Bostrycin, a novel coupling agent for protein immobilization and prevention of biomaterial-centered infection produced by Nigrospora sp. No. 407

Enhancing the Performance of Reversible Zn Deposition by Ultrathin Polyelectrolyte Coatings

Modifying the surfaces of zinc and other metallic substrates is considered an effective strategy to enhance the reversibility of the zinc deposition and stripping processes. While a variety of surface modification strategies have been explored, their ability to be practically implemented is not always trivial due to the associated high costs and complexity of the proposed techniques. In this study, we showcase a straightforward method for preparing ultrathin polyelectrolyte coatings using polydiallyldimethylammonium chloride (PDDA) and polyethylenimine (PEI). The coatings, characterized by their electrostatic charge and hydrophobicity, suppress side reactions and even out the electrodeposition process across the substrate surface. The PDDA-coated anodes demonstrate significantly reduced voltage hysteresis, uniform zinc morphology, improved self-discharge rates, and an impressive Coulombic efficiency exceeding 99% over prolonged cycling. Our findings highlight the potential that such cost-effective and straightforward surface treatments could be widely applied in Zn metal-based batteries.

Protein kinases as targets for developing anticancer agents from marine organisms

Protein kinases play a fundamental role in the intracellular transduction because of their ability to phosphorylate plethora of proteins. Over the past three decades, numerous protein kinase inhibitors have been identified and are being used clinically successfully. The biodiversity of marine organisms provides a rich source for the discovery and development of novel anticancer agents in the treatment of human malignancies and a lot of bioactive ingredients from marine organisms display anticancer effects by affecting the protein kinases-mediated pathways. In the present mini-review, anticancer compounds from marine source were reviewed and discussed in context of their targeted pathways associated with protein kinases and the progress of these compounds as anticancer agents in recent five years were emphasized. The molecular entities and their modes of actions were presented. We focused on protein kinases-mediated signaling pathways including PI3K/Akt/mTOR, p38 MAPK, and EGFR. The marine compounds targeting special pathways of protein kinases were highlighted. We have also discussed the existing challenges and prospects related to design and development of novel protein kinase inhibitors from marine sources.

Electrospun silver ion-loaded calcium phosphate/chitosan antibacterial composite fibrous membranes for guided bone regeneration

PURPOSE

The purpose of this study is to construct a guided bone regeneration membrane that is similar to bone components and structurally resembles the native extracellular matrix with sufficient antibacterial properties.

MATERIALS AND METHODS

A novel type of biomimetic and bioactive silver ion-loaded calcium phosphate/chitosan (Ag-CaP/CS) membrane with antibacterial ability was successfully developed by incorporation of silver ion-loaded CaP via a one-step electrospinning method and subsequently crosslinked with vanillin.

RESULTS

Evaluation of the physicochemical properties revealed that the fabricated fibrous membranes mimicked the extracellular matrix structure and the addition of CaP significantly increased the mineralization ability of the membranes. Importantly, the Ag-CaP/CS membranes exhibited a sustainable release of Ag+, which in turn inhibited the adhesion and growth of Staphylococcus mutans. The results of cell adhesion and MTT assay revealed that the Ag-CaP/CS membranes were cytocompatible with bone marrow stromal cells.

CONCLUSION

The fabricated electrospinning Ag-CaP/CS nanofiber membranes with excellent biocompatibility and strong antimicrobial properties have great potential to be used for guided bone regeneration.

Bostrycin production by agro-industrial residues and its potential for food processing

Bostrycin, a red antibacterial agent produced by Nigrospora sp. no. 407, is considered for meat processing. To optimize production, the culture conditions of submerged fermentation (SmF) and solid-state fermentation (SSF) were investigated. The optimal SmF conditions were a medium containing 1.0% cane molasses and incubation at 30 °C and 150 rpm for 6 days. In SSF, other than bostrycin, less pigment was produced and the optimal ratio of bagasse to water was 1:2 for 10 days. The production and recovery rate of bostrycin by SmF were 120 mg/L and 40%, respectively. Bostrycin exhibited thermostable, pH-dependent color change and dose-dependent antibacterial activity against Clostridium botulinum. Bostrycin-modified meat turned strong red for at least 24 h and could not be removed by washing; bostrycin maintained its antibacterial activity with a bacteriostasis rate of 91% on Staphylcoccus aureus. This is an easy and inexpensive means of acquiring bostrycin from molasses and sugarcane.

Anthraquinones and Derivatives from Marine-Derived Fungi: Structural Diversity and Selected Biological Activities

Anthraquinones and their derivatives constitute a large group of quinoid compounds with about 700 molecules described. They are widespread in fungi and their chemical diversity and biological activities recently attracted attention of industries in such fields as pharmaceuticals, clothes dyeing, and food colorants. Their positive and/or negative effect(s) due to the 9,10-anthracenedione structure and its substituents are still not clearly understood and their potential roles or effects on human health are today strongly discussed among scientists. As marine microorganisms recently appeared as producers of an astonishing variety of structurally unique secondary metabolites, they may represent a promising resource for identifying new candidates for therapeutic drugs or daily additives. Within this review, we investigate the present knowledge about the anthraquinones and derivatives listed to date from marine-derived filamentous fungi's productions. This overview highlights the molecules which have been identified in microorganisms for the first time. The structures and colors of the anthraquinoid compounds come along with the known roles of some molecules in the life of the organisms. Some specific biological activities are also described. This may help to open doors towards innovative natural substances.

Polyethyleneimine for copper absorption II: kinetics, selectivity and efficiency from seawater

Nano-thin coatings of glutaraldehyde cross-linked polyethyleneimine effectively and selectively accumulated copper from natural seawater.