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To develop a green nanomaterial for specialty applications, spherical nanocellulose (SNC) was functionalized to a semicarbazone-Schiff base via a polymer analogous reaction. Firstly, SNC was synthesized from cellulose extracted from huge forest biomass, pine needles (PNs). The glucopyranose ring of SNC was oxidatively cleaved at C2-C3 to form SNC-dialdehyde (SNC-DA) by periodate oxidation. Both the aldehydic groups generated were reacted with semicarbazide to form a semicarbazone-Schiff base, referred to as functional spherical nanocellulose (FSNC). All the materials synthesized were characterized by FTIR, FESEM, EDS, TEM, and XRD studies. The FSNC was evaluated as an adsorbent for [Hg.sup.2+] ions. The adsorption adhered to pseudo-second order kinetics and Langmuir adsorption isotherm having a maximum adsorption capacity/Lungmuir adsorption capacity of 172.412 mg/g at 60 min. The selectivity of FSNC for [Hg.sup.2+] ions was confirmed from its appreciable removal (82%) from solution in tap water and 70% with other metal ions. FSNC exhibited bifunctional nature as it possesses antimicrobial activity against bacteria, that is, Gram (+) (Bacillus aereus) and Gram (--) (Escherichia coll and Salmonella typhi), and a fungus Byssochlamys fiilva. FSNC showed good recyclability up to eight sorption-desorption cycles. Thus, we have valorized biomass into an eco-friendly and low-cost bifunctional material as an adsorbent for [Hg.sup.2+] ions cum antimicrobial agent. Highlights * Spherical nanocellulose (SNC) prepared via acidic hydrolysis from pine needles * SNC functionalized to semicarbazone-based bifunctional Schiff base * The Schiff base is a rapid and efficient [Hg.sup.2+] ions adsorbent * The Schiff base has good antimicrobial activities against Gram (-) bacteria * Biowaste-based adsorbent has the potential to sustain the bio-circular economy KEYWORDS antimicrobial, pine needles, Schiff base, semicarbazone, spherical nanocellulose, 1 | INTRODUCTION The sustainability development goals have a deep link with the failing water quality and low availability of drinkable water across the world. (1) Among different pollutants, dyes [...]

In this study, a wound-healing membrane was fabricated based on carboxymethyl cellulose (CMC) and polyethylene glycol (PEG) containing curcumin (Cur) and bromelain (Br). Citric acid (CA) was used as a cross-linking agent. This membrane showed an ideal degree of swelling, which was significantly dependent on the concentration and duration of cross-linked CA. The chemical characterization showed the CA cross-linker mechanism was more associated with chemical reactions with CMC carboxyl groups, and PEG hydroxyl groups played an important role in forming a hybrid polymer network. It greatly enhanced mechanical and adhesive properties, so the stress strength was improved from 29.4 to 38.52 Mpa. The hydrophilicity of the membrane surface according to the water contact angle assay showed the membrane surface is suitable for adhesion, growth, migration, and proliferation of skin cells. The drug delivery assay demonstrated that the Br and Cur were released during 48 h, but the Br followed the burst release in comparison with Cur. Antibacterial properties showed that CMC/PEG-Cur/Br have ideal antibacterial properties for preventing the growth of bacteria. In summary, the engineered CMC/PEG containing Cur/Br films with desired cell viability properties and antibacterial activity can potentially improve and accelerate skin regeneration for chronic wound healing. Highlights * Hydrogel film was prepared based on carboxymethyl cellulose (CMC), polyethylene glycol (PEG), and citric acid as cross-linking agent. * CMC/PEG film were induced controlling curcumin (Cur) and bromelain (Br) release for wound healing process. * CMC/PEG film revealed a wide range of physiochemical, mechanical, adhesion, and biological properties behavior. * Incorporation of Cur and Br promoted in vitro biocompatibility, L-929 cells attachments, and cell migration. KEYWORDS antibacterial properties, bromelain, carboxymethyl cellulose, curcumin, drug delivery, polyethylene glycol, wound dressing, 1 | INTRODUCTION As the largest human tissue, the skin serves a crucial role as a barrier against infection. (1) Due to an incomplete physical barrier and exposed subcutaneous tissue, [...]

A lot has been written about the possibility of humans contracting diseases from animals (https://www.anthropocenemagazine.org/2016/04/wildlife-markets-spread-disease/) as we push into wild places: Ebola and the virus behind the recent COVID-19 pandemic [...]

Background Diverse bacterial group behaviors are controlled by quorum sensing, a regulatory network of bacterial gene expression based on cell density, and involving communication through chemical signal molecules called autoinducers. Multidisciplinary research in toxigenic Vibrio cholerae the etiologic agent of cholera, appear to suggest group behavior in the ecology, epidemiology, pathogenesis and transmission of the pathogen. This review summarizes latest advances and known aspects of quorum regulated environmental survival form of V. cholerae, and their role in cholera outbreaks, as well as the significance of this knowledge in tracking the pathogen for prevention of cholera. Main body Pathogenic V. cholerae naturally exists in aquatic reservoirs, and infects humans, often leading to epidemic outbreaks of cholera. Effective detection and monitoring of the pathogen in surface waters have been a research focus in preventing cholera outbreaks. However, in the aquatic reservoirs, V. cholerae persists mostly in a quiescent state referred to as viable but non-culturable (VBNC), or conditionally viable environmental cells (CVEC), which fail to grow in routine bacteriological culture. The presence of CVEC can, however, be observed by fluorescent antibody based microscopy, and they appear as clumps of cells embedded in an exopolysaccharide matrix. Current studies suggest that CVEC found in water are derived from in-vivo formed biofilms excreted by cholera patients. The transition to CVEC occurs when dilution of autoinducers in water blocks quorum-mediated regulatory responses that would normally disperse the cellular aggregates. Consequently, CVEC are resuscitated to actively growing cells if autoinducers are replenished, either in the laboratory, or naturally by other environmental bacteria or the intestinal microbiota when CVEC are ingested by humans or aquatic animals. Conclusion Quorum sensing plays a crucial role in the environmental persistence of toxigenic V. cholerae in a latent state, and their periodic emergence to cause cholera outbreaks. Furthermore, the autoinducer driven resuscitation of these cells may be a basis for improving the detection of V. cholerae in water samples, and monitoring V. cholerae in their aquatic reservoirs in cholera endemic areas. Keywords: Cholera, Vibrio cholerae, Biofilms, Quorum sensing, Autoinducers, Conditionally viable environmental cells (CVEC), Author(s): Shah Nayeem Faruque[sup.1,2], Shinji Yamasaki[sup.3,4] and Shah M. Faruque[sup.5] Background Epidemics of cholera due to infection with toxigenic Vibrio cholerae O1 continue to be a significant public health problem [...]

Author(s): Bibin Mohan[sup.1], Padikkamannil Abishad[sup.1], Pokkittath Radhakrishnan Arya[sup.1], Marita Dias[sup.1], Valil Kunjukunju Vinod[sup.1], Asha Karthikeyan[sup.1], Sanis Juliet[sup.2], Nitin Vasantrao Kurkure[sup.3], Sukhadeo Baliram Barbuddhe[sup.4], Deepak Bhiwa Rawool[sup.4] and Jess Vergis[sup.1] Background [...], Background Bioinspired nanomaterials have widely been employed as suitable alternatives for controlling biofilm and pathogens due to their distinctive physico-chemical properties. Methodology This study explored the antibiofilm as well as photocatalytic potential of silver (Ag) nanoparticles (NPs) synthesized using the cell-free supernatant of Lactobacillus acidophilus for the disinfection of multi-drug-resistant (MDR) strains of enteroaggregative E. coli (EAEC), Salmonella Typhimurium, S. Enteritidis and methicillin-resistant Staphylococcus aureus (MRSA) on exposure to LED light. In addition, the removal of toxic cationic dyes i.e., methylene blue (MB), rhodamine B (RhB) and crystal violet (CV) was explored on exposure to sunlight, LED and UV lights. Results Initially, the synthesis of AgNPs was verified using UV- Vis spectroscopy, X-ray diffraction and transmission electron microscopy. The synthesized AgNPs exhibited MIC and MBC values of 7.80 and 15.625 [micro]g/mL, respectively. The AgNPs exhibited significant inhibition (P < 0.001) in the biofilm-forming ability of all the tested MDR isolates. On exposure to LED light, the AgNPs could effectively eliminate all the tested MDR isolates in a dose-dependent manner. While performing photocatalytic assays, the degradation of RhB was observed to be quite slower than MB and CV irrespective of the tested light sources. Moreover, the sunlight as well as UV light exhibited better photodegradation capacity than LED light. Notwithstanding the light sources, RhB followed zero-order kinetics; however, MB and CV followed primarily second-order kinetics. Conclusion The green synthesized AgNPs were found to be an effective photocatalytic as well as antifouling candidate that could be applied in therapeutics and wastewater treatment. Keywords: Antibiofilm, Disinfection, Dye removal, Nanoparticle, Photocatalysis, Probiotic, Silver