]acridine derivatives(Elsevier, 2017) Murugesan, Arul; Gengan, Robert Moonsamy; Anand, KrishnanBoron nitride nano material based solid acid catalyst was found to be an efficient and reusable sulfonic acid catalyst for the synthesis of one-pot Knoevenagel and Michael type reactions in 3, 3-dimethyl-9-(2-(4-methylpiperazin-1-yl) quinolin-3-yl)-3, 4, 9, 10-tetrahydroacridin-1(2H)-one derivatives under mi-crowave irradiation conditions. The catalyst was prepared by mixing boron nitrile and (3-mercaptopropyl) trimethoxysilane. This is simple and safe method for the preparation of solid acid catalysts. The morphological properties of catalyst determined by using FT-IR, XRD, TEM, SEM and Raman spectroscopy. The synthesised catalyst was employed in Knoevenagel and Michael type reactions to synthesise novel piperazinyl-quinolinyl based acridine derivatives. Furthermore the newly-synthesised compounds have been used for molecular docking in DNA binding studies. The method developed in this study has the advantages of good yield, simplicity coupled with safety and short reaction time. Most importantly it was found that the solid acid catalyst can be recycled with only 5% loss of activity.Item Design, synthesis, anticancer, antimicrobial activities and molecular docking studies of novel quinoline bearing dihydropyridines(Elsevier, 2016) Nkosi, S'busiso Mfan'vele; Anand, Krishnan; Anandakumar, S.; Singh, Sanil; Chuturgoon, Anil A.; Gengan, Robert MoonsamyA new series of eight quinoline bearing dihydropyridine derivatives (A1–A8) were synthesized in high yield and in short reaction time by a four component reaction of 2-chloro-3-fomyl quinoline, malononitrile, arylamines and dimethyl acetylenedicarboxylate in the presence of a catalytic amount of triethylamine. The compounds were fully characterized by IR, NMR and GC–MS. These compounds were screened for potential biological activity in an A549 lung cancer cell line and were also evaluated for their antibacterial activities against Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213 whilst their molecular docking properties in an enzymatic system were also determined. Compounds A2, A3, A4 and A8 showed anti-proliferative activity; with A4 having the highest toxicity at 250 μg/mL and A8 has high toxicity at 125, 250 and 500 μg/mL, respectively. Antibacterial results indicated that A4 have significant activity against tested microorganisms at the minimum inhibitory concentration (MIC) values of 32 μg/mL against Pseudomonas aeruginosa and Escherichia coli,and 16μg/mL against Staphylococcus aureus. Docking of A1 with human mdm2 indicated the lowest binding energy (−6.111 Kcal/mol) thereby showing strong affinity of the ligand molecule with the receptor which has been stabilized by strong hydrogen bond interactions in the binding pocket. This confirms that A1 is a better inhibitor for E3 ubiquitin-protein ligase mdm2.Item Cobalt boron nitride : a novel heterogeneous catalyst for the synthesis of medicinally important α-amino quinoline phosphonates(Taylor and Fancis, 2016) Sureshkumar, M; Anand, Krishnan; Muthu, T.; Gengan, Robert MoonsamyA novel cobalt supported on boron nitride (CoBNT) heterogeneous catalyst for the synthesis of α-amino quinoline phosphonates (AQPs) is reported in the present work. The CoBNT was synthesised by simply mix-ing boron nitride in a solution of cobalt acetate, under an inert atmosphere for 7 d followed by filtration; the yield was 94%. It exhibited excellent catalytic properties for the synthesis of 16 novel AQPs in a one pot mixture containing 2-methoxy 3-formyl quinoline, aniline derivatives and diethyl phosphite. Reactions were rapid, products were easily worked-up and were obtained in more than 90% yield. The CoBNT also exhibited higher catalytic activity than conventional catalysts and was re-used five times without significant decrease in catalytic activity.Item Biosynthesis of palladium nanoparticles by using Moringa oleifera flower extract and their catalytic and biological properties(Elsevier, 2016) Anand, Krishnan; Tiloke, Charlette; Phulukdaree, Alisa; Ranjan, B.; Chuturgoon, Anil A.; Singh, S.; Gengan, Robert MoonsamyThe biosynthesis of nanostructured biopalladium nanoparticles (PdNPs) from an aqueous solution of crystalline palladium acetate is reported. For the synthesised PdNPs in solution, an agroforest biomass waste petal of Moringa oleifera derived bis-phthalate was used as natural reducing and biocapping agents. Continuous absorp-tion in the UV region and subsequent brown colour change confirmed the formation of PdNPs. A strong surface plasmon peak for PdNPs occurred at 460 nm. PdNPs were characterized by SEM with EDX, FTIR, TEM and DLS. The chemical composition of the aqueous extract was determined by GC–MS coupled with FTIR and 1NMR. The cat-alytic degradation effect by PdNPs on industrial organic toxic effluents p-nitrophenol (PNP) and methylene blue dye was monitored by UV Spectroscopy. On the other hand PdNPs catalysed the base mediated suzuki coupling reaction for biphenyl synthesis, in water. Moreover, PdNPs were found to be reusable catalysts. Toxicity studies of PdNPs showed that the death of brine shrimp to be b50%. Therefore, PdNPs displayed potential for further anti-cancer studies via tumour cell lines. The in vitro cytotoxicity evaluation of the extract capped nanoparticles was carried out using human lung carcinoma cells (A549) and peripheral lymphocytes normal cells by MTT cell via-bility assay. Also, PdNPs showed antibacterial activity against Enterococcus faecalis among the different tested strains, including Bacillus cereus, Staphylococcus aureus, Esherichia coli and Candida albicans, Candida utilis.Item Moringa oleifera gold nanoparticles modulate oncogenes, tumor suppressor genes, and Caspase-9 splice variants in A549 cells(Wiley Online Library, 2016) Tiloke, Charlette; Phulukdaree, Alisa; Anand, Krishnan; Gengan, Robert MoonsamyGold nanoparticles (AuNP's) facilitate cancer cell recognition and can be manufactured by green synthesis using nutrient rich medicinal plants such as Moringa oleifera (MO). Targeting dysregulated oncogenes and tumor suppressor genes is crucial for cancer therapeutics. We investigated the antiproliferative effects of AuNP synthesized from MO aqueous leaf extracts (MLAuNP) in A549 lung and SNO oesophageal cancer cells. A one‐pot green synthesis technique was used to synthesise MLAuNP. A549, SNO cancer cells and normal peripheral blood mononuclear cells (PBMCs) were exposed to MLAuNP and CAuNP to evaluate cytotoxicity (MTT assay); apoptosis was measured by phosphatidylserine (PS) externalization, mitochondrial depolarization (ΔΨm) (flow cytometry), caspase‐3/7, −9 activity, and ATP levels (luminometry). The mRNA expression of c‐myc, p53, Skp2, Fbw7α, and caspase‐9 splice variants was determined using qPCR, while relative protein expression of c‐myc, p53, SRp30a, Bax, Bcl‐2, Smac/DIABLO, Hsp70, and PARP‐1 were determined by Western blotting. MLAuNP and CAuNP were not cytotoxic to PBMCs, whilst its pro‐apoptotic properties were confirmed in A549 and SNO cells. MLAuNP significantly increased caspase activity in SNO cells while MLAuNP significantly increased PS externalization, ΔΨm, caspase‐9, caspase‐3/7 activities, and decreased ATP levels in A549 cells. Also, p53 mRNA and protein levels, SRp30a (P = 0.428), Bax, Smac/DIABLO and PARP‐1 24 kDa fragment levels were significantly increased. Conversely, MLAuNP significantly decreased Bcl‐2, Hsp70, Skp2, Fbw7α, c‐myc mRNA, and protein levels and activated alternate splicing with caspase‐9a splice variant being significantly increased. MLAuNP possesses antiproliferative properties and induced apoptosis in A549 cells by activating alternate splicing of caspase‐9. J. Cell. Biochem. 117: 2302–2314, 2016.Item Synthesis, characterization and thermophysical properties of ionic liquid N-methyl-N-(2′,3′-epoxypropyl)-2-oxopyrrolidinium chloride and its binary mixtures with water or ethanol at different temperatures(Elsevier, 2016) Vasanthakumar, Arumugam; Bahadur, Indra; Redhi, Gan G.; Gengan, Robert Moonsamy; Anand, KrishnanA novel ionic liquid, namely, N-methyl-N-(2′,3′-epoxypropyl)-2-oxopyrrolidiniumchloride [Epmpyr]+[Cl]− was synthesized and characterized by different techniques such as NMR (1H and 13C), FTIR, and elemental analysis. The water content of the ionic liquid was checked by Karl Fisher titration. Further, the density, ρ, and speed of sound, u, were measured for the above ionic liquid and the corresponding binary systems with water or ethanol at different temperatures ranging from (293.15 to 313.15) K. The derived thermodynamic properties for instance excess molar volumes, VE m isentropic compressibility, κs, and deviation in isentropic compressibility, Δκs, were investigated from the density and speed of sound data, respectively. It is noted that density and speed of sound of the ionic liquid and its binary mixtures were decreased with increase in temperature, whereas excess molar volume, isentropic compressibility, and deviation in isentropic compressibility values increased. Derived properties such as excess molar volumes, and deviation in isentropic compressibility data were fitted to the Redlich-Kister polynomial equation. The measured and calculated data were interpreted in terms of intermolecular interfaces and structural effects between similar and dissimilar molecules upon mixing.Item Silver nanoparticles of Albizia adianthifolia : the induction of apoptosis in human lung carcinoma cell line(BioMed Central, 2013) Govender, Rishalan; Phulukdaree, Alisa; Gengan, Robert Moonsamy; Anand, Krishnan; Chuturgoon, Anil A.Background Silver nanoparticles (AgNP), the most popular nano-compounds, possess unique properties. Albizia adianthifolia (AA) is a plant of the Fabaceae family that is rich in saponins. The biological properties of a novel AgNP, synthesized from an aqueous leaf extract of AA (AAAgNP), were investigated on A549 lung cells. Cell viability was determined by the MTT assay. Cellular oxidative status (lipid peroxidation and glutathione (GSH) levels), ATP concentration, caspase-3/-7, -8 and −9 activities were determined. Apoptosis, mitochondrial (mt) membrane depolarization (flow cytometry) and DNA fragmentation (comet assay) were assessed. The expression of CD95 receptors, p53, bax, PARP-1 and smac/DIABLO was evaluated by flow cytometry and/or western blotting. Results Silver nanoparticles of AA caused a dose-dependent decrease in cell viability with a significant increase in lipid peroxidation (5-fold vs. control; p = 0.0098) and decreased intracellular GSH (p = 0.1184). A significant 2.5-fold decrease in cellular ATP was observed upon AAAgNP exposure (p = 0.0040) with a highly significant elevation in mt depolarization (3.3-fold vs. control; p < 0.0001). Apoptosis was also significantly higher (1.5-fold) in AAAgNP treated cells (p < 0.0001) with a significant decline in expression of CD95 receptors (p = 0.0416). Silver nanoparticles of AA caused a significant 2.5-fold reduction in caspase-8 activity (p = 0.0024) with contrasting increases in caspase-3/-7 (1.7-fold vs. control; p = 0.0180) and −9 activity (1.4-fold vs. control; p = 0.0117). Western blots showed increased expression of smac/DIABLO (4.1-fold) in treated cells (p = 0.0033). Furthermore, AAAgNP significantly increased the expression of p53, bax and PARP-1 (1.2-fold; p = 0.0498, 1.6-fold; p = 0.0083 and 1.1-fold; p = 0.0359 respectively). Conclusion Data suggests that AAAgNP induces cell death in the A549 lung cells via the mt mediated intrinsic apoptotic program. Further investigation is required to potentiate the use of this novel compound in cancer therapy trials.