A comparative study of the adhesion of biosynthesized gold and conjugated gold/prodigiosin nanoparticles to triple negative breast cancer cells.

This paper explores the adhesion of biosynthesized gold nanoparticles (AuNPs) and gold (Au) nanoparticle/prodigiosin (PG) drug nanoparticles to breast cancer cells (MDA-MB-231 cells). The AuNPs were synthesized in a record time (less than 30 s) from Nauclea latifolia leaf extracts, while the PG was produced via bacterial synthesis with Serratia marcescens sp. The size distributions and shapes of the resulting AuNPs were characterized using transmission electron microscopy (TEM), while the resulting hydrodynamic diameters and polydispersity indices were studied using dynamic light scattering (DLS). Atomic Force Microscopy (AFM) was used to study the adhesion between the synthesized gold nanoparticles (AuNPs)/LHRH-conjugated AuNPs and triple negative breast cancer cells (MDA-MB-231 cells), as well as the adhesion between LHRH-conjugated AuNP/PG drug and MDA-MB-231 breast cancer cells. The adhesion forces between LHRH-conjugated AuNPs and breast cancer cells are shown to be five times greater than those between AuNPs and normal breast cells. The increase in adhesion is shown to be due to the over-expression of LHRH receptors on the surfaces of MDA-MB-231 breast cancer cells, which was revealed by confocal immuno-fluorescence microscopy. The implications of the results are then discussed for the selective and specific targeting and treatment of triple negative breast cancer.

Towards an understanding of bacterial metabolites prodigiosin and violacein and their potential for use in commercial sunscreens.

OBJECTIVES: To exploit the microbial ecology of bacterial metabolite production and, specifically, to: (i) evaluate the potential use of the pigments prodigiosin and violacein as additives to commercial sunscreens for protection of human skin, and (ii) determine antioxidant and antimicrobial activities (against pathogenic bacteria) for these two pigments. METHODS: Prodigiosin and violacein were used to supplement extracts of Aloe vera leaf and Cucumis sativus (cucumber) fruit which are known to have photoprotective activity, as well as some commercial sunscreen preparations. For each, sunscreen protection factors (SPFs) were determined spectrophotometrically. Assays for antimicrobial activity were carried out using 96-well plates to quantify growth inhibition of Staphylococcus aureus and Escherichia coli. RESULTS: For the plant extracts, SPFs were increased by an order of magnitude (i.e. up to ~3.5) and those for the commercial sunscreens increased by 10-22% (for 4% w/w violacein) and 20-65% (for 4% w/w prodigiosin). The antioxidant activities of prodigiosin and violacein were approximately 30% and 20% those of ascorbic acid (a well-characterized, potent antioxidant). Violacein inhibited S. aureus (IC50 6.99 ± 0.146 µM) but not E. coli, whereas prodigiosin was effective against both of these bacteria (IC50 values were 0.68 ± 0.06 µM and 0.53 ± 0.03 µM, respectively). CONCLUSION: The bacterial pigments prodigiosin and violacein exhibited antioxidant and antimicrobial activities and were able to increase the SPF of commercial sunscreens as well as the extracts of the two plant species tested. These pigments have potential as ingredients for a new product range of and, indeed, represent a new paradigm for sunscreens that utilize substances of biological origin. We discussed the biotechnological potential of these bacterial metabolites for use in commercial sunscreens, and the need for studies of mammalian cells to determine safety.

[Effect of prodigiozan on the course of candidiasis of the oral mucosa clinically and in an experiment]. / Vliianie prodigiozana na techenie kandidoza slizistoi obolochki polosti rta v klinike i éksperimente

The effect of various doses of prodigiozan on Candida infection was studied under experimental and clinical conditions. Hamsters and guinea pigs were used in the experiments. Prodigiozan was administered intramuscularly to the hamsters in doses of 100 gamma/kg of the body weight 1 hour before the infection and intracutaneously to the guinea pigs in doses of 50 gamma/kg 2 days before the infection. The results showed that the drug accelerated the recovery of the animals. In complex therapy of a group of 22 patients with candidosis of the mouth mucosa of various localization prodigiozan was administered thrice in doses of 50 gamma/kg. This provided faster elimination of the pathological process.