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

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

Received 15th October 2015 Accepted 29th October 2015 Published 10th November 2015Aims: 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

Enhancement of PLA-PVA surface adhesion in bilayer assemblies by PLA aminolisation

Data Availability: The raw/processed data required to reproduce these findings cannot be shared at this time due to legal or ethical reasons.Poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) present complementary barrier properties, and their combination in multilayer assemblies (laminates) could provide materials with more effective barrier capacity for food packaging purposes. However, their low chemical affinity compromises adequate polymer adhesion. Surface free energy modification of thermo-processed PLA films through treatment with 1,6-hexanediamine was used to enhance adhesion with polar PVA aqueous solutions. Treatments of 1 and 3 min increased the polar component of the solid surface tension, while treatments above 10 min provoked a corrosive effect in the films structure. Extensibility analyses of PVA solutions loaded with carvacrol (15 wt.%) and different Tween 85 ratios on PLA-activated surfaces allowed the selection of the 1-min aminolysed surface for obtaining PLA-PVA bilayers, by casting PVA solutions on the PLA films. This study revealed that despite aminolisation enhancing the PLA surface affinity for aqueous PVA solutions, casting-obtained bilayers presented limited oxygen barrier effectiveness due to heterogeneous thickness of PVA layer in the laminates.The authors acknowledge the financial support provided by the Ministerio de Economia y Competitividad (MINECO) of Spain (project AGL2016-76699-R). The author A. Tampau thanks MINECO for the pre-doctoral research grant #BES-2014-068100.info:eu-repo/semantics/publishedVersio

Modulation of the gelation efficiency of fibrillar and spherical aggregates by means of thiolation

Fibrillar and spherical aggregates were prepared from whey protein isolate (WPI). These aggregates were thiolated to a substantial degree to observe any impact on functionality. Sulfur-containing groups were introduced on these aggregates which could be converted to thiol groups by deblocking. Changes on a molecular and microstructural level were studied using tryptophan fluorescence, transmission electron microscopy, and particle size analysis. The average size (nm) of spherical aggregates increased from 38 to 68 nm (blocked variant) and 106 nm (deblocked variant) after thiolation, whereas the structure of fibrillar aggregates was not affected. Subsequently, gels containing these different aggregates were prepared. Rheological measurements showed that thiolation decreased the gelation concentration and increased gel strength for both WPI fibrillar and spherical aggregates. This effect was more pronounced upon thiolation of preformed fibrillar aggregates. The findings suggest that thiolation at a protein aggregate level is a promising strategy to increase gelation efficiency