• Antioxidant, Anticancer and Antibacterial Activity of Withania somnifera Aqueous Root Extract

      Barnes, D. A.; Barlow, R.; Nigam, Poonam S.; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain international, 2015-11-10)
      Aims: To evaluate total antioxidant capacity, anticancer activity and antibacterial effects Withania somnifera aqueous-root extracts. Study Design: In vitro study. Place of Study: School of Biomedical Sciences, Ulster University, UK. Methodology: Total antioxidant capacity (TAC) of whole powder and freeze dried W. somnifera aqueous-root extracts was determined using FRAP, DPPH, Folin and ABTS assays. Anticancer activity was accessed using MDA-MB-231 breast cells and Sulforhodamine B staining for cell viability. Antibacterial activity was by disk diffusion assay with penicillin, amoxicillin and streptomycin as positive controls. Results: The TAC for W. somnifera extract was 86, 47, 195,or 443 gallic acid equivalents per 100g dry basis (mgGAE/ 100 g) using FRAP, DPPH, Folin or ABTS assays, respectively. Corresponding TAC values for freeze dried W. somnifera aqueous-root extract were, 418, 553, 1898 or, 1770 (mgGAE/100 g). W. somnifera aqueous-root extract inhibited MDA-MB-231 cell proliferation in a dose-dependent manner with IC50 = 0.19 mg/ml (21 µM GAE). Nil antibacterial effects were detected for freeze dried W. somnifera extract (0-1 mg/ml) across six species of bacteria tested. Conclusion: Withania somnifera root water extract showed significant antioxidant and anticancer activity for MDA-MB-231 breast cancer cells but no antibacterial activity under the conditions of this study.
    • Antioxidant, Anticancer and Antimicrobial, Effects of Rubia cordifolia Aqueous Root Extract

      Barlow, R.; Barnes, D. A.; Campbell, Anna M.; Nigam, Poonam S.; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain international, 2015-11-10)
      Aims: To evaluate the total antioxidant capacity (TAC) of Rubia cordifolia root extracts, to test anticancer activity against MDA-MB-231 breast cancer cell lines, and to evaluate antimicrobial activity of the same extract versus six Gram-positive and negative bacteria. Study Design: In vitro. Place of Study and Duration: School of Biomedical Sciences, Ulster University, July 2014-Sept 2015. Methodology: TAC was tested using ABTS, DPPH, FRAP and Folin assays and values were expressed as mg-gallic acid equivalents per 100 g (GAE/100 g) of sample. Anticancer properties were examined against MDA-MB-231 breast cancer cell lines using Sulforhodamine B assay. Antimicrobial activity was examined using a disk diffusion assay with three Gram-positive (Staphylococcus epidermidis, Staphylococcus aureus and Bacillus cereus) and three Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi) bacteria. Results: TAC of dry extracts of Rubia cordifolia ranged from 523±43 to 4513±208 (mg GAE mg/100 g) depending on the method of analysis, ABTS> FRAP> Folin > DPPH methods. R. cordifolia dry extract showed cytotoxicity against MDA-MB-231 with IC50 = 44 µg/ml or 5.1µM GAE. No antimicrobial activity was observed against the three Gram-positive, or three Gram-negative bacterial species using the water extract or R. cordifolia. Conclusion: R. cordifolia aqueous extract possess high total antioxidant capacity but values depend on the method of analysis. R. cordifolia extract inhibits MDA-MB-231 breast cancer cells proliferation but nil anti-bacterial activity was observed for three Gram-positive and three Gram-negative bacterial strains tested.
    • Effects of ascorbic acid, dehydroascorbic acid and methotrexate on breast cancer cell viability.

      Dosunmu, Yewande; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain international, 2017-10-28)
      Aims: To examine the effects of ascorbic acid (AA), dehydroascorbic acid (DHA) and methotrexate (MTX) combined treatments on (MDA-MB-231) breast cancer cell viability and intracellular reactive oxygen species (ROS). Study Design: In-vitro method. Place and Duration of Study: Biomedical Sciences Research Institute, University of Ulster, Coleraine, BT52 1SA, United Kingdom. September 2016-2017 Methodology: Cytotoxicity tests were performed with MTX (0.01- 1000 µmol/l) alone or in combination with AA or DHA, for 72 h. Cell viability was measured by 3-4,5 dimethylthiazol-2,5 diphenyl tetrazolium bromide (MTT) or Sulforhodamine B (SRB) assays. Intracellular ROS was measured by 2’,7’-dichlorofluroscein diacetate assay. Results: Treatments of MDA-MB231 cells with single agents, showed dose dependent response with 50% inhibition of cell viability (IC50) of 110.5-201.4 µmol/l (MTX), 2237-5703 µmol/l (AA) or 2474 µmol/l (DHA). Combination studies showed clear synergisms for MTX (~10 µmol/l) and DHA or AA (1100 µmol/l) but weak or no interactions at other concentrations. Three days combination treatment of DHA showed decrease of ROS, which was reversed by MTX (>10 µmol/l). Conclusions: Co-treatment of methotrexate with AA or DHA showed synergism (C1<1.0) and enhanced cytotoxicity of the anti-folate towards MDA-MB-231 breast cancer cells. Intracellular ROS decreased with AA and DHA treatment, which might be useful for reducing MTX-related oxidative stress.
    • Enhanced growth-inhibitory effect of microemulsified curcumin formulation in human prostate cancer LNCaP Cells

      Dubey, Vaibhav; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain international, 2015-01-01)
      Aim: To assess the effect of curcumin microemulsified with non-ionic surfactant surfynol 465 W or dispersed using edible oils on prostate LNCaP cancer cell viability and glutathione status. Methodology: LNCaP cells were treated for 72-144 hr with curcumin dissolved with fish or corn oil and microemulsified using non-ionic surfactant surfynol 465 W; alternatively LNCaP cells were treated with curcumin directly dispersed in fish or corn oil (0-50 μM) for 24 -72-144 hr. Cell viability was determined using resazurin (Vision blueTM) fluorescence assay. Glutathione status was determined by monochlorobimane (MCB) assay. Results: Treatment with 0-34 μM of microemulsified curcumin produced moderate cytotoxic effect on LNCaP cells, no 50% reduction of cell viability was observed graphically. However, when LNCaP cells were treated with curcumin dispersed with corn oil the concentration or 50% reduction of cell viability (IC50) was 12-45 μM. Similarly for cells treated with curcumin dispersed with fish oil, the IC50 was between 20-40 μM. Cytotoxic doses of curcumin dispersed with corn or fish oil increased GST status in cells by 272-656% (p =<0.01). Conclusion: Microemulsified curcumin formulation prepared using fish or corn oil and surfynol 465 W surfactant had an inhibitory effect on viability of LNCaP cells as did direct dispersion of curcumin in fish or corn oil coupled with the ability for inducing intracellular GST status in LNCaP cells.
    • Rapid Colorimetric Determination of Methylglyoxal Equivalents for Manuka Honey

      Kwok, T. H.; Kirkpatrick, G.; Yusof, H. I. Mohd; Portokalakis, I; Nigam, Poonam S.; Owusu-Apenten, Richard K.; University of Chester, University of Ulster (Sciencedomain international, 2016-06-14)
      Aims: Realization of a rapid colorimetric assay for monitoring levels of methylglyoxal and other dicarbonyl compounds from Manuka honey. Methods: N-acetyl cysteine (NAC) and 2, 4-dinitrophenylhydrazine (DNPH) were adopted as reagents for methylglyoxal colorimetric analysis of honey at 288 or 525 nm, respectively. Results and Discussion: NAC and DNPH produced linear responses for methylglyoxal with:(i) regression coefficient (R2) equal to 0.99 or 0.97, (ii) molar absorptivity (measure of sensitivity) equal to 287±11 or 14189±498 M-1 cm-1, (iii) a minimum detectable concentration (MDC) of 0.18 mM vs 7.3 µM, (iv) upper linearity limit of linearity (ULL) equal to 4mM or 83 µM, and (v) a day-to-day precision of 16.0 and 18.3%, respectively. Low interferences occurred with reducing sugars, glyoxal or 3-deoxy-D-glucosone. For honey with a unique manuka factor (UMF) rating 5+ to UMF18+, the net concentration of dicarbonyl compounds ranged from 1069 mg-methylglyoxal equivalence per kg (mg MeGEq /kg) to 2208 (mg MeGEq /kg) using the NAC assay. For the DNPH assay, the apparent dicarbonyl concentration was 350 to 1009-mg MeGEq /kg honey. Measures of methylglyoxal equivalences were strongly correlated with the UMF rating for honeys (R2=0.98-0.99). Conclusion: The proposed colorimetric analysis of methylglyoxal equivalence in Manuka honey is feasible proposition. Further work is needed for method validation.